Microbial dynamics in industrial blue veined cheeses in different packaging

Functional changes in Bleu d'Auvergne cheese during ripening

The authentic characteristics of the famous Bleu d'Auvergne cheese were studied. Many parameters were analysed during the ripening of cheeses. Migrations of Na and Ca ions, associated with a pH gradient, occurred between the rind and the core. At 34 days, this cheese had a high salt content (2.87 %), contributing to 23 % of the recommended sodium intake for adults, but significant calcium (6.14 g/kg) and vitamin B12 (1.14 µg/100 g) levels. Thus, a 40 g serving contributed to 25 % of the population reference intake for Ca and 11 % of the adequate intake for B12. Proteolysis, yeast and mould counts strongly increased. Lactococcus and Streptococcus were predominant and correlated with B2 and B6 levels. Bleu d'Auvergne was characterised by salty taste, blue odour and aroma. This cheese has a noticeable B vitamins concentration, but the level of salt should be reduced to meet the nutritional guidelines, possibly by implementing alternative salting methods.

Microbiological quality of tempeh with different wraps: banana leaf versus plastic

Tempeh is a traditional Indonesian fermented food widely consumed and became staple food in some Indonesian diet. Commercially, tempeh is available in banana leaf or plastic wraps. The wraps are not only important for fermentation and giving final form of tempeh,  but also potential source of food microbiome. This study aimed to investigate the effect of different packaging materials on the lactic acid bacteria (LAB) quantity and community composition of tempeh from three manufacturers with different production environments. Each tempeh wrapped with banana leaf or plastic during the fermentation process and then LAB from every tempeh sample were quantified using qPCR and plate count method. Terminal Restriction Fragment Length Polymorphism analysis was carried out to assign bacterial community composition from these samples. The LAB population quantity of fresh tempeh from three manufacturers were essentially similar around 10 log CFU/g. However, there is a difference in the proportion of cultured and uncultured bacteria. Principal Coordinate Analyses based on Bray-Curtis similarity matrices showed an apparent clustering pattern for tempeh samples according to tempeh manufacturers. Meanwhile, packaging materials did not significantly influence changes in  bacterial community composition. The result of this work could be used for determination, authentication, and improvement of tempeh quality.