Efeito do tipo de embalagem na formação de aminas biogênicas, características físico-químicas e perfil de textura do queijo azul

Abstract

Blue cheeses produced in Brazil are considered important for the economy and their production exceeds 10 million tons/year. They are characterized by the presence of the filamentous fungus Penicillium roqueforti, wich is responsible for giving the cheese its unique flavor and texture. Studies related to ripening and the use of different packaging contribute to the quality control and safety of this food. Among the biochemical events that occur during cheese ripening, proteolysis stands out, which consists of the degradation of caseins. Biogenic amines are generated through decarboxylation reactions, mediated by bacterial decarboxylases, which is the main pathway of amine formation in foods. This study aimed to evaluate the influence of vacuum plastic and aluminum packaging on the formation of biogenic amines in blue cheese and the impact on the physicochemical characteristics and texture profile. Bovine milk was used to manufacture the cheeses. After the growth of Penicillium roqueforti (14 days after the cheese puncture stage), the cheeses were packaged in different packages (aluminum and vacuum plastic) and ripened for 60 days at a temperature of 12°C. The experiment was carried out in 3 replicates and the cheeses were analyzed at 1, 15, 30, 45, and 60 days of ripening. Physicochemical analyses were performed to determine the centesimal composition of the cheeses (percentage of moisture, fat, protein, fixed mineral residue), chlorides (expressed as sodium chloride), proteolysis indices (extent and depth), pH, water activity, and texture profile, as well as the determination of bioactive amines. There was no significant effect of the type of packaging on moisture, fat, protein, fixed mineral residue, chlorides, and water activity. However, for the pH of the cheeses analyzed, there was a significant difference (P<0.05) between the means of the vacuum plastic packaging (5.38±0.29) and aluminum packaging (6.22±0.68), and the ripening time did not significantly influence (P>0.05) the pH of the cheeses. Regarding the proteolysis indices of the cheeses, the types of packaging did not differ from each other (P>0.05). In the aluminum packaging, the change in the extension and depth of the cheeses throughout the ripening process was not significant (P>0.05), while in the plastic packaging, the ripening time led to an increase in the proteolysis indices (P<0.05) of the cheeses. For the texture profile, the parameters analyzed (hardness, cohesiveness, elasticity, and chewiness of the blue cheeses) did not present any significant difference (P>0.05) concerning the type 10 of packaging and only the cohesiveness showed a significant difference (P<0.05) in the different packages over the ripening time. For the bioactive amines, the phenylethylamine content in the blue cheeses showed a difference between the packages, with an average of 9.71±7.30 mg/kg in aluminum packaging, significantly lower than 22.56±9.89 mg/kg in plastic packaging. Regarding ripening time, this amine did not show a significant difference in the cheeses packed in vacuum plastic (P>0.05); however, in the cheeses packed in aluminum, the phenylethylamine content increased over time (P<0.05). Spermine content in the cheese packaged in aluminum (156.93±85.94 mg/kg) was lower (P<0.05) than in the cheese packaged in plastic (244.72±63.75 mg/kg). Tyramine content showed a significant positive (P<0.05) Pearson correlation with the depth of proteolysis, and a negative correlation with cohesiveness and water activity, indicating that the greater the proteolysis of the cheeses and the lower the water activity, the higher the tyramine content in the blue cheeses. Serotonin correlated positively (P<0.05) with water activity, agmatine with fixed mineral residue, and spermidine with salt content. Spermine correlated negatively with pH and extent of proteolysis, and agmatine with pH (P<0.05). For the Principal Component Analysis (PCA) performed with the data obtained from the physicochemical parameters, texture profile and bioactive amine contents over time, PC1 was responsible for 46.96% of the variations and showed high positive correlations with serotonin (0.618), spermine (0.912), water activity (0.938), cohesiveness (0.995) and chewiness (0.929). Both packaging allowed the main factors related to the ripening of blue cheeses to evolve adequately. Regarding the biogenic amines, the analyzed correlations demonstrated how complex the biochemical interactions that occur during the ripening of blue cheeses are, leading to the formation of free amino acids, which through decarboxylation generate biogenic amines. Seeking to understand the dynamics of amine formation, as a function of factors such as packages, ripening temperature, and pH is important to minimize the formation of amines, making the cheeses safer.