Sn. Jha et S. Prasad, DETERMINATION OF PROCESSING CONDITIONS FOR GORGON NUT (EURYALE FEROX), Journal of agricultural engineering research, 63(2), 1996, pp. 103-111
Gorgon nuts are processed for their kernels in expanded form and this
is known as makhana in India. Operations involved in the traditional m
ethod of processing make it laborious, time consuming and costly. This
paper reports an investigation into the effect of five combinations o
f operations on recovery of makhana, viz., (1) roasting and popping; (
2) drying, roasting and popping; (3) drying, tempering, roasting and p
opping; (4) first roasting, tempering, second roasting and popping; an
d (5) drying, first roasting, tempering, second roasting and popping.
The design of the experiments was based on response surface methodolog
y and they were conducted using thin-layer drying and a manual roastin
g method. The best combination of operations, based on the recovery of
grade 1 makhana, was found to be number 5 above, that is, drying, fir
st roasting, tempering, second roasting and popping. The data was anal
ysed to find the optimum processing conditions, to give 97% grade 1 ma
khana. These were found to be a combination of first roasting of dried
nut (moisture content 33% d.b.) at 335 degrees C for 3.9 min, temperi
ng for 23 h and second roasting at 335 degrees C for 2.8 min. These co
nditions reduced the processing time to less than one-half as compared
with the traditional method. (C) 1996 Silsoe Research Institute