Article

A process for the preparation of food-grade rice bran wax and the determination of its composition

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Abstract

A two-step method was developed for the preparation of food-grade wax. The first step involved the solventdefatting of crude wax, which gave a dark brown, dry, powdered wax with a m.p. of 75–79°C. The major impurity in the defatted wax was the dark brown resinous matter. In the second step, the resinous matter was removed by bleaching with sodium borohydride in isopropanol. This step yielded a pale yellow, odorless wax with purity higher than 99% and with a m.p. of 80–83°C. The resinous matter was a mixture of aliphatic aldehydes, fatty alcohols, and FA. High-temperature GC analysis of the purified rice bran wax indicated that it contained 11 major and 9 minor types of saturated wax esters. The major and minor peaks contained C44–C64 and C45–C59 wax esters, respectively. Rice bran wax was mainly a mixture of saturated esters of C22 and C24 FA and C24 to C40 aliphatic alcohols, with C24 and C30 being the predominant FA and fatty alcohol, respectively. The alcohol portion of the wax esters also contained small amounts of branched and odd carbon number fatty alcohols.

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... Sunflower wax and rice bran wax are obtained by the winterization (gradual cooling with centrifugation or filtration) of crude sunflower oil and rice bran oil, respectively. [12,17,18] Jojoba wax (sometimes called jojoba oil because it is liquid at room temperature) is unique because it is not an epicuticular wax. Jojoba wax is a storage lipid comprised of wax esters in the seeds of jojoba seeds and it is metabolized to provide a source of energy and carbons during seed germination, similar to the way that triacylglycerols are metabolized during the germination of oilseeds. ...
... The AOCS (2009) Official Method Ch 8-02 for GC-MS of waxes (max 340 C), reports separation of wax esters up to C46. [31] The International Olive Oil Commission (IOC) developed an official GC method to analyze wax in olive oil. [32] Tada et al. reported a high temperature GC-MS method (max 390 C) that could separate up to C62. [12] Vali et al. reported a GC-MS method (max 380 C) that could separate wax esters up to C64. [18] Vichi et al. reported a direct electrospray ultrahigh resolution mass spectrometry method to analyze waxes without the need for a chromatography step. [33] Until now, high performance liquid chromatography (HPLC) methods have been of limited use for the analysis of commercial waxes and almost all of the analyses of commercial waxes have been conducted using gas chromatography (Table 1). ...
... This study is the first report of analysis of rice bran wax by HPLC-MS. Previous GC-MS studies reported esters of 44-64 carbons [18] and 46-60 carbons. [12] The ELSD and mass spectrometry chromatograms for sunflower wax also had similar major peaks ( Figure 5) as rice bran wax, which was described above (Figure 4). ...
Article
Commercial waxes are difficult to analyze due to their limited solubility in most organic solvents. Recently, our laboratory published a new reverse phase HPLC-MS method using a C30 column, a gradient of methanol and chloroform, an evaporative light-scattering detector (ELSD), and atmospheric pressure chemical ionization mass spectrometry (APCI-MS) to analyze jojoba wax (jojoba oil), carnauba wax, and sorghum wax. In the current study, the published HPLC method was modified by reducing the solvent gradient program to 60 minutes and this new method was evaluated for its usefulness for the analysis of five other commercial waxes (beeswax, rice bran, sunflower, candelilla and paraffin waxes). The ELSD appeared to detect all types of wax components, whereas the APCI-MS was most useful for the identification of wax esters and was unable to detect hydrocarbons, such as those in candelilla wax and paraffin wax. Previous HPLC methods for waxes and most GC methods for waxes only separate wax esters with size up to 54 carbons (C54) but this method was able to separate those with size up to 60 carbon wax esters. This report presents the first HPLC chromatograms for rice bran, sunflower, candelilla, and paraffin waxes. The main contribution of this work is the evidence that a C30 reverse phase HPLC system provides acceptable chromatographic separation of major components in commercial waxes.
... The content was kept for cooling and later it filtered off. This residues (50g) was again refluxed with 350ml of isopropanol for further extraction of oil at 85℃ for 45 min, Thus oil content is removed from the crude wax (Vali et al., 2005). ...
... A reddish brown color resinous material was appeared during the addition of sodium borohydride solution. Reflux action should be continued for another 70-80 minutes followed by cooling the contents to ambient temperature (Vali et al., 2005). ...
... After drying an odorless light yellow fine powder were yielded. This can be further utilized for edible coating preparation (Vali et al., 2005). ...
... Policosanols are classified as the group of high molecular weight biologically active long chains of aliphatic primary alcohols between the carbon atoms 22 to 38 (Hwang et al., 2002a(Hwang et al., , b, 2005Vali et al., 2005;Pham et al., 2018), according to their sources of occurrence such as beeswax (Irmak et al., 2005), sugarcane (Irmak et al., 2005), perilla seeds (Adhikari et al., 2006), and cereals (Hwang et al., 2005) like rice Pham et al., 2018), wheat (Irmak et al., 2005;Dunford et al., 2010;Pham et al., 2018), sorghum (Hwang et al., 2004;Leguizamón et al., 2009;Pham et al., 2018) as described in the literature. These policosanols phytochemicals are very unique in sorghum grain due to their presence in nonesterified forms (Althwab et al., 2015). ...
... Non Commercial Use (C 32 ) which are available and sold in the markets as nutritional supplements (Hwang et al., 2002b(Hwang et al., , 2005Irmak et al., 2005;Vali et al., 2005). Structure of major policosanols reported in sorghum grain is depicted in Figure 2.10. ...
... Octacosanol (C 28 ) and triacontanol (C 30 ) in sorghum grain do the representation of most predominant policosanols when compare with hexacosanol (C 26 ) and dotriacontanol (C 32 ) (Hwang et al., 2004;Leguizamón et al., 2009). These phytochemicals are gaining more popularity due to their physiological function and beneficial health effects (Figure 2.11) which have been documented in many reports worldwide (Arruzazabala et al., 1994(Arruzazabala et al., , 1996Kabir and Kimura, 1995;Kato et al., 1995;Sttisser et al., 1998;Mas et al., 1999;Castano et al., 2001;Gouni-Berthold and Berthold, 2002;Carr et al., 2005;Vali et al., 2005;Lee et al 2014). Therefore, researchers and scientists are giving more emphasis on its uses in pharmaceutical industries because of the significant presence of policosanols phytochemicals in sorghum grain (Irmak et al., 2005;Dunford et al., 2010). ...
Chapter
Sorghum, popularly known as milo, is a versatile crop which can easily grow in drought-prone areas. It has high nutritional value and is a good source of phytochemicals, that is, tannins, flavonoids, phytosterols, and policosanols. These phytochemicals have high antioxidant activity as compared with other cereals and also exhibit positive health benefits. Processing conditions result in the reduction of antioxidant properties. Consumption of sorghum in the regular diet has shown anticancerous prop- erties and prevents cardiovascular diseases, esophageal cancer, and many more. This chapter reviews and discusses the information on sorghum phytochemicals, their processing, and development of food products as well as human health application.
... Policosanols are classified as the group of high molecular weight biologically active long chains of aliphatic primary alcohols between the carbon atoms 22 to 38 (Hwang et al., 2002a(Hwang et al., , b, 2005Vali et al., 2005;Pham et al., 2018), according to their sources of occurrence such as beeswax (Irmak et al., 2005), sugarcane (Irmak et al., 2005), perilla seeds (Adhikari et al., 2006), and cereals (Hwang et al., 2005) like rice Pham et al., 2018), wheat (Irmak et al., 2005Dunford et al., 2010;Pham et al., 2018), sorghum (Hwang et al., 2004;Leguizamón et al., 2009;Pham et al., 2018) as described in the literature. These policosanols phytochemicals are very unique in sorghum grain due to their presence in nonesterified forms (Althwab et al., 2015). ...
... Non Commercial Use (C 32 ) which are available and sold in the markets as nutritional supplements (Hwang et al., 2002b(Hwang et al., , 2005Irmak et al., 2005;Vali et al., 2005). Structure of major policosanols reported in sorghum grain is depicted in Figure 2.10. ...
... Octacosanol (C 28 ) and triacontanol (C 30 ) in sorghum grain do the representation of most predominant policosanols when compare with hexacosanol (C 26 ) and dotriacontanol (C 32 ) (Hwang et al., 2004;Leguizamón et al., 2009). These phytochemicals are gaining more popularity due to their physiological function and beneficial health effects (Figure 2.11) which have been documented in many reports worldwide (Arruzazabala et al., 1994(Arruzazabala et al., , 1996Kabir and Kimura, 1995;Kato et al., 1995;Sttisser et al., 1998;Mas et al., 1999;Castano et al., 2001;Gouni-Berthold and Berthold, 2002;Carr et al., 2005;Vali et al., 2005;Lee et al 2014). Therefore, researchers and scientists are giving more emphasis on its uses in pharmaceutical industries because of the significant presence of policosanols phytochemicals in sorghum grain (Irmak et al., 2005;Dunford et al., 2010). ...
Chapter
With the increase in life expectancy, the prevalence of chronic diseases of the digestive tract, such as peptic ulcers and inflammatory bowel disease, and the metabolic syndrome associated with the current obesity epidemic have increased in the population. High cost and adverse reactions have led to the search for herbal medicines. However, the market is more demanding, and it is necessary to look for safer and more effective alternatives that can prevent and cure these diseases. The two projects carried out by Prof. Wagner Vilegas’ group (“Sustainable Use of Brazilian Biodiversity: Pharmacological and Chemical Prospection on Higher Plants” and “Standardized Extracts for the Treatment of Chronic Diseases”), led to an extensive chemical and pharmacological screening of Brazilian plants with ethnopharmacological indications for the treatment of cancer, ulcers, inflammation, diarrhea too. The first project aimed to investigate plant extracts more thoroughly under the chemical and pharmacological basis, whereas the second project was designed in order to standardize the method of preparationof the extracts, to evaluate the and qualitative and quantitative chemical composition of the extracts according to pharmacopoeial standards, as well as to deeply investigate the mechanistic basis of the biological activities observed. Several alkaloids, flavonoids, terpenoids, saponins, fatty acids, catechins, tannins and phenolic compounds were isolated, identified and/or detected. Pharmacological studies have indicated that some of these medicinal species, commonly used by the population, have proven efficacy for various disorders, with promising results. Therefore, next steps intend the production of pharmaceutical formulations that must have effectiveness and safety of use, which will also facilitate the access to the population to these phytopreparations.
... All filtrates fatty alcohols included were collected and dried over anhydrous sodium sulfate. Fatty alcohols were identified by high-temperature GC 15 . ...
... The combined extract was washed with water to neutral pH, and the ethyl acetate layer was then dried over anhydrous sodium sulfate. The solvent was removed in a vacuum rotary evaporator, and fatty acids were obtained 15 . Fatty acids was converted to fatty acid methyl esters by heating with 2 mL of 5 methanolic sulfuric acid at 70 for 2 h for GC analysis 16 . ...
... and 57.5-69.4 to 62.8-71.6 and 57.3-67.5 . For a given RBW concentration [5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] , the ΔH c was increased from 0.3 24.4 to 2.1 27.9 J/g Table 2 . This means that when the cooling rate is increased, the T m and the T c of RBW oleogles are moved to a lower temperature region and an increase of ΔH c . ...
Article
The main purpose of this paper is to study the microstructure and macroscopic characteristics of rice bran wax (RBW) oleogels at a cooling rate of 1°C/min and 10°C/min by polarized light microscopy, X-ray diffraction, differential scanning calorimetry, texture analyzer, and micro rheometer. The oleogels of soybean oil were prepared by RBW in concentrations of 5%, 7.5%, 10%, 15% and 20% (wt/wt). The results of this study indicated that the concentration of RBW and cooling rates were affected by the crystal size and spatial distribution of these crystals. For the same RBW concentration, oleogels contained smaller crystals when cooled at 10°C/min compared to 1°C/min. And the oleogels obtained at a rate of 10°C/min exhibited a tighter crystal network, lower melting point, harder texture, and energy storage modulus. These results demonstrated the impact of cooling rate on the rheological behavior, nucleation, and crystallization process.
... Rice bran wax is a natural plant wax derived from rice bran, which is an important byproduct of rice bran oil industry of about 0.5-0.6 million metric tons per year in China [9]. The chemical constituents of rice bran wax are mainly mixtures of saturated esters of long chain fatty acids (C 22 and C 24 ) and long chain aliphatic alcohols (C 24 to C 40 ), with C 24 and C 30 being the predominant fatty acid and fatty alcohol, respectively [10,11]. More specifically, Vali et al. [10] reported that crude rice bran wax contains wax esters, rice bran oil, aliphatic aldehydes, fatty alcohols, free fatty acid. ...
... The chemical constituents of rice bran wax are mainly mixtures of saturated esters of long chain fatty acids (C 22 and C 24 ) and long chain aliphatic alcohols (C 24 to C 40 ), with C 24 and C 30 being the predominant fatty acid and fatty alcohol, respectively [10,11]. More specifically, Vali et al. [10] reported that crude rice bran wax contains wax esters, rice bran oil, aliphatic aldehydes, fatty alcohols, free fatty acid. The purified rice bran wax is edible and can serve as a substitute for carnauba wax in most applications due to its relatively high melting point. ...
Article
Full-text available
In this study, crude rice bran wax oil - in - water emulsion (named CRBWE) was prepared by agent-in-water method. The critical factors influencing the sample preparation process were optimized. For instance, the optimum hydrophile-lipophile balance value of compound emulsifier was 12.33–13.40, the content of compound emulsifier was 10 wt%, the emulsification temperature was 70 °C–80 °C, the agitation speed was 200 rpm, and the emulsification time was 30–45 min. The performances as a lubricant of drilling fluid were also evaluated with respect to lubricity, rheology and filtration loss of CRBWE. The results showed that CRBWE had good lubricity and didn't affect the rheological properties of drilling fluid. For example, when it was added into bentonite dispersion at room temperature with the fraction of 1 wt%, the coefficient of friction of bentonite dispersion dramatically decreased to 0.077, and the coefficient of friction reduced rate was greater than 80%. Overall, these findings indicated that CRBWE would have promising applications as environmental friendly lubricant of drilling fluids to reduce torque and drag in petroleum and natural gas drilling.
... Rice bran wax is a natural plant wax derived from rice bran, which is an important byproduct of rice bran oil industry of about 0.5-0.6 million metric tons per year in China [9]. The chemical constituents of rice bran wax are mainly mixtures of saturated esters of long chain fatty acids (C 22 and C 24 ) and long chain aliphatic alcohols (C 24 to C 40 ), with C 24 and C 30 being the predominant fatty acid and fatty alcohol, respectively [10,11]. More specifically, Vali et al. [10] reported that crude rice bran wax contains wax esters, rice bran oil, aliphatic aldehydes, fatty alcohols, free fatty acid. ...
... The chemical constituents of rice bran wax are mainly mixtures of saturated esters of long chain fatty acids (C 22 and C 24 ) and long chain aliphatic alcohols (C 24 to C 40 ), with C 24 and C 30 being the predominant fatty acid and fatty alcohol, respectively [10,11]. More specifically, Vali et al. [10] reported that crude rice bran wax contains wax esters, rice bran oil, aliphatic aldehydes, fatty alcohols, free fatty acid. The purified rice bran wax is edible and can serve as a substitute for carnauba wax in most applications due to its relatively high melting point. ...
Article
Full-text available
Crude rice bran wax oil-in-water emulsion (named CRBWE) was first fabricated by agent-in-water method. • CRBWE is nontoxic and biodegradable. • CRBWE exhibited good lubricity. • CRBWE has promising application as environmental friendly lubricant to reduce torque and drag in petroleum drilling. A R T I C L E I N F O Keywords: Emulsion-type lubricant Crude rice bran wax Lubricity Biodegradable Water-based drilling fluids A B S T R A C T In this study, crude rice bran wax oil-in-water emulsion (named CRBWE) was prepared by agent-in-water method. The critical factors influencing the sample preparation process were optimized. For instance, the optimum hydrophile-lipophile balance value of compound emulsifier was 12.33-13.40, the content of compound emulsifier was 10 wt%, the emulsification temperature was 70 °C-80 °C, the agitation speed was 200 rpm, and the emulsification time was 30-45 min. The performances as a lubricant of drilling fluid were also evaluated with respect to lubricity, rheology and filtration loss of CRBWE. The results showed that CRBWE had good lubricity and didn't affect the rheological properties of drilling fluid. For example, when it was added into bentonite dispersion at room temperature with the fraction of 1 wt%, the coefficient of friction of bentonite dispersion dramatically decreased to 0.077, and the coefficient of friction reduced rate was greater than 80%. Overall, these findings indicated that CRBWE would have promising applications as environmental friendly lubricant of drilling fluids to reduce torque and drag in petroleum and natural gas drilling.
... The crude wax was refined in a small scale experimental setup (Vali et al., 2005) and utilized for preparing coating emulsions. ...
... The vial was capped and placed at −20℃ until it undergoes LC-MS analysis. The sample was evaporated using nitrogen and was re-dissolved with 5 ml of methanol (LCMS grade) followed by purification using solid-phase extraction cartridge for the LCMS/ MS analysis (Vali et al., 2005). ...
Article
The edible coating is considered as one of the most‐effective and safer ways to prolong the shelf‐stability of the horticultural crops. Utilization of rice bran wax (RBW) as a coating substrate can be an excellent shelf‐life extension strategy by transforming secondary by‐product from rice processing into a useful coating substrate. This research was an attempt to use RBW as an edible coating and its effects on the shelf‐life extension of Marutham CO3 variety tomatoes. Crude RBW refined in laboratory‐scale was undergone for free fatty acid profile analysis and found that contains 18 health‐beneficial free fatty acids. RBW was made into an emulsion with different concentrations used for coating the tomatoes. Physiological loss weight, lycopene content, TSS, firmness, respiration rate, SEM structure and thickness of the coatings were analyzed and observed that 10% emulsion coated tomatoes had shown a shelf‐life of 27 days, compared to 18 days of the control samples.
... Wax is the term used to refer to any product that contains fatty materials obtained from plants, animal, marine, or mineral. It is an ester of a long chain carboxylic acid and long chain alcohol (Vali et al., 2005). Wax is considered necessary because of its characteristics. ...
... In previous work, rice bran wax with the purity of 99 % was isolated from crude rice bran oil by refluxing using hexane, isopropanol, and bleaching with NaBH4 (Vali et al., 2005). Gunawan et al. (2006) succeeded in obtaining rice bran wax with the purity of 99% (yield 1.4 %) from rice bran oil using modified soxhlet extraction and followed by wax crystallization in cold acetone for 24 h. ...
Article
Full-text available
Calophyllum inophyllum is one of the most notable mangrove species that grows a lot in the coastal areas of the Indonesian archipelago. Despite its long lifespan (50 years) and abundant seed oil production, this plant has not been utilized optimally. Wax is reported as a constituent of C. inophyllum seed oil, but the quantity has not been discovered yet. Wax has been commonly used as ingredient in coating, cosmetic, food, and pharmaceutical industries. The aims of this work were to separate wax from C. inophyllum seed oil in high purity and investigate the effects of crude C. inophyllum to silica gel mass ratio and the stages number on wax isolation. Silica gel was employed to adsorb crude C. inophyllum seed oil. Mass ratios of C. inophyllum seed oil to silica gel used in this work were 1:4, 1:2, and 1:1 (g/g). After that, the seed oil adsorbed onto silica gel was extracted by soxhlet extraction with hexane as the solvent. Wax was separated by putting the hexane extract in cold storage at 4 ºC for 24 h. Furthermore, wax obtained was analyzed by High-Temperature Gas Chromatography (HT-GC) and confirmed by Thin-Layer Chromatography (TLC). It was found that wax (purity 93.2 % and yield 0.4 %) was best isolated by employing two-stage of adsorption-extraction, with crude C. inophyllum seed oil to silica gel mass ratio of 1:1 (g/g), followed by crystallization in cold acetone for 24 h. Moreover, wax content in crude C. inophyllum seed oil was 0.43%.
... The presence of resinous matter is majorly responsible for the dark reddish brown colour and characteristic odour of crude RBW [67]. Shaik Ramjan Vali et al. [68] have outlined a process for purifying crude wax and the successive preparation of food grade RBW. The potential applications of RBW can be realized in pharmaceutical, food, cosmetic, polymer and leather industries [69,70]. ...
... TG and DTG curves of Fig. 1A shows that almost all the sample was burned at the end of the assay. The mineral content, related to the presence of inorganic non-volatile compounds, was higher than the one reported for food-grade rice bran wax (0.06%) (Ramjan et al., 2005) and beeswax (0.00246%) (Bernal et al., 2005). Five peaks corresponding to weight losses at 148. 54, 184.93, 338.51, 428.97, and 539.63°C were observed in the DTG curve (Fig. 1A). ...
Article
Citrus wax is a waste generated during the purification process of the citrus essential oil. A lot of citrus wax wastes are globally produced, despite this, its composition and properties are not well known. Here we present comprehensive results proving the chemical composition and the physical properties of citrus wax. Additionally, our study provides the basis for obtaining value-added products from citrus wax wastes. The qualitative/quantitative analysis revealed the presence of different compounds, which range from flavonoids, saponins, carbohydrates, unsaturated compounds, phenolic hydroxyls, and long-chain fatty acid esters. Given that citrus wax is a source of many bioactive compounds, they were preferably extracted with ethanol. The ethanolic extracts demonstrated the presence in citrus wax of different bioactives, such as 5–5′-dehydrodiferulic acid, 3,7-dimethylquercetin, 5,6-dihydroxy-7,8,3′,4′-tetramethoxyflavone, tangeretin, and limonene. After the extraction of bioactives from citrus wax, a washed waxy material with high content of long-chain fatty acid esters was obtained. It was shown that this washed wax can be used for the production of biodiesel. The transesterification reactions in acid media was the preferred process because higher content of fatty acid methyl esters (such as hexadecanoic acid methyl ester and 9,12-octadecadienoic acid (Z,Z)-, methyl ester) were obtained. Currently, citrus wax does not have any industrial application, here we shown that under the concept of waste biorefinery, the citrus wax wastes are useful sources for producing value-added products such as bioactive compounds and biodiesel.
... Waxes are esters of long-chain alcohols and fatty acids. This definition comprises a broad class of lipid substances, that may include other functional groups, such as ketones, aldehydes and aromatic compounds 1,2 . Among the different types of waxes, those derived from plants have received an increasing interest because of the growing demand of biomaterials. ...
Article
This study aims to evaluate the effect of vegetable waxes on the kinetic of lipid oxidation of linseed oil. Apples and orange waxes were obtained by supercritical carbon dioxide. The capacity of waxes to inhibit or retard the oxidation of linseed oil was determined by isothermal calorimetry at 298 K. The results show that waxes were able to slow down linseed oil autoxidation, with apple waxes being more active than orange waxes. However, such activity was visible only at relatively high concentrations (> 1 % of waxes), greatly higher than the concentration used with radical chain breakers like BHT (0.2 %). The inhibition activity was explained by considering three different mechanisms, respectively, (1) residual polyphenol content in the wax, (2) high termination rate of the radical chain process, (3) physical hindrance of the oxidation process by change of viscosity. All these mechanisms were possible, although the latter seemed to be the most important. Finally, significance of waxes to inhibit lipid autoxidation was determined by testing their inhibition activity in cooperation with primary antioxidants. Mixture of waxes with BHA, ethoxyquin and α-tocopherol showed higher rate of inhibition than when present individually. This suggested a strong cooperative radical scavenging activity, whose beneficial effect might pave the way to the formulation of novel functional ingredients.
... Rice (Oryza sativa) bran wax (RBW) as a byproduct of rice bran oil refining can be used as a good lipid source to fulfill most of the requirements expected in food, cosmetics, and pharmaceutical industries. Considering physical features, RBW is similar to carnauba wax (CRW; Vali, Ju, Kaimal, & Chern, 2005;Zhang et al., 2019). In terms of wax composition, wax esters (73.4% to 93.5%) are the main component of RBW followed by long-chain free fatty acids and free fatty alcohols, contributing to its high melting point (81 to 82 • C). ...
Article
The development of lipid‐based delivery systems has attracted much attention over the last years and a wide variety of strategies and formulations are currently available to encapsulate, protect, and target delivery of bioactive and functional lipophilic constituents within the food and pharmaceutical industries. Waxes are crystalline lipid material, consisting of a complex mixture of long‐chain fatty acids and fatty alcohols, hydrocarbons, aldehydes, and ketones and show great promises as constituents of carrier systems. Most of waxes are classified under food‐grade category and show high availability at a low cost. This review article has provided a comprehensive summary of research on major carriers containing wax as one of the main constituents, including solid lipid nanoparticles, nanostructured lipid carriers, oleogels, and Pickering emulsions, with a focus on their food applications. The physical and chemical nature of natural waxes are described in the first while the second part deals with the structure, formulation, main methods of preparation, characterization, and finally utilization of each type of wax‐based delivery system for specific food applications.
... Processes for the separation and purification of food grade wax (Buffa, 1976;Vali et al., 2005), fatty acid steryl esters (Gunawan et al., 2006), γoryzanol (Arumughan et al., 2004;, and tocochromanols (Rajam et al., 2005) from rice bran have been developed. Preparations of phytic acid from rice bran were also proposed by previous works (Wu, 1998;Showa, 1985). ...
Chapter
Rice (Oryza sativa L.) is one of the major staple foods in the world, including in Brazil. Rice cultivation is carried out, especially, in two systems: rainfed and irrigated. The irrigated rice is responsible for the major part of rice production, however is the most environmental impactful. Rice production in Brazil has been growing steadily over the years, with an increase of approximately 25% in volume in the last three decades. Being chemical the main method of weed control in rice, this is one of the major difficulties in rice production, mainly due to cases of weed resistance to many herbicides. Due to the problems encountered for the control of red-rice and black-rice, alternative rice cultivars have been launched, as the case of the Clearfield® and Liberty Link® rice cultivars. The development of genetically modified rice allowed the selective management of the main weeds of rice (red and black rice). However, there are well reported cases of genetic flow between cultivated rice and wild rice, compromising the efficiency of weed control. The use of new technologies, with no other control method but the chemical, will not be able to minimize the harmful effects of weeds to rice, being necessary to develop integrated control strategies. This chapter will discuss the main strategies in weed control in rice, as the impacts of rice cultivation in the environment and discuss the genetically modified rice cultivars on weed control.
... Processes for the separation and purification of food grade wax (Buffa, 1976;Vali et al., 2005), fatty acid steryl esters (Gunawan et al., 2006), γoryzanol (Arumughan et al., 2004;, and tocochromanols (Rajam et al., 2005) from rice bran have been developed. Preparations of phytic acid from rice bran were also proposed by previous works (Wu, 1998;Showa, 1985). ...
Chapter
In Cameroon as in many parts of the world, ruminant production plays an important role in the predominantly agricultural economy, especially in mixed animal-crop production systems. In addition to providing meat and milk for human consumption, these animals provide draft power and manure for crop production. The crop residues constitute the main feed of these animals. Land scarum and the trend of sustainable agricultural development in some highly populated zones of Cameroon like the West Region necessitate better utilisation of crop residues in general and rice straw in particular for ruminant feeding. Rice straw is rich in polysaccharides and has a high lignin and silica content, limiting voluntary intake and reducing degradability by rumen microbes. The treatment of rice straw can improve its quality and digestibility and enhance protein content. Suitable treatment techniques in combination with nutrient supplementation could result in improved utilisation of rice straw with better benefits. In recent years, biological treatments have been investigated for improvement in nutritional value of rice straw. The use of ligninolytic fungi and their extracellular ligninolytic enzymes for treatment of rice straw results in degrading the cellulose and hemicelluloses contents which improve its nutritional value. The use of fungi and enzyme treatments is expected to be a practical, cost-effective and environmental-friendly approach for enhancing the nutritive value and digestibility of rice straw. The treatment of rice straw could therefore be a good potential as feed for ruminants.
... The major impurity in the defatted wax was the dark brown resinous matter that can be removed by bleaching with sodium borohydride in isopropanol to yield pale yellow, odorless wax with purity higher than 99 and with melting point of 80 -83 . The resinous matter is a mixture of aliphatic aldehydes, fatty alcohols, and fatty acids 16 . ...
Article
Rice bran oil (RBO) is healthy gift generously given by nature to mankind. RBO is obtained from rice husk, a byproduct of rice milling industry and is gaining lot of importance as cooking oil due to presence of important micronutrient, gamma oryzanol. Its high smoke point is beneficial for its use for frying and deep frying of food stuff. It is popular because of balanced fatty acid profile (most ideal ratio of saturated, monounsaturated and polyunsaturated fatty acids), antioxidant capacity, and cholesterollowering abilities. Rice bran wax which is secondary by-product obtained as tank settling from RBO is used as a substitute for carnauba wax in cosmetics, confectionery, shoe creams etc. It can be also used as a source for fatty acid and fatty alcohol. The article is intended to highlight for the importance of RBO and its applications.
... Therefore, rice bran could probably be a major source of ceramide. Rice bran has been generally processed by using a cold-press method to obtain crude oil before precipitating at low temperature or winterization process to precipitate rice bran wax, which contains fatty acid, fatty alcohol and ester (Vali et al., 2005;Kim, 2008). The non-precipitated fraction is dewaxed rice bran oil. ...
Article
Ceramide is a sphingolipid, which provides health benefits. Gas chromatography coupled with flame ionized detector (GC-FID) was developed for targeted analysis of hydrolyzed ceramide in color rice and by-products. Method validation was done by means of linearity, repeatability and % recovery. R2 of 0.99 by means of linearity equation of the method was obtained. The recovery was in the range of 69.85 – 108.73% with RSD of normalized peak area lower than 10%. Hydrolyzed ceramide was found in unpolished rice, both glutinous and non-glutinous rice and its by-products including, defatted rice bran, rice bran wax and rice bran oil. The relationship between varieties of rice color and ceramide content was classified using principal component analysis (PCA) into 2 groups, including dark and pale color rice group. The highest levels of hydrolyzed ceramide as 21.11±0.02 mg/100 g was found in Mali Nil Surin (MNS), black non-glutinous rice. Whereas white non-glutinous rice named Seebukantang (SBK) contained the lowest content of hydrolyzed ceramide as 12.69±0.03 mg/100 g. The amount of ceramide in by-products found in defatted rice bran, rice bran oil and rice bran wax were 17.43±0.38, 14.67±0.16 and 12.54±0.41 mg/100 g, respectively.
... As the temperature within an extraction system increases, a decrease Table 2 Soxhlet extraction of waxes in literature. Literature Biomass Solvent Technique ( Sun and Sun, 2001) Barley straw Various solvents tolueneeethanol (2: 1, v/v), chloroform, MTBE, dichloromethane and Hexane/acetone Soxhlet extraction ( Xiao et al., 2001) Rice straw Various solvents tolueneeethanol (2: 1, v/v), chloroform, petroleum ether, dichloromethane and hexane Soxhlet extraction ( Nuissier et al., 2002) Sugarcane waxes from rum factory wastes Cyclohexane Soxhlet extraction ( Sun and Tompkinson, 2003) Wheat straw Various solvents tolueneeethanol (2: 1, v/v), toluene-ethanol-methanol (1:1:1 v/v), MTBE, chloroform-methanol (2:1, v/v) Soxhlet extraction (Guti errez and del Río, 2005) Pitch deposits from hemp fibre Acetone Soxhlet extraction ( Vali et al., 2005) Rice bran Hexane Refluxed in solvent ( Wang et al., 2005) Grain Sorgum DDG Hexane Soxhlet extraction ( Andr as et al., 2005) Okra seeds Hexane/ethanol Soxhlet extraction ( Morrison et al., 2006) Flax/linseed Hexane Soxhlet extraction ( Zhao et al., 2007) Rice, wheat straw and corn stalk Various solvents petroleum ether, chloroform, toluene, alcohol, acetone, heptane and toluene/ alcohol Soxhlet extraction ( Athukorala et al., 2009) Flax straw Hexane Soxhlet extraction ( Villaverde et al., 2009) Miscanthus giganteus stalk Dichloromethane Soxhlet extraction ( Villaverde et al., 2010) Miscanthus giganteus bark Dichloromethane Soxhlet extraction ( Athukorala and Mazza, 2010) Triticale straw Hexane Soxhlet extraction ( Marques et al., 2010) Flax, hemp, sisal and abaca fibres Acetone Soxhlet extraction ( Naik et al., 2010) Wheat straw, barley straw, pinewood, flax straw and Timothy grass Hexane Soxhlet extraction ( Asikin et al., 2012) Sugarcane rinds and stalks Hexane and methanol (20:1) Soxhlet extraction ( Sin et al., 2014) Wheat straw Hexane Soxhlet extraction ( Backlund et al., 2014) Pinus contorta stumpwood, branches, bark, cones and needles Hexane Soxhlet extraction ( Attard et al., 2015b) Sugarcane rind, leaves and bagasse Hexane Soxhlet extraction ...
Article
The decline in petrochemical wax supply coupled with the ever-growing demand for bio-products means that the development of a sustainable process to renewably sourced waxes is paramount. This review focuses on recent advances in supercritical extraction as a clean efficient process for extracting waxes from waste biomass as a part of a holistic biorefinery. The use of supercritical carbon dioxide leads to reductions in solvent waste and leaves no solvent residues meaning that the biomass can further processed without the need for energy-intensive solvent removal steps. This technology crucially improves the downstream conversion of residual cellulosic biomass for the sustainable production of sugars, consumer products and biofuels (up to a 40% increase in ethanol production) leading to higher energy efficiencies and higher economic returns. Supercritical carbon dioxide extraction is not only an important technology for the cleaner production of waxes, it is a sustainable pre-treatment of biomass as part of an integrated holistic biorefinery and significantly, it can improve the safety of products, e.g. less off gassing of wood pellets.
... The free fatty acids formed bring about a reduction in pH, rancid flavour and soapy taste which render the rice bran unsuitable for human consumption [27,28].An increase in the free fatty acid was also observed by Ramezanzadeh et al. [29] within hours and reached 5-7% within the first 24 h and 40% within 15 days [30]. Rice bran oils with FFA >5% are considered unfit for human consumption [31]. ...
Article
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Rice (Oryza sativa) is the world's single most important crop and a primary food source for over half of the world's population. Before consumption, rice is usually milled and sometimes parboiled before milling. Rice bran which is a by-product of rice milling, has been reckoned as a potential source of edible oil. This oil is widely used in pharmaceutical, food and chemical industries due to its unique properties and high medicinal value. In this study, oil was extracted from two varieties (Tox and Nerika) of raw and parboiled Ndop rice bran and characterized for oil yield and quality indices. The quality indices of the extracted oil (acid value, iodine value, peroxide value, saponification value and thiobarbituric acid value) were determined using French Norm for fat and oil (AFNOR). Results revealed that bran from Tox variety produced more oil (12.75-13.75% v/w) than Nerika (5-6% v/w). The Tox parboiled variety of Ndop rice bran yielded the highest percentage (13.75%v/w) of oil. In both varieties, parboiling slightly increased the percentage oil yield. The free fatty acid (0.42-0.70%), iodine value (95.40-101.30gI 2 /100g), peroxide value (7.35-2.172meq/kg) and thiobarbituric acid value (0.023-0.040) were within the acceptable ranges of Codex Alimantarius. Saponification value of oil samples ranged between 144.93 to 168.85mg/g of oils. Parboiling improved the quality of Ndop rice bran oil by decreasing the acid, peroxide and thiobarbituric acid values, but had no significant effect on the iodine value. The fatty acid composition of the oils from the two varieties of rice bran oil shown that rice bran oil is an unsaturated oil, with unsaturated fatty constituents ranging between 73.44 and 74.33% and the saturated counterparts between 25.66 and 27.17%. Rice Bran Oils were rich in monounsaturated fatty acids 42.62-43.44%, and also polyunsaturated fatty acids between 30.7 and 30.88%. The saturated, mono-unsaturated and polyunsaturated fatty acids that were more predominant in the oil were palmitic, oleic and linoleic acids respectively. For the n-3 PUFA family, the highest proportions were found in ToxNon Parboiled and Nerika Non Parboiled (30.88% and 4.37% respectively. The levels PUFA/SFA obtained here were greater than 0.45. Artherogenic index (AI) is proposed to evaluate risky factors that are implicated in coronary heart disease development ; It was < 0.4 in the investigated rice bran oils, owing to the high n-6 PUFA contents and low n-3 ratios. Oven drying of the bran provoked changes on the rice oil. Ndop rice bran is therefore a good source of edible oil whose quality can be improved by parboiling and oven drying.
... Even within one type of wax, the chemical composition C.D. Doan et al. Innovative Food Science and Emerging Technologies 45 (2018) 42-52 can vary greatly depending on the growing conditions, the maturity stage and the geographic origin of the plant/animal from which the waxes are extracted (Asikin et al., 2012;Huynh, Do, Kasim, & Ju, 2011;Vali et al., 2005). A typical chemical composition of some natural waxes is presented in Table 1. ...
Article
In recent years, wax-based oleogelation has appeared as a new and effective strategy to structure liquid oil into soft, solid-like systems, which can be exploited as alternatives for trans- and/or saturated lipidic hardstocks in the production of lipid-based food products. Waxes are crystalline gelators, consisting of a mixture of straight-chain alkanes, long-chain fatty acids, long-chain fatty alcohols, wax esters, aldehydes, ketones, glycerol esters or di-esters. Wax-based gelation arises from the crystallization of wax particles. Tuning the preparation conditions such as cooling rate, shear rate and setting temperature can alter the crystallization and gelation of natural waxes in liquid oil. A better fundamental understanding on wax-based oleogelation is therefore important to control the quality of food products, in which these oleogels could act as structuring agents. In the food industry, wax-based oleogels can be utilized to partially or fully replace the trans- and/or saturated fats in fat-based food formulations such as shortening, margarine, confectionery products, ice-cream, and whipped-cream. Furthermore, oil migration can be prevented by using wax crystals to capture the free liquid oil within a fat-based confectionery filling. The scope of this review is to provide a concise insight into structuring liquid oil using natural waxes, with the emphasis on different internal and external factors affecting the physicochemical properties of wax-based oleogels. The innovative food applications of wax-based oleogels are also discussed in details. Industrial relevance Wax-based oleogelation has been emerged as a potential alternative to conventional oil structuring. The gelling behavior of natural waxes in liquid oils is governed by the polarity of the solvents, and by the wax crystal morphologies, which are determined by the nature and chain length of the chemical components present in waxes. In addition, the gelling behavior of wax-based oleogels can be tuned by altering the cooling and shear rates, and by changing the time and temperature of cooling. These factors strongly influence the physicochemical properties as well as the storage stability of wax-based oleogels. In addition, the application of wax-based oleogel in food formulations has encountered some technical challenges due to the incompatibility between oleogels and saturated fats, and due to the insufficient amount of solid content provided by waxes. With regard to the sensorial aspect, the waxy mouthfeel might be an obstacle restricting the acceptance of wax-based products in food markets. This review therefore provides a concise overview relating to the internal (chemical composition of natural waxes, type and polarity of solvents) and external factors (cooling rate, shear rate, storage time, and co-structuring) affecting the crystallization and gelation of wax-based oleogels, as well as their potential application in producing low-saturated fat products in food industry.
... It is white to yellowish in color and can be made available in flakes form. It can be obtain by dewaxing step in refinery process 14 . It can be again separated from oil using filtration and centrifuge process 15 . ...
Article
The present work deals with comparison of microwave assisted extraction to that of conventional solvent extraction for the extraction of rice bran oil (RBO); focusing on extraction yield and oil composition. Microwave assisted extraction act as a green process over other method and proved that it is effective method for extraction of oil. The investigation also focuses on the study of functional group and component present in oil. Natural antioxidant component; its activity was confirmed by DPPH assay. The oryzanol content was also determined by measuring the optical density of the sample at 315 nm in n-heptane using UV visible spectrophotometer.
... The major policosanol of wax was triacontanol (C30) (51.6%), followed by hexacosanol (C26) (18.5%) and octacosanol (C28) (15.9%) while those of RBO was octacosanol (33.6%) and tetracosanol (C24) (32.2%). Vali et al. (2005) indicated that predominant fatty alcohol of rice bran wax was tetracosanol (C24) and triacontanol (C30), while Ishaka et al. (2014) reported octacosanol (C28) and hexacosanol (C26) were the main policosanol of rice bran wax. Kim et al. (2014) studied on PC content in rice bran and reported that the octacosanol (C28) was the predominant component (46.4%), followed by triacontanol (C30) (31.6%), and tetracosanol (C24) (24.3%), which was a similar result reported by Cravotto et al. (2004). ...
Article
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Sugarcane and rice bran are the most important sources of commercial policosanol (PC) wax which exhibits a cholesterol lowering bioactivity. Both defatted rice bran (DRB) as agricultural waste and rice bran oil (RBO) retain a varying but significant amount of PC wax. Non-centrifugal cane sugar (NCS) has been consumed worldwide, and possesses various health benefits. It is mostly produced in hardened block form, which is not convenient for use compared with granular form. We aimed to increase PC contents of the granular sugar by adding wax extracted from DRB and RBO and to investigate the toxicity of the products. The results showed that the total PC contents including long chain aldehyde of products were increased to the maximum level of 147.97 mg/100 g. DRB is promising source of policosanol (6,044.7 mg/100 g). The main volatile components of developed sugar product was aldehyde and alcohol compounds. The 28 day toxicity evaluations of the developed sugar revealed no adverse effects.
... Cumulating all symmetries at equal CN, this resulted in relative frequencies of the WEs in a range between 34 and 56 carbon atoms. A publication by Vali et al. (2005) reports the WE composition of five different rice bran waxes as well as the chain lengths of the FaOH and FA residues of the saponified WEs. This was used to validate the assumption of statistical recombination of FA and FaOH moieties to calculate the WE distribution of a natural wax. ...
Article
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Current research on wax‐based oleogels indicates wax esters to be the key component in many natural waxes. This necessitates understanding the properties of pure wax esters to unravel the gelling mechanism in wax‐based oleogels. Therefore, available literature data on pure wax esters is summarized and critically reviewed. The detailed analysis of the pre‐existing data on crystallographic (SAXS) and thermal properties, facilitates the interpretation of subsequently performed experiments: Specific wax esters with different carbon numbers and symmetries were studied as such and in oleogels formed in combination with medium chained triglyceride oil at inclusion levels of 10% (w/w). They were characterized regarding their thermal (differential scanning calorimetry [DSC]) and viscoelastic (oscillatory rheology) behavior. It is found that all observations concerning pure wax esters behave systematically, linking molecular makeup, crystal structure, and behavior. The experimental study of oleogels structured by four different binary mixtures of wax esters revealed that substantial chain length differences induce separate crystallization (CN30 + 36 and CN30 + 42). Mixtures of wax esters with only limited chain length difference (≤ 2 carbon atoms) reconfirmed earlier speculations on mixing behavior and crystal structure. Applying mixtures of wax esters only differing in their position of the ester bond (CN36 [14_22] + CN36 [22_14]) indicated ideal mixing behavior in the solid phase of the gels. Surprisingly, the data revealed that additional thermal events occur at specific mixing ratios, predominantly at 1:1 (w/w). Their supposed relation to compound formation certainly needs further confirmation. Rheological analysis confirmed that sequential crystallization results in highest firmness values for the systems studied.
... Processes for the separation and purification of food grade wax (Buffa, 1976;Vali et al., 2005), fatty acid steryl esters (Gunawan et al., 2006), γoryzanol (Arumughan et al., 2004;, and tocochromanols (Rajam et al., 2005) from rice bran have been developed. Preparations of phytic acid from rice bran were also proposed by previous works (Wu, 1998;Showa, 1985). ...
Chapter
Rice, a staple food widely consumed in Asian countries, is classified according to its morphological appearance, i.e., shape, texture, size, and color. As of January 2017, the International Rice Genebank has stored more than 100,000 rice accessions. Oryza sativa and Oryza glaberrima are two types of rice that are cultivated on a large scale. Each is different in its nutritional content. While its main constituent is carbohydrates, rice also has dietary fibers, vitamins, fats, and proteins. Different varieties of rice are used in signature cuisines worldwide. As rice is an agricultural product in high demand, much research has been conducted to improve the quality of the crop as well as ensure its continuous supply. Post-harvest losses and the need for appropriate handling have been identified as major challenges. Measures should be taken to ensure that the quality of harvested rice does not deteriorate as this will affect its supply for consumption. The quality of rice presented to the consumer can be affected by factors such as post-harvest diseases, storage, and packaging. Advancements in biotechnology, especially in genetic modification, will help to increase rice production to meet global demand, as well as to improve the quality of the rice grain.
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The pyrolysis characteristic of rice bran wax (RBW) and its bio-fuel oil were analyzed. TG, Py-GC-MS, TG-MS, FTIR, 1 H NMR and 13 C NMR were all carried out to analysis RBW pyrolysis characteristic and bio-fuel oil characteristic. TG results showed that RBW pyrolysis temperature was mainly in the temperature range of 350 °C-450 °C. The mean activation energy values calculated from KAS method and FWO method was 106.15 kJ/mol and 115.72 kJ/mol, respectively. The TG-MS results showed that main gas products were alkane and olefins. The Py-GC-MS also found the mainly components of pyrolysis products were alkane and alkene. The 1 H NMR, 13 C NMR and FTIR experiments were also carried out to confirm the component of bio-fuel oil. The results found that the main components of pyrolysis products were alkane and alkene. The bio-fuel oil properties were also analyzed. The acid value was very low. It was about 10 mg(KOH)/g. And the coke was found. The yield was about 8%. According to above results, it was confirmed that RBW maybe was a good bio-resource to obtain long carbon chain bio-fuel oil.
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Rice bran wax (RBW)–rice bran oil (RBO) oleogel is an alternative structured fat used to replace saturated and trans fats. Our study investigated the effects of the RBW crystal network structure of oleogel on lipid digestibility compared with margarine (MG) and beef tallow. After high-fat diet feeding for 4 weeks, the RBW–RBO oleogel group showed a decrease in adipose tissue accumulation, triacylglycerol (TAG) levels in serum and liver and total cholesterol (TC) in liver, an increase in excreted TAG, TC and bile acid contents in faeces, and reduced alanine aminotransferase and total bilirubin levels compared with the control and MG groups. Oleogel decreased TAG levels by around 30% in serum and liver and increased excreted TAG levels by 30% in faeces compared with rats fed the individual components (RBW and RBO). These results suggest that the gel network is a key contributor to the decrease in lipid digestibility.
Chapter
Rice is one of the most common staple foods that people usually consume around the world. By-products from the rice milling process have high amounts of nutrients when compared to white rice itself. Rice straw, rice hull, broken rice, rice germ, rice bran, rice bran oil and wax are the by-products from the rice industry. These by-products usually have basic applications in their original form, but now can be used as raw materials for different value-added research or in food applications with functional properties. Rice by-products not only contain various types of functional components, but also contain dietary fiber. The fiber can be mostly found in rice hull and the types of fiber present include cellulose, hemicellulose, lignin and hydrated silica. Because of the high fiber content in rice hull and rice bran, they are used as ingredients by the bakery industries to increase the fiber content and improve the nutrition of bakery products.
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In this study, a comparison of the wax extraction process from rice, sorghum and wheat using liquid nitrogen was done respect to traditional solvent extraction method using n-hexane. For this purpose, these cereals were immersed in liquid nitrogen (1 to 4 cycles with different time intervals and different rest times between cycles). The results showed that waxes could be extracted by liquid nitrogen, but with a lower yield. When compared to n-hexane extraction method, the extracted amounts of waxes with liquid nitrogen were 5, 7.5 and 9.3 times lower, but the extraction times were 2.3, 5.5 and 11.25 times shorter for wheat, rice and sorghum, respectively. No residue was left in wax-like materials extracted with liquid nitrogen. While SEM depicted that the outer layer of waxes on the grains could be extracted by liquid nitrogen, GC-MS and GC-FID showed that the extracted waxes had similar compositions in both extraction methods. These results could point out a novel environmental-friendly method to extract waxes from cereals that could be useful for certain applications.
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Structural and rheological properties of oleogels consisting of 0.5–25 wt% rice bran wax (RBX) in rice bran oil (RBO) were explored. RBX was an efficient, thermoreversible oleogelator capable of structuring RBO at concentrations as low as 0.5 wt% RBX. A qualitative temperature-composition phase diagram showed that oleogels containing higher concentrations of RBX were expectedly the most resistant to melting. In oleogels at higher RBX concentrations, polarized light microscopy revealed the presence of a network of interlinked, long aspect ratio wax crystal needles up to 50 μm long. Upon heating, RBX crystals did not undergo any structural transition, based on the constant short spacings at ~ 4.16 and ~ 3.73 Å, indicative of an orthorhombic subcell, and d001 long spacing at 74–76 Å that persisted until RBX fusion. This long spacing was ascribed to the presence of wax esters consisting of long-chain saturated fatty acids (C24 and C22) esterified to C28 – C34 saturated fatty alcohols. During cooling from 90 to 20 °C, the increase in oleogel viscosity resulting from the RBX liquid-solid phase transition was corroborated by DSC-based crystallization onset and enthalpy data. Similarly, elastic moduli and hardness both rose with increasing RBX concentration. This study, which demonstrated that RBX can structure RBO with distinct concentration-dependent properties, serves as the foundation for the development of oleogel-based approaches to saturated and trans fats replacement in processed foods.
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Bleached rice bran wax (BRX), which is a by-product of rice bran oil purification, was used in this study. Bleached rice bran wax organogels (BRXO) were produced by mixing rice bran oil with BRX at 3%, 5%, 7% and 9 wt%. The crystal morphology and polymorphisms of BRXO were similar to bulk wax. BRXO crystal morphology is needle-like and fibrous. Crystalline BRXO has a structure with an orthorhombic sub-cell. The DSC thermographs showed two melting and crystallization profiles. BRXO formed gels at 5, 7 and 9 wt%. The gelation time decreased with an increase in BRX levels. The oil-binding capacity of BRXO at 7 and 9% BRX levels was higher than that at 98%. Texture parameters (firmness, hardness and adhesiveness), thermal behaviours (melting and crystallization behaviour) and SFC varied significantly with BRX level. The water-in-oil emulsion was prepared by using 9% BRXO (EO9). EO9 showed good stability compared to emulsion without the addition of organogels (E). Margarine in cookies was replaced with EO9. The hardness and colour of cookie dough and cookies were significantly affected by level of replacement, while the diameter, width, and spread factor were not significantly different. The results showed that BRX has feasibility for producing the organogels and water-in-oil emulsions, which have potential for margarine replacement in cookies.
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Recently, a number of publications demonstrated the successful applications of oleogels (OG) (liquid oils gelled through organogelators) in food products. Although many highlighted the health benefits of OG, potential negative impacts of thermal processing during oleogelation on nutrition and flavor quality of the OG‐based food are not fully studied. Hence, in this study, an oleogel‐cream‐cheese (OCC) product was formulated and the effects of OG processing on the oil's oxidative stability and the tocopherol content were investigated. The OG system used in the cheese product was prepared with high‐oleic soybean oil (HOSO) and rice bran wax. An ungelled cream‐cheese sample (UGCC) and two commercial cream‐cheese products were used as controls. Although high‐performance liquid chromatography data analysis showed a lower total tocopherol content in OG samples compared to HOSO, the samples’ α‐tocopherol content remained comparable. No significant differences were observed between the total tocopherol contents of OCC and UGCC cheese products, and the amount of all three‐tocopherol isomers remained constant during 14 days of storage. Although oxidation analysis showed more volatile compounds in OG samples compared to HOSO, there was only a minor difference in the volatile content between the OCC and UGCC samples. The results show minimal degradation of vegetable OG due to the thermal processing and storage that may help their potential application in dairy products.
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The drastic increase in the utilization and conversion of biomass has been an effect of sustainability and circular economy in the food processing sector. Rice bran wax (RBW), an intermediate by-product of rice bran oil refining industries, has been one of the underutilized waste materials. The FT-IR analysis showed that RBW contains many similar compounds to that of beeswax (BW) and carnauba wax (CW). The DSC thermographs showed melting and crystallization temperatures of RBW as 78.55 and 73.43°C, respectively, lesser than CW and more than BW. The peak profiling of XRD diffractographs has shown full-width at half-maximum of CW and RBW as 0.61 and 0.45, respectively, indicating distortion in crystal formation. The sequential extracts of RBW in hexane, dichloromethane, and ethylacetate have shown antimicrobial activity against E. coli and S. typhi. The research provides a baseline for extraction and separation of specialty compounds from RBW for by-product utilization.
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Black cumin is a strong aromatic seed which can be used as a nutraceutical or medicinal food. Our aim was to evaluate the fatty acid profile and oxidative stability of black cumin seed (BCS) oil as well as the antioxidant activity of water–methanol extract of BCS compared with BHT. In fact, it was going to understand what kind of fatty acids exist in BCS oil and whether is it possible to apply BCS extract as a natural antioxidant or not. The physicochemical properties of BCS oil included an iodine value of 105.17 g/100 g oil, a PV of 11.88 meq/kg, an oxidative stability index of 16.48 h, viscosity of 21.3 mPas, and a refractive index of 1.45. BCS oil contained more than 79% unsaturated fatty acids. Its saturated fatty acids were composed mainly of palmitic acid (8.38%) and stearic acid (2.26%). The BCS extract contained 955.77 mg/kg total phenolics. In a DPPH assay, the IC50 of the BCS extract was measured as 104.76 mg/mL, while for BHT it was 8.06 mg/mL. In the incubation assay, the BCS extract inhibited the formation of oxidation primary products in raw soybean oil at a concentration of 100 mg/mL. To conclude, BCS oil had a high content of polyunsaturated fatty acids and in spite of its high degree of unsaturation, the presence of phenolic compounds in BCS oil led to an increase in its relative oxidative stability. Also, at higher concentrations, BCS extract can compete with BHT in terms of antioxidant effects, and thus can be added into edible oils.
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W/O/W emulsions were easily prepared by oleogelation of the oil phase using rice bran wax (RBX) and their microstructure, stability, rheology and protection of proanthocyanidins and β-carotene were investigated. Formation of the W/O/W emulsion was confirmed using confocal laser scanning microscopy and staining of the inner aqueous phase by tartrazine. The average particle size and viscosity of the emulsion increased as the RBX concentration increased. Moreover, RBX increased the stability of the emulsion and the emulsion was the most stable when the RBX concentration was 8.0% or 10.0%. On the other hand, the W/O/W emulsions were used to simultaneously encapsulate proanthocyanidins and β-carotene. Specifically, proanthocyanidins and β-carotene in RBX-containing emulsions were more stable and had higher bioaccessibility than in the emulsion without RBX. Besides, both their chemical stability and bioaccessibility reached the maximum value when the RBX concentration was 8.0% or 10.0%. In summary, the optimal RBX concentration was 8.0%.
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In order to achieve a defined product behavior, the coating of particulate solids is an often used process in the food, chemical, and pharmaceutical industries. The wetting behavior affects the coating quality associated with hot-melt coating (HMC) considerably more than the quality associated with solvent-based coating. Thus, the uniformity and the effectiveness of the coating can be severely affected by process parameters. Furthermore, previous studies showed that delamination of the coating layer occurs frequently in HMC products [Mueller et al. 2018 (https://doi.org/10.1016/j.apt.2017.12.020); Woerthmann et al. 2021 (https://doi.org/10.1016/j.powtec.2020.09.065)]. Therefore, the successful use of natural coating materials requires a detailed understanding of the delamination and wetting behavior. The delamination observed for HMC-particles has, however, rarely been investigated, and the basis for and factors affecting this process remain unclear. However, a correlation between delamination and the wetting properties of the materials seems likely, since wetting properties provide information about the interaction between the coating and carrier material. In this work, the delamination frequency was investigated via laboratory coating experiments and via micro-computed tomographic measurements with different material combinations. In addition, the wetting behavior was investigated using a drop shape analyzer. No correlation between delamination and wetting behavior was found. All investigated coating agents exhibited excellent wetting properties with contact angles in a range of 10° to 18°, while palm fat coatings were more prone to delamination (>65%) than the rice bran (<10%) and carnauba wax coatings (<17%).
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Natural peanut butter was stabilized with 1.0%-2.0% (w/w) beeswax (BW), candelilla wax (CLW), rice bran wax (RBW), or sunflower wax (SFW). The appearance, spreadability, mouthfeel, and flavor attributes of these samples were evaluated by a trained sensory panel using commercial stabilized peanut butter and a sample stabilized with hydrogenated cottonseed oil as references. The waxes and their blend ratio significantly (p < 0.05) influenced appearance, spreadability, firmness, mouthfeel, and flavor attributes. Samples with 1.5%-2.0% CLW, or 1.0%-1.5% RBW had the fewest differences in appearance and texture from the reference and commercial samples. However, an off-flavor was attributed to 1.5% or higher CLW. Samples stabilized with BW or with 1.0%-1.5% RBW had the fewest difference in flavor compared to the reference sample. Overall, samples stabilized with 1.0%-1.5% RBW scored closest to the commercial and reference samples. The response of CLW, RBW, and SFW (which was only evaluated for appearance and spreadability) indicates that amounts of these waxes could be tailored in different products to achieve a product with desirable texture and flavor as well as stability to oil loss. PRACTICAL APPLICATION: This research provides information that could be used by food companies that make seed or nut butters as spreads or as ingredients for use in foods. It shows the impact of the use of four types of waxes as stabilizers, at commercially relevant levels (< 3.0%), and at levels previously shown to be effective for stabilization, on the firmness, spreadability, and other texture and flavor attributes, and thus provides a starting point for optimization for commercial product specifications.
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Cetyl palmitate is a wax ester naturally found in sperm whale spermaceti, and it is very much requested in the cosmetics industry. International regulations prohibit the sale of sperm whale spermaceti, so it is now being replaced by pure cetyl palmitate obtained by a chemical route or from mixtures based on jojoba oil. Another alternative is to use an enzymatic route for wax ester synthesis. For such a purpose, a new heterogeneous biocatalyst was prepared in our research group via physical adsorption of Burkholderia cepacia lipase on aerogel modified with a protic ionic liquid (IB‐IL‐OPT). Its catalytic activity was compared with the biocatalyst prepared using a non‐chemically modified silica aerogel (IB‐Control). The objective of this work is to apply this homemade heterogeneous biocatalyst to cetyl palmitate synthesis via a direct esterification reaction in a solvent system and to test the final product as a stabilizing agent in water/oil emulsions. IB‐IL‐OPT achieved maximum acid conversion of 95‐100% under optimal experimental conditions established by a Central Composite Rotational Design (CCRD): biocatalyst concentration of 14.8 % w.w‐1, molar ratio of 1:1.3, 41 °C for 15 h of reaction under continuous mechanical agitation (200 rpm). The IB‐Control gave 58.8% acid conversion in similar conditions. IB‐IL‐OPT was successively reused until 4 cycles. The wax ester showed potential as a good emulsifier for virgin coconut oil. The use of cetyl palmitate obtained by an enzymatic route without further purification showed good emulsifying potential, forming Pickering emulsions. This opens new perspectives for study and applications in the cosmetics industry. This article is protected by copyright. All rights reserved.
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Oleogelation is emerging as one of the most exigent oil structuring technique. The main objective of this study was to formulate and characterize rice bran/sunflower wax‐based oleogels using eight refined food grade oils such as sunflower oil, mustard oil, soybean oil, sesame oil, groundnut oil, rice bran oil, palm oil, and coconut oil. Stability and properties of these oleogels with respect to oil unsaturation and wax composition were explored. Sunflower wax exhibited excellent gelation ability even at 1%–1.5% (w/v) concentration compared to rice bran wax (8%–10% w/v). As the oleogelator concentration increased, peak melting temperature also increased with increase in strength of oleogels as per rheological studies. X‐ray diffraction and morphological studies revealed that oleogel microstructure has major influence of wax composition only. Sunflower wax oleogels unveiled rapid crystal formation with maximum oil binding capacity of 99.46% in highly unsaturated sunflower oil with maximum polyunsaturated fatty acid content. Further, the applicability of this wax based oleogels as solid fat substitute in marketed butter products was also scrutinized. The lowest value of solid fat content (SFC) in oleogel was 0.20% at 25°C, resembling closely with the marketed butter products. With increase in oil unsaturation, oleogels displayed remarkable reduction in SFC. Depending upon prerequisite, oleogel properties can be modulated by tuning wax type and oil unsaturation. In conclusion, this wax‐based oleogel can be used as solid fat substitute in food products with extensive applications in other fields too.
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Crude wax extracted from rice bran oil (RBO) used to improve the oleogel properties and oxidative stability of RBO. The effect of crude rice bran wax (CrBW) on the formation characteristics and oxidative stability of oleogels discussed. The results showed that oleogels could be formed with 7.0 wt% CrBW at 20°C. As the concentration of CrBW increased from 7.0 wt% to 11.0 wt%, the hardness and solid fat content (SFC) of the oleogels increased significantly, and the oleogels primarily β' crystals. Moreover, oleogel crystals formed with 5 wt% and 7 wt% CrBW are flocculent; when the amount included is 9%, the oleogel crystals are transformed into long dendrites, and the density rises. After 90 days of storage at 20°C, the peroxide value of oleogels formed with 9.0 wt% CrBW slowly rose from 3.21 to 6.52 mmol/kg. Practical Applications: In this study, oleogels prepared by crude rice bran wax (CrBW) and rice bran oil (RBO) are an innovative structural lipid without trans fats. This paper provides useful information on the rich fats and nutrients in CrBW, which reduces the production cost and improves the industrial production capacity. This article is protected by copyright. All rights reserved
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Biological wax esters are important commercial products used in various industrial and medicinal fields. These valuable compounds can be synthesized via several chemical and enzymatic reactions which have some advantages and more disadvantages. In particular, many strong acid catalysts cause undesirable structural changes in unsaturated fatty acids molecules. In the present study easily accessible 1‐hexadecyl‐3‐sulfoimidazolium chloride as ionic liquid was screened as a mild Brønsted acid metal free catalyst for the chemical esterification or transesterification of equimolar amounts of long chain fatty acids or fatty acid methyl esters respectively with fatty alcohols in solventless medium. The various parameters affecting the yield of the wax ester were optimized, catalyst reuse studies and large scale synthesis were also carried out. According to this alternative practical and green process, a series of wax esters (17 examples) were produced readily in good to excellent yields. There was no undesirable geometric cis‐trans isomerization in unsaturated fatty acids under the reaction conditions used. The catalyst is also quite effective when triglycerides are converted directly to the wax esters via transesterification reaction. In the present study, we present effective and green methods for the preparation and characterization a series of wax esters. Practical applications: With effortlessly and environmentally friendly method developed in this study, various wax esters can be synthesized as valuable industrial materials. In order to synthesis these esters, there is no any restriction for starting compounds. The most important aspect of the developed procedures is that metallic or strong aggressive acidic catalysts are not used compared to existing procedures. It is possible to carry out large‐scale syntheses of esters with high yields.
Chapter
Rice bran oil (RBO) is named as wonder oil or “heart oil” in many Asian countries and is considered an imminent functional food ingredient in western countries. High amounts of unsaturated fatty acids namely oleic and linoleic, 3–4% wax, 0.8% glycolipids, 1–2% phospholipids, and bioactive compounds such as γ-oryzanol (1.2–1.7%), phytosterols, tocopherols (0.02–0.08%), and tocotrienols (0.025–0.17%) are present in crude RBO. These bioactive compounds in RBO demonstrate antioxidative, antidermatitic, antidiabetic, chemopreventive, and cholesterol-lowering properties which makes it an ideal oil to be used in pharmaceutical, chemical, and food industries. In food industries owing to its palatability, plasticity, and spreadability it finds application in margarine and shortenings manufacturing and can also be incorporated in products like bread, cakes, noodles, pasta, and ice creams to increase their nutritive value without affecting textural and functional properties.
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It document is constitutive of the article entitled "Technological routes of Policosanol extraction: a systematic literature review and patent prospection" by Rilton Gonçalo Bonfim Primo, Jesus Martín-Gil, Fernando Cardoso Pedrão, Carlos Narciso Bouza and Ricardo de Araújo Kalid. This work was conducted during a scholarship supported by the Institutional Sandwich Doctorate Program Abroad (PDSE) at the Federal University of Bahia (UFBA), Salvador, Brazil, and University of Valladolid (UVA), Palencia, Spanish. Revised, edited and published by the Centro de Estudios por la Amistad de Latinoamérica Asia y África - Ceala (www.ceala.org). Financed by CAPES – Brazilian Federal Agency for Support and Evaluation of Graduate Education within the Ministry of Education of Brazil - Finance Code 001.
Preprint
It document is constitutive of the article entitled "Technological routes of Policosanol extraction: a systematic literature review and patent prospection" by Rilton Gonçalo Bonfim Primo, Jesus Martín-Gil, Fernando Cardoso Pedrão, Carlos Narciso Bouza and Ricardo de Araújo Kalid. This work was conducted during a scholarship supported by the Institutional Sandwich Doctorate Program Abroad (PDSE) at the Federal University of Bahia. Financed by CAPES – Brazilian Federal Agency for Support and Evaluation of Graduate Education within the Ministry of Education of Brazil - Finance Code 001.
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Aerogels require nontoxic coatings which are good barriers to the environment and do not affect the fragile porous network. There is a wide range of coating materials available for a variety of applications and functionalities. Waxes, for example, are good moisture barrier candidates and do not require additional solvents during processing. Hence, in this work four different natural waxes were tested concerning their application as coating material for porous aerogels. Therefore, beeswax, candelilla wax, rice bran wax and sunflower wax were investigated regarding their thermic properties, moisture barrier properties and wettability. Beeswax and rice wax proved favourable for coating aerogels. Beeswax shows low water vapour permeability, low minimum film forming temperature and forms continuous films. The water vapour permeability of rice wax is higher compared to beeswax, but there is no minimum film forming temperature in the temperature range of 20 °C–80 °C and the appearance of the rice wax films is homogeneous. Candelilla wax and sunflower wax are not suitable for coating of aerogels. Candelilla wax forms discontinuous films which diminish its water barrier properties. Sunflower wax has the highest water vapour permeability, forms porous films and forms cracks on the surface of the film during solidification below 62 °C.
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Nyamplung ( Calophyllum inophyllum ) is a multi-functional plant which is spread widely over the coast of Indonesia. Its seed produces a high content of oil, but its utilization is still limited. It is because C.inophyllum seed oil contains toxic compounds. Therefore, C.inophyllum seed oil has been used as a biodiesel raw material for many years. It was reported that C.inophyllum seed oil contains wax, but its percentage remains unknown. Wax has been used in cosmetics, pharmaceuticals, foods, and coatings industries as oil binder, water repellent, scratch resistance, and dispersion medium. In this work, wax was separated from C.inophyllum seed oil by solvent crystallization with and without separating non-polar lipid fraction (NPLF) from crude oil. Non-polar lipid fraction was separated by batch-wise solvent extraction using petroleum ether to methanol mass ratio of 3:1 (w/w) for eight stages. After eight stages, non-polar lipid fraction was collected for further separation by solvent crystallization method. The ratios of non-polar lipid fraction to acetone were 1:10, 1:20, and 1:40 (w/v). Then, the isolated wax was analyzed by gas chromatography. It was found that wax (purity of 40% and yield of 0.35%) was successfully isolated by separating non-polar lipid fraction from crude oil (batch wise solvent extraction for eight stages) and followed by solvent crystallization (non-polar lipid fraction to acetone ratio of 1:40 (w/v)).
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Purpose of Review Overwhelming evidence indicates that reduction of blood low-density lipoprotein cholesterol (LDL-C), ratio of LDL-C/HDL-C, and TG/HDL-C ameliorate the occurrence of atherosclerotic cardiovascular disease. Long-chain alcohols and aldehydes known generically as policosanol (PC) and policosanal have attracted attention from researchers and scientists due to their cholesterol-lowering health benefits. Many researchers reported that PC decreased serum cholesterol, while others failed to reproduce this effect. The objective of this investigation was to update research data and establish the optimal future research direction of PC as a cholesterol-lowering alternative for use in food, dietary supplements, and pharmaceutical industries. Recent Findings PC distribution differs in individual plants and maturity stage affects composition. PCs are considered as limiting nutraceuticals. Regular food sources for humans include rice bran oil, olive oil especially cold-pressed extraction, and non-centrifugal sugar products from sugarcane. Waste products discarded from rice bran oil are considered as good sources of policosanol. Most human clinical trials found PC to be effective in reducing serum cholesterol, whereas others reported no effect, especially for PC extracted from dietary sources. Inhibition of HMG-CoA reductase as the rate-controlling enzyme of the mevalonate pathway has been proved as the cellular mechanism which lowers serum-cholesterol levels. This review offers ideas for the direction of future PC research. Summary PC is a limited nutraceutical which offers promise for the prevention of hypercholesterolemia. Further studies are required to determine an effective PC composition for cholesterol reduction which will benefit the food, dietary supplement, and pharmaceutical industries.
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Natural waxes are cost-effective and potential fat crystallization modifier, whereas there are limited information about their implementation on solid triacylglycerols (TAGs) oil. Herein, we investigated the effects of two natural waxes with different concentrations (2, 4, 6, 8 wt%) and carbon chains on the crystal growth and structure of palm kernel stearin (PKS85). Candelilla wax (CLW) could significantly accelerate PKS85 crystallization process. Both two waxes could induce a new hydrocarbon chain with the distances of 3.70 and 4.15Å during TAGs crystallization. More particularly, X-ray diffraction (XRD) indicated that PKS85 combined with CLW showed similar lamellar thickness (d001) and crystal domain size () with pure PKS85, whereas PKS85 containing rice bran wax (RW) were 1.7-1.8 and 1.5-1.8 folds for d001 and , respectively. This corresponded to the carbon chain length of CLW and RW, which were double and quadruple PKS85. Further, these variations were reflected on the crystal microstructures of PKS85 with CLW or RW: the former showed small homogeneous crystals, while the latter displayed large rod-like layer crystals. Additionally, the firmness significantly increased when adding CLW and RW, which possibly attributed to the fact that the waxes become the backbone of the crystal “fence”. Our findings give a clear insight into the interaction between TAGs and waxes molecules in the crystallization, which could guide natural waxes utilization in the fat modification.
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Improved knowledge of the properties, composition, and analysis of grain sorghum wax would assist in efforts for industrial application of this product. Wax extracted from grain sorghum, harvested in 1996 in Nebraska, using hot hexane was fractionated with silica gel column chromatography using a series of mixtures of hexane, chloroform, methanol, and acttic acid. During TLC analysis of the sorghum wax, a dark band, which did not appear in carnauba wax, was found between was esters and TAG. This dark band fraction was the primary component, representing more than 40% of the total sorghum wax weight. The purpose of this study was to chemically characterize the dark band. The fraction containing the dark band was subjected to borohydride reduction and autoxidation by exposure to air. The borohydride reduction gave a dark band at the fatty alcohol position on TLC, whereas the oxidized sample showed a dark band at the FA position, strongly suggesting the original dark band contained aldehydes. NMR and GC-MS data confirmed that this fraction contained a saturated C28 aldehyde.
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A chromatographic method is described to measure the crystallizable wax content of crude and refined sunflower oil. It can also be applied to any other vegetable oil. The preparative liquid chromatography step on a glass column containing a silica gel adsorbent superimposed upon a silver nitrate-impregnated silica gel support is used to isolate a wax fraction which is then analyzed by gas chromatography. The recovered wax fraction contains, in addition to the crystallizable waxes, hydrocarbons and other compounds with gas chromatographic retention times corresponding to waxes with chain lengths C34−C42. These compounds are short-chain saturated waxes in fruit oils, such as grapeseed and pomace. In seed oils such as sunflower, soybean or peanut, the compounds initially referred to as “soluble esters” are identified as monounsaturated waxes, esters of long-chain saturated fatty acids, and a monounsaturated alcohol, mainly eicosenoic alcohol. Such waxes are absent from corn or rice bran oils.
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Four classes of wax lipids (sterylester, longer alkylester, shorter alkylester and hydrocarbon) were isolated from rice bran, and their chemical characteristics and constituents investigated. The main component fatty acids were linoleic, oleic and palmitic acid for sterylester; behenic, lignoceric and palmitic acid for longer alkylester; and oleic and palmitic acid for shorter alkylester. The representative molecular species were sitosteryl linoleate (linoleoyl sitosterol) and sitosteryl oleate (oleoyl sitosterol) for sterylester; dotriacontanyl behenate (behenoyl dotriacontanol), octacosanyl palmitate (palmitoyl octacosanol) and tetratriacontanyl behenate (behenoyl tetratriacontanol) for longer alkylester; and methyl oleate, methyl palmitate and ethyl oleate for shorter alkylester. Straight-chain alkane and alkene, and branched-chain alkene (squalene) were detected as hydrocarbons. The principal carbon number of alkane was C29 and C31 and that of alkene, C29, C31 and C33. © 1981, Japan Society for Bioscience, Biotechnology, and Agrochemistry. All rights reserved.
Article
The reduction of cobalt(II) with borohydride is very complicated, as evidenced by the fact that various authors have obtained different reaction stoichiometries and have proposed a number of mechanisms. To clarify the cobalt reduction process, the reaction stoichiometry and reduction efficiency were studied using a controlled rate of addition of sodium borohydride in the temperature range 5–35°C and at pH values from 2 to 7.8.The efficiency of cobalt reduction increased with increasing concentration of NaOH in the reducing solution, the best reduction efficiency without the precipitation of cobalt hydroxide being 1 mole of sodium borohydride to reduce 1 mole of cobalt(II). The reduction efficiency increased with increasing pH, from nil at pH 2 to 96% at pH 6, and decreased with increasing temperature.X-ray diffraction patterns and TEM patterns of the recovered precipitates showed them to be amorphous. After a 2 h heat treatment at 500°C, the X-ray diffraction pattern of the precipitate showed well defined peaks due to Co2B, with the main peak attributable to cobalt. The single crystal TEM pattern obtained was consistent with that of Co2B. The particle size was about 20–100 nm. The atom ratio of Co to B increased with increasing temperature.Zinc ions have a dramatic inhibitory effect on cobalt reduction. Several tens of micromoles per litre of zinc ions completely inhibit cobalt reduction with borohydride. The main cause of inhibition is that zinc ions compete with those of cobalt for borohydride ions and zinc borohydride forms and hydrolyzes rapidly.
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High-field (600 MHz) nuclear magnetic resonance (NMR) spectroscopy was applied to the direct analysis of virgin olive oil. Minor components were studied to assess oil quality and genuineness. Unsaturated and saturated aldehyde resonances, as well as those related to other volatile compounds, were identified in the low-field region of the spectrum by two-dimensional techniques. Unsaturated aldehydes can be related to the sensory quality of oils. Other unidentified peaks are due to volatile components, because they disappear after nitrogen fluxing. The statistical analysis performed on the intensity of these peaks in several oil samples, obtained from different olive varieties, allows clustering and identification of oils arising from the same olive variety. Diacylglycerols, linolenic acid, other volatile components, water, acetic acid, phenols, and sterols can be detected simulteneously, suggesting a useful application of high-field NMR in the authentication and quality assessment of virgin olive oil.
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Qualitative and quantitative aspects of proteins, carbohydrates, lipids, vitamins, minerals, and antinutritional factors in rice bran and its subfractions are described. The nutritional value measured in animal feeding tests is summarized for bran, defatted bran, stabilized bran, and protein concentrates derived by alkaline extraction of bran. Stabilization of rice bran and how this process may lead to a quantum change in its utilization in foods and for recovery of edible oil is discussed. Present uses of rice bran in foodstuffs are described.
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The discoloration of paper on aging is of interest to the archival community and also to the pulp and paper industry where new and improved mechanical pulps are being developed. The yellowing of paper on aging can be attributed to the presence of chromophores found in some of the products formed from the degradation of one or more components of paper. This study identifies the nature of the chromophores found in cellulose, hemicellulose and lignin. The photooxidation of lignin-containing papers and the mechanism for photoyellowing are discussed. This is followed by a description of the basic principles of conservation bleaching which involves chemically treating papers in order to remove unwanted discoloration or stains. The washing of paper and the use of oxidizing and reducing bleaches are presented. The discussion on oxidizing bleaches includes hydrogen peroxide, alkaline hypochlorite, chlorine dioxide and sunlight. The chemistry of reducing bleaches focuses on dithionites and borohydrides. Keywords (Audience): Upper-Division Undergraduate
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Hard and soft waxes were separated from the tank settling of crude rice bran oil by solvent extraction and analyzed for their composition by gas liquid chromatography (GLC). The results showed that the melting points of the hard wax and the soft wax were 79.5 C and 74 C, respectively, and that the hard wax was mainly composed of saturated fatty alcohols of C24, C26 and C30, saturated fatty acids of C22, C24 and C26, andn-alkanes of C29 and C31. The soft wax was mainly composed of saturated fatty alcohols of C24 and C30, saturated fatty acids of C16 and C26, andn-alkanes of C21 and C29. In the soft wax, lauric acid was also detected.
Article
A wax-like settling is observed in tanks in which rice bran oil is stored. “Soft” and “hard” wax fractions have been isolated from this settling by solvent Crystallization. Previous investigation has shown that the settling consists mainly of wax esters of long chain alcohols and long chain fatty acids. The present work describes the column chromatographic analysis of unhydrolyzed tank settling. The presence of an aromatic moiety is indicated in the infra red spectrum. Comparison of data obtained by analysis of the tank settling before and after hydrolysis shows that it contains only 33% of monomeric esters; the remainder may be present as a polymeric ester, as found in carnauba wax. Investigation of different samples of rice bran oil has shown that the ratio of monomeric to polymeric fraction varies with the history of the bran.
Article
PUFA, such as arachidonic acid (AA), have several pharmaceutical applications. An efficient method was developed to obtain high-purity arachidonic acid (AA) from ARASCO, a single-cell oil from Martek (Columbia, MD). The method comprises three steps. In the first step, AA was enriched from saponified ARASCO oil by low-temperature solvent crystallization using a polar, aprotic solvent, which gave a FA fraction containing 75.7% AA with 97.3% yield. The second step involved enriching AA content via lipase-catalyzed selective esterification of FA with lauryl alcohol. When a mixture of 1 g FA/lauryl alcohol (2∶1 mol/mol), 50 mg Candida rugosa lipase, and 0.33 g water was incubated at 50°C for 24 h with stirring at 400 rpm, the AA content in the unesterified FA fraction was as much as 89.3%, with ca. 90% yield. Finally, a solvent extraction procedure, in which acetonitrile was the extracting solvent, was used to enrich AA from FA fraction dissolved in n-hexane. The best results were obtained when 2 g FA was dissolved in 80 mL hexane and extracted twice, each time with 20 mL acetonitrile at −20°C, by allowing 2 h storage. This step gave a FA fraction containing 95.3% AA with 81.2% yield. By using this three-step process the AA content in the saponified single-cell oil (ARASCO) was increased from 38.8 to 95.3% with a total yield of ca. 71%.
Bleaching Rice Bran Wax
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Bennett, H., Carnauba Wax, in Industrial Waxes, Chemical Pub-lishing, New York, 1974, Vol. 1, pp. 169–172.
Studies on the PREPARATION OF FOOD-GRADE RICE BRAN WAX Rice Bran and Rice Bran Oil. XIII. Bleaching Rice Bran Wax
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Rao, B.P., G.S.R. Reddy, and S.D. Thirumala, Studies on the PREPARATION OF FOOD-GRADE RICE BRAN WAX Rice Bran and Rice Bran Oil. XIII. Bleaching Rice Bran Wax, J. Oil Technol. Assoc. India (Mumbai, India) 2:32–33 (1970).
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Composition and Potential Food Sources
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  • Rice Bran
Characterization of Natural Waxes and Their Application to Cosmetic Foundations
  • Ito
Rice Bran Wax, a New Wax for Cosmetics, Drugs, and Toiletries
  • Buffa
Anticholesteremic and Triglyceride-Lowering Effects of Compositions Containing Phytosterol and Policosanol Esters of Fatty Acids
  • E M Schersl
Natural Mixture Composed of Higher Primary Aliphatic Alcohols Obtained from Bee Wax for the Treatment of Gastric and Duodenal Ulcers That Also Present Anti-inflammatory Activity
  • J M Hernandez
  • A L Granja
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  • D C Quintana
  • V M Sanchez
  • S V Garcia
  • M D Gomez
Simultaneous Degumming and Bleaching of Rice Bran Waxes
  • Y T Yamagata
  • Nishigori
Purification of Wax from Rice Bran
  • K Nakagawa
Studies on the Rice Bran and Rice Bran Oil. XIII. Bleaching Rice Bran Wax
  • Rao
Study on Refining of Rice Bran Wax
  • Wang
Natural Mixture Composed of Higher Primary Aliphatic Alcohols Obtained from Bee Wax for the Treatment of Gastric and Duodenal Ulcers That Also Present Anti
  • J M A L Hernandez
  • R M Granja
  • M L A Ferreiro
  • D C Valmana
  • V M Quintana
  • S V Sanchez
  • M D Garcia
  • Gomez