Jf. Hardham, Effect of increased beta-lactoglobulin and whey protein concentration on the storage stability of UHT processed milk, AUST J DAIR, 54(2), 1999, pp. 77-83
The effects of addition of a beta-lactoglobulin-enriched powder (beta-fract
ion) (0.015-0.375 g/100 g milk) or whey powder (0.26-2.5 g/100 g milk) on t
he storage stability of UHT processed milk was examined. Increasing the whe
y protein content of milk by addition of beta-fraction or whey powder to ra
w milk delayed the onset of age-gelation in UHT milk samples. Addition of l
ow concentrations of beta-fraction usually delayed gelation time by 4-8 wee
ks, while addition of larger amounts of beta-fraction or whey powder result
ed in a further extension of time before gelation was apparent. The gelatio
n occurred in the upper creamy layer of the sample and there was no increas
e in product viscosity normally associated with age-gelation. There was no
clear trend observed on the effect of seasonal differences in milk composit
ion on the gelation time.