Influence of olive leaves feeding on chemical-nutritional quality of goat ricotta cheese

The industrial sector dedicated to the production of olive oil produces every year significant amounts of by-products, a part of which is represented by leaves deriving from pruning. These by-products represent an economic and sustainable source of bioactive compounds credited of positive benefits for human health. The aim of this study was to investigate the effects of dietary olive oil (OL) supplementation of Saanen goats on chemical-nutritional composition and volatile fraction of ricotta cheese. Twenty six Saanen goats were randomly divided into two equal groups: one fed with a conventional diet (CG) and one fed with a diet enriched with olive leaves (EG). After thirty days of trial, the milk collected from the two groups was used to made ricotta cheese. Dietary OL supplementation improved the oxidative stability of ricotta cheese during storage time and provided an increase of unsaturated fatty acid as vaccenic acid, CLA, and linolenic acid, and a decrease of ω-6/ω-3 ratio. EG ricotta cheeses were also characterized by a higher content of polyphenol compounds and higher antioxidant capacity compared to CG ricotta cheeses. Finally, also the volatile profile resulted affected by the diet with a significant decrease of ketones. The obtained results suggested a positive role of OL in the production of functional foods, credited of high health value.