Amp. Gomes et Fx. Malcata, DEVELOPMENT OF PROBIOTIC CHEESE MANUFACTURED FROM GOAT MILK - RESPONSE-SURFACE ANALYSIS VIA TECHNOLOGICAL MANIPULATION, Journal of dairy science, 81(6), 1998, pp. 1492-1507
Production of caprine milk has been rising steadily, partially because
of its good nutritional value; the possibility of improving nutrition
al benefits by adding probiotic species such as Bifidobacterium lactis
and Lactobacillus acidophilus was assessed. The manufacturing process
of a traditional semi-hard goat cheese was technologically modified t
o optimize the process. The amount of starter inoculum, the concentrat
ion of salt, the addition of a protein hydrolysate, and the ripening t
ime were varied to improve the microbiological, biochemical, and senso
ry properties of the cheese. Bifidobacterium lactis was able to grow s
lightly (up to 3 x 10(8) cfu/g), but growth was dependent on the physi
cochemical characteristics of the cheese. Lactobacillus acidophilus di
d not grow substantially in any of the experimental cheeses, and maxim
um numbers did not exceed 6 x 10(7) cfu/g. Concentrations of lactic ac
id and acetic acid increased throughout cheese manufacture, indicating
that production of these acids was uncoupled from growth. Viability o
f the probiotic strains during ripening was sufficient to yield number
s that were above the accepted threshold (10(6) cfu/g) for a probiotic
effect. Both strains contributed significantly to ripening, especiall
y in the formation of low molecular mass peptides and amino acids, but
lipolysis was not greatly affected. Statistical analyses using respon
se surface methodology indicated that the manufacture of goat cheese c
ould be optimized by the addition of 0.30% (vol/wt) milk hydrolysate,
3 x 10(7) of viable B. Lactis and 7 x 10(6) of viable L. acidophilus c
ells/ml of milk, respectively, 3.50% (wt/wt) salt, and ripening for 70
d.