Effect of Whey Protein Isolate on the Properties of Freeze Dried aloe vera (Aloe barbadensis Mill) Powder

Abstract

The effect of whey protein isolate concentrations (10%, 15% and 20%) as carrier agent on the properties of freeze dried aloe vera powder was studied. Addition of whey protein isolate in aloe vera juice yielded powder with free flowable properties. The moisture content and water activity of the freeze dried powder decreased with incorporation of carrier agent. Colour properties observed on the basis of L*, a* and b* revealed that lightness (L*) of the powder increased with incorporation of whey protein while a* and b* decreased. Highest L* values (86.87) was observed at 20% of concentration. Water solubility, swelling capacity, dissolution time, tapped and bulk density increased whereas the water absorption index, hygroscopicity and cohesiveness measured in terms of Hausner ratio of the powder decreased with incorporation of whey protein. Powder recovery improved with addition and increasing concentration of whey protein. Carr index and Hausner ratio measured showed the better flow properties of the powder. Storage period significantly affected the physical and functional properties of the powder.