Food chemistry and analysis and the study of food quality evaluation based on metabolome analysis. Researchers like Mabuchi have developed a number of methods for determining freshness and identifying food sources. Viable bacteria count, firmness, pH value or K values (a measure of nucleic acid-related compounds) being just a few. However, no one method is perfect or general enough to be used on all species of aquatic product. For Mabuchi a promising solution is metabolome analysis. After being harvested, all meat products, including fish, will begin to lose freshness and deteriorate. During this process various metabolites, chemical substances which are necessary for metabolism, are produced or altered. 'We hypothesised that a comprehensive analysis of these metabolites could provide clarification on the changes in the freshness of fish meat,' explains Mabuchi. Understanding the natural process of decomposition and deterioration of various food products would make the presence and quantity of certain metabolites an accurate indicator of freshness. Using naturally occurring biological molecules, or biomarkers, is also useful for identifying the source of a particular food product. Another project coming out of Mabuchi's research is the use of gas chromatography-mass spectroscopy to distinguish the different types of fish muscle types for sale in markets. Again, by relying on the presence of metabolites that are specific to different muscle types the goal is to prevent food fraud and provide accurate labelling and pricing of all products on store shelves. Going one step further, Mabuchi has used the information gathered in the studies on freshness and identity to develop a predicting model of taste for Yellowtail fish, a common Japanese fish product. 'I believe this can be used as a new method for assessing the palatability of fish meat and that it can become an index as to what ingredients, when abundant, cause people to experience a delicious sensation,' he shares. The ultimate goal of all this work is to help meet the growing demand for fish products, safely and sustainably while supporting fisherman's associations and aquatic foodstuffs companies. 'I think there is the additional advantage that we can provide consumers with opportunities to enjoy high quality fish,' adds Mabuchi.