Tempo de maturação altera o teor de peptídeos bioativos e o perfil de ácidos graxos do queijo de coalho artesanal

Abstract

Among the artisanal cheeses in Brazil, coalho cheese stands out as one of the main ones and its consumption is already part of the food habit of the Northeastern population. The present work aimed to present the physicochemical, microbiological aspects and fatty acid profile of artisanal coalho cheese matured for 30, 45 and 60 days, as well as to verify if there are peptides with bioactive potential in its composition. For that, 16 samples of artisanal coalho cheese made with milk from Jersey cows were used in a dairy located in the municipality of São Gonçalo do Amarante/RN. A completely randomized lineation was adopted, with 04 maturation periods (0, 30, 45 and 60 days). Physicochemical (pH, total solids, moisture, non-fat solids, fat in total solids, protein, ash, fatty acid profile) and microbiological (Salmonella sp, Listeria monocytogenes, total and thermotolerant coliforms, Sthaphylococcus aureus) analyzes were performed on cheese samples, in addition to assays of antioxidant, antihypertensive bioactivity through ACE and antimicrobial inhibition of the peptides extracted from the samples. As for aged cheeses, compared to the sample at time 0, there was a linear increase in the total solids content and a decrease in the moisture content, so the cheeses with 30, 45 and 60 days were classified as having low moisture content (below 35.9%). The fat in the total solids linearly reduced its content as the days of maturation progressed, in this way, the fresh coalho cheese was classified as "fat" (47.59%), and in the other periods as to be classified as “semi-fat” (41.53 to 43.06%). And DDE content, when compared to fresh cheese, there was an increase in the periods of 30 and 45 days, with a subsequent reduction at 60 days. There was a quadratic effect for the protein content, with a minimum point of 33.84% when the cheese was aged for 45 days. The matured cheese samples evaluated had a pH below 5, being more acidic compared to fresh coalho cheese, whose average was 5.25. Regarding ash, there was an increasing linear effect with maturation time. Twenty-seven fatty acids were identified in the cheeses, being 15 saturated, 07 monounsaturated and 05 polyunsaturated, with a linear reduction of fatty acids considered essential during the course of maturation. As for the microbiological quality, the fresh coalho cheese presented satisfactory results for the agents studied. It was found that the fractions of water-soluble peptides from all periods evaluated presented antioxidant and antihypertensive potential with ACE inhibition, and the maturation process potentiated these capacities, with a decline in activities observed at 60 days. It also presented antimicrobial activity against gram-positive and gram-negative bacteria, with maturation being directly related to this effect, since the level of antimicrobial activity increased with the course of the maturation period, reaching better inhibition results at 60 days.