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Zinc is essential for animals, playing a vital role in enzyme systems and various biochemical reactions. It is crucial to ensure a sufficient intake of zinc through the diet to maintain efficient homeostasis. Only few studies on zinc effect in cow lactating diet evaluated the effects on milk and cheese quality, with conflicting findings. 24 cows of the Friesian breed were divided into two groups (CTR: control and TRT: treated group). Cows were selected for age, body weight, parity and phase of lactations (mid lactation, 140-160 days). CTR diet contained 38 mg/kg of Zn and TRT diet was supplied with 120 mg/kg of complete feed for 60 days. The objective of current investigation was to evaluate the impact of a dietary Zinc Oxide (ZnO) integration of lactating Friesian cows on chemical composition, zinc content, fatty acid and proteic profile, ammine content, pH, aw, texture, and sensory profile of cheese and to improve the chemical-nutritional quality of milk and cheese. The results showed that ZnO supplementation reduced mesophilic aerobic bacteria and Presumptive Pseudomonas spp. growth, proteolysis, biogenic amines content, lipid oxidation, odour intensity and sour and increased hardness, gumminess, chewiness, elasticity of cheese. Biogenic amines are considered an important aspect of food safety. ZnO integration in cow diet could represent a promising strategy for improving the quality, the safety and shelf-life of caciotta cheese.

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The research studied the effects of dietary supplementation with Camelina sativa fresh forage on the chemical and fatty acid composition of milk and Caciotta cheese, and its sensory properties. Twenty Ionica goats were randomly assigned to the following two groups (n = 10): the control received a traditional forage mixture (Avena sativa, 70%; Vicia sativa, 20%; Trifolium spp., 10%), while the experimental group was given Camelina sativa fresh forage (CAM). All of the dams grazed on pasture and received a commercial feed (500 g/head/day) at housing. The milk from the CAM group showed a higher (p < 0.05) content of dry matter, fat, lactose and concentrations of C6:0, C11:0, C14:0, C18:2 n-6, CLA and PUFA, while lower (p < 0.05) amounts of C12:0, C18:0 and saturated long chain FA (SLCFA). The Caciotta cheese from the CAM group showed a greater (p < 0.05) content of n-6 FA and n-6/n-3 ratio, although close to four, thus resulting adequate under the nutritional point of view. The overall liking, odour, taste, hardness, solubility and "goaty" flavour were better (p < 0.05) in the CAM cheeses. Further investigation would be advisable in order to evaluate the effect of feeding Camelina forage obtained from different phenological stages, and the application of ensiling techniques.

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Caciotta is the name used to define a type of Italian semi-hard cheese Caciotta-type cheese. Due to the short ripening time, pasteurization is necessary to eliminate the potential pathogenic bacteria, which may be present in raw milk, causing also the reduction of ripened cheese flavor. The purpose of this research was to evaluate the effect of a selected wild Lactobacillus paracasei strain experimentally used as adjunct culture to enhance the flavour formation in a short-ripened caciotta-type cheese. An integrated polyphasic approach was used to compare the experimental and control Caciotta produced in a company located in Emilia Romagna region (Italy). It was demonstrated how the L. paracasei 4341 was able to develop in curd and cheese interacting with the acidifying commercial starter. The main acidifying starter species, were differently affected by the presence of the adjunct culture. Streptococcus thermophilus shown comparable behavior in all cheese-making step of control and experimental Caciotta, while Lactobacillus delbrueckii subsp bulgaricus, growth was slowed down by the presence of the adjunct culture during the whole ripening time. The higher amount of volatile compounds and organic acids due to the adjunct L. paracasei 4341 lead to a clear differentiation of the experimental Caciotta respect to the control, in terms of aromatic profile, color, texture and sensorial perception.

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This study aimed at establishing the effects of attenuated starters and surface bacteria on various features of caciotta cheese. The cheese undergoes a ripening period during which the house microbiota contaminates the surface. Conventional cheese (the control cheese [CC]) is made using only primary starters. Primary starters and attenuated (i.e., unable to grow and synthesize lactic acid) Lactococcus lactis (Lc. lactis) subsp. lactis were used to produce caciotta cheese without (ATT cheese) or with an inoculum of surface bacteria: (i) Leuconostoc lactis (Le. lactis) (LL cheese), (ii) Vibrio casei (VC cheese), (iii) Staphylococcus equorum (SE cheese), (iv) Brochothrix thermosphacta (BX cheese), and (v) a mixture of all four (MIX cheese). Attenuated Lc. lactis increased microbial diversity during cheese ripening. At the core, attenuated starter mainly increased indigenous lactococci and Lactobacillus delbrueckii group bacteria. At the surface, the main effect was on Macrococcus caseolyticus Autochthonous Le. lactis strains took advantage of the attenuated starter, becoming dominant. Adjunct Le. lactis positively affected Lactobacillus sakei group bacteria on the LL cheese surface. Adjunct V. casei, S. equorum, and B. thermosphacta did not become dominant. Surfaces of VC, SE, and BX cheeses mainly harbored Staphylococcus succinus Peptidase activities were higher in cheeses made with attenuated starter than in CC, which had the lowest concentration of free amino acids. Based on the enzymatic activities of adjunct Le. lactis, LL and MIX cheeses exhibited the highest glutamate dehydrogenase, cystathionine-γ-lyase, and esterase activities. As shown by multivariate statistical analyses, LL and MIX cheeses showed the highest similarity for microbiological and biochemical features. LL and MIX cheeses received the highest scores for overall sensory acceptability.IMPORTANCE This study provides in-depth knowledge of the effects of attenuated starters and surface bacterial strains on the microbiota and related metabolic activities during cheese ripening. The use of attenuated Lc. lactis strongly impacted the microbiota assembly of caciotta cheese. This led to improved biochemical and sensory features compared to conventional cheese. Among surface bacterial strains, Le. lactis played a key role in the metabolic activities involved in cheese ripening. This resulted in an improvement of the sensory quality of caciotta cheese. The use of attenuated lactic acid bacteria and the surface adjunct Le. lactis could be a useful biotechnology to improve the flavor formation of caciotta cheese.

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HIGHLIGHTS: The aflatoxin M1 content in milk was not related to the enrichment factor. The enrichment factor in 45-day ripened semihard cheese was defined. The enrichment factor in cheese is affected by cheese yield.

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The aim of the present work was to explore the chemical-sensorial characteristics and aromatic profile of caciotta cheese obtained from Friesian cows fed a diet enriched with grape pomace obtained from red grape (Vitis vinifera L.). Dietary enrichment with grape pomace influenced the production of caciotta cheeses in interesting ways from a compositional point of view, as cheese samples were rich in polyphenols, giving a high antioxidant potential. From a biochemical standpoint, we noted a slight decrease of proteolysis during ripening, whereas, according to the analysis of volatile compounds, lipolysis was the most relevant phenomenon in samples. The presence of bioactive compounds also modified the fatty acid profile of milk and cheese, leading to an increase in concentration of linoleic, vaccenic, and rumenic acids. No significant variations were found in the sensory profile. These results showed the potential of dietary grape pomace intake to influence the chemical-nutritional and nutraceutical properties of cow milk and cheeses, whose introduction to the market could be attractive to consumers, providing interesting implications for the dairy industry. Finally, our results identified of a valid use of an agro-industrial by-product, grape pomace, whose disposal generally presents economic and environmental problems.

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