Banca de DEFESA: MARINA TAVARES TEIXEIRA DE MELO

Quality, Composition, and Sensory Aspects of Milk Produced in Seropédica, RJ

Dairy cattle farming; Milk quality; Sensory analysis; Fatty acid profile; Family farming; Cheese quality

Seropédica (RJ) is the city in Baixada Fluminense with the highest milk production, primarily composed of small producers, many of whom operate informally. The dairy industry in the region has significant economic and social impacts.The objective of this study was to evaluate quality, composition and sensory aspects of milk produced in Seropédica, RJ. A sample of 10% of Seropédica producers was evaluated. Technical visits were conducted, questionnaire was applied to collect information on socioeconomic aspects, production practices and milking environment, with the aim to classify the different production systems. Additionally, raw milk samples were collected and the quality was assessed through titratable acidity analysis, somatic cell count (SCC), total bacterial count (TBC), and verification of antibiotic residues. Only milk samples that met the standards established by current legislation were included in the subsequent stages of the study. These milk samples, along with commercial milk samples, were subjected to proximate composition analysis, including fat content, non-fat solids, protein, lactose, water content, freezing point, and total solids. The samples were pasteurized at 63°C for 30 minutes and underwent microbiological analysis to detect the presence of Enterobacteriaceae/ml. Subsequently, sensory evaluations were conducted using the Rate-All-That-Apply (RATA) method, acceptance tests and purchase intention. Furthermore, raw and pasteurized milk samples were analyzed for fatty acid profile by gas chromatography, color, and water activity. The results showed that only 33% of the samples from different producers complied with the parameters established by current legislation. The milk produced by local farmers exhibited higher fat content, stronger perception of sensory attributes, better sensory acceptance and greater purchase intention compared to commercial milk. Regarding the fatty acid profile, producer milk demonstrated superior quality, with higher levels of desirable fatty acids (DFA), lower levels of undesirable fatty acids (UFA), and lower atherogenicity (AI) and thrombogenicity (TI) index. The findings of this study indicate that production system practices directly affect milk quality and highlight the potential of Seropédica for producing cow’s milk with superior quality compared to commercially available pasteurized and UHT milk.