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Cocoa butter alternative fats
Abstract
Cocoa butter is a natural and highly valued fat that contributes to the desirable textural and sensory properties of chocolate and confectionery products. Thanks to its unique triglyceride composition cocoa butter is responsible for the most important qualities of produced chocolate, namely gloss, brittleness, hardness, and rapid and complete melting in the mouth. The rise in the price of cocoa butter forced confectioners to seek of cheaper and more readily available alternative fats derived from various natural sources. Alternative fats can be divided into three main group by their application, namely cocoa butter replacers, cocoa butter equivalents and cocoa butter substitutes. The cocoa butter alternatives can be produced by blending and/or modifying vegetable fats. The main processes used in the industry to modify physico-chemical characteristics of oils and fats are fractionation, interesterification and hydrogenation.
Cocoa butter equivalents (CBE) are usually
produced using exotic butters or tropical fats from illipe,
palm mid-fraction, sal, shea, kokum, and mango kernel.
These exotic butters are often harvested from the wild trees,
their supply is limited, and their quality can be varied. In
this study, we report on the physicochemical and functional
properties of two new CBE made from algal butter, and
compared them to those of a commercial shea stearin
(cSS). The functionality of these fats as CBE in a model
chocolate system was assessed and compared to a cocoa
butter (CB) control. The fatty-acid composition and the
triacylglycerol profile of algal butters were similar to cSS.
The crystallization temperature, melting point, and crystal
polymorphic form (β2 3-L) of the algal butters were similar
to those of cSS. No significant differences (P <0.05) in
hardness and bloom formation were observed. One-year
storage at room temperature caused bloom formation in all
chocolates, as evidenced from a βV to βVI polymorphic
transformation, except for 100% algal butters and cSS.
According to the results of this study, algal butter is compatible
with CB and can be used as a novel CBE in chocolate
products.
Chocolate samples (22 in total, including 11 samples of milk chocolate) were bought from retail store in Prague and tested for their CBEs contents in relation to the declaration of CBE addition on the product labels. The modified method of Padley and Timms was employed for determining selected triglycerides (C50, C52 and C54). The presence of CBEs in chocolate was evaluated using the following relationship: %C50 < 44.095 - (0.737 x %C54). The content of CBE in chocolate was determined using the method of Young, modified by the replacement of the original graphical procedure with the numerical processing of the results. 19 samples i.e. 90% of the total, satisfied the requirements of Directive 2000/36/EC. In view that no official methods for CBE detection and quantification in chocolate have been published up to now and older methods were used in this work, the results published here should be considered as indicative and satisfying the requirements for screening only.
The seeds and seed oil of Terminalia catappa were analyzed to establish their chemical compositions and nutritional properties in order to investigate the possibility of using them for human and/or animal consumption. The seed is a good source of oil and protein; these were found to be 51.80% and 23.78% respectively. The seeds were found to be good sources of minerals. Potassium (9280 ± 0.14 mg/100g) was the highest, followed in descending order by Calcium (827.20 ± 2.18 mg/100g), Magnesium (798.6 ± 0.32 mg/100g) and Sodium (27.89 ± 0.42 mg/100g).The physical properties of the oil extracts showed the state to be liquid at room temperature. The saponification value suggest the use of this oil in liquid soap, shampoo and oil based ice cream production. The moisture content is also low (4.13%) which indicates the possibility of long shelve-life. The degradation kinetic of the oil was also investigated. The thermal oxidation of the double bonds of the oil showed a first-order thermal oxidation kinetic and the Arrhenius plot yielded a straight line with a slope equivalent to activation energy of 7.752 KJ.mol-1. There is the possibility of considering the seed as feed supplement and its oil for industrial application.
The proximate composition, mineral concentration of fleshy mesocarp, palm meat (PM) and palm kernel (PK) of oil palm fruit (Elaeis guineensis S.L.Dura) produced in Hainan, China were investigated. The fatty acid composition, chemical properties and minor constituents of palm oil (PO) and palm kernel oil (PKO) were also studied. The crude fat of PM and PK were 68.09±3.57% and 49.36±2.61%, respectively. The PM and PK were found to be good sources of minerals. The acid value (AV) and free fatty acid (FFA) of PO extracted from fresh PM were much higher. If the fresh PM were heated at 100ºC for 30 min, the AV and % FFA could be reduced to 4.62±0.04 mgKOH/g and 2.72±0.002%, respectively. The major fatty acid of PO was palmitic acid 39.93±1.66% and that of PKO was lauric acid 48.01±0.69%. Tocopherol isomer (α-, (β+γ)-and δ-) contents in PO were 68.8±1.84, 22.8±0.54 and 11.8±0.12 mg/kg, respectively. The β-carotene content in PO was 901.5±11.95 mg/kg. The content of sterols in PO and PKO were 880.0±5.23 and 858.0±4.37 mg/kg, respectively. PO and PKO exhibited good chemical properties and could be used as edible oils and for industrial applications. There are almost no data about Chinese palm fruit now and this study systematically researched on it, which can provide useful information for Chinese oil palm industry.
Chocolate is acclaimed for its unique and highly desirable flavor and its unusual melting characteristics (a narrow melting point range centered a few degrees below body temperature ∼32 to ∼35 °C). The triacylglycerol (TAG) composition of cocoa butter is responsible for this important melting behavior. The exact composition of the primary TAG in a Malaysian cocoa butter sample was elucidated by ESI/tandem mass spectroscopy. The cocoa butter sample consisted primarily of the TAG, POP, POS and SOS with smaller amounts of PLP, POO, PLS, and SOO, where P, O, S, and L indicated palmitic, oleic, stearic and linoleic acid, respectively. The use of tandem mass spectroscopy or MS/MS was critical for the identification of coeluted TAG, such as POO and PLS. The fragmentation pattern provided by diacylglycerol sodium adduct ions, enabled the identification of co-eluted TAG by the loss of a fatty acid fragment and the corresponding diacylglycerol sodium adduct ion.
The current concern for cocoa butter fat as major ingredients of chocolate intake in the World has raised the question of the high price of cocoa butter among all other vegetable fats. Productions of natural cocoa butter fats are decreasing day by day due to the decrease of cocoa cultivation worldwide; moreover, cocoa fruit contains only a little amount of cocoa butter. Therefore, the food industries are keen to find the alternatives to cocoa butter fat and this issue has been contemplated among food manufacturers. This review offers an update of scientific research conducted in relation to the alternative fats of cocoa butter from natural sources. The findings highlights how these cocoa butter alternatives are being produced either by blending, modifying the natural oils or fats from palm oil, palm kernel oil, mango seed kernel fats, kokum butter fat, sal fat, shea butter, and illipé fat.
Fat is the most expensive component in confectionery such as chocolate. It may comprise of cocoa butter, milk fat, palm oil, lauric oil, exotic fats, etc. This new handbook, with a large number of figures and tables, provides a comprehensive guide to all aspects of confectionery fats, with particular emphasis on the later. Unlike sugar confectionery, chocolate is a fat-continuous product and the sugar, like the other non-fat components, is merely mixed with the fat rather than melted/boiled. The properties of chocolate confectionery are thus determined mainly by the fat, which comprises about 26-35% in a typical chocolate formulation. The book describes the essential physical chemistry needed to understand the properties of confectionery fats, analytical methods, raw materials, the production and properties of confectionery fats, and their application in sugar and chocolate confectionery. It concludes with consideration of legislation and regulatory aspects of producing confectionery and of using milk fat, cocoa butter and alternative fats together with a chapter on analytical methods for detecting and quantifying confectionery fats. Finally, four appendixes provide: a glossary of terms and abbreviations used; details of confectionery fat manufacturers; details of confectionary fat products produced by these manufacturers; and a list of websites from other relevant organizations that the reader may find useful. © PJ Barnes & Associates, 2003;
Cocoa butter equivalent could be synthesized by lipase-catalyzed interesterification of oil. The objective of this research was to investigate the synthesis of cocoa butter equivalent from interesterification of palm oil catalyzed by Carica papaya lipase. The study showed that the compositions of cocoa butter equivalent were affected by acyl donor sources, substrate ratio, initial water of enzyme, reaction time, reaction temperature and the amount of enzyme. Among three acyl donors tested (methyl stearate, ethyl stearate and stearic acid), methyl stearate appeared to be the best acyl donor for the synthesis of cocoa butter equivalent from palm oil catalyzed by C. papaya lipase. The best reaction conditions were: substrate ratio (palm oil: methyl stearate, mol/mol) at 1: 4, water activity of enzyme at 0.11, reaction time at 4 h, reaction temperature at 45oC and 18% by weight of the enzyme. The chemical and physical properties of cocoa butter equivalent were 9.75 ± 0.41% free fatty acid, 44.89 ± 0.84 iodine number, 193.19 ± 0.78 sponification value and melting point at 37-39oC. The yield of cocoa butter equivalent was 55% based on palm oil used.
Kokum kernel is a byproduct of agro-processing industry in India containing about 40–50% fat which has the potential as a worthy cocoa butter alternative (CBA). However, inefficient extraction techniques that are practiced at cottage level restrict its industrial applications. This work reports on the optimization of the technique of three phase partitioning (TPP) for efficient extraction of kokum kernel fat. The parameters of TPP were optimized with respect to ammonium sulphate concentration, ratio of slurry to t-butanol and pH of slurry. The optimized protocol resulted in maximum recovery of 95% (w/w) fat recovery within 2 h. The technique is economical and eco-friendly, and is promising for utilization of agro-processing waste in India to a product of commercial significance.
Some physical properties of shea kernels were determined in order to design equipment and facilities to process ‘shea butter’, an important vegetable fat made from shea kernels. At a moisture content of 4·35% d.b., the average length, width and thickness of shea kernel were 31·50, 23·70 and 22·00 mm, respectively. The average geometric mean diameter sphericity and density were 2·52 cm, 0·80 and 1·17 g/cm3, respectively, while the static coefficient of friction varied from 0·36 on plywood with grain parallel to direction of motion to 0·52 on galvanized steel. The angle of repose was 34°.
Heat transfers that occurred during chicken fat dry fractionation process were characterized. Thermal behaviour of chicken fat and the olein and stearin fractions obtained were determined. The heat flow model developed in this study led to follow the heat flow associated with crystallization (ϕr) during the cooling step. Stearin mass and crystal mass (calculated from stearin solid fat content measurements by nuclear magnetic resonance) were determined experimentally at 30, 170 and 300min cooling time. Their variation towards a plateau value after 170min of cooling was related with a decrease in heat flow associated with crystallization. The results reported suggested that monitoring ϕr during cooling could be useful for the prediction and control of crystallization kinetics and therefore stearin yield.
Cocoa butter equivalent (CBE) was prepared by interesterification of tea seed oil, methyl palmitate and methyl stearate with lipase. The lipase was immobilized on macroporous resin selected from eight carriers. The rate of reaction of lipase immobilized on macroporous resin was 6.9 times higher than that of the free enzyme. After repeating application five times, 83.50% activity, of the immobilized lipase, was retained. Factors such as reaction time, temperature, water content, enzyme load and substrate ratio were studied. Three major acyls (palmitoyl, oleoyl and stearoyl) in triacylglycerols of the product were similar to those of cocoa butter. The melting range and dilatation–temperature curves of the prepared CBE were close to that of the cocoa butter.
Authenticity is an important issue for the food industry due to legal compliance, economic reasons (right goods for the right price), guarantee of a constant well-defined quality, use of safe ingredients (no hazardous substitutes), and religious reasons (halal, kosher). This report gives an extensive overview on the authenticity assessment of oils and fats for food products and summarizes the principal techniques useful for this assessment. Scope and limits of different analytical tools are discussed.
Nutritive information about oil palm kernel is scarce, especially on the composition of sugars and water-soluble vitamins. This study aims to evaluate both tenera and clonal materials for their proximate composition, fatty acid profile, amino acid composition, sugar, mineral and water-soluble vitamin contents. The tenera material had a higher moisture, fat and fibre content as compared to the clonal material, whereas protein, carbohydrate and ash content were higher in the clonal material. The major fatty acid constituents in palm kernel oil were lauric acid, myristic acid and oleic acid. The palm kernel proteins were deficient in lysine and tryptophan but rich in glutamic acid, arginine and aspartic acid. Sucrose was the most abundant sugar in palm kernel. The mineral analysis of the samples showed high levels of potassium, phosphorus, magnesium, calcium and manganese, while niacin was the water-soluble vitamin present at the highest concentrations in palm kernel.Highlights► Chemical composition of tenera and clonal palm kernels are very similar. ► Palm kernels are rich in disaccharides, acidic amino acid, and saturated fatty acids. ► Palm kernels are good source of potassium. ► Niacin is the dominant water-soluble vitamin in palm kernels. ► Biological replicates reveal clonal material is more uniform than tenera.
There is a likelihood of food shortage becoming acute in developing countries and people will have to depend increasingly on plants rather than animals for their dietary requirements. To meet the growing demand of fat which have texture like butter because of the higher percentage of saturated fatty acids, little known or neglected plants could be investigated. The paper reviews the work so far done on such aspect and highlights the plants which could be taken up for systematic plantation.Butter aus PflanzenEs ist wahrscheinlich, daß eine Lebensmittelknappheit in den Entwicklungsländern akut wird und die Menschen in zunehmendem Maße bei ihren Nahrungserfordernissen mehr von Pflanzen als von Tieren abhängig sein werden. Um die wachsende Nachfrage nach Fett mit butterähnlicher Struktur wegen des höheren Prozentsatzes an gesättigten Fettsäuren zu erfüllen, könnten wenig bekannte oder vernachlässigte Pflanzen untersucht werden. Der Bericht gibt einen Überblick über die bis jetzt zu diesem Thema gemachten Arbeiten und stellt die Pflanzen heraus, welche für eine systematische Pflanzung herausgegriffen werden könnten.
In this study, the crystallization and melting properties of four different fat blends with the same saturated fat content (30%) but with different ratios of symmetric and asymmetric monounsaturated triacylglycerols were investigated using pNMR, DSC and polarized light microscopy. Blends were either palmitic (P) or stearic (S) based, and were combinations of SatOSat-rich (Sat = saturated, O = oleic) and SatSatO-rich vegetable oils with high-oleic sunflower oil. The DSC results demonstrate that there was almost no difference in crystallization mechanism and crystallization rate between the two P-based blends. Both blends showed a two-step crystallization, which can be explained by polymorphism. Stop-and-return DSC results suggested an initial crystallization into an unstable polymorph followed by polymorphic transition during the crystallization. For the S-based blends there was a clear difference between the SOS-rich and the SSO-rich blend, with a slower crystallization for the SSO-rich blend. Possibly, this can be explained by fractional crystallization. The microstructure did not differ greatly between the blends. Directly after crystallization, the crystals of the SSO-rich blend were slightly larger than the crystals of the SOS-rich blend.
Modification techniques like fractionation, interesterification (chemical or enzymatic) and hydrogenation allow proposing a large range of new fatty products. At a time when “trans” fatty acids are questioned, fractionation of fats and oils catches more and more interest; in this context, dry fractionation is by far the simplest and cheapest fractional crystallization technique (no chemicals, no effluent and no losses). The oil processing industry uses dry fractionation to extend the application of a whole variety of fatty matters as well as to replace, fully or partially, the chemical modifications. Due to the continuous developments of the dry fractionation process, a whole variety of products normally produced by solvent fractionation can now be obtained with a high degree of selectivity with dry fractionation. As the crystallization operates in the bulk, viscosity problems limit the degree of crystallization in one single step, and multi-step operations are currently used, giving rise to a wide range of fractions suitable for different applications. The secret is to combine proper crystal development with highly efficient separation by using membrane press filters allowing squeezing out the stearin cake for as much liquid occlusion (olein) as possible. The original booming of the dry fractionation process has helped mostly palm oil to conquer a strong position on the commodity market in one single stage; today, palm oil is without doubt the most widely fractionated oil. New demands for special cuts drifted the industry towards a more sophisticated approach: high-iodine value super and top oleins, palm red fractions (high carotene and tocopherol/tocotrienol contents) or solvent-free cocoa butter equivalents (palm mid fractions) are certainly what the future has in store.
Palm oil provides significantly higher amounts of oil/ha than any other commercial oil crop. Palm oil can be physically refined and fractionated into various fractions, ranging from very hard palm stearin with iodine values below 10 to palm superolein with iodine values as high as 72. Palm mid fractions consisting of symmetrical triacylglycerols provide sharp-melting fats for niche applications. The wide range of palm oil fractions provides versatility for different food applications, with the additional advantage that natural palm oil is trans free and genetic modification free. Palm oil and its fractions are widely used for direct blending with other oils or are interesterified with other oils to meet the trans-free fat requirements of the food industry. The sn-2 position of palm oil triacylglycerols is mainly esterified with oleic and linoleic acid. This provides better bioavailability of oleic acid as monounsaturated fatty acid and linoleic acid as an essential fatty acid, as compared to oils or fats with similar composition but with randomized fatty acid distribution. Crude palm oil also contains highly valuable minor components, including carotenoids and tocotrienols, which are potent fat-soluble antioxidants. Recent research findings on potential chemo-preventive and chemotherapeutic roles of tocotrienols are extremely encouraging.
The production of a cocoa butter equivalent (CBE) through enzymic interesterification of palm oil midfraction (POMF) with stearic acid in a solvent free system using Novo lipase Lipozyme™ as a catalyst was analyzed. A two level factorial design was used to study the effect of the initial ratio of stearic acid–POMF, initial humidity of the enzyme preparation and the enzyme–substrate ratio on the yield, mass productivity and specific productivity. Studies were carried out both in batch and in a continuous packed bed reactor. The highest specific productivity obtained in shake flask was 0.0393 g/Batch Interesterification Unit (BIU) h at a stearic acid–POMF ratio of 1.6 and enzyme–substrate ratio of 23 BIU/g. In the continuous packed bed reactor the highest mass productivity observed was 1.54 g/g·h, using an enzymic load of 73 BIU/g. Unreacted fatty acids were separated from the intereresterified products by short path distillation at 0.2 mbar and 140°C obtaining a product practically without free fatty acids. Thermograms of the products obtained by scanning differential calorimetry were similar to cocoa butter (CB), but exhibited several distinct peaks, due presumably to the presence of diglycerides and trisaturated triglycerides.
Cocoa butter equivalents (CBEs) are fats with a similar composition and melting profile as cocoa butter (CB), which are usually prepared by blending mid-palm fractions and stearate-rich tropical butters. In this regard, high stearic–high oleic sunflower oil contains disaturated triacylglycerols typically present in CBEs, albeit at a lower concentration than that required to produce a solid fat. Here we have assessed a means to fractionate this oil in order to produce solid fractions that can be used as stearic acid-rich butters appropriate for CBE formulations. Solvent fractionation of high stearic–high oleic sunflower oil was optimised in function of the oil/solvent ratio and temperature. Sunflower stearins with similar melting profiles as cocoa butter were obtained from oils of either 17% or 20% stearic acid in a single step. Different stearin products can be obtained by controlling the oil/solvent ratio and the temperature of fractionation. The use of these fractions as CBE components or confectionery fats is discussed in function of their melting profiles.
Extraction, refining and processingVegetable oils: Production, consumption and tradeSome topical issuesReferences
Although bloom in chocolates and compound coatings has been studied for many decades, the specific mechanisms of fat bloom still remain largely unknown. Furthermore, it is generally considered that the mechanisms for fat bloom formation in chocolate are different than those for compound coatings.
After a brief review of chocolates and compound coatings, we summarize past studies on fat bloom formation in both products. A comparison of the effects of various parameters on bloom formation, either as accelerators or inhibitors, provides insight into the similarities and differences in these phenomena.
Based on this analysis, a global view of the mechanisms of bloom formation in both chocolates and compound coatings is suggested.
The influence of chemical composition on the isothermal cocoa butter crystallization was investigated quantitatively. Apart from the fatty acid and triacylglycerol profile, the amounts of some minor components (diacylglycerols, free fatty acids, phospholipids, soap, unsaponifiable matter, iron, and primary oxidation products) were determined. With the forward model selection technique, a multiple linear regression model was established, showing the influence of chemical characteristics on the different crystallization parameters of the new model to describe the fat crystallization kinetics as developed by Foubert and others (2002). The ratios of saturated to unsaturated fatty acids and monounsaturated to diunsaturated triacylglycerols have the most important effect on the amount of crystallization, the induction time of the 2nd step of the crystallization process, and the order of the reverse reaction. The more unsaturated fatty acids and the more diunsaturated triacylglycerols, the lower the amount of crystallization; the higher the induction time for the 2nd step of crystallization, the lower the order of the reverse reaction. The amount of diacylglycerols has the most important (negative) influence on the rate constant. Other minor components with a rather pronounced influence on different crystallization parameters are the free fatty acids, phospholipids, and traces of soap.
Although cocoa butter (CB) is an ideal fat for use in chocolate, it softens with heat and is not suitable for use in warm climates. CB extenders or improvers, preferably from stearic acid-rich fats, are good candidates to increase the heat-resistance property of CB and chocolate. In the present investigation, one such fat, kokum, is used as an improver to increase the hardness of chocolate. Kokum fat is added in various proportions replacing CB in dark and milk chocolate formulations and its effects on rheology, hardness and triglyceride composition were studied. The results revealed that up to 5% kokum fat addition by weight of the product did not significantly affect the plastic viscosity or yield stress of milk or dark chocolate. Hardness of both dark and milk chocolate increased with increase in addition of kokum fat. The solids fat content at and above 30 °C increased with increase in level of kokum fat with CB, especially at and above 15%. These physical properties are due to increase in 2-oleodistearin triglycerides with addition of kokum fat with CB. The results revealed that kokum fat could be used up to 5% by wt of the product to increase the heat-resistance property of chocolate so that it can be used in warm climates. Copyright © 2004 Society of Chemical Industry
A method of determining cocoa butter equivalents in chocolate and cocoa butter is described. The method relies on a new approach
for interpreting data obtained by triglyceride gas liquid chromatography (GLC). This technique provides information on the
composition of a fat according to the carbon number of the triglycerides (Cn). Examination of the data for a wide range of cocoa butters shows that a straight line relationship between the C50 and C54 contents exists. This relationship has been used as the basis for a quantitative method determining the amount and type of
cocoa butter equivalent added to chocolate. The application of the method to both plain and milk chocolate is described. The
method is also used to determine the amount of milk fat in chocolate.
Palm kernel and coconut oils are the most used of the lauric acid group of oils. The characteristic of this group is their
high content of saturated acids, lauric and myristic, and it is from this feature that their principal uses are derived. Due
to their triglyceride composition, both oils have steep melting curves and melt below body temperature. Their low degree of
unsaturation gives them high oxidative stability. As a result of these properties they are found widely used as hard butters
and in vegetable fat ice-creams, coffee whiteners and similar products. Their use in margarine gives that product an attractive
coolness in the mouth. Coconut oil is also used extensively as a raw material for soaps and detergents and as a body oil.
The oils are susceptible to hydrolytic splitting and to trace metal catalyzed oxidation. They are particularly affected by
contamination with other oils which produce either reduced oxidative stability or, when the contaminant is high melting, an
unacceptable palate cling. Refining is normally done with caustic soda solutions and refining conditions are chosen to minimize
neutral oil losses due to saponification. Physical refining is also practised and is particularly useful for treating palm
kernel oils with high free fatty acid content. To improve their quality and applicability for several uses, both oils are
hydrogenated, fractionated and interesterified in various combinations. Fractionation is done either by dry “pressing” or
with the assistance of detergents or solvents, the highest quality products being obtained using solvents. The relatively
high solubility of the fatty acids can result in effluent problems.
Six cocoa butters with different crystallization induction times and their seed crystals were analyzed for simple lipid composition.
The rapid-nucleating cocoa butter samples had higher concentrations of 1-palmitoyl-2-oleoyl-3-stearoylglycerol and 1,3-stearoyl-2-oleoylglycerol
(SOS), and lower concentrations of the diunsaturated triacylglycerols, 1-palmitoyl-2,3-oleoylglycerol and 1-stearoyl-2,3-oleoylglycerol,
as well as higher stearic acid concentrations within their diacylglycerol fractions when compared to the slow-nucleating samples.
At the early stages of crystallization, under agitation conditions at 26.5°C, cocoa butters solidified into two fractions,
high-melting and low-melting. The low-melting fractions were composed of polymorphs IV and V of cocoa butter, as indicated
by the onset melting temperatures of the endotherms from differential scanning calorimetry. The high-melting fractions, which
had wide melting ranges, had peak maxima of 38.5–52.2°C. Seed crystals isolated at the early stage of crystallization were
characterized by high concentrations of complex lipids, saturated triacylglycerols, saturated fatty acid-rich diacylglycerols,
and monoacylglycerols. The rapid-nucleating seed crystals had higher concentrations of SOS when compared to their respective
cocoa butters. The slow-nucleating seed crystals did not exhibit this characteristic.
Sterol lipids of cocoa butter (cocoa beansLome Tongo) were fractionated into free sterols, steryl esters (SE), steryl glucosides and acylated steryl glucosides (ASG). 4-Desmethyl,
4-methyl and 4,4′-dimethyl sterols or triterpene alcohols, which were isolated as free sterols or which resulted from hydrolysis,
were determined by thin layer chromatography-flame ionization detection and identified by gas chromatography and combined
gas chromatography-mass spectroscopy. Free sterols comprise the main sterol fraction in cocoa butter. Esterified sterols amount
to 11.5% of total sterols and glucosidic sterols to 16.3%. Fatty acids and D-glucose from hydrolysis of esters and glucosides
were analyzed. The fatty acids of SE and ASG are richer in unsaturated fatty acids than cocoa butter total fatty acids.
Preparation of hard palm midfractions (PMF) and its use as a cocoa butter equivalent ingredient were studied. Hard PMF is
obtained by multistep fractionation of palm oil involving dry fractionation (DF) and/or solvent fractionation (SF), usually
using hexane or acetone. From our experience, in acetone, a polar solvent, symmetrical 1,3-disaturated triacylglycerols tend
to selectively crystallize more than nonsymmetrical 1,2- or 2,3-disaturated triacylglycerols, making it suitable for obtaining
the solid midfraction. Unfortunately, triacylglycerols are very soluble in hexane, and temperatures at least 15 degrees lower
than those required for acetone must be used for equivalent crystal yields. On the other hand, DF is a less expensive and
safer process. Thus, multistep fractionation combining DF and SF using acetone was developed to achieve sufficient removal
of high-melting components, and further enrichment of 1,3-dipalmitoyl-2-oleoylglycerol and the hard PMF was obtained by triple-step
fractionation of palm olein or double-step fractionation of soft PMF. Compared to conventional hard PMF, this hard PMF had
a steeper melting curve and better snapping and sharp-melting qualities when used in chocolate. Heat resistance of the hard
PMF chocolate was similar to the conventional hard PMF chocolate, and its bloom resistance could be improved by adding polyglycerol
fatty acid esters.
Solvent-free lipase-catalyzed incorporation of stearic acid in palm olein by the 1,3-regiospecific Novo Lipase Lipozyme IM20
resulted in the formation of a complex mixture of fatty acid glycerides and free fatty acids. The stearoyl incorporation in
palm olein gave rise to the formation of 39.3% of the desired cocoa butter-like triglycerides in the fatty acid glyceride
portion, namely distearoyl-oleoyl-glycerol (SOS), palmitoyl-oleoyl-stearoyl-glycerol (POS) and dipalmitoyl-oleoyl-glycerol
(POP). A combination of fractionation steps involving initially the removal of free fatty acids (FFA) from the product mixture
by steam distillation under vacuum, followed by fractional crystallization of the fatty acid-free glycerides in hexane and/or
acetone, gave a fat, whose triglyceride composition and melting profile were comparable to that of cocoa butter as adduced
by reversed-phase high performance liquid chromatography (HPLC) and differential scanning calorimetry (DSC). The yield of
the cocoa butter-like fat was approximately 25% of the weight of the original palm olein.
A program of work is in progress to establish the levels and ranges of fatty acids and other components present in the major
edible vegetable oils. Authentic samples from the major producing areas for such oil have been obtained and analyzed. In the
case of palm oil, ranges of the fatty acid composition and of the acids at the triglyceride 2-position, have been obtained
for about 40 samples. These data were used to calculate enrichment factors, and triglyceride carbon number compositions, using
a small computer program. Comparison with experimentally determined carbon number compositions were then made. Good correlations
were found for whole unadulterated oils, but not for oil fractions. Unfortunately, these differences were insufficient to
detect contamination of palm oil by 10 or 20% levels of other oils, or of palm fractions. Compositional ranges of sterols
and tocopherols have also been determined on a selection from the original set of palm samples. Work on sunflower seed and
groundnut oils has followed the same lines, particular attention having been paid to linolenic acid and, in the case of groundnut
oil, also erucic acid, levels. Some groundnut kernels were found to have an oil with a component which cochromatographed with
methyl erucate during fatty acid determination. This unknown constituent was studied by gas chromatography-mass spectrometry,
and is thought to comprise a mixture of epoxy fatty acids. Analysis of the triglyceride fraction isolated from groundnut oil
by thin layer chromatography removes this unknown constituent, and simplifies interpretation of the fatty acid composition
of groundnut oil.
The polymorphism and phase transitions of cocoa butter (CB) have been reexamined separately by differential scanning calorimetry
(DSC) and X-ray diffraction as a function of temperature (XRDT) at scanning rates between 0.1 to 5°C/min and 0.1 to 2°C/min,
respectively. A new instrument, which allowed simultaneous DSC and XRDT recordings from the same sample by taking advantage
of the high-energy flux of a synchrotron, was employed for characterization of the intermediate phase transitions. These techniques
allowed us to confirm the existence of the six polymorphic forms of CB (called I to VI) by in situ characterization of their formation in the DSC + XRDT sample holder. A detailed study of Form I structure led us to propose
a liquid-crystal organization in which some of the chains displayed sharp long-spacing lines (d001=52.6±0.5 Å) and a β′ organization (4.19 and 3.77 Å), while the others remained unordered with broad scattering (maxima at
about 112 and 36.5 Å). The organization of this liquid crystalline phase is compared to that of fat and oil liquids. This
liquid crystalline phase progressively transformed on heating into a more stable phase (Form II, α type, d001=48.5±0.5 Å and short-spacing at 4.22 Å). Form III was only observed in a sharp temperature domain through its specific short-spacings.
The existence of the six species has been essentially related to the crystallization of monounsaturated triacylglycerols (TAG),
while trisaturated species were found partly solid-soluble in these six polymorphic forms. An insoluble fraction crystallized
independently of the polymorphism of the monounsaturated TAG in a separate phase with long-spacings that were either of the
α (49.6±0.5 Å) or β (44.2±0.5 Å) form. In mixture with Form V, this fraction melts and solubilizes in the liquid phase at
37.5°C. Isolation of these high-melting crystals shows a melting point of about 50°C. High-performance liquid chromatography
analysis of this fraction confirmed an increase from 3.0 to 11.3% of saturated TAG and their association with part of the
1,3-stearoyl-2-oleoylglycerol preferentially to 1-palmitoyl-2-oleoyl-3-stearoylglycerol and (1,3-palmitoyl-2-oleoylglycerol).
The performances of four chromatographic methods in combination with multivariate statistical data analysis were compared for the determination of cocoa butter equivalents (CBEs) in mixtures with cocoa butter (CB). The sample set analysed consisted of 42 different CBs, including specific crops (soft South American and hard Asian CB types), and 21 commercially available CBEs, including several types of illipé-containing fats. From these pure samples about 250 CB/CBE mixtures were prepared containing between 5% and 20% CBE addition. The triglyceride (TG) composition of the blends was analysed by packed column gas-liquid chromatography (GLC), capillary GLC and high-performance liquid chromatography. In addition, the fatty acid profile was determined by capillary GLC. Data generated by packed-column GLC were evaluated by a graphical procedure, whereas multiple linear regression analysis was applied to data from high-resolution methods. The calibration model that most efficiently minimised the error of prediction was based on a combination of fatty acid and TG data as input variables. The average error of prediction was estimated to be 2.3% CBE in CB, without prior knowledge of either the CB or the CBE composition. Recalculated for a chocolate with a fat content of 20% the error estimate would equal 0.5% CBE in the finished product.
As are traditional fractionation technologies, static dry fractionation is a highly reliable technology for the consistent
production of good-quality palm kernel stearin (PKS) for use as cocoa butter substitute (CBS) after total hydrogenation. A
new process route now permits the production of unhardened yet high-quality CBS. Also an increase in total stearin yield can
be achieved, via a successful refractionation of palm kernel olein. DSC analysis together with pilot static fractionation trials on the palm
kernel olein indicates that a cooling water temperature that is too low (e.g., 17°C) may result in the quick formation of
unstable crystals that are possibly later converted to a more stable form. The resulting mixture of crystals with a possibly
different polymorphic structure is easily squeezed through the filter cloth during filtration, whereas a slower, but more
homogeneous co-crystallization occurs at higher temperature (18°C or higher) and results in a much more stress-resistant slurry.
Polarized light microscopy analysis confirmed that crystal size is not the only determining factor for a successful filtration.
The total two-stage static fractionation of palm kernel oil (PKO) [iodine value (IV) 18] on a pilot scale results in the following
three end products: PKS IV 5 (yield: 29%, for direct use as CBS), PK olein IV 27 (yield: 58%), and PKS IV 7 (yield: 13% for
use as CBS after full hydrogenation). The unhardened PKS IV 5 has outstanding melting and crystallization properties, comparable
to traditional hydrogenated stearin fractions. Therefore, rather than the higher stearin yield, the reduced hydrogenation
capacity is most probably the most important benefit of the two-stage static fractionation process.
The fatty acids at the sn-2 position and the sterol composition of cocoa butter and three common cocoa butter equivalents
(CBE), namely Coberine, Choclin and Calvetta, were studied comparatively, in order to develop a sensitive method for detecting
CBE in chocolate. Differences observed in the composition of saturated fatty acids at position-sn-2 present some interest
in detecting CBE in chocolate. Differences found in 4-desmethyl and 4-methylsterol compositions, although quite significant,
did not present any practical interest because of the relatively small amounts present in CBE. The 4,4′-dimethylsterol or
triterpene alcohol fraction was found to have a potential for determining CBE in chocolate. Thus, the triterpene alcohols
of Coberine were further fractionated on argentation thin layer chromatography (TLC) and analyzed by gas liquid chromatography
(GLC) and gas chromatography-mass spectrometry (GC-MS). α-Amyrin was found in 48.2% of the triterpene alcohols of Coberine
and was absent from cocoa butter. Cycloartenol, the main 4,4′-dimethylsterol of cocoa butter, and α-amyrin were well resolved
on an OV-17 glass capillary column.
Twelve commercially available triacylglycerol lipase preparations were screened for their suitability as catalysts in the interesterification of palm oil mid fraction and ethyl stearate to form a cocoa butter equivalent. Five fungal lipase preparations were found to be suitable. The hydrolytic activity of the commercial lipase preparations was tested with sunflower seed oil and was independent of their interesterification activity. The operational stability of three of the preparations most suited for production of cocoa butter equivalents was examined. The amount of a commercial lipase preparation loaded onto a support was surveyed for optimum short-term catalytic activity.
The influence of solvent concentration on the reaction rate and the purity of the product was examined at two temperatures. The optimum solvent concentration at 40°C was 1–1.5 grams of solvent/gram of substrate; at 60°C, the rate of interesterification diminished and the purity of the product decreased with increasing amounts of solvent.
Four of the commercial lipase preparations found to be suitable interesterification catalysts were immobilized on five supports and their ability to catalyze the interesterification of a triglyceride and palmitic acid or ethyl palmitate was measured. The choice of support and substrate form (esterified or free fatty acid) greatly affected the catalytic activity. Some preparations were more affected by the choice of support, others by the form of the substrate. No preparation yielded maximum activity on all supports, and no support was found which produced an immobilized enzyme preparation of high activity with every commercial lipase preparation. Caution is advised in transferring observations about the suitability of a support from tests on one commerical enzyme preparation to others; individual testing is required.
In the search for economical cocoa butter alternatives, palm and lauric oils have emerged as important source oils in the development of hard butters. Based on the method presented for categorizing hard butters, the lauric oils, primarily palm kernel and coconut, can be modified by interesterification and hydrogenated to yield lauric cocoa butter substitutes (CBS) which are both good eating and inexpensive. Fractionation, although adding to the cost of production, can provide lauric hard butter with eating qualities virtually identical to cocoa butter. Unfortunately, one factor identified with the lauric oils is their very low tolerance for cocoa butter.
Palm oil, on the other hand, has been identified as a valuable component in all types of cocoa butter alternatives. It is a source of symmetrical triglycerides vital in the formulation of a cocoa butter equivalent (CBE). It can be hydrogenated or hydrogenated and fractionated to yield hard butters with a limited degree of compatibility with cocoa butter, allowing some chocolate liquor to be included in a coating for flavor enhancement. Palm oil is used with lauric oils as a minor component in interesterified lauric hard butters, as well as functioning as a crystal promoter in coatings formulated with a fractionated lauric CBS. While palm oil’s importance and flexibility have been duly noted, some important concerns remain from a market perspective. The fact that the CBE fats are very expensive suggests they offer limited cost savings compared to cocoa butter. The potential for CBE products is still questionable in those countries where chocolate labeling standards preclude the use of vegetable fats other than cocoa butter. The nonlauric CBS products, while cheaper than the CBE types and able to tolerate limited levels of cocoa butter, do not exhibit the level of eating quality characteristics present in the lauric hard butters.
Some challenges remain for today’s oil chemists. An economical nonlauric CBS, made predominantly from palm oil, possessing the eating quality of a fractionated lauric CBS and exhibiting good compatibility with cocoa butter would be met with considerable interest by the chocolate and confectionery industries. As for the lauric oils, it would seem reasonable to assume that greater cocoa butter compatibility, if attainable, could enhance their potential for gaining even greater acceptance by confectionery manufacturers currently using pure chocolate. As for the CBE products, the major issue is cost. If the cost of a CBE could be reduced to a level which would allow a CBE to compete with the nonlauric and lauric cocoa butter substitutes, a major advancement in the evolution of cocoa butter alternative fats will have been achieved.
The seeds of nineHerrania and nineTheobroma species were surveyed for fatty acid, sterol, tocopherol and tocotrienol compositions. Principal component and cluster analyses
suggested that these analytes could be used collectively as chemotaxonomic criteria to differentiate theHerrania species from theTheobroma species, as well as to provide subgroup distinctions within each genus for comparison to the existing classification schemes.
African shea butter, a vegetable fat produced from the seeds of Vitellaria paradoxa C.F. Gaertn. (syn. Butyrospermum parkii L.), Sapotaceae, is a unique natural product of African countries and is of great nutritional and commercial significance. The volatile compounds of various shea butter samples were analysed to investigate the influence of differences in manufacturing (boiling/roasting or combined procedures) on the headspace composition and with regard to the different origin of the samples. Volatile compounds were analysed by using gas chromatography–mass spectrometry after headspace solid phase microextraction (HS-SPME). Qualitative and semi-quantitative patterns of volatile compounds investigated in this study were composed of fatty acids degradation products, e.g. acetic and hexanoic acid, carbonyl compounds (hexanal, heptanal, trans-2-heptenal, 2,4-heptadienal), 2-pentylfurane, processing compounds like furfural as well as glycerol and residue compounds from technical processing steps including milling. Comparison of the volatile profile of 16 different shea butters from four African countries showed that processing steps including drying of kernels before producing the fat and additional roasting procedures influence shea butter headspace composition significantly.
Egyptian mango seeds were collected as wastes from local fruit processing units and the kernels were separated and dried. This study was carried out on mango seed kernels to clarify their proximate composition, amino acids, phenolic compounds and the characteristics of the extracted oil including unsaponifiable matter constituents, lipid classes and fatty acid composition. Mango seed kernels contained a considerable amount of total phenolic compounds, total lipid, unsaponifiable matter, and a low amount of crude protein, but the quality of protein was good because it was rich in all essential amino acids. Eight phenolic compounds were identified; tannin and vanillin were in highest amounts. Unsaponifiable matter showed the occurrence of high amounts of squaline followed by sterols and tocopherols. Stearic acid was the main saturated fatty acid, while oleic acid was the major unsaturated fatty acid in all lipid classes. The fatty acid composition of total lipid and neutral lipid was similar, while phospholipid had a high amount of palmitic, linoleic and linolenic acids.
Fat crystallisation behaviours in dark chocolates from varying particle size distribution (PSD) (D90 of 18, 25, 35 and 50 μm) was studied, yielding products from different temper regimes (optimal temper, over-temper and under-temper), and their effects on mechanical properties and appearance evaluated. Microstructures of derived products were determined using stereoscopic binocular microscopy. Wide variations in mechanical properties and appearance were noted in products from different particle size and temper regimes. Particle size (PS) was inversely related with texture and colour, with the greatest effects noted in hardness, stickiness and lightness at all temper regimes. Over-tempering caused significant increases in product hardness, stickiness with reduced gloss and darkening of product surfaces. Under-tempering induced fat bloom in products with consequential quality defects on texture, colour and surface gloss. Micrographs revealed variations in surface and internal crystal network structure and inter-particle interactions among tempered, over-tempered and under-tempered (bloomed) samples. Under-tempering caused whitening of both surface and internal periphery of products with effects on texture and appearance. Thus, attainment of optimal temper regime during pre-crystallisation of dark chocolate was central to the desired texture and appearance as both over-tempering and under-tempering resulted in quality defects affecting mechanical properties and appearance of products.