Kothakota et al.

Figure 1. Spray-dryer (S.M. Scientech, India)

Moisture content

Hygroscopicity

The moisture content was determined by the hot

Hygroscopicity was determined according to

air oven method using two gram of powder is

the method proposed by (Cai and Corke, 2000),

taken in pre weighed Petridis and kept in oven at

with some modifications. Samples of powder

105°C for 2 hrs. Thereafter, the sample was cooled

(approximately 1g) were placed at 25°C in a container

in a desiccators, weighed and re-dried for 2 hrs.

with NaCl saturated solution (75.29% RH). After one

The process was repeated until a change in weight

week, samples were weighed and hygroscopicity

between the successive dryings at 2hr intervals was

was expressed as gram of adsorbed moisture per

not more than 2 mg (Jittanit et al. , 2010). The weight

100 g dry solids (g/100 g). Dahi powder from each

loss after drying in the oven was used to calculate the

drying run was reconstituted with the proportion 37

moisture content of dahi powder and was expressed

g of powder per 100 g of Lukewarm distilled water

on wet basis (WB).

(40 o C) in order to make them to be comparable with

the fresh dahi.

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