Fish Freshness Sensing Using Changes in Eye Fluid Fluorescent Compounds of Tilapia (Oreochromis nilotica)

Abstract

Ensuring the freshness of fish is crucial for determining its quality, influencing its appearance, and attracting consumers. Identifying spoiled fish in the early stages of spoilage is challenging for many consumers, necessitating the development of effective fish freshness evaluation methods. This study proposes the development of a fish freshness evaluation sensor applicable to farmers, wholesalers, and retailers in the tilapia fish value chain. The research focuses on determining the rate of change of fluorescent compounds in fish eye fluid and establishing the relationship between these changes and fish storage. High-performance liquid chromatography (HPLC) is employed for the identification of retinol (vitamin A) and pyridoxine (vitamin B6) in the eye fluid at different storage stages. The study also uses an ultraviolet/visible light spectrophotometer to measure the emissions of fluorescent compounds during various storage periods. The acquired data is utilized to validate the sensor, which integrates a microprocessor, spectroscopy sensor, and power source. The performance evaluation aims to establish the sensor's effectiveness in detecting changes in fluorescent compounds across different stages of fish storage. The results show that the concentration of retinol increased gradually and then reduces while that of the pyridoxine reduces to zero hence providing a valuable insight into a tool that can be applied throughout the tilapia fish value chain. This innovation could greatly enhance quality control processes in the seafood industry. Unlike traditional sensory evaluations, the sensor-based method boasts notable benefits, including greater objectivity and the capability for real-time assessments.