Specific effect of high-pressure treatment of milk on cheese proteolysis.
The extent of primary and secondary proteolysis of cheeses made from raw (RA), pasteurized (PA, 72 degrees C, 15 s) or pressure-treated (PR, 500 MPa, 15 min, 20 degrees C) goats' milk was assessed. Modifications in cheese-making technology were introduced to obtain cheeses with the same moisture content, and thus studied per se the effect of milk treatment on cheese proteolysis. The PR milk cheese samples were differentiated from RA and PA milk cheeses by their elevated beta-lg content, and by the faster degradation of alphas1-, alphas2- and beta-CN throughout ripening. Non-significant differences were found in either pH 4.6 soluble-nitrogen or trichloracetic acid soluble-nitrogen contents of cheeses. However, the pasteurization of milk decreased the free amino acid production in cheese. The RA milk cheeses had the highest amount of proline and the lowest concentrations of serine, tyrosine, arginine and alpha-aminobutyric acid, whereas PR milk cheese showed higher levels of arginine.
Buffa
Martín
M
Centre Especial de Recerca Planta de Tecnologia dels Aliments, CERPTA, XiT, Departament de Ciència Animal i dels Aliments, Facultat de Veterinària, Universitat Autònoma de Barcelona, 08193 Bellaterra Spain.
Guamis
Buenaventura
B
Trujillo
Antonio J
AJ
D000596:Amino Acids / Q000032:analysis*; D000818:Animals; D002611:Cheese / Q000032:analysis*; D005285:Fermentation; D005511:Food Handling / Q000379:methods; D005524:Food Technology; D006041:Goats; D006863:Hydrogen-Ion Concentration; D006874:Hydrostatic Pressure; D008892:Milk / Q000737:chemistry; D008894:Milk Proteins / Q000737:chemistry / Q000378:metabolism*
D000596:Amino Acids; D008894:Milk Proteins