Effect of protein concentration, pH, lactose content and pasteurization on thermal gelation of acid caprine whey protein concentrates.
The influence of pH (4.5-6.5), sodium chloride content (125-375 mM), calcium chloride content (10-30 mM), protein concentration (70-90 g/l) and lactose content on the gel hardness of goat whey protein concentrate (GWPC) in relation to the origin of the acid whey (raw or pasteurized milk) was studied using a factorial design. Gels were obtained after heat treatment (90 degrees C, 30 min). Gel hardness was measured using texture analyser. Only protein concentration and pH were found to have a statistically significant effect on the gel hardness. An increase in the protein concentration resulted in an increase in the gel hardness. GWPC containing 800g/kg protein formed gels with a hardness maximum at the pHi, whereas GWPC containing 300 g/kg protein did not form true gels. Whey from pasteurized milk formed softer gels than whey from raw milk. A high lactose content (approximately 360 g/kg) also reduced the gelation performance of GWPC.
Bordenave-Juchereau
Stéphanie
S
Laboratoire de Biotechnologies et de Chimie Bio-organique, CNRS FRE 2766, UFR Sciences, Batiment Marie Curie, Avenue Michel Crepeau, La Rochelle, France. sbordena@univ-lr.fr
Almeida
Bruno
B
Piot
Jean-Marie
JM
Sannier
Frédéric
F
D000818:Animals; D002122:Calcium Chloride / Q000032:analysis; D003612:Dairying / Q000379:methods; D005782:Gels; D006041:Goats; D006863:Hydrogen-Ion Concentration; D007785:Lactose / Q000032:analysis*; D008894:Milk Proteins / Q000032:analysis*; D012965:Sodium Chloride / Q000032:analysis; D000067816:Whey Proteins
D005782:Gels; D008894:Milk Proteins; D000067816:Whey Proteins; D012965:Sodium Chloride; D007785:Lactose; D002122:Calcium Chloride