Measuring the taste of a tomato with an iPhone

Measure the taste without tasting. For tomatoes this has been possible for decades with the taste model developed by Wageningen University & Research. This model makes judging the taste much easier than with a panel, but it is still fairly cumbersome. For a current taste measurement with the model, a minimum of 3 kilograms of tomatoes must be turned inside out in a laboratory. The latest sensors offer opportunities to make this a lot faster and easier. And maybe even with an iPhone!

The taste panels of Wageningen University & Research are well known: a consumer panel and product-specific sensory panels that assess the taste of different products. Based on the knowledge of these panels, WUR developed taste models for a number of products. Those models work, but wouldn't it be nice to do a measurement yourself in the greenhouse or shed on a single fruit?

The soon to be launched Fresh on Demand project is working on improving quality in the fruit and vegetable chain, for a better alignment with the wishes of consumers. Taste is an important part of this. That is why within Fresh on Demand it is being investigated whether taste can also be measured with non-invasive sensors. In practice, only the brix content (the amount of dissolved sugars) is often measured as 'fast' taste measurement. But taste is more than just the sweetness of a tomato.

That is why WUR is looking into a selection of non-invasive sensors this year, including VIS / NIR Hyperspectral Imaging & Transmission Spectroscopy, various handheld sensors and TeraHertz. The aim is to develop a new taste model with the help of these sensors to measure the taste. That is simpler and therefore cheaper than with the current taste model and faster and more complete than with just a brix measurement.

The user-friendliness follows from the fact that the sensors are 'non-invasive': the tomatoes are tested from the outside, so they do not have to be destroyed. This makes it possible to perform taste research already in the greenhouse of, for example, a breeder. In addition, a number of the sensors to be investigated are already built into some smartphones.

Fresh on Demand is a public-private partnership of, among others, breeders, technical companies, trading companies and growing companies and is co-financed by Topsector Tuinbouw & Uitgangsmaterialen. The goal of Fresh on Demand is to optimally align fruit and vegetable chains to consumer wishes and requirements so that the consumption of fruit and vegetables increases.