|
|
Hodnocení jakostních parametrů kozích jogurtů v závislosti na vstupní surovině
Němcová, Vendula
The aim of the work was to evaluate the physico-chemical and microbiological parameters of organic goat yoghurts and milk, which was used for their production. The results were evaluated depending on the season and storage time of yoghurts. Sampling took place during spring, summer, autumn and winter. The sampling schedule during storage was chosen according to the shelf life given by the producer with the possibility of extending the shelf life of the product. The evaluated parameters included dry matter, fat, protein and lactose content, titratable and active acidity and microbiological analysis (total number of microorganisms, lactic acid bacteria, psychrotrophic microorganisms, coliform bacteria, enterococci and micromycetes). Goat's milk and, depending on it, yoghurts were subject to seasonal changes in composition with a higher dry matter content in winter and lower in summer. These differences were also reflected in the different titratable acidity and the total number of microorganisms. No coliform bacteria were present in the yoghurts. Enterococci, psychrotrophs and micromycetes (mostly yeasts) have been reported. Between the 3rd and 13th day of storage the number of psychrotrophs and micromycetes increased significantly. For yeasts and molds, another significant increase followed between the 18th and 24th day of storage. Only slight post-acidification was observed during yoghurt’s storage.
|
guest ::
