An Analysis of the Physico-Chemical Characteristics of Hilsa (Hilsa Ilisha) Fish, and Purification and Characterization of Two Lipases From its Dorsal Part

Abstract

A comparative analysis on the nutrient contents of six different parts of Hilsa fish was performed. Most of the nutrient contents of different parts were varied remarkably. The moisture and ash content of the different parts of hilsa fish were found in the ranges of 13.00-54.87% and 1.7-3.8% respectively. The ranges in the values of oil, protein, free sugar and polysaccharide composition of hilsa fish were 9.61-22.78%, 5.5-23.18%, 0.053-0.09%, and 0.03-0.065% respectively. The minerals such as iron, calcium and phosphorus were found to be varied from 199-212 mg%, I 60-180 mg% and 259-278 mg% while the vitamins such as BI and 82 contents were varied in the ranges of 0.35-0.48 mg% and 2.44-2.98 mg% respectively. The oils extracted from different parts of hilsa fish were also characterized with respect to its physico-chemical prope11ies such as specific gravity, refractive index, saponification value, iodine value, peroxide value and acid value. The specific gravity and refractive index of oil were varied from 0.920 to 0.932 and 1.4700 to 1.4722 respectively. The saponification value, iodine value, peroxide value and acid value of the oils were found to be ranged from 180.28 to 194, 80. 70 to l 26.40, 7 to 10 and 4.16 to 12. 00, respectively. The oils, extracted from different parts of hilsa fish were stored at temperatures -10°C, 0°C and 25°C for 120 days. The hydrolytic deterioration of the oils was more pronounced at 25°C as compared to that from 0°C and -l 0°C.