A tomato's flavor is a combination of its aroma and taste. Researchers from Japan and the United States now know that the pigments in tomatoes can also influence their flavor.Researchers from University of Tsukuba have developed a method to quickly measure the tomato's pigment profile. They also used this technique to study how different varieties of tomatoes affect their taste and aroma.Combinations of various pigments are responsible for the color of tomatoes, such as carotenoids or chlorophylls. These pigments can also alter the amount of flavor-related compounds, such as sugars. This affects the taste and volatile organic compounds, (VOCs), that determine the smell. The amount of flavor-related compounds and pigments in tomato fruits changes as they ripen, but the relationship between color (green) and flavor (red) has not been established.Professor Miyako Kusano, the lead author of the study, says that "pigments like carotenoids do not taste." However, they are precursors to compounds called apocarotenoid -VOCs (AC VOCs), which produce the fruity/floral aroma of tomatoes and increase the perceptions of sweetness. These characteristics appeal to consumers.The traditional methods of measuring and identifying pigments can take a long time. So the researchers created a simple method that allows for rapid analysis of large quantities of samples. The new technique allowed the team to measure the amount of carotenoids in 157 varieties of tomatoes. They then analysed the flavor of each variety to determine the relationship between the pigments and the flavor.It was found that tomatoes with high levels of chlorophyll had high sugar levels, which contributes to their sweet taste. The fruit's carotenoid profile was also correlated with AC-VOC levels.Professor Kusano explains that the pigment profile of "Dixie Golden Giant", an orange-colored variety, was "particularly interesting." It had high AC-VOC levels, but low carotenoid content. This variety contained a lot of prolycopene, which was what explained the high ACVOC levels.Growing conditions like temperature and light can have an impact on the carotenoid content in fruit. It is possible to improve AC-VOC production by comparing the AC-VOC and pigment profiles of fruits grown in different environments. This will be beneficial for both producers and consumers.The new method, which was developed by the team at lightning speed, is an effective tool to analyze pigment concentrations in large quantities of samples. It could also be used for other fruits or vegetables.Metabolites published the article "High-throughput carotenoid profiling uncovers positive associations with sugar, apocarotenoid volatile contents in fruits of tomatoes varieties in modern or wild accessions."The "Sustainable Food Security Research Project", a grant of operational funding from The Yanmar Environmental Sustainability Support Association, Japan and The National University Corporation, funded this work. This work was also supported in part by the JSPS KAKENHI grant number 19K05711 as well as a grant from National Science Foundation (IOS 1855585). The authors declare that they have no competing interests.
