The “Universidad Nacional de Cuyo”, in Mendoza, has been carrying out different studies. One of the last ones stood out for researching the use of waste in the pharmaceutical industry.
Andrea Antoniolli, a researcher at the Faculty of Agricultural Sciences, explained that in wineries, after the winemaking process there are different wastes left: liquids (effluent), organic solids (pomace, lees, stems), and other solids (derived from packaging, and others). The ones reused are those included in the second type. Pomace is derived from pressing and consists mainly of seeds and skins. Lees are sediments found in the wine, which are decanted by “racking” to be separated from the liquid. And stem is the woody part of the grape cluster coming from the destemming process.
“In all of them, an extraction of bioactive compounds, polyphenols, is made by means of methods that are not harmful to health. For example, if an extraction solvent is used, it must not leave toxic wastes”, explained Antoniolli. Those polyphenols have antioxidant properties and are used mainly in pharmaceutical and cosmetic products, although they are also utilized by food industry and even as fungicide.
The expert said that today lees must be taken to the distillery where tartaric acid and alcohol are extracted. As regards pomace, it is also sent to distilleries to obtain from it alcohol and by-products. “The used-up pomace is utilized as a fertilizer to improve soil”, she added. The use of stems is less defined: they usually are burnt, scattered over vineyard alleys or used in compost production (organic fertilizers).
“Due to the recent discovery of grape moth attack (Lobesia botrana), SENASA (Spanish acronym: National Animal Health and Agri-food Quality Services) has forbidden wineries to take pomace or stems out, unless they are sent to distilleries (placed within the area) for industrial processing”, explained Antoniolli. Without this restriction, wine wastes would be also used to control plagues and preserving of food. “Phenolic compounds are also a rich source of biocides and preservatives. Particularly, several studies have shown the efficiency of some kinds of phenolic compounds like antimicrobial and antioxidant ones”, added the researcher.
Currently, Antoniolli and a team headed by Dr. Rubén Bottini are developing a project to extract polyphenols from this type of waste, analyze them and identify the different chemical species. Then, they will study the effects of both crude extracts and main components on the anti-platelet activity in human blood and in culture of cells. The aim is to discover the healthy benefits of wine wastes.