Improving the Taste of Tomatoes Using GC-MS

The preservation of food at home is a major concern for all consumers. A group of researchers from INRA in Avignon, France, have conducted a study into tomato aroma with the aim of finding the optimum conditions for storage. According to results published in Food Chemistry,¹ the team used gas chromatography coupled to mass spectrometry (GC–MS) tomeasure volatile compounds in the fruit.

Tomatoes are commonly mentioned in consumer complaints and this was a key factor in the choice of food tested. The team chose two types of plants, Levovil, which is characterized by large fruit and pharmaceutical sensory attributes, and LCx, which is noted for aroma intensity, and two different storage modes — 4 °C and 20 °C — for the analysis.

The team analysed volatile compounds extracted from the tomatoes after they had been stored at the different temperatures. The samples were injected into a GC–MS system and a total of 44 volatile compounds were found. Storing tomatoes at 4 °C in the refrigerator saw a drastic loss in volatiles; after 30 days the concentration of volatiles had decreased by 66%. However, if the tomatoes were stored for less than a week in the fridge the aroma could be re‑established by storing them for 24 h at room temperature. Even at over two weeks there were still some positive effects that could besalvaged. Contrarily, storing tomatoes at 20 °C increased volatile production and therefore aroma profile.

Corresponding author of the study Catherine Renard told The Column: “Tomatoes are a valuable source of nutrients.Taste is an important driver for tomato consumption, but consumers increasingly complain about lack of taste of fresh tomatoes. We have shown that consumers could themselves have an impact on tomato taste, by assessing the volatile compounds responsible for tomato aroma. Storing tomatoes in the refrigerator means a rapid loss of flavour: Concentrations of volatile compounds and their equilibrium changes, so that the flavour note is affected.

In contrast, production of volatile compounds increases when tomatoes are stored at room temperature, and specially those originating from carotenoid catabolism with floral notes.” Renard added: “Consumers also have a responsibility in the loss of flavour of tomatoes. They can avoid it by storing at room temperature, or enhance it by storage in the refrigerator. A simple gesture for more summer pleasure!” The study concluded that consumer guidelines could be beneficial to ensure that tomatoes are enjoyed at their full potential.

Reference

1. Catherine M.G.C Renard et al., Food Chemistry 139, 825–836 (2013).