Identification of Discriminator Formaldehyde Source in Moonfish (Lampris guttatus) Based on Total Plate Count and Quality Deterioration Parameters

Abstract

The opah fish (Lampris guttatus) is one of the fish species included in the by-catch (HTS) that has high economic value. However, it contains high levels of natural formaldehyde, which presents a challenge in detecting the addition of artificial formalin in opah fish. This is because the detection of formaldehyde in fish is total formaldehyde, which consists of natural formaldehyde and added synthetic formaldehyde. Natural spoilage of fish can result in the formation of formaldehyde through the enzymatic reduction of trimethylamine oxide (TMAO), leading to the formation of by-products such as dimethylamine (DMA). The formation process can also be influenced by bacteria, leading to a faster deterioration process. This study investigated typical indicators of cold storage in moon fish with and without artificial formadehyde application for two weeks. The study observed various parameters, including total plate count, pH level, total volatile base (TVB), formaldehyde (FA), and dimethylamine (DMA). The results showed that Total Plate Count (TPC), FA, and TVB levels can be utilized as discriminator factors between fish that have been treated or not treated with artificial formaldehyde.