Effect of solvents in extracting polyphenols and antioxidants of selected raw vegetables

Winemaking generates large amounts of wine pomace, also called grape pomace This by-product has attracted the attention of food scientists and the food industry, due to its high content in nutrients and bioactive compounds This review mainly focuses on the different published approaches to the use of wine pomace and its functions in the food industry Traditionally, wine pomace has been used to obtain wine alcohol, food colorings, and grape seed oil More recently, research has focused in the production of other value-added products, such as extracts of bioactive compounds, mainly phenols, recovery of tartaric acid, and the making of flours The most common functions associated with wine pomace products are their use as antioxidants, followed by their use as fortifying, coloring, and antimicrobial agents These products have mainly been applied to the preparation of meat and fish products and to, a lesser extent, cereal products

https://onlinelibrary.wiley.com/doi/pdf/10.1111/1541-4337.12238

Applications of Wine Pomace in the Food Industry: Approaches and Functions

Mitigation strategies of acrylamide, furans, heterocyclic amines and browning during the Maillard reaction in foods.

Citrus juices are widely consumed due to their nutritional benefits and variety of pharmacological properties. Non-enzymatic browning (NEB) is one of the most important chemical reactions responsible for quality and color changes during the heating or prolonged storage of citrus products. The present review covers various aspects of NEB in citrus juice viz. chemistry of NEB, identifiable markers of NEB, analytical methods to identify NEB markers and ways to improve the quality of citrus juice. 2,5-Dimethyl-4-hydroxy-3(2H)-furanone (DMHF) is one of the promising marker formed during browning process with number of analytical methods reported for its analysis; therefore it can be used as an indicator for NEB process. Amongst analytical methods reported, RP-HPLC is more sensitive and accurate method, which can be used as analytical tool. NEB can be prevented by removal of amino acids/ proteins (via ion exchange treatment) or by targeting NEB reactions (e.g. blockage of furfural/ HMF by sulphiting agent).

/pdf/non-enzymatic-browning-in-citrus-juice-chemical-markers-50jyrnr67a.pdf

Non-enzymatic browning in citrus juice: chemical markers, their detection and ways to improve product quality

Positive and negative effects of polyphenol incorporation in baked foods.

Inhibition of pyrazine formation by natural antioxidants and the foods containing them was measured in a microwaved glucose/glycine model system. Inhibition of lipid oxidation by the same materials was assayed in both bulk and emulsion systems. Pyrazines were determined by solid-phase micro extraction followed by GC. Lipid oxidation volatiles were assayed by polyamide fluorescence produced by either a bulk oil display or a hematin- or 2,2′-azobis-(2-amidino=propane) dihydrochloride-accelerated lecithin or fish oil emulsion. It was shown that (i) the inhibition of pyrazine formation depends on high concentrations of water-soluble antioxidants; (ii) such antioxidants occur naturally in some foods and are usually polyphenols; (iii) during pyrazine inhibition, oxidized polyphenols show enhanced nonfluorescing browning similar to enzymic browning products; (iv) monophenols, which structurally cannot form quinone polymers on oxidation, inhibit pyrazines with less browning; (v) during the final pyrazine-forming phase of the Maillard reaction, polyphenolics and reducing agents such as glutathione and ascorbic acid are partially consumed with some nutritional loss; (vi) fruit powders of grape seed, grape skin, and red wine are highly pyrazine-inhibitory, steeped blueberry strongly so, but plum purees are moderately pro-pyrazine, and freeze-dried vegetables strongly pro-pyrazine; and (vii) black and green tea infusions are highly inhibitory, whereas spices have mixed effects.

Amy Lynch

Papers

Modification of maillard browning in a microwaved glucose/glycine model system by water-soluble natural antioxidants and foods containing them