Changes in quality parameters of fish pickle prepared from Thai pangus (Pangasianodon hypophthalmus) at different storage temperatures

Abstract

Pickle from Thai pangas ((Pangasianodon hypophthalmus) was prepared using fresh
fish muscle, various hot spices, vinegar, sugar, salt, tomato sauce and tamarind were used as
ingredients. Chemical and microbiological changes in fish pickle were determined at different
storage temperatures. It was observed that, the TVB-N value increased progressively throughout
the storage period irrespective of storage temperature. However, in case of room temperature
(28°C to 32°C), the values increased rapidly compared to those of refrigeration(5°C to 8°C) and
frozen temperature (-18°C to -20°C). The TVBN value increased from 1.18±0.12 to
4.29±1.05, 4.45±0.51 and 2.05±0.04 mg/100g on day 15th at room, 73rd at refrigeration and
90that frozen storage temperature, respectively. On the other hand, the peroxide values increased
from 0.27±0.08 to 2.43±1.46, 2.96±2.01 and 1.26±1.93 meq/kg of oil, on day 15th at room,
73rdat refrigeration and 90that frozen storage temperature, respectively. The pH values of fish
pickle also changed throughout the storage period at different temperatures. The pH value
decreased from 4.41±0.26 to 3.99±0.21, 4.07±0.19 and 3.97±0.28, respectively on day 15th at
room, day 73rdat refrigeration and day 90th at frozen storage temperature. The bacterial load
(CFU/g)in pickle was found to increase at room temperatures (from 2.30×103 to 7.20×107).
However, the growth of bacteria was slower at refrigeration temperature (from 2.30×103 to
9.10×107) and at frozen temperature bacterial growth found negative (from 2.30×103 to
0.27×102). So, from the observation on the changes in different quality parameters at different
storage temperatures, it could be concluded that, the shelf life of Thai pangas fish pickle at room
temperature was shorter, in fact not more than 15 daysbut at refrigeration temperature fish pickle
may remain in acceptable condition more than 73 days and more than 90 days at frozen
temperature.