This review focused on the historical, technological, and analytical characteristics of ricotta cheese available in the literature. Ricotta cheese is a typical dairy product that originated from Italy, used in the preparation of several traditional dishes, both sweet and salted. The available studies pertaining to ricotta cheese revealed a considerable biodiversity in the production with a large number of varieties produced, whose production varies according to the local uses and customs. The review shows the main chemical and microbial characteristics of the product and also the several parameters that affect the mechanism of the production process and the final characteristics of the product, including the raw materials, the processing methods, the season, the animals' diet, the animals' species, and breeds. Ricotta production can be artisanal or industrial, with differences in the making process. New trends in ricotta cheese production have been developed, with particular attention to the functional effect on human health and the novel technologies applied to extend the shelf-life of the products. Currently, it is not easy to find these new developments in the market, probably related to the cost of production, which is not always bearable by the farms. However, despite the large classification reported and the great interest by the cheese industry, just a few numbers of studies were found for artisanal ricotta productions, which still need to be characterized and studied.

In this study, PDO Provola dei Nebrodi cheese was deeply characterized for its bacterial community and chemical composition. Four dairy factories (A-D) were monitored from milk to ripened cheese. Wooden vat biofilms were dominated by thermophilic rod LAB (4.6-6.5 log CFU/cm²). Bulk milk showed consistent levels of total mesophilic microorganisms (TMM) (5.0-6.0 log CFU/mL) and, after curdling, a general increase was recorded. The identification of the dominant LAB in wooden vat biofilms and ripened cheeses showed that the majority of wooden vat LAB were lactococci and Streptococcus thermophilus, while cheese LAB mainly belonged to Lacticaseibacillus paracasei and Enterococcus. Illumina sequencing identified 22 taxonomic groups; streptococci, lactococci, lactobacilli and other LAB constituted the majority of the total relative abundance % of the wooden vat (69.01-97.58 %) and cheese (81.57-99.87 %) bacterial communities. Regarding chemical composition, the effect of dairy factories was significant only for protein content. Inside cheese color was lighter and yellower than surface. Differences in fatty acids regarded only myristic acid and total amount of monounsaturated fatty acids. The sensory evaluation indicated some differences among cheeses produced in the four dairies regarding color, homogeneity of structure, overall intensity, salty, spicy, and hardness. The integrated approach applied in this study showed that PDO Provola dei Nebrodi cheese characteristics are quite stable among the dairy factories analyzed and this has to be unavoidably imputed to the application of the same cheese making protocol among different dairies.

The present study aims to characterize the artisanal saffron ricotta cheese, produced from the whey of Piacentinu Ennese PDO cheesemaking, including the detection of technological parameters detected during the production process, and the assessment of the main physical-chemical, 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 making process. All the analytical parameters were affected by the saffron presence, showing also high between-farm variability, with significantly higher total solid and fat content in saffron ricotta cheese compared with control one (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 the potential reduction of the microbial growth asserted by saffron. E. coli concentration (1.26 log₁₀ cfu/g) in saffron ricotta cheese was in accordance with the REG (EU) 2073/2005 and then safe for consumption. Saffron presence influenced all the sensory attributes, particularly the color and the aroma. Interesting high total antioxidant activity was found in saffron ricotta cheese (372 e-BQC) compared with control one. Thus, this artisanal dairy production could be considered a suitable option of functional foods with antimicrobial propriety, due to the saffron presence, 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, the characterization of the microbiota of the saffron ricotta cheese, and the evaluation of consumers' acceptance and perception as well as market demand.

The biofilms of the wooden tables used for the acidification of the curd were investigated for PDO Provola dei Nebrodi cheese, a traditional stretched cheese made in eastern Sicily (southern Italy) from raw cows’ milk. To this purpose the wooden tables of four dairy facilities were analysed for their microbiota by scanning electron microscopy (SEM) analysis and a combined culture-independent and -dependent microbiological approach. SEM inspection showed an almost continuous biofilm formation. MiSeq Illumina analysis identified 8 phyla, 16 classes, 25 orders, 47 families and 50 genera. Corynebacterium, Bifidobacterium and lactic acid bacteria (LAB) were detected in all samples. In particular, the LAB genera detected on all wooden tables were Lactobacillus, Streptococcus and Lactococcus. LAB dominated the surfaces of all wooden tables with levels higher than 7.0 Log CFU/cm². In particular, the LAB found at the highest levels were mesophilic cocci. Coagulase positive staphylococci, Salmonella spp., Listeria monocytogenes and Shiga-toxigenic Escherichia coli were never detected. Twenty-seven dominating LAB strains were identified within the genera Enterococcus, Lactobacillus, Lacticaseibacillus, Lactiplantibacillus, Levilactobacillus, Lactococcus, Leuconostoc, Pediococcus and Streptococcus. This work showed that the wooden table used during the production of PDO Provola dei Nebrodi cheese is a safe system and a microbiologically active tool.

The aim of this study was to investigate the effect of partially replacing maize with hazelnut skin and linseed, alone or in combination, on the oxidative stability of lamb. Forty lambs were randomly assigned to 4 treatments and fed: a conventional cereal-based diet (C), or the same diet with 15 % of hazelnut skin (HS), or 8 % of extruded linseed (LS), or 7.5 % of hazelnut skin plus 4 % of linseed (H + L) as partial replacement of maize. After 60 days of feeding trial, lambs were slaughtered, and hydrophilic antioxidant capacity and fat-soluble vitamins content were evaluated in fresh meat. Colour stability, lipid and protein oxidation were assessed during 7 days of refrigerated storage. Dietary combination of hazelnut skin and linseed increased the content of tocopherols (P < 0.001) and of n-3 polyunsaturated fatty acids (PUFA n-3; P < 0.001), while reducing lipid oxidation (TBARS value) during 7 days of storage (P < 0.001). Feeding lamb with hazelnut skin and/or linseed did not affect meat hydrophilic antioxidant capacity, colour stability, nor the formation of hydroperoxides, thiols, or carbonyls (P > 0.05). These results suggest that vitamin E provided by hazelnut skin contributed to delay lipid oxidation in meat, despite the higher concentration of n-3 PUFA.

Ricotta cheese is an Italian dairy product obtained by heat-coagulation of the proteins in whey, resulting from cheese production. The homogenization method applied to collect ricotta cheese samples could affect the total solids (TS) contents of the products. The aim of this study was to determine the effects of 5 different homogenization methods of the samples collection applied for the accuracy in TS determination in ricotta cheese, including un-homogenized method (UNH), un-homogenized combined with the Ultra-Turrax (IKA-Werke GmbH & Co. KG) method (UNH-UTX), spoon-homogenized method (SPN), spoon-homogenized combined with Ultra-Turrax method (SPN-UTX), and Ultra-Turrax homogenized method (UTX). The repeatability and the standard deviation of repeatability are indicators of agreement between repeated measures for TS contents. Results reported that UNH ricotta cheese samples showed large variation in TS content with values ranging from 18.31% to 25.85% and a standard deviation of repeatability higher than 1%; SPN samples showed repeatability values higher than 0.35% and standard deviation of repeatability ranged until 1.36%, suggesting large variability even in this case; the Ultra-Turrax homogenization reported repeatability values lower than 0.1% and standard deviation of repeatability lower than 0.05%, indicating that this method provides repeatable measurements that may reduce the sources of uncertainty in TS determination.