Qualidade de queijo minas frescal preparado com leite com diferentes quantidades de células somáticas

Abstract

-The objective of this work was to evaluate the effects of using bulk milk with different somatic cell counts (SCC) on the quality of minas frescal cheese. A randomized complete block design was used, with 3x5 factorial treatments, with three SCC levels (low, 125,000 cells mL -1 ; intermediate, 437,000 cells mL -1 ; and high, 1,053,000 cells mL -1 ) and five storage durations. Cheese was vacuum-packed in plastic bags and analyzed after 2, 9, 16, 23 and 30 days of storage at 4 o C. Somatic cell counts did not affect dry matter, fat, ash content, pH, free fatty acid concentrations and sensory parameters of minas frescal cheese. However, SCC in milk increased losses of protein in whey and decreased the cheese protein content. These changes did not affect the moisture-adjusted cheese yield and proteolysis during 30 days of storage. An interaction effect between SCC and time of storage was observed for firmness and sensory grades of cheeses. Results indicated that raw milk used to produce minas frescal cheese should not contain high SCC, in order to avoid lower acceptance of the product after 30 days of storage.Index terms: cheese quality, proteolysis, somatic cell count. Qualidade de queijo minas frescal preparado com leite com diferentes quantidades de células somáticasResumo -O objetivo deste trabalho foi avaliar o efeito do uso de leite com diferentes contagens de células somáticas (CCS), na qualidade do queijo minas frescal. Utilizou-se delineamento de blocos ao acaso, em esquema fatorial 3x5, com três níveis de CCS (baixa, 125.000 células mL -1 ; intermediária, 437.000 células mL -1 ; e alta, 1.053.000 células·mL -1 ) e cinco tempos de armazenamento. Os queijos foram embalados a vácuo, em embalagens de plástico, e analisados após 2, 9, 16, 23 e 30 dias de armazenamento a 4 o C. A contagem de células somáticas não afetou a matéria seca, a gordura, as cinzas, o pH, a concentração de ácidos graxos livres e os parâmetros sensoriais do minas frescal. A CCS no leite aumentou as perdas de proteína no soro e diminuiu o teor de proteína no queijo. Essas alterações não afetaram o rendimento com umidade ajustada e a proteólise durante 30 dias de armazenamento. Houve interação entre a CCS e o tempo de armazenamento, quanto à firmeza e às notas sensoriais dos queijos. O leite cru usado para a produção do queijo minas frescal não deve conter alta CCS, para evitar menor aceitação sensorial do produto após 30 dias de armazenamento.Termos para indexação: qualidade do queijo, proteólise, contagem de células somáticas.

Influence of Somatic Cell Removal on Milk Quality and Yield

“…This downward trend in the yield of cheese made from high-SCC milk was also observed by Andreatta et al [22], who stated that the decrease in cheese yield was influenced by the action of the plasmin enzyme found together with the inactive precursor, plasminogen, increasing the rate of proteolysis in milk and thus reducing the industrial yield, confirming the results described by Leitner et al [23] and differing from the results of this study.…”

Cheese yield in Brazil: state of the art

“…This advantage in the production of products is mainly due to higher proportion of solids from buffalo milk compared to cow's milk. It is worth noting that the health of the mammary gland is very important when it comes to the quality of milk, since the microbiological and immune aspects invariably expressed by the total bacterial count and somatic cells have high ability to change milk constituents and cheese yield (Oliveira et al, 2006;Andreatta et al, 2009;Mikulec et al, 2012;Montanhini et al, 2013;Coelho et al, 2014).…”

“…In the field of the dairy production industry, the adverse effects of mammary gland infection is explained by the fact that the rise in SCC is directly related to the decrease in productivity, changes in chemical composition of milk (fat, lactose and casein), in the activity of enzymes in the clotting time, and the yield and quality of milk products (Andreatta et al, 2009;Mikulec et al, 2012;Montanhini et al, 2013;Coelho et al, 2014;Ribas et al, 2014). Sollecito et al (2011) see changes in milk composition as a problem for the industry, since they hinder yield, quality and stability (shelf life) of the derivatives.…”

“…The formulas involving this reasoning are those used by Katili et al (2006), Damián et al (2008), Oliveira et al (2008), Silva et al (2012), and Santos et al (2013) (Equation 1), Andreatta et al (2009) (Equation 1.1) and Martins et al (2012) (Equation 1.2). Silva (2005) Evaluate the effect of different anticoagulants on minas fresh cheese yield.…”

“…Oliveira et al (2008) Evaluate the yield of lactating buffaloes fed different sources of fat. Andreatta et al (2009) Evaluate the effect of using milk with different somatic cell counts (SCC) on the quality of minas fresh cheese.…”