Chemical composition and nutritional quality of short-ripened rennet cheeses produced by traditional methods

Abstract

The aim of the study was to determine the variability in the chemical composition and nutritive value parameters of smoked and unsmoked short-ripened rennet cheeses and unsmoked long-ripened rennet cheeses produced by traditional methods. The raw material for the production of short-ripened cheeses was pasteurized cows’ milk obtained from a dairy, whereas the long-ripened cheeses were manufactured from raw cows’ milk obtained from the producer’s farm. All three varieties of cheese examined were produced with commercial dairy starter cultures. The material for the study was collected in winter, directly at the producers’ retail outlets in southern and eastern Poland. The basic chemical composition was determined according to the Polish Standards, whereas the amino acid profiles of proteins from the cheeses were determined by ion-exchange chromatography. The result analysis revealed significant differences between the different varieties of cheese in terms of their water content, ranging from 32.2% to 42.1%, as well as protein content, which varied from 25.6% to 31.6%. Fat levels ranged between 22.2% and 24%, whereas total ash content amounted to 5.1-5.8%. The significantly highest salt content was found in unsmoked short-ripened cheeses. In all three cheese varieties, the total exogenous amino acid content was comparable, ranging from 46.17 g to 47.36 g/100 g protein, and that of endogenous amino acids varied from 52 g to 53 g/100 g protein. The biological value of proteins was determined by calculating to the chemical score (CS), as described by Mitchell and Block, and the essential amino acid index (EAAI), as described by Oser. A comparison of the results with the standard chicken egg white proteins showed that the limiting amino acids for all varieties of cheese were methionine and cysteine. On the other hand, a comparison with the FAO/WHO-suggested pattern of amino acid requirements (1991) for all age groups over 1 year of age showed that the limiting amino acids were methionine and cysteine in smoked and unsmoked short-ripened cheeses, and treonine in long-ripened cheeses. Considering the chemical indices, such as CS and EAAI, it may be concluded that the traditional rennet cheeses produced in southern and eastern Poland have a favourable amino acid composition of proteins and a high nutritive value..

Effect of metabolic activity of lactic acid bacteria and propionibacteria on cheese protein digestibility and fatty acid profile

“…Therefore, it can be concluded that the content of free methionine in rennet cheeses can not only be affected by factors such as maturation time, but also by the type of microorganisms used. This is supported by previous studies conducted by other researchers 51 , 52 . Each of the lactic streptococci, lactobacilli and propionic bacteria produces an enzyme specific to itself that can have varying effects on hydrolysis, thus affecting the final content of the free amino acid in rennet cheeses 51 .…”

Microbiological, sensory, and physicochemical quality of curd cheeses originating from direct sales

“…In as many as 76% of the samples, the number of microorganisms that demonstrated improper hygiene of the technological process ranged from >10 4 to 10 7 cfu/g [26]. As concluded by Knysz et al [27], cheeses produced on small farms using traditional methods with no pasteurization process or highly advanced technologies have a highly variable microbiological quality and nutritional value.…”

“…As concluded by Knysz et al . [ 27 ], cheeses produced on small farms using traditional methods with no pasteurization process or highly advanced technologies have a highly variable microbiological quality and nutritional value.…”

“…The observed differences in consistency may be associated with the different production processes used by the individual suppliers. Polish traditional curd cheeses are most often produced on small family farms from unpasteurized cow’s milk, in accordance with an old recipe [ 27 ]. The simplified manufacturing process of these products excludes the use of advanced technological solutions and production standards, which indicates that products from different manufacturers may exhibit a wide variety of quality traits.…”

“…It is important to note that there are no recommendations specifying the standard amount of fat and protein in curd cheeses from household production. Differences in the fat and protein content of the curd cheeses analyzed in this study may have resulted from the simplified production process, which excludes the use of advanced technological solutions or compliance with production standards [ 27 ]. Importantly, the protein and fat content in the final product is determined by the concentration of these components in the milk intended to be used for the production of curd cheese [ 42 ].…”