Influência da microbiota psicrotrófica no rendimento de queijo Minas Frescal elaborado com leite estocado sob refrigeração / Psychrotrophic bacteria present in refrigerated milk on Minas Frescal cheese yield effect
Rodrigo Rezende Cardoso
DATA DE PUBLICAÇÃO
The raw milk storage under cooling temperatures selects the psychrotropic bacteria growth including species able to produce heat resistant proteases and lipases that are usually associated with milk quality deterioration. The decrease in the cheese production yield is an important problem associated with the psychrotrophic bacteria growth in the refrigerated raw milk. This work aimed to evaluate the relation between the psychrotrophic bacteria population present in the cooled raw milk and the yield of Minas Frescal cheese production. The raw milk was stored at 10 C, for up to four days, it was pasteurized, and daily used for the Minas Frescal cheese production. Concomitantly, the number of psychrotrophic, proteolytic and lipolytic psychrotrophic bacteria and protease and lipase activity was evaluated in the raw milk. The raw milk maintenance at 10 C made possible the psychrotrophic bacteria growth, with an increase of two logarithmic cycles in the proteolytic psychrotrophic bacteria population and of, approximately, three logarithmic cycles in the lipolytic psychrotrophic bacteria population, after four days of storage. The protease and lipase activities increased during the refrigerated raw milk storage, presenting superior values to the ones of the recently milked milk. A decrease of 6.78% in liters of milk per kg of cheese and 6.38 % in grams of total solids of cheese per liter of milk when the product was done with cooled milk stored for four days, was observed. The psychrotrophic bacteria number present in that milk varied from 108 CFU mL-1 to 109 CFU mL-1, and the proteolytic and lipolytic psychrotrophic bacteria populations were higher than 107 CFU mL-1. For the same storage period, an increase in the total nitrogen, fat and total solids concentrations in the serum from the Minas Frescal cheese production, was verified. It was estimated that, for an industry able to process 50.000 liters of milk per day, designating 33% of this amount to produce Minas Frescal cheese, the economic losses associated with the decrease in the cheese production are estimated in US$ 15,480.00 per month.
- Processo de fabricação de queijo Minas Frescal probiótico elaborado com leite de cabra.
- Influencia da adição de CO2 ao leite sobre as caracteristicas fisico-quimicas e microbiologicas do queijo minas frescal
- Bactérias psicrotróficas e atividade proteolítica no leite cru refrigerado
- Effect of milk and retentate heat treatment on quality of light mins frescal cheese manufactured by ultrafiltration
- Rendimento, composição e análise sensorial do queijo minas frescal fabricado com leite de vacas mestiças alimentadas com diferentes volumosos