Drying Rate and Product Quality Evaluation of Roselle (Hibiscus sabdariffa L.) Calyces Extract Dried with Foaming Agent under Different Temperatures

Table 2

Predicted drying time of roselle extract with foam at various air conditions.

Aw/RH	Drying time (minutes)
	30°C	40°C	50°C	60°C	70°C	80°C
0.0	163.0	131.6	93.3	84.9	66.9	55.5
0.2	167.6	134.9	95.4	86.5	67.8	56.0
0.4	184.6	145.3	101.0	90.0	69.7	56.9
0.6	nd	nd	187.7	101.5	73.9	58.8
0.8	nd	nd	nd	nd	99.1	63.6

: not dried (equilibrium moisture of the product was upper 10% wet basis).