effect of different heating treatments during canning, on the amounts of some mineral elements (iron, zinc, copper, calcium and sodium) of silver carp (hypopthalmichthys molitrix)

in this investigation, the effects of the precooking (cooking with saturated steam, microwave and oven) and sterilization (115, 120 and 130 ° c, with same sterilization value) on the amount of iron, zinc, copper, calcium, sodium, of silver carp was studied during canning process. the results of measuring elements in the raw and precooked fish were ranged from 3.05 to 4.19 for copper, 71.45 to 82.85 for zinc, 32.18 to 40.70 for iron, 425.6 to 529.46 for sodium and 315.5 to 534.76 ppm for calcium, respectively. the results showed that different precooking treatments had no significant effect on the amounts of copper, zinc, calcium and sodium. after comparing different methods of precooking, steam cooking was recognized as the best way to preserve the mineral nutrient. in the final stage, with two kinds of filling media, canned samples were processed under three different temperatures (115, 120 and 130 ° c) with same sterilization value (7 min). results showed, the amount of sodium was increased after canning process. amounts of other elements were changed heterogeneously in all treatments. using 120°c and 130°c thermal regimes, achieved better results in maintaining the mineral nutrients. based on these results, the thermal regime of 115 ° c is not recommended for production canned silver carp.