Nutritional and microbiological assessment of shidhal, a semi-fermented fish product of Bangladesh

Abstract

The present study was conducted to evaluate the nutritional aspects (proximate composition, amino acid, Non-protein Nitrogen) and microbiological quality of the semi-fermented fish product locally known as chepa shutki or shidhal. Samples were collected from producers of Narsingdi and Mymensingh district as well as a control sample was prepared with proper hygiene and sanitation in the laboratory. Statistical analysis showed significant differences (p<0.05) among the samples. The organoleptic quality of the laboratory-prepared shidhal (LPS) and collected shidhal were evaluated on the basis of quality attributes such as color, odor, texture, insect infestation, overall quality and the result showed that the overall quality of laboratory-prepared shidhal was excellent whereas the samples from Narsingdi and Mymensingh were acceptable.

The values obtained from proximate composition, NPN content, and Total Plate Count (TPC) of bacteria of laboratory-prepared shidhal, samples collected from Narsingdi and Mymensingh were moisture (31.24%, 33.71%, 37.22%), protein (43.91%, 42.62%, 42.73%), lipid (14.21%, 14.62%, 6.54%), ash (12.19%, 11.05%, 12.90%), NPN (0.02%, 0.18%, 0.16%), TPC (1.02x10°, 1.96x10° and 1.96x10° CFU/g) respectively. Lower levels of protein, lipid, and ash content in the product obtained from collected samples were probably related to the losses occurring at different stages of the marketing chain during handling, transportation, and preservation. Higher moisture content along with higher microbial load was found in the collected samples than the control sample.

Amino acid of collected and prepared shidhal were analyzed by HPLC and the highest percentages of total amino acids composition of laboratory-prepared shidhal, sample collected from Narsingdi and Mymensingh were serine (3.25%, 3.46%, 11.35%), proline (1.59%, 0.94%, 0.002%), Phenylalanine (0.54%, 0.72%, 0.79%), Methionine (1.79%, 0.12%, 1.51%) respectively. The present study concludes that the overall nutritional and safety aspects of LPS were much higher than the sample collected from shidhal farmers indicating a lack of proper hygiene and safety measures.