عنوان مقاله [English]
Estimation of fillet biochemical composition and processing yield is primary needs for fish processing. Present study was aimed to investigate for determining fillet biochemical composition and processing yield of bighead (Hypophthalmichthys nobilis) for nutritional labeling and economical estimation of its products by regression equations. For this purpose 55 specimen of bighead were applied in range of marketing size and their fillet yield, moisture, lipid, protein, ash and energy content were measured in wet and dry weight. Then the relationships between these parameters with fish size were considered and types of their relationships were determined. According to obtained results, the relationship between logarithm of moisture and ash with logarithm of total length and weight were inverse linear regression (P<0.05) but the relationships between lipid, protein, energy content and fillet yield with total length and weight were positive linear regression (P<0.05). In generally these equations are in form Y=bX±a. with regarded to these relationships and determining their equations, it could be sorted fishes by machine, then it could be done by obtained equations for economical estimation and determining moisture, lipid, protein, ash and energy content of each group for nutritional labeling.