In this article, we will see how to harness the properties of grapes for your beauty and well-being while directly contributing to environmental well-being.
Winemaking produces large quantities of waste every year. Today, it is urgent to address this waste in a sustainable way, in the context of a zero-waste circular economy.
What happens to the by-products? Most grape growers send the pomace to the distillery for grappa production, while the residues such as stems, lees, and wastewater are usually disposed of as waste (source: ENEA research, 2018).
However, today's challenges require finding the best way to recover winemaking waste, turning it into high added-value products (upcycling versus recycling).
A Few Numbers
Grapes are one of the most widely cultivated crops in the world, with about 80% of the total harvest dedicated to wine production. Global wine production in 2022 reached 258 million hectoliters, with approximately 160 million hectoliters produced in Europe, while Italian production stood at around 47,000 hectoliters.
On average, for every hectoliter of wine produced, 20 kg of pomace, 3.85 kg of stems, and over 6.36 kg of lees and clarification solids are generated. The production of stems and pomace ranges from 20 to 35% of the processed grapes, with smaller-sized companies producing the larger quantities.
Pomace: A Problem for Wineries
The disposal costs for winemaking residues are high because the spreadable quantities of pomace are subject to limitations (they risk increasing soil salinity and heavy metal content due to high nitrogen levels - according to the Nitrate Directive, which should not exceed 50 kg/ha for phosphorus). The preparation of compost is hindered by the polyphenols present in the pomace, which, being antiseptic, inhibit the microorganisms involved in the composting process, resulting in unsuitable products.
The industry produces huge quantities of solid residues, which are costly to dispose of. These include unripe grapes, leaves, pomace, grape seeds, stems, lees, and cellar wastewater. For the winemaking industry alone, some estimates indicate an annual availability of over 7 million quintals of unused pomace, which accounts for 3/4 of its volumes.
Dealing with their disposal innovatively and, more importantly, recovering and utilizing them is necessary. We must address their environmental impact.
Wine By-Products Become Opportunities
Research shows that pomace is rich in antioxidant properties, even after grappa production when it is generally disposed of (Effect of the distillation process on polyphenols content of grape pomace, Miluska Cisneros‐Yupanqui, Corrado Rizzi, Dasha Mihaylova, Anna Lante, 2021).
Wine by-products also contain many bioactive molecules that can be used in the fields of nutraceuticals (studying foods that are beneficial to health) and cosmetics.
With this goal in mind, Grapey was born to reuse winemaking waste, giving them new life by creating highly specific and effective green cosmetics.
"Green Cosmetic Chemistry" involves creating cosmetics that respect the environment and biodiversity through the study, design, and development of new sustainable ingredients, formulas, and processes, reducing energy consumption and using raw materials from renewable natural resources, ideally locally sourced. Moreover, if these ingredients are by-products, such as waste from the agri-food industry, the environmental benefit is greater.
By transforming by-products from waste into valuable resources (renewable resources), this approach aligns with a circular economy. This allows the recovery of polyphenols, which have interesting cosmeceutical and nutraceutical properties.
Wine By-Products Become Sources of Active Ingredients for the Skin
Wine by-products are rich in recoverable bioactive molecules. Among these are polyunsaturated fatty acids (PUFAs), pigments, proteins, phenolic compounds, and vitamins.
The polyphenolic compounds in the lees determine the color, intensity, and organoleptic properties of the wine. During winemaking, biochemical processes in the lees activate phenols, turning them into high-value polyphenolic compounds (including gallic acid, ellagic acid, catechin, caffeic acid, resveratrol). Polyphenols are rich in skin care properties.
In the production of high-quality wine, unripe grapes are thinned directly in the vineyard to ensure a higher sugar content in the remaining clusters.
Discarded unripe grapes can be a source of highly effective antioxidant phyto-complexes. They contain a high amount of extremely vital cells that can be used to obtain stem cells and thus produce G-CELL, an extremely effective antioxidant active ingredient that can combat free radicals. Its application in cosmetic formulations is potent because it significantly increases the skin's antioxidant capacity, providing effective protection against free radicals.
Grape seeds are what remains at the end of grape pressing: skins and grape seeds.
The skin protects the grape while it grows on the vine, providing an effective shield against UV exposure, attacks by pathogens, environmental pollution, and adverse weather conditions. The thousands of molecules that the grape can synthesize and accumulate in the skin are the secret to these defenses.
Grape seeds at the end of the winemaking process, even after grappa production, contain significant amounts of bioactive substances useful for human health: fibers, tannins, and other polyphenolic substances, along with a good percentage of fats, sugars, and tartaric acid salts.
In fact, polyphenols are not uniformly distributed among the different parts of the grape: the pulp is almost devoid of them, with the highest concentrations found in the skin and seeds.
Particularly interesting molecules include:
- Rutin: a flavonoid glycoside with antioxidant and radical-scavenging properties, which appears to play an important role in inhibiting certain types of tumors.
- Quercetin: one of the main flavonoids with anti-inflammatory and anti-cancer properties.
- Resveratrol: one of the phytoalexins naturally produced by the vine for defense against pathogens such as bacteria or fungi, with antioxidant, anti-inflammatory, vasodilating properties, and improvement of skin microcirculation and skin due to increased collagen synthesis. Resveratrol has gained significant attention for its potential anti-cancer properties, especially as a chemopreventive agent.
Properties of Grape Pomace
As we've seen, in the wine industry, grape pomace is costly to dispose of but is still rich in free and complex phenols and polyphenols. While, on one hand, they are considered pollutants because they increase the chemical and biochemical oxygen demand, with detrimental effects on the flora and fauna of discharge areas, on the other hand, they are among the main contributors to health benefits due to their antioxidant activity.
One of the most interesting applications of grape pomace is in the cosmetic industry. Grape pomace can become a fundamental component of creams with anti-aging, purifying, hydrating, and toning properties for the face and body. Being rich in polyphenols, it exerts an anti-inflammatory action and combats free radicals, actively working against skin aging.
For this reason, we at Grapey have created a specific cream for women, derived from active grape ingredients: an effective anti-aging, antioxidant, and hydrating product. Grapey Anti-age is recommended for those who want to combat the signs of aging, from expression lines to wrinkles, and deeply hydrate and revitalize their skin with a natural product.
Grape seeds are the grape cluster's woody structure. They are often reclaimed in feed production and soil care.
However, they are interesting as a source of dietary fiber and antioxidants. The polyphenolic content primarily consists of flavan-3-ols, monomeric and oligomeric flavonols belonging to the flavonoid class, and hydroxycinnamic and stilbene acids belonging to the non-flavonoid class.
Grapevine leaves can be considered on par with stems and are rich in organic acids, phenolic acids, flavonols, tannins, procyanidins, anthocyanins, lipids, enzymes, vitamins, carotenoids, terpenes, and reducing or non-reducing sugars.
Lees are the residue deposited after wine fermentation, primarily made up of spent yeasts, tartrates, and impurities derived from grapes. Lees are traditionally a fundamental raw material for the production of ethanol and tartaric acid. The latter has many applications in the food industry as an excellent stabilizer, replacing citric acid, with antioxidant, anti-inflammatory, anti-tumor, and cardiovascular disease prevention capabilities.
Some acids, such as gallic acid, along with other phenolic extracts, appear to have the ability to counteract bacterial adhesion to tooth enamel, generating interest in the production of functional foods, such as chewing gum.
Naturally combat external aggressions and rediscover your natural beauty and firmness.