Nowadays, obtaining optimal-looking, ready-to-eat, juicy stone fruit is a challenge for consumers. A huge amount of work in genetic improvement has been carried out in recent years, especially with peaches and nectarines, resulting in new, more resistant and productive early varieties, but with losses in organoleptic quality, which has led to a drop in the demand.
Moreover, access to markets in which consumers demand ready-to-eat fruits entails the application of preservation-ripening protocols based on the time-temperature binomial, which do not always lead to the expected results. One of the main sensory attributes identified as deficient in these new stone fruits is the juiciness; a property that plays a very important role in the acceptance of the product by consumers.
Consequently, researchers from the Higher Technical School of Agronomic, Food and Biosystems Engineering (ETSIAAB) of the Polytechnic University of Madrid (UPM), working in partnership with the company Frutas Esther, have designed and implemented an instrumental procedure based on optical properties and mechanics to objectively evaluate the juiciness of peaches and nectarines. This study will allow market shelves to be filled with juicy, optimal-looking and ready-to-eat products.
Through tests in which they have studied more than 3,000 pieces of 20 different peach and nectarine varieties, they have confirmed the independence between the product's water content and its organoleptic juiciness, confirming that juiciness is a textural attribute. Also, a protocol has been developed for the categorization by juiciness of peaches and nectarines, making it possible to objectively identify those batches with optimum organoleptic quality.
In the opinion of Belén Diezma, researcher in charge of the study, “the adoption of this procedure by all links in the stone fruit value chain will facilitate commercial relations between them and ensure the meeting of consumer expectations, especially of those willing to pay more for ready to eat products.” Furthermore, a categorization of fruit juiciness is currently underway using non-destructive spectroscopic procedures.