Avi Shpigelman

• PhD
• Professor (Associate) at Technion – Israel Institute of Technology

Pectin is a common, extremely complex and process sensitive polysaccharide in plant cell walls with many uses as an additive in the food and biomedical industry. Process induced chemical changes in pectin result in various effects on its functionality. An in-depth study is presented of the effects of thermal compared to HP/HT (high hydrostatic pres...

We investigated the mechanisms of the protection conferred by sugars to epigallocatechin-3-gallate (EGCG) against deterioration. Additionally, we present a rapid method for evaluating the deterioration rate of EGCG using absorbance spectroscopy. We found that various sugars provided different levels of protection at identical weight percentage, and...

Delivery of sensitive water-soluble compounds in foods is an important challenge. (−)-Epigallocatechin-3-gallate (EGCG), the major catechin in green tea, is a potent antioxidant with numerous attributed health benefits. However, its sensitivity to oxidation limits its enrichment in the diet for preventive medicine. We have studied the possibility o...

(-)-Epigallocatechin-3-gallate (EGCG), which has been attributed with numerous health benefits, is an oxidation sensitive, water soluble polyphenol. We have recently shown that heat-denatured β-Lactoglobulin (β-Lg) forms nanoparticles (<50 nm) with EGCG, which confer considerable protection to EGCG against oxidative degradation, useful for clear be...

New research shows that flavonoids containing a pyrogallol group in ring B react with amino acids at 37°C, forming ammoniated derivatives and aldehydes. Despite this, studies on these reactions and the activity of the resulting ammoniated flavonoids (NH 2 ‐flavonoids) are scarce. This study investigates the amination of (+)‐dihydromyricetin (DMY),...

A class of flavonoid aminated derivatives that had been consistently overlooked in literature was shown to be formed as artefacts in cell culture medium. In this study, 34 flavonoids from different subclasses were incubated in Dulbecco's modified Eagle's Medium (DMEM) at 37°C for 2 h to identify the reaction mechanism behind aminated derivatives fo...

This Special Issue, titled "Polyphenolic Antioxidants in Food", welcomes manuscripts focusing on the diverse role of polyphenol compounds within food systems. We invite original works that address the identification, characterization, and mechanisms of antioxidant activity of polyphenols, studied using in vitro and in vivo methodologies. The submit...

Lignans are a group of plant phenolic compounds with various technofunctional and health-promoting properties. They can be found in oilseeds (291.7–2513 mg/100 g), nuts, vegetables, fruits, and alcoholic and nonalcoholic drinks. The most common structural representative feature of lignans’ backbone is a dimeric phenylpropanoid, which consists of tw...

Introduction Safe and efficient treatment of organic waste is crucial to developing a sustainable food system around the world. Soil biosolarization (SBS) is a soil treatment technique that can use organic solid wastes to treat the soil in a way that is alternative to the use of chemical fumigants to improve soil fertility in agriculture. Methods...

https://www.ift.org/news-and-publications/food-technology-magazine/issues/2023/june/columns/processing-pef-pulsing-with-promise

The utilization of natural blue pigments in foods is difficult as they are usually unstable during processing and the commonly applied pH. The current study focuses on natural blue pigment, possessing antioxidant properties, found in Arthrospira platensis (spirulina), and phycobiliproteins (PBP). These pigments are a complex of conjugated protein a...

Polyphenols are acknowledged as health-promoting compounds, yet also known for their low bioavailability. Thus the evaluation of their bioaccessibility, as a principle parameter for bioavailability, is important. In-vitro digestion is a common method for assessing polyphenol bioaccessibility, yet, the method conditions don’t address the potential i...

Pressure based technologies are a major sub-group of novel and alternative techniques that can be used for the processing and preservation of biomaterials. Such technologies utilize, at least partially, the effect of pressure on the physical properties to obtain microbial inactivation, enzymatic (de)activation, extraction, or other required effects...

Various groups of functional compounds are present in plants as well as in waste and side streams of bioindustries. The efficient and economically viable valorization of such compounds often depends on the processing of such plants and waste (or side) streams to allow their extraction. In the current chapter, we will shortly present several groups...

Polyphenol stability in processed food affects sensorial and health-promoting properties. Thus, understanding the effects of various food components on polyphenols degradation, as a function of their chemical structure, can contribute to optimal product engineering. The current study focuses on the impact of polyphenol structure on polyphenol-prote...

The potential of high-pressure homogenization (HPH) to allow the production of a fermented potato protein isolate-based yogurt alternative with low and high oil concentration was investigated. The yogurt alternatives containing different oil concentrations (1.5%, 3%, and 10%) were obtained by inoculating the homogenized (0.1 MPa, 30 MPa, and 200 MP...

Gelation is an important techno-functionality for novel protein sources. Yet, only one study has focused on the gelling potential of concentrates from the microalgae Spirulina, despite its potential as a sustainable protein source. That study reported relatively low stiffness, hindering the application. The current study focuses on Spirulina protei...

(Ultra) high-pressure homogenization ((U)HPH) is one of the emerging technologies being studied and developed for various applications in the food industry. (U)HPH was suggested as an effective tool for achieving microbial safety and extending the product shelf life of liquid foods in a continuous process while minimizing some negative attributes o...

The demand for alternatives to milk-based yogurts with high acceptance and functionality has been increasing in recent years. Yet, many plant-based proteins suffer from limited techno-functional properties such as poor solubility, color, and other sensory properties. The utilization of high-pressure homogenization (HPH) has been suggested as a tool...

Polyphenols are the most important phytochemicals in our diets and have received great attention due to their broad benefits for human health by suppressing oxidative stress and playing a protective role in preventing different pathologies such as cardiovascular disease, cancer, diabetes, and obesity. The stability of polyphenols depends on their e...

Flavonoids are polyphenolic natural compounds with suggested health-promoting properties and impact on sensory aspects. Processing, as well as mastication of plant-based food, can allow interactions between flavonoids and plant cell wall material (CWM). Pectin is a cell wall polysaccharide, present in all plant-based products, and used in a wide ra...

Numerous human conditions can benefit from diets rich in proteins and bioactives, such as capsaicin (CAP), yet their effective delivery is a sensorial, scientific and technological challenge. This study hypothesized that CAP can form various complexes with native bovine alpha-lactalbumin (holo-ALA) and decalcified-ALA (apo-ALA). Calorimetric and sp...

Anthocyanins are often associated with health benefits. They readily degrade during processing and storage but are also dependent on the matrix conditions. This study investigated how strawberry anthocyanins are affected by preservation technologies and a relatively protein-rich kale juice addition during storage. A strawberry–kale mix was compared...

Polyphenolic compounds are known to interact with cell wall materials (CWM) and other polyphenols by hydrogen bonds and hydrophobic interactions. The impact of pressure on such interactions was studied in mono- and multi-component model systems. The results reveal that pressure affects polyphenol–CWM and polyphenol-polyphenol interactions. Pressure...

Pectin is well-known plant-based hydrocolloid extensively used in food and beverage industry for formation and/or enhancement of product texture and stability. Versatile functionalities of different pectin types (e.g., gelling, thickening, colloidal stabilization) are predetermined by their structure. The aim of this work was to explore possibility...

There is a need to better understand the possible anti-nutritional effect of food stabilizers on the digestibility of important macronutrients, like proteins. This study hypothesized that the anionic nature of κ-, ι-, λ-, Carrageenan (CGN) and xanthan gum directs their interactions with food proteins leading to their subsequent attenuated digestive...

Potato protein isolate (PPI), a commercial by-product of the starch industry, is a promising novel protein for food applications with limited information regarding its techno-functionality. This research focused on the formation of both thermal and high-pressure gels at acidic and neutral pH levels. Our results reveal that physical gels are formed...

Polyphenols are suggested to hold various health benefits, however, their absorption is often poor. The impact of processing (unprocessed, pasteurization (PT), high-pressure (HPP)), pH (6.5, 2.5) and added cell-wall was studied using semi-dynamic in-vitro digestion of a model polyphenol extract (PE). Structure-dependent bioaccessibility was observe...

Due to health-beneficial effects of polyphenols, their stability and bioaccessibility in strawberry puree as influenced by processing (thermal, pulsed electric field (PEF), high pressure processing (HPP)) and by combination with relatively protein-rich vegetable juice (kale) was investigated. Soluble strawberry anthocyanins decreased in the presenc...

The food additive carrageenan (E407) (CGN) is a family of sulphated galactans widely used in numerous processed foods, including dairy. There are various indications that CGN may hinder digestive proteolysis. This study sought to link CGN macromolecular characteristics to its implications on digestive proteolysis of whey protein isolate (WPI) in to...

Polyphenols play an important role in the sensorial and health-promoting properties of fruits and vegetables and display varying structure-dependent stability during processing and shelf-life. The current work aimed to increase the fundamental understanding of the link between the stability of polyphenols as a function of their structure, presence...

Understanding reaction kinetics at elevated pressures is of importance for the development of pressure-based technologies and especially for hyperbaric storage (HS), a potential alternative for the energy-consuming refrigeration. The effect of pressure on degradation kinetics of a polyphenol, Epigallocatechin-gallate (EGCG), was explored at pressur...

Protein–polyphenol interactions can possibly be affected by processing and modifying the product stability, the digestive fate and stability during shelf-life of proteins and polyphenols. In this study, the combined effects of the addition of a polyphenol-rich matrix (strawberry) and the preservation technology (thermal, PEF, HPP) on kale juice (K)...

The increasing awareness of lifestyle implications on our well-being resulted in a great interest in health-promoting aspects of food and food components, and their role in the prevention of chronic diseases. Polyphenols are suggested to be correlated with numerous health benefits, however, their bioaccessibility and bioavailability, which can alte...

Cellulose acetate is one of the most important cellulose derivatives. The use of ionic liquids in cellulose processing was recently found to act both as a solvent and also as a reagent. A recent study showed that cellulose dissolution in the ionic liquid 1-ethyl-3-methylimidazoliumacetate (EMIMAc) mixed with dichloromethane (DCM) resulted in contro...

Strawberry drinks are considered as functional food products due to their high content of health-promoting compounds such as polyphenols. High-pressure homogenization (HPH) results in microbial inactivation while significantly disrupting the plant matrix. This study evaluated the effect of HPH (up to 200 MPa) and number of cycles (at 200 MPa) on th...

The loss of color pigment is an important quality factor of food products. This work aimed to systematically study, in purified model systems, the influence of anthocyanins’ structure (by increasing the size of the conjugated sugar) and the presence of ascorbic acid on their stability and spectral properties during storage at two pH levels relevant...

Diversity of food-grade carrageenan and rising levels of exposure to carrageenan mandate re-evaluation of its safety for the entire population.

The aim of the presented study was to evaluate the potential of a headspace fingerprint as a multivariate intrinsic indicator for monitoring temperature history variation that can occur, for example, during in-pack food processing at the product level. Using solid-phase micro-extraction gas chromatography mass spectrometry (SPME-GC–MS), we monitore...

Flavonols are natural compounds that are widely distributed in fruits and vegetables and suggested to have beneficial health effects. During processing of plant-based food products as well as during mastication, the flavonols that usually located within the cell can be released and interact with other plant compounds such as pectin - a part of the...

Carrageenan (CGN), a family of marine polysaccharides isolated from seaweeds, has been at the heart of considerable debate in recent years. To date, CGN is generally recognized as safe based on a history of safe use, various acute toxicology studies and some recent chronic toxicology tests. This review offers readers an overview of evidence on CGN...

Changes in the stability during shelf life of riboflavin, vitamin C and the antioxidant capacity of (ultra) high pressure homogenized ((U)HPH) milk were explored. With increasing pressures, a decrease of up to 50% in the degradation rate of riboflavin was observed, likely due to an indirect effect induced by (U)HPH leading to increased scattering a...

The influence of polysaccharides on texture and salt release from model fresh cheese was examined by the addition of 0.04 %wt. polysaccharides; (kappa carrageenan (κ-CG), iota carrageenan (i-CG), locust bean Gum (LBG), sodium alginate (SAG) or low acyl gellan (LAG)) prior to milk renneting. The addition of LAG and κ-CG to the milk, prior to cheese...

Mandarins are a member of the Citrus genus and are the focus of growing commercial interest, with satsuma mandarins (Citrus unshiu) and the common mandarin (Citrus reticulata Blanco) being the most important mandarin varieties. The possible health benefits and functional properties of those fruits are often associated with the antioxidative functio...

Litchi pericarp procyanidins (LPP) are dietary supplements with high antioxidant activities, yet with a poor oral bioavailability and efficacy. Lactobacillus casei (L. casei-01) can transform flavan-3-ols from litchi pericarp and increase their antioxidant ability; thus, L. casei-01 with LPP was administered to rats for four and eight weeks to stud...

Citrus is a major processed crop that results in large quantities of wastes and by-products rich in various bioactive compounds such as pectins, water soluble and insoluble antioxidants and essential oils. While some of those wastes are currently valorised by various technologies (yet most are discarded or used for feed), effective, non-toxic and p...

From ancient times, species from Allium genus were used for both culinary and medicinal applications. Most of the beneficial health promoting properties of these species were attributed to their high content of bioactive organosulfur compounds (OSCs). The OSC, consequently attracted interest from food and pharmaceutical industries to be used as add...

The use of protective protein-based nanovehicles to deliver hydrophobic nutraceuticals raises important questions regarding their consequent bioavailability compared to that inside fat, or in its presence. To answer that, vitamin-D3 was chosen as a model lipophilic-bioactive, re-assembled casein micelles (rCM) as a protein-based nanovehicle and 0%...

Mango is a commercially important and popular tropical fruit. While there is a growing commercial interest to incorporate fruit pieces in juices and soft drinks, such implementation for mango pieces is impaired by the sensitivity of the pieces texture during beverage processing (i.e., thermal treatment) and shelf life. In this work, we have evaluat...

This paper addresses to what extent mango purée macroscopic properties (consistency) is related to its particle physical properties such as mesoscopic (particle size) and microscopic (morphology) properties. To manipulate mango purée particle sizes, high pressure homogenization (HPH) was used. Commercial fungal and bacterial (cell wall) polysacchar...

Pectin, a plant cell wall polysaccharide, is a natural multifunctional ingredientwhich imparts textural and rheological properties to a wide range of food systems. Up to the last decade, most pectin blank applications stemmed from its gel-forming ability. Nowadays, pectin is gradually gaining acceptance as an effective emulsifier in numerous food a...

Recent studies showed that the functional properties of food suspensions are determined both by the plant-based particles and the serum properties, and the ratio between these two phases. This paper addresses the effect of enzymatic and high-pressure homogenization (HPH) treatments on the properties of bio-polymers present both in mango puree serum...

Rheological properties of cell wall suspensions strongly depend on particle size and particle-particle interactions. In the present study, an experimental method was developed to study the effect of particle elasticity and electrostatic interactions on the rheological properties of cell suspensions. Enzymes were used to selectively depolymerize the...

In industry, prior to the disruption of the mango fruit, endogenous structural determining enzymes, such as pectin methylesterase (PME) and polygalacturonase (PG) to name a few, are inactivated by a thermal treatment, i.e., blanching, to ensure prevention of enzymatic changes during storage. After purée preparation from blanched fruit, additional e...

Knowing that we have not inherited the Earth from our ancestors but borrowed it from our children, waste management is receiving a greater focus. At present pectin, which is an important functional ingredient in the food industry, is commercially obtained from limited sources, mostly from the waste of apple and citrus industry. Currently, mango pee...

The present invention is directed to co-assembled nanoparticle composition comprising denatured β-lactoglobulin and at least one nutraceutical compound, specifically polyphenols, such as EGCG, compositions comprising same and methods of preparing thereof.

Recombinant kiwi pectin methylesterase inhibitor (rPMEI) with a six-histidine tag at the C-terminus was successfully expressed in Pichia pastoris GS115 strains. rPMEI was purified using pectin methylesterase (PME)-CNBr-affinity chromatography or nickel affinity chromatography. The purified rPMEI had a slightly higher molecular weight than the kiwi...

Abstract The importance of common beans (Phaseolus vulgaris) in addressing food insecurity cannot be underestimated. However, their utilization is hampered by development of the hard-to-cook (HTC) defect i.e. the inability of cotyledons to soften sufficiently within a reasonable time during cooking, presence of flatulence causing oligosaccharides,...

The objective of this work was to evaluate the possibility of using mango endogenous pectinases to change the viscosity of mango purée. Hereto, the structure of pectic polysaccharide and the presence of sufficiently active endogenous enzymes of ripe mango were determined. Pectin of mango flesh had a high molecular weight and was highly methoxylated...

The objective of this work was to extract and evaluate some functional properties (gelling and emulsification capacity, acidified milk drink stabilization) of pectin extracted from mango peel using an acidic ion chelator (citric acid) (pH 2.5, 2 h at 80 °C). The novel extraction method resulted in a high yield of pectin (MPP – mango peel pectin) ha...

Naringin, a glycosylated polyphenol of the flavanones class and its aglycone, naringenin, have been shown to possess many health benefits, therefore they show promise for supplementation of staple foods and beverages, as a mean of preventive medicine. Major obstacles to the successful implementation of these flavanones as nutraceuticals are their l...

The objective of this research was to evaluate whether mango peel is a potential source of functional cell wall polymers. To reach this objective, the native pectin polymers (NPP) extracted as alcohol insoluble residue from mango peel, were characterised in terms of uronic acid content, degree of methoxylation, neutral sugar content, and molar mass...

The occurrence of the hard-to-cook (HTC) defect in legumes is characterized by the inability of cotyledons to soften during the cooking process. This phenomenon may be influenced by pectin properties. The objective of this study was to characterize the pectic polysaccharides comprised in the alcohol insoluble residue (AIR) extracted from easy-to-co...

This study aimed at understanding softening in Jonagold apple (Malus × domestica Borkh.) fruits, by investigating pectin modifications and the evolution of pectin-modifying enzymes during postharvest storage and ripening. Jonagold apples were harvested at commercial maturity and stored at different temperatures and controlled atmosphere conditions...

Pectin is a common, heterogeneous, and structurally complex polysaccharide present in plant cell walls that is naturally present in staple foods and commonly used in the food and biomedical industry. Pectin is known to be sensitive to process induced chemical changes that can result in various effects on its functionality. This worked aimed at bett...

The natural consistency of processed tomato products arises from cell wall particles and the interactions between them. In this study, ion exchange resins were used to investigate these interactions. Two types of resins were used, a hydrogen form cation exchange resin and an anion resin in the hydroxide form. Serum phase of tomato suspensions were...

Abstract The use of Fourier transform infrared (FT-IR) spectroscopy as a method for routine analysis of the degree of methylesterification (DM) of pectin was validated. The relationship between the ratio of the intensity of the peak at around 1740 cm-1 (due to ester carbonyl group stretching) to the sum of the intensities of the peaks at around 174...

To shed new light on the mechanisms of saccharide stereochemistry effect on macromolecules in aqueous solutions, we studied the effect of three monosaccharide stereoisomers, glucose, galactose, and mannose, on the swelling of Poly(N-isopropylacrylamide) (PNIPA) hydrogels. We equilibrated PNIPA hydrogels in sugar solutions of different concentration...

To illuminate the impacts of sugar concentration and stereochemistry on protein protection we used attenuated-total-reflectance Fourier-transform infrared-spectroscopy (ATR-FTIR) to study the effects of four aldohexoses on poly-N-isopropylacrylamide (PNIPA) phase transition. Protein stability in aqueous solutions is essential in numerous fields, pr...

Protein stability in aqueous solutions is important in numerous fields, particularly biotechnology and food-science. To shed new light on the protective effect of carbohydrates on proteins, we studied saccharide-structure effects in aqueous solutions on the coil-to-globule transition occurring at the lower critical solution temperature (LCST) of po...