Determination of aquacultured whiteleg shrimp (Litopanaeus vannemei) quality using a sensory method with chemical standard references.

Background Fresh shrimp are highly perishable seafood and a reliable spoilage assessment method is necessary to ensure sufficient quality control. The current quality evaluation method by FDA/NOAA uses subjective terms "odor of decomposition" to reject shrimp shipments, which lacks reference standards to anchor the concept and can cause ambiguity. The purpose of this study was to develop chemical reference standards to assist in a more objective and consistent sensory evaluation of shrimp quality. Results Chemical references were developed and used by the descriptive panel to demonstrate the aroma quality indicators of shrimp. The most important aroma attributes describing shrimp quality changes were "salty water-like", "natto water-like", and "sour milk-like" based on the results of multiple linear regression analysis. The overall rating consistency of the key quality indicators was confirmed by trained descriptive panel that the intensity scores in two separated evaluation sessions (30 days' apart) were not significant different (p>0.05). The sensory ratings also corresponded well with presumed FDA/NOAA grades of shrimp. An untrained panel also confirmed "salty water-like" as the main indicator of freshness and "natto water-like" as the main indicator of spoilage, while the discriminative capacity was lower compared to the trained panel. Conclusion The developed chemical references of key aroma quality indicators allowed the trained and untrained panels to distinguish shrimp of different freshness levels. The results indicate the potential of using chemical references as a new evaluation tool for on-site quality inspection or industrial QA/QC of shrimp with improved objectivity and consistency. This article is protected by copyright. All rights reserved.