Novel Detection Techniques for Shrimp Powder Adulteration Using Near Infrared Spectroscopy in Tandem Chemometric Tools and Multiple Spectral Preprocessing

Shrimp is a common seafood that is often processed into culinary powder by using only the abdomen of the shrimp. Some producers are, however, suspected to produce the powder using immature shrimps which are illegal to fish, while some include the head regardless of standard procedures that the thorax (head) and other parts may contain sharp stones and objects that can be hazardous upon consumption. Methods for detecting such adulteration are technical, expensive, and time-consuming. Near infrared spectroscopy (NIRS) is a rapid analytical tool that can be explored for such analysis. This study aimed to develop models for detecting shrimp powder adulteration using a handheld spectrophotometer in tandem chemometrics and multiple spectral preprocessing. Using linear discriminant analysis, shrimp powder adulterated with milled immature shrimps at 0, 5, 10, 20, 30, 40, 50, and 100% w/w could be classified with an average cross-validation accuracy of 93.10%, while a higher average cross-validation accuracy of 98.63% was obtained for classifying milled shrimp head in shrimp powder. The models confirmed suspected fraudulent activities of shrimp powder adulteration in some Ghanaian markets. Using partial least squares regression and multiple spectral preprocessing, authentic shrimp powder was predicted with (RCV)-C-2's up to 0.996, RMSECV's lower than 1.25 g/100 g and RPD lower than 3.1. The handheld spectrophotometer brings an added advantage of remote analysis for adaptation of the developed models.