4.3 Drying Kinetics of Tamarind Paste
The maltodextrin concentration was varied in 3 levels of 0.30, 0.45, and 0.6 kg MD/kg TS, whereas the surface temperature was at 120, 130, and 140?C. In terms of moisture content, the samples initially had moisture of 137.08 to 235.91% (d.b.). They were dried on the drum until the equilibrium moisture reached. The moisture ratios (MR) were plotted against the drying times at given temperatures as shown in Figure 4.2 (a), (b), and (c). It was observed that the moisture ratio rapidly decreased with the time, especially at the high temperature of 140?C. The temperatures at 120, and 130?C were not much affected on the drying kinetics of different maltodextrin fractions. Obviously, the maltodextrin fraction had an influence on the drying kinetics. Higher fraction gave rise to higher drying rate due to lower initial moisture content. The equilibrium moisture contents of any conditions were tabled in Table 4.3. However, the desired final moisture content was 5% (d.b.) according to Jaya and Das (2004).
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