MFSc

A study was undertaken for the preparation of fish crackers using a low
cost fish, threadfm bream (Nemipterus japonicus, Bloch). A method was
standardised for making crackers based on that generally followed in Malaysia.
Fish meat was mixed with various food additives such as starch, salt, sugar,
monosodium glutamate, colour and water, and stuffed into high-density
polyethylene casings as rolls, cooked, cooled, sliced and dried.
The parameters used for standardisation were starch source, fish: flour:
water proportion, mixing time and cooking condition. The various starch sources
studied were corn flour, refined wheat flour (maida), tapioca powder, sago
powder, and potato powder. The various fish: flour: water proportions used for the
study were 70:30:22.5, 60:30:27.5, 50:50:32.5, 40:60:37.5, and 30:70.42.5.
Ingredients were mixed for various periods, viz., 2,5,10,15, and 20 min. The
cooking conditions tried were steaming at atmospheric pressure for 20min, boiling
in boiling water bath for 60min, boiling in water bath at a temperature of 90°C for
30min and boiling in water bath at a temperature of 90°C for 60 min. The effect of
various additives and steps were assessed based on the extent of linear expansion
and sensory evaluation of fish crackers after frying. Samples that gave linear
expansion of more than 70 % alone were subjected to sensory evaluation. Based
on the tests, the following conditions were selected: corn flour as starch source,
fish: flour: water proportion of 60:40:27.5, mixing time of 15 minutes and
cooking by steaming for 20 min at atmospheric pressure.





Fish crackers prepared by the standardised method, were subjected to
storage studies at ambient temperature under various conditions of packing, vi= ..
dried & packed, dried & vacuum-packed, and dried, fried & packed, in laminated
polyester/polyethylene (50/300 gauge) pouches. The pouch had low permeability
to air and water vapour. Quality changes during storage were monitored at
appropriate time interval based on various tests, viz., total plate count and fungal
count sensory evaluation, linear expansion, moisture content, total volatile base
nitrogen content, trimethylamine content, peroxide value, thiobarbituric acid
value.
Dried fish crackers packed with or without vacuum remained acceptable,
with no significant reduction in sensory quality, for all the four months of study.
However, packing under vacuum showed significantly lower values for moisture
content, TVB-N content, TMA content, PV, TBA value, TPC, and fungal count,
probably on account of lower amount of air contained in the pouch. Fried
crackers, which are ready to consume, however, remained acceptable only for 45
days, possibly on account of its greater hygroscopicity and higher fat content.