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

Abstract

The study was conducted to observe the shelf life Nga-pi, produced with improved method, under various storage conditions. Acetes and Mysid shrimps collected from Chowfalldandi fish-landing center of Cox’s Bazar were subjected to improved processing technique for 15 days and Nga-pi was prepared. Then it was srored for 180 days in three packing conditions (locally available mospata which is used to cover Nga-pi at Cox’s Bazar region, open polythene pack and air-tight plastic pack) at three storage temperatures (room, refrigeration and frozen temperature). Initial moisture content of Nga-pi was 57.18% which reached to 63.03% in air-tight polythene pack at frozen temperature (−18±0.1 °C) at the end of storage. The initial value of protein content was 29.78% which decreased to 15.86% in open polythene pack at frozen temperature and lipid content decreased to 4.0% in open polythene pack at refrigeration temperature (5±0.5 °C) from initial value of 5.05% at the end of storage. Initial value of TVB-N was 18.0 mg 100g⁻¹; at the end of storage the highest value was found 36.3 mg 100g⁻¹ in mospata at room temperature (28±2 °C) and the initial value of NPN 2.12 mg 100g⁻¹ increased to 4.0 mg 100g⁻¹ at room temperature in open polythene pack at the end of the storage. The pH value of Nga-pi was 8.1 at initial stage; which declined to 5.42 in mospata at room temperature at the end of storage period. For aerobic plate count the initial value was 2.11×103 (CFU g⁻¹); which reached to 8.60×109 (CFU g⁻¹) in mospata at room temperature at the end of storage.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 quite slowly at frozen temperature in improved Nga-pi and air-tight polythene pack was better for it’s storage than mospata or open polythene pack.