51 Effect of grazing pasture on ricotta cheese quality traits.

Abstract Pasture-based dairy products are increasingly popular due to consumer interest in health, natural production, and animal welfare. Studies show that grazed herbage affects the fatty acid (FA) profile and color of dairy products, with higher β-carotene levels enhancing yellowness and providing health benefits. However, few research has examined these effects in ricotta cheese, obtained from whey a by-product of the cheese-making. This study assessed the impact of pasture availability on the FA profile, color, and β-carotene content of cow ricotta cheese. The trial covered two feeding periods: the dry season (DS), when cows were fed indoors, given a standard ratio composed of hay (60%) and concentrate (40%), and the pasture season (PS), when animals grazed on fresh forage (44%) with integration in the barn (56%). Ricotta cheese samples were collected in triplicate from five semi-extensive farms per season and analyzed for color, β-carotene, and FA composition. Data were statistically analyzed using a mixed model. The PS ricotta cheese had a significantly higher (P< 0.001) b* index than DS samples (9.64 vs. 6.52), indicating increased yellowness, directly correlating with higher β-carotene content (5.03 vs. 0.66 mg/kg). The PS samples also showed significantly higher (P< 0.001) total PUFA (5.02 vs. 4.13 g/100g FA) and MUFA (30.3 vs. 29.5 g/100g FA), while SFA was lower. Notably, α-linolenic acid and total n-3 FA were significantly higher in PS ricotta cheese (0.87 vs. 0.47 g/100g FA and 1.25 vs. 0.74 g/100g FA), reducing the n-6/n-3 FA ratio (3.10 vs. 4.74). The atherogenicity and thrombogenicity indexes were also significantly lower (P< 0.001) in PS samples compared to DS (2.34 vs. 2.58 and 2.57 vs. 2.99 respectively). These findings highlight the nutritional benefits of pasture feeding, resulting in a healthier ricotta cheese. Moreover, carotenoids and favorable FA profiles could serve as biomarkers for pasture-based ricotta cheese production. This work was supported by the National Recovery and Resilience Plan (NRRP), NextGenerationEU; Project code PE00000003, CUP E63C22002060006, Project title “ON Foods - Research and innovation network on food and nutrition Sustainability, Safety and Security – Working ON Foods”.