Valorization of the by-products resulting from the manufacture of wine as natural antioxidants for the recipes of laying hens enriched in polyunsaturated fatty acids

Nowadays, when the interest for a healthier diet, using natural products, is growing, the presence and role of the chicken egg in the daily basket represents a challenge both for feed producers and for chicken egg producers. The nutritional value of the conventional egg has not been modified for a long time. But currently there is considerable concern to enrich the egg in certain nutrients beneficial for human health. Omega 3 polyunsaturated fatty acids (omega-3 PUFA) are such nutrients. These fatty acids are essential for the normal growth and development of the human body and can also play an important role in the prevention and treatment of cardiovascular diseases, hypertension, diabetes, arthritis, cancer, etc. The egg contains, in the yolk, omega-3 PUFA acids but not in a sufficient amount to ensure the daily requirement. Fortunately, with the help of feed recipes that include raw materials rich in PUFA omega-3 acids, their concentration in the egg yolk can be raised. If the combined feeds enriched in omega-3 PUFA acids do not contain effective antioxidants, peroxidation reactions occur, the first consequence of which is the rancidity (degradation) of the fat in these feeds. Degradation of fats in fodder for laying hens has of course also an effect on egg quality. The addition of antioxidants to the birds’ rations raises three major questions from a practical, technological and legal point of view: „for what?” „, „in what form? „, „how much?”. Currently, the most widely used antioxidants in poultry feed are of a synthetic nature: ethoxyquin (1, 2-dihydro-6-ethoxy-2,2,4-trimethylquinoline), BHA (hydroxy anisole butylate), BHT (hydroxytoluene butylate), vitamin E, etc. There is also the option of replacing synthetic antioxidants in feed with vegetable antioxidants rich in different substances with antioxidant capacity. The by-products obtained from the wine processing technology are among the natural antioxidants that have antioxidant properties because they have a very high level of polyphenols and citric acid. Several studies show that both the pomace obtained from the fermentation of grapes and the extracts from grape seeds have a strong antioxidant capacity. Considering the large volume of by-products obtained from wine processing in Europe and the significant environmental risk represented by this processed waste, we consider that it is an effective solution to use them in the fodder intended for birds and animals. In this context, the international consortium was established which implements a project whose objective is to capitalize on the by-products resulting from the manufacture of wine as natural antioxidants for the recipes of laying hens enriched in omega-3 PUFA acids.