Circular bioeconomy for olive oil waste and by-product valorization: effect of dietary enriched olive cake inclusion in Modicana cows feeding management on cheese quality

The circular economy and bioeconomy can contribute to transitioning towards more sustainable production and consumption in the olive oil sector. During olive harvesting and subsequent oil production, large quantities of by-products are accumulated in a short time. Several studies have tested olive cake in animal feed to produce derived foods with improved nutritional profiles. Aim of study was to evaluate the effects of olive cake supplementation in the diet of Modicana dairy cows in terms of the quality of the Provola cheese obtained. A total of 24 multiparous Modicana dairy cows were randomly allocated, according to milk yield (MY), days in milking (DIM), and parity, to 1 of 2 dietary groups: the control group (CTR; MY: 12.2±3 kg/d; DIM: 127±17 d; parity: 3.3±1.5) was fed with a conventional diet, without any integration, whereas the treated group (OC; MY: 13.4±4 kg/d; DIM: 137±25 d; parity: 2.8±1.3) was fed with a conventional diet integrated 7% of dried and pitted olive cake. The chemical composition, fatty acid profile and polyphenol content was evaluated in Provola cheeses from CTR and OC groups. The total lipid content was 23% in CTR and 24% in OC samples. Compared with CTR, the fatty acid profile of OC Provola was characterized by lower content of C16:0 (31.07% for OC vs. 32.00% for CTR) and C14:0 (11.30% for OC vs. 12.10% for CTR) and greater content of C18:1 n-9 (22.40% for OC vs. 20.60% for CTR). In general, an increase in PUFAs as well as a decrease in SFAs was observed in OC Provola. These effects on the fatty acids profile of cheese are consistent with the findings of several authors regarding cheese produced by dairy ruminants fed with olive by-products. In addition, the content of total polyphenols in OC Provola was significantly higher than CTR (335±10.65 vs. 170±6.99mg/kg, respectively). To conclude, a Provola with functional characteristics would be gladly welcome and well appreciated by consumers. Therefore, the reuse of waste biomass could contribute to ensuring the wellness of people and the environment.