RHEOLOGICAL PROPERTIES OF ACIDIFIED HEATED SKIM MILK AS AFFECTED BY THE ADDITION OFWHEY PROTEIN CON'CENTRA TES

Farrag, A.; V, NadIa M.; EI-Dln, Hala M. F.

doi:10.21608/jfds.2004.240074

RHEOLOGICAL PROPERTIES OF ACIDIFIED HEATED SKIM MILK AS AFFECTED BY THE ADDITION OFWHEY PROTEIN CON'CENTRA TES

Document Type : Original Article

Authors

Dairying department, NRC, Cairo, Egypt

10.21608/jfds.2004.240074

Abstract

The sHeet of heat treatment and addiUon of v they protein concentrates
(WPC) solution (3% protein) on the meological properties of acid skim milk gels was
investigated. Milk samples were pasteurized, boiled and UHT treated. WPC was
added to heated skim mitk at ratios of 0, 5. 10, 15, 20 and 2.5% vtv. G81 formation was
followed using thrombelastograpll to determine the gelatlon lime (r) and curd
firmness (K2<)). Coaxial viscometer was used to determine the changes in viscosity
during a cldlficaUon. R esulls I ndlcatad t hat Increasing the addition of WPC reduced
the gelation time (r) for both unheated and heated milk samples. The time required to
get curd firmness was Increased with increaSing WPC added for unheated and
pasteurized milk. Moroovef. gel IormatJon was lost in boiled and UHT milks The
viscosity of acidIfied gels decreased with Increasing the added WPC. The viscosity of
~cid\ned boiled skim m~k showed decreased values and weak gel. UHT treated skim
milk failed to form firm curd and Its viscosity was eHected slightly by acldtt1catlon.

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