Pasta-filata cheeses

Compositional Differences of Greek Cheeses of Limited Production

Greece has a long tradition in cheesemaking, with 22 cheeses registered as protected designation of origin (PDO), 1 as protected geographical indication (PGI), and 1 applied for PGI. Several other cheeses are produced locally without any registration, which significantly contribute to the local economy. The present study investigated the composition (moisture, fat, salt, ash, and protein content), color parameters, and oxidative stability of cheeses that do not have a PDO/PGI certification, purchased from a Greek market. Milk and cheese types were correctly assigned for 62.8 and 82.1 % of samples, respectively, through discriminant analysis. The most important factors for milk type discrimination were L, a and b color attributes, salt, ash, fat-in-dry-matter, moisture-in-non-fat-substance, salt-in-moisture, and malondialdehyde contents, whereas a and b, and moisture, ash, fat, moisture-in-non-fat substance contents, and pH were the most influential characteristics for sample discrimination according to cheese type. A plausible explanation may be the differences in milk chemical composition between three animal species, namely cows, sheep, and goats and for the manufacture procedure and ripening. This is the very first report on the proximate analysis of these, largely ignored, chesses aiming to simulate interest for further study and production valorization.

Seasonal variations in the functional performance of industrial low-moisture part-skim mozzarella over a 1.5-year period

Seventy-five blocks of low-moisture part-skim mozzarella cheese were procured from an industrial cheese plant, and the relationships between the physicochemical and functional properties were evaluated during refrigerated storage. In total, cheeses were obtained from 1 cheese vat on 7 different production dates, at 2 to 4 monthly intervals, over a 1.5-yr period; all cheeses were made using a standard recipe. The cheeses were held at 4°C for 0, 1, 2, 4, 8, 16, or 32 d and assayed for composition, primary proteolysis, serum distribution, texture profile analysis, heat-induced changes in viscoelastic behavior, cheese extensibility, and melt characteristics. The results demonstrated a substantial increase in serum uptake by the calcium-phosphate para-casein matrix between 1 and 16 d of storage with a concomitant improvement in the functional performance of the cheese. Extending the storage time to 32 d resulted in further changes in the functional quality, concurrent with ongoing increases in protein hydration and primary proteolysis. Differences in the measured characteristics between the cheeses obtained on different sampling occasions were evident. Principal component analysis separated the cheeses based on their variance in functional performance, which was found to be correlated mainly with the calcium content of the cheese. The results indicate that the manufacturing process should be tightly controlled to minimize variation in calcium content and enhance the quality consistency of the cheese.

The Effect of Mixing Milk of Different Species on Chemical, Physicochemical, and Sensory Features of Cheeses: A Review

The yield and quality of cheese are associated with the composition, physicochemical, sensory, rheological, and microbiological properties of milk and with the technology applied to the milk before and/or during cheese processing. This review describes the most important research on cheeses obtained from processing mixtures of different milk species and discusses the effect of milk mixtures (i.e., species and mixture ratios) on composition, physicochemical, sensory, rheological, and microbiological properties of cheeses. More specifically, the present review paper will gather and focus only on studies that have provided a clear comparison between cheeses produced from a mixture of two milk species to cheeses produced from only one species.

Semi-Industrial Production of Kashkaval of Pindos Cheese Using Sheep or a Mixture of Sheep-Goat Milk and the Utilization of the Whey for Manufacturing Urda Cheese

Kashkaval of Pindos cheese was successfully produced using 100% sheep milk (KS) or with the addition of 10% goat milk (KG). Urda cheese was manufactured using 100% sheep (US) or 90% sheep–10% goat (UG) whey from the production of kashkaval of Pindos cheese. Both cheeses were made taking into account their traditional cheese-making methods. The cheeses were assessed for their chemical, microbiological and organoleptic characteristics. Generally, no significant differences were observed between KS and KG cheese and between US and UG cheese regarding their physicochemical, textural characteristics, soluble nitrogen fraction and total fatty acid content. The fat content of Urda cheese was low, in accordance with the demand of consumers for healthy products. KS cheeses showed higher total volatile compounds than KG cheeses at 60 and 90 days of ripening and storage as well as lower counts of thermophilic–mesophilic lactic acid bacteria. No differences were observed in the microbial counts between US and UG cheeses. Acetone, hexanal, 2 heptanone, ethanol and toluene were found in abundance in Urda cheeses. Both kashkaval of Pindos and Urda cheeses received high scores during the organoleptic evaluation. The obtained data may lead to the production of both cheeses with standard characteristics according to the traditional recipes and improve their recognition.

Bioactive amines in Mozzarella cheese from milk with varying somatic cell counts

The influence of somatic cells counts (SCC) in milk on bioactive amines in Mozzarella cheese was investigated. High SCC milk had lower lactose and higher pH compared to low and medium SCC. Low spermine levels were found in milk irrespective of SCC. The cheeses had similar characteristics, but the extension and depth of proteolysis increased with SCC. Cheese from all SCC categories contained spermine; whereas tyramine and tryptamine were only detected in cheese from high SCC milk. During 60-days refrigerated storage, significant positive effects were observed between SCC and proteolysis, storage time and pH and storage time and proteolysis. There was a significant positive effect of storage time on spermine and serotonin levels. Only cheese from high SCC milk showed significantly higher serotonin levels. Tyramine and tryptamine were found in cheese from high SCC milk.

Microbial ecology dynamics reveal a succession in the core microbiota involved in the ripening of pasta filata caciocavallo pugliese cheese

Pyrosequencing of the 16S rRNA targeting RNA, community-level physiological profiles made with Biolog EcoPlates, proteolysis, and volatile component (VOC) analyses were mainly used to characterize the manufacture and ripening of the pasta filata cheese Caciocavallo Pugliese. Plate counts revealed that cheese manufacture affected the microbial ecology. The results agreed with those from culture-independent approaches. As shown by urea-PAGE, reverse-phase high pressure liquid chromatography (RP-HPLC), and free-amino-acid (FAA) analyses, the extent of secondary proteolysis mainly increased after 30 to 45 days of ripening. VOCs and volatile free fatty acids (VFFA) were identified by a purge-and-trap method (PT) and solid-phase microextraction (SPME) coupled with gas chromatography-mass spectrometry (GC-MS), respectively. Except for aldehydes, the levels of most of VOCs and VFFA mainly increased from 30 to 45 days onwards. As shown through pyrosequencing analysis, raw cows' milk was contaminated by Firmicutes (53%), Proteobacteria (39%), Bacteroidetes (7.8%), Actinobacteria (0.06%), and Fusobacteria (0.03%), with heterogeneity at the genus level. The primary starter Streptococcus thermophilus dominated the curd population. Other genera occurred at low incidence or sporadically. The microbial dynamics reflected on the overall physiological diversity. At 30 days, a microbial succession was clearly highlighted. The relative abundance of Streptococcus sp. and especially St. thermophilus decreased, while that of Lactobacillus casei, Lactobacillus sp., and especially Lactobacillus paracasei increased consistently. Despite the lower relative abundance compared to St. thermophilus, mesophilic lactobacilli were the only organisms positively correlated with the concentration of FAAs, area of hydrophilic peptide peaks, and several VOCs (e.g., alcohols, ketones, esters and all furans). This study showed that a core microbiota was naturally selected during middle ripening, which seemed to be the main factor responsible for cheese ripening.