Improved Nga-pi : preparation and changes in it’s quality parameters under various storage conditions

This study was conducted on the improvement of production method of Nga-pi and to observe the shelf life of laboratory prepared Nga-pi under various storage conditions in the Department of Fisheries Technology, Bangladesh Agricultural University, Mymensingh. For the production of Nga-pi in laboratory applying improved techniques, Acetes and Mysid shrimp were used as raw material which were collected from Chowfalldandi fish-landing center at Cox’s Bazar and were preserved in ice, then transported to Mymensingh in an insulated box. Whole process of Nga-pi production was completed within 15 days. Initial value of percent moisture content of laboratory prepared improved Nga-pi was found 57.18 which reached to 63.03 in air-tight polythene pack at frozen temperature (-18±0.1)°C after 180 days of storage. The initial value of percent protein content obtained 29.78 which decreased to 15.86 in open polythene pack at frozen temperature (-18±0.1)°C after 180 days of storage. In the case of percent lipid content the initial value was found 5.05, after 180 days of storage which decreased to 4.00 in open polythene pack at refrigeration temperature (5±0.5)°C. Initial value of TVB-N was 18.00 (mg/100g); after 180 days of storage the highest value was found 36.30 (mg/100g) in mospata at room temperature (28±2)oC and the initial value of NPN was 2.12 (mg/100g), after ‘180’ days of storage the highest value was found 4.00 (mg/100g) at room temperature (28±2)°C in open plastic pack. The pH value of Nga-pi was 8.10 at initial stage; after ‘180’ days of storage the value was declined to 5.42 in mospata at room temperature (28±2)oC. For aerobic plate count the initial value was 2.11 × 103; after ‘180’ days of storage the value reached to 8.60× 109 in mospata at room temperature (28±2)oC. The results showed that the moisture content, TVB-N value and bacterial load increased during ‘180’ days of storage at all the storage temperatures but at frozen temperature (-18±0.1)oC. the rate was slower.