Modifications of the texture of tomato purees by variety selection or by processing methods result from various physico-chemical parameters

Tomato is the main horticultural crop for processing industry. Tomato puree is a source of phytonutrients such as carotenoids. Puree viscosity is a major quality trait, and industrial companies need reliable indicators of tomato fruit ability to produce viscous puree. Fruit quality is primarily assessed by measuring the soluble solid content, which is insufficient to predict puree viscosity. The choice of the variety and transformation process are the levers for action used by industrial producers to manage the final puree viscosity. The objective of our study was to define the parameters involved in puree viscosity variations induced by variety or process. An integrative approach examining viscosity from field to can, including four varieties and two processes (cold and hot break), was conducted in 2019 and 2020. Fruits were grown in an open field, and then processed into puree following industrial methods. Several structural and physico-chemical parameters, known to be involved in puree viscosity, were measured. A partial least square discriminant analysis highlighted that viscosity variations induced by the process were due to differences in cell wall material quantity, structure, and conformation, and to differences in serum viscosity. Viscosity variations induced by the varieties were due to differences in pulp volume fraction and pulp dry matter content. Microscopic observations evidenced the agglomeration of small particles that may also contribute to puree viscosity. These results provide a better understanding of the mechanisms determining puree viscosity and offer new perspectives for the development of viscosity indicators for industrials. Moreover, in a context of climate change, the knowledge of these mechanisms helps us understand how agro-environmental changes such as water deficit or temperature increase can interact and modify puree viscosity.

Miarka Sinkora won the ISHS Young Minds Award for the best oral presentation at the International Symposium on Integrative Approaches to Product Quality in Fruits and Vegetables at IHC2022 in France in August 2022.

Miarka Sinkora, INRAE, Avignon Université, UMR SQPOV, F-84000, Avignon, France, e-mail: miarka.sinkora@inrae.fr

The article is available in Chronica Horticulturae