Abstract
This study aimed to throw the light on the nutritional value and quality of shell fish in addition to knowing the incipient spoilage of shellfish through definition of , evaluation of chemical composition of Litopenaeus vannamei shrimp (Total protein, Total fat, Total fiber, Humidity and ash), chemical analysis of Litopenaeus vannamei shrimp to determine its quality (pH, TVN, TBA and FFA) and evaluation of Litopenaeus vannamei shrimp quality.
The study was carried-out on Shrimp samples from Berkeit Ghalioun, Kafr El-Sheikh Governorate, Egypt. The samples was collected during the summer season of 2022. All samples were transported directly fresh to laboratory in ice box (at 5 – 10 oC), within 2 – 3 hours for examination. The collected 70 shrimp (30 shrimp fresh and 40 shrimp frozen) were examined for sensory and biochemical evaluation at different periods of the study. The bacteriological evaluation was made on fresh (30 samples at different densities 100 m2 and 200 m2 of breeding) and the 70 frozen samples.
This study concluded that, the sensory evaluation characters that includes colour, head/chest and tail , legs, shell and tentacles , eyes, dour and meat cleared that, the shrimp during its storage period that ranged from 1 to 20 days , the shrimp in agood quality conditions where its quantitative score ranged from 10 to 1 for the storage shrimp at 1 and 20 day. While, the results of constituent evaluation that includes protein %, fat %, moisture %, ash %, and the product evaluations that includes TBA %, TVBN %, pH, decreased with increasing the period of storage from 0 to 72 hours, while, the level of bacterial count (Total viable count, enterobacteriacae, coliforms, total staphylococci and staph. aureus counts increased with increasing the period of storage. Good preservation and application of good hygiene principlrs during catching improved the quality of shrimp.

Key words: Qyuality assessement- Litopenaeus vannamei - shrimp