Production of a Semi Ready-to-Eat Shrimp Soup Powder and Assessment of Its Shelf Life

  Macrobrachium nipponense are wetland crustaceans. The shrimp is rich in protein and unsaturated fatty acids (FAs). Therefore, the aim of this study was to use M. nipponense as a supplement for the preparation of a new soup. Nearly 40 kg of M. nipponense were harvested from Anzali Lagoon, Northern Iran. Shrimps were washed and dipped in NaCl solution (10% w/v) with a ratio of 1 to 2 at boiling temperature for 3 min. Then, these were cooled down for 10 minutes and dried by a cabinet-type air dryer at 70 ◦C ‎for 6 h. Dried meats of shrimps were crushed using grinder. Nearly 4% of the crushes were combined with other ingreadients of the shrimp soup. Each 100 g of the soup powder was packed in a metalized film under vacuum and stored at room temperature for 6 months of storage. Results have shown that dried shrimp meats include useful compositions such as saturated FAs (ΣSFA; 33.36 ±2.5%), monounsaturated FAs (ΣMUFA; 21±1.6%) and polyunsaturated FAs (ΣPUFA; 38.92 ±2.1%). The protein content in dried shrimp meats was high (72.74 ±1.99% of dry weight). Chemical parameters of the samples such as thiobarbituric acid (TBA), peroxide value (PV), total volatile base nitrogen (TVB-N) and free fatty acid (FFA) increased and quality of the packaged soup color decreased with increased storage time (P < 0.05). The sensory evaluation (color, odor, flavor/taste and texture) of the samples has shown that these parameters are more acceptable during the first month of storage than other months. The total number of bacteria and fungi was respectively calculated as 4.1 and 3.79 cfu/g of sample during 6 months of storage. In this study, use of 4% of the dried shrimp meats as supplement made a great taste in the soup. Furthermore, appropriate packaging under vacuum and use of metalized polyethylene films increased the shelf-life of the soup powder.