Characterization of artisanal saffron ricotta cheese produced in Sicily: Physicochemical, microbiological, sensory, and antioxidant characteristics.

The present study aims to characterize the artisanal saffron ricotta cheese produced from the whey of Piacentinu Ennese protected designation of origin (PDO) cheesemaking, including via technological parameters detected during the production process and by assessment of the main physicochemical, microbial, sensory, and antioxidant characteristics. A survey on the manufacture process of saffron and control ricotta cheese was conducted on 3 farms, located in the production area of the Piacentinu Ennese PDO cheese. pH and temperature followed a specific behavior, characterized by an inverse trend where pH decreased and temperature increased, playing an important role in the production process. All the analytical parameters were affected by the presence of saffron, also showing high between-farm variability, with significantly higher total solids and fat contents in saffron ricotta cheese compared with the control cheese (28.68% vs. 23.86%, and 19.83% vs. 14.22%, respectively). Microbial analysis showed significantly lower values in saffron compared with control ricotta cheese, for coliforms (1.51 vs. 1.91 log10 cfu/g, respectively), yeasts (1.55 vs. 2.06 log10 cfu/g, respectively), and molds (1.03 vs. 1.30 log10 cfu/g, respectively), denoting potential reduction of microbial growth asserted by saffron. Escherichia coli concentration (1.26 log10 cfu/g) in saffron ricotta cheese was in accordance with EU Regulation 2073/2005 and then safe for consumption. The presence of saffron influenced all sensory attributes, particularly color and aroma. Interestingly, high total antioxidant activity was found in saffron ricotta cheese (372 µC) compared with the control cheese. Thus, this artisanal dairy production could be considered a suitable option for functional foods with antimicrobial properties, due to the presence of saffron, which may contribute to extend the shelf life of the product. Further studies need to focus on the bioactive compounds that affect the antioxidant proprieties, characterization of the microbiota of saffron ricotta cheese, and evaluation of consumers' acceptance and perception as well as market demand.

Effect of Dietary Hazelnut Peels on the Contents of Fatty Acids, Cholesterol, Tocopherols, and on the Shelf-Life of Ripened Ewe Cheese.

Hazelnut peel (HNP), a by-product from the chocolate industry, is considered to be a suitable ingredient to be included in the diet of ruminants. This study aimed to evaluate the effect of feeding dairy ewes with a diet containing HNP on ripened cheese quality, including fatty acid (FA) profile, cholesterol, and tocopherol content, as well as stability during storage under commercial conditions. In total, 10 experimental cheeses were produced with bulk milk obtained from ewes fed a commercial concentrate (C group; n = 5) or a concentrate containing 36% HNP in dry matter (HNP group; n = 5). After 40 days of aging, each cheese was sub-sampled into three slices: one was analyzed immediately (C0 and HNP0), and the other two were refrigerated and analyzed after seven days (C7 and HNP7) and 14 days (C14 and HNP14), respectively. Compared to C, HNP cheese had more than twice as many tocopherols and mono-unsaturated FA and respectively 38% and 24% less of cholesterol and saturated FA. Tocopherols and cholesterol levels remained rather stable up to 14 days of storage regardless of the experimental group, suggesting no cholesterol oxidation. Therefore, the inclusion of HNP in ewe diets could be a valid resource to produce cheese with a healthier lipid profile and higher tocopherols content.

Hazelnut as Ingredient in Dairy Sheep Diet: Effect on Sensory and Volatile Profile of Cheese.

The opportunity of replacing expensive feedstuffs with agro-industrial by-products in the diet of food producing animals is raising increasing interest while addressing global concern for the scarcity of natural resources and environmental impact of livestock farming. Hazelnut peels, rich in fiber and vitamins and characterized by a high concentration of fats, is considered a suitable ingredient to be included in the diet of ruminants. The aim of this research was to assess the effect of dietary hazelnut peels on the chemical and sensory properties of sheep cheese during refrigerated storage. To this purpose, 20 Comisana lactating ewes were randomly assigned to two experimental groups, control (C) and hazelnut peels (HP), balanced for parity, milk yield and body weight. Bulk milk collected from the 2 groups was used to produce 5 Pecorino cheeses for each group. After 40 d of aging, each cheese of each experimental group was divided into 3 pieces: 1 piece was sampled for analyses (C0, HP0) and 2 were wrapped in PVC film, simulating the condition of pre-wrapped products, and analyzed after 7 (C7, HP7) and 14 days of storage (C14, HP14) at 8°C with 80% moisture. The cheeses were analyzed for chemical and fatty acid composition, sensory analysis, odor active compounds and SmartNose. As expected, HP cheeses presented a higher lipid content compared to C, a lower content in SFA and PUFA, and a greater content in MUFA. A triangle test revealed a clear distinction between the 2 groups (α = 0.01) The sensory profile showed a significant effect on holes (P < 0.05) and a marginal production of off-flavors linked to spicy and acid attributes for HP cheeses The volatile profile of C and HP cheese samples showed a good similarity, partially explained by the short ripening time and the absence of 2-nonanone in HP7, suggesting a higher antioxidant protection grade of this cheese compared to the others. These results were confirmed by Smart Nose analysis. Further studies on vitamin content should be conducted in order to investigate the interactions between the presence of antioxidant volatile compounds and the oxidative stability of ewe cheese.

PGC-1-related coactivator: immediate early expression and characterization of a CREB/NRF-1 binding domain associated with cytochrome c promoter occupancy and respiratory growth.

PGC-1-related coactivator (PRC) was initially characterized as a transcriptional coactivator that shares structural and functional features with PGC-1alpha. Both coactivators interact with nuclear respiratory factor 1 (NRF-1) and activate NRF-1 target genes required for respiratory chain expression. Here, we establish that PRC belongs to the class of immediate early genes that are rapidly induced in the transition from quiescence to proliferative growth. As observed for other members of this class, the rapid serum induction of PRC mRNA does not require de novo protein synthesis and inhibition of protein synthesis stabilizes PRC mRNA, leading to its superinduction. Previous work indicated that PRC activation of cytochrome c expression occurs through cis-acting elements that bind both NRF-1 and CREB. Here, we demonstrate that, like NRF-1, CREB binds PRC in vitro and exists in a complex with PRC in cell extracts. Both CREB and NRF-1 bind the same sites on PRC, and the interaction with CREB requires the CREB b-Zip DNA binding domain. Moreover, a CREB/NRF-1 interaction domain on PRC is required for its trans activation of the cytochrome c promoter and a PRC subfragment containing this domain inhibits respiratory growth on galactose when expressed in trans from a lentivirus vector. Finally, PRC associates with the cytochrome c promoter in vivo and its occupancy of the promoter is markedly elevated in response to serum induction of quiescent fibroblasts. The results establish that PRC is an immediate early gene product that can target key transcription factors as an early event in the program of cellular proliferation.