Grape pomace journey from by-product to superfood

In a recent article published in a magazine food, researchers conducted a comprehensive review to synthesize research advances on the bioactive properties, health and nutritional benefits, and food system applications of grape pomace (GP), a wine by-product. Their conclusions have important applications for the sustainable development of the wine industry and the reduction of winery waste.

Winemaking is one of the world’s largest agricultural industries, generating large amounts of by-products and waste, of which GP is a significant part, accounting for almost a quarter of the weight of processed grapes. equivalent. Scientists believe that compounds in GP have antitumor, antioxidant, antibacterial, and antiaging properties and could be used to develop new foods and reduce waste from the wine industry. Masu.

Food waste not only causes inefficiencies and economic costs in supply chains, but also has serious environmental impacts. Under the Sustainable Development Goals, international organizations aim to reduce food waste and promote a more sustainable and efficient circular economy.

Research: Grape pomace – advances in its biological activity, health benefits, and food applications. Image credit: Piotr Velixar / Shutterstock

GP contains beneficial bioactive compounds

Based on the number of aromatic rings in its structure, GP contains three types of polyphenols: phenolic acids such as hydroxybenzoic acid, flavonoids such as anthoxanthins and anthocyanins, and nonflavonoids such as tannins and stilbenes.

By using environmentally friendly and naturally derived solvents such as ethanol, glycerol, and water and optimizing traditional extraction techniques, it has become easier to extract bioactive polyphenols from GP. Fiber, grapeseed oil and polyphenol extracts can be used in the food and cosmetic industries.

GP and other by-products are sometimes added to industrial formulations. Adding grape flour to foods promotes antioxidant activity and improves survival of probiotics in concentrated yogurt. Beyond nutrition, polyphenols also have beauty uses such as protecting against UV damage.

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These polyphenols have demonstrated health benefits

GP polyphenols appear to have anti-cancer properties, and several studies have shown that extracts were successful in slowing the growth of human breast and lung cancer, melanoma, colon cancer, and metastatic melanoma in mice. We know that However, further studies are needed in in vivo systems.

These bioactive compounds also have cardioprotective effects through improved vasorelaxation and altered lipid profiles. This appears to be mediated by antiplatelet activity, which does not differ between grape varieties but is influenced by the choice of extraction solvent. Oligomeric and monomeric flavan-3-ols are particularly effective in platelet aggregation.

Quercetin-3-O-glucuronide, catechin, and peonidin-3-O-acetylglucoside have been successful in inhibiting the action of digestive enzymes that cause the breakdown of carbohydrates, which has implications for the management of diabetes. . However, due to the multifactorial nature of diabetes, further research is needed into these applications.

The antihyperlipidemic properties of GP have also been evaluated using in vivo models, suggesting that GP supplementation may improve plasma lipid profiles and reduce total blood triglycerides in hamsters and rats. It has been. These benefits are thought to occur because polyphenolic compounds increase fatty acid metabolism, inhibit plasma secretion, decrease intestinal dietary fat absorption, and decrease apolipoprotein B secretion while increasing beta-oxidation. Masu.

Application in the food industry

Studies have shown that GP supplementation promotes antioxidant activity, and cakes supplemented with GP powder contain more lipids, anthocyanins, ash, dietary fiber, and polyphenols than flour cakes. Similar effects have been observed with GP-fortified bread, tea, and milk chocolate.

Introducing GP into common foods can extend shelf life. It can also inhibit the activity of harmful bacteria such as: Escherichia coli, Bacillus cereus, Staphylococcus aureus, Salmonella typhimuriumand candida albicans while promoting the probiotic activity of beneficial bacteria such as Bifidobacterium animalis and Lactobacillus acidophilus.

Another application for GP is in the production of baked goods and beverages, where it has been found to enhance sensory properties while increasing nutritional value. Characteristics of GP-fortified foods include a purple color, increased acidity, and decreased sweetness. Products tested for GP include bread, chocolate and meat products.

However, the amount of GP and type of product must be considered to ensure palatability, optimal taste and texture. For example, consumers may find the addition of a little GP more visually appealing.

conclusion

The promotion of GP has wide applications in the food and cosmetic industries and impacts food sustainability. GP polyphenols can be used to treat hypertension, diabetes, cancer, aging, neurodegenerative diseases, obesity, and can also be used to develop novel food and cosmetic products.

However, significant advances have been confined to a few countries, such as the United States and China, as evidenced by patents granted for bioactive foods, animal feed, and new extraction and preparation methods. Further research is needed in the field of GP-fortified foods with pilot-scale studies and economic evaluation to assess commercial feasibility.