Cladodes of Opuntia ficus-indica (L.) as source of bioactive compounds in dairy products

Abstract

Recently, the interest on improving livestock products' nutraceutical profiles by sustainable feeding systems has increased. In this context, the overall quality and, in particular, the nutraceutical profile of dairy products obtained by 16 lactating Cinisara cows fed integrated in dry season with Opuntia ficus-indica cladodes, were investigated. Two homogeneous groups of cows (milk yield: 6.3 ± 1.5 kg; body weight: 213 ± 55 kg) were in succession fed with 2 different diets (CON: pasture and wheat bran; OFI: pasture, wheat bran and cladodes), according to a 2 × 2 Latin square design. The bulk milk was used to make Caciotta cheeses, analyzed at 0, 15 and 30 storage days. Milk and cheeses samples were analyzed for chemical, physical and microbiological traits. On the final products, the nutraceutical and sensorial profiles, together with the antioxidant's capacity were also determined. On milk, only the urea content in individual samples was reduced in OFI. Considering the cheeses, the integration with cladodes did not influence the starter cultures development acted with 2 strains of S. thermophilus, but caused a higher content of polyphenols and a consequent greater antioxidant capacity, together with a change in the fatty acids profile. In particular, the caprylic, capric, lauric, myristic, and palmitic fatty acids were higher, as well as the petroselinic, vaccenic, rumenic, and α-linolenic fatty acids. Differently, the oleic and the γ-linolenic fatty acids were lower. The cheeses of OFI showed better overall acceptability, and a higher yellow color, odor intensities, and butter flavor. The multivariate analysis well distinguished the cheeses belonging to the 2 groups. Further investigations should be conducted to formulate well balanced diets including cladodes for Cinisara lactating cows, but also to determine the content of other important bioactive compounds in fresh and in treated cladodes, as well as their effects on animals' welfare and their productions.