Coalho cheese with incorporated chitosan and as a coating: effect on the viability of Staphylococcus aureus and sensory acceptance

• Autor(a) principal: Barros, Dayane de Melo
• Data de Publicação: 2019
• Outros Autores: Moura, Danielle Feijó de, Rocha, Tamiris Alves, Santos, Anderson Emmanuel Silva, Silva, Michelle Rose de Oliveira, Ferreira, Silvio Assis de Oliveira, Fonte, Roberta Albuquerque Bento da, Machado, Erilane de Castro Lima
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Semina. Ciências Agrárias (Online)
• Texto Completo: https://ojs.uel.br/revistas/uel/index.php/semagrarias/article/view/35183
• topic: Conservation; Contamination; Dairy product; Quality control.; Conservação; Contaminação; Controle de qualidade; Produto lácteo.

Abstract: Coalho cheese is a dairy product typical of the Northeast region of Brazil and widely consumed by the population; however, the poor quality of the raw material used in association with the absence of standardization in the manufacturing process makes it susceptible to microbial contamination, mainly by Staphylococcus aureus. The objective of this study was to evaluate the influence of chitosan as a coating and incorporated in coalho cheese on S. aureus viability and the sensorial acceptance of the cheese. For this, coalho cheeses were made with chitosan in the coating or added to the curds at 5 mg mL-1, 10 mg mL-1 and 15 mg mL-1 and 1 mg g-1, 2 mg g-1 and 4 mg g-1, respectively. Products without chitosan (C) and 1% acetic acid (CA) were used as controls. The bacterial inhibition of chitosan in the artificially contaminated samples was assessed by comparing the viable cell count of S. aureus (ATCC 6538) in each treatment over five time intervals (0, 4, 8, 12 and 16 d storage). Product C was evaluated for moisture and fat content. The sensorial and shelf stability analyses were performed with the control and chitosan treated samples at the most efficient antibacterial concentrations. The sensorial analyses were performed with 100 consumers. Chitosan antimicrobial activity was observed in all treatments; however, the highest concentrations of chitosan added as a coating and to the cheese, 15 mg mL-1 and 4 mg g-1, respectively, inhibited S. aureus. The moisture and fat contents met the standards established by the Brazilian legislation. Regarding stability, the samples complied with the regulatory microbiological limits and presented acceptable pH, acidity and water activity values. As far as sensorial acceptance was concerned, the scores corresponded to hedonic concepts between "I liked it slightly" and "I liked it a lot", with an improvement in the texture of the products when chitosan was incorporated. Acceptability values were higher than 70%, except for the taste the products with chitosan covering them, which was 68.3%. It can be inferred from the results that the use of chitosan as a coating and incorporated in coalho cheese is a favourable alternative for the preservation of this product and has potential commercial applicability.