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. Accordingto 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. Theteam chose two types of plants, Levovil, which is characterized by large fruit and pharmaceutical sensory attributes, andLCx, 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 differenttemperatures. The samples were injected into a GC–MS system and a total of 44 volatile compounds were found. Storingtomatoes at 4 °C in the refrigerator saw a drastic loss in volatiles; after 30 days the concentration of volatiles had decreasedby 66%. However, if the tomatoes were stored for less than a week in the fridge the aroma could be re‑established bystoring 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 freshtomatoes. We have shown that consumers could themselves have an impact on tomato taste, byassessing the volatile compounds responsible for tomato aroma.Storing tomatoes in the refrigerator means a rapid loss of flavour: Concentrations ofvolatile compounds and their equilibrium changes, so that the flavour note is affected.

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

Reference

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

This story originally appeared in The Column. Click here to view that issue.