Recent Advance in Aromatic Volatile Research in Tomato Fruit: The Metabolisms and Regulations

Aroma, an essential characteristic of tomato fruit, plays an important role in determining the perception and acceptability of tomato products by consumers. During tomato fruit ripening, associated with color changes from green to red involving the conversion of chloroplasts to chromoplasts are changes of aromatic volatile profiles. Although the biosynthetic pathways for some aromatic volatiles have been established in tomato fruit recently, our knowledge of regulatory mechanisms is still rudimentary. On the other hand, many internal and external factors modify volatile metabolism in tomato fruit. This review first summarizes the current knowledge of expression patterns and biosynthetic pathways of aromatic volatiles in tomato fruit along with the role of ethylene in their biosynthesis. The impact of internal and pre- and postharvest external factors on volatile composition is then discussed. This review will provide critical information for research on tomato aromatic volatiles and their manipulation.