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[Display omitted] • Variety and break process affect puree viscosity without specific rheological signatures. • Impacts of variety and break process can be differentiated by sensory analysis. • Structural vs soluble sugar proportions vary by cultivar. • Cold break soluble pectins are more compact and spherical than hot break pectins. • Processing method modifies aggregation between cell wall materials and lycopene. The texture of tomato products can be modified by choice of variety, their growing conditions and/or processing method, but no clear explanation exists of the mechanisms that transform fruit tissue, how they act on texture, or whether genetics and processing impact the same physical parameters. We therefore conducted a study that processed 4 varieties produced under low/high nitrogen supply, into puree using both hot and cold break processes. No specific rheological signature allows discrimination between cultivar-induced or process-induced textural changes, but that they can be distinguished by sensory analysis. Growth conditions impacted but was not sensory distinguished. Both caused significant variations in 7 of 11 physico-chemical parameters, but the order of importance of these traits controlling texture varied, depending on whether the cause was genetic or process-related. Analysis of alcohol insoluble solids revealed a specific signature in pectin composition and conformation that could be linked to particle aggregation in the presence of lycopene-rich particles. [ABSTRACT FROM AUTHOR]

The mid-infrared spectroscopy (MIRS) was investigated as a tool to improve the quality of tomato products considering its implementation at different steps along the processing chain. Models have been developed using partial least square (PLS) regression to predict the quality of raw and processed tomatoes. A relevant method (Multi-year Combining models) consisting in adding early-season tomatoes data within models developed using data of previous years, was shown as the most efficient and adapted to realistic industry conditions. MIRS predicted, in external validation, soluble solids content (R2 0.95), titratable acidity (R2 0.88) and dry matter content (R2 0.81) with a high accuracy of 0.1°Brix, 2.8 mmol H+/kg and 0.4% respectively. Secondly, MIRS was used to classify tomato products depending on processing methods (hot- or cold-break) or varieties using factorial discriminant analysis (FDA) based only on spectral data. MIRS was assessed as an efficient tool to classify processed tomato purees according to process, year and variety, more accurately than the classification obtained with the reference data. A possible implementation of MIRS was suggested at three strategic steps along the processing chain to i) characterize the incoming raw material, ii) monitor the matrix changes during processing and iii) control the final products. • Strategies are setup to build robust models to predict tomato quality traits. • MIRS allows an accurate classification of hot-break and cold-break tomato products. • An efficient implementation of MIRS along the processing chain is proposed. [ABSTRACT FROM AUTHOR]

Processing tomato is a main source of phytomicronutrients in the human diet due to its micronutrient content, and the diversity of derived products consumed worldwide. A large proportion of processing tomatoes are grown under Mediterranean climate where increasing water scarcity and heat are expected to reduce yields and to have negative impacts on fruit quality. Despite this, the effects of changes in fresh fruit quality on processing and end-product quality have been under-investigated. It therefore seems imperative to work along the food chain to improve food sustainability while maintaining quality and access to important phytonutrients. The present study adopts a holistic approach from field to processing plant, assessing the effects of reduced water and nitrogen supplies on yields, fresh fruit quality and suitability for processing, and puree quality. The 5-year trial included eight varieties, several levels of water and nitrogen supply, and two processes. It was found that water deficit induced a decrease in fresh commercial yield, partially compensated by an increase in dry matter content. The yield loss was the result of a lower number of fruits per plant, while the average fruit weight and biochemical composition showed little change. Water use efficiency decreased above 120% of water demand restoration and improved under low nitrogen supply. Puree viscosity and dry matter content increased with water deficit with beneficial effects for the industry, while the reduction of nitrogen supply did not affect puree quality. This work highlighted the possibility of monitoring quality traits in tomato puree directly from field. Nevertheless, the trade-offs between WUE, quality and yield need to be optimized. Selection of varieties rich in lycopene could be a promising avenue as they appear more tolerant to water deficit. This work also stressed the need to reassess the crop coefficient for new varieties, to improve evaluation of water needs. [Display omitted] • A large range of water regimes was applied, during a five year-trial. • Water use efficiency reached a maximum when irrigating at 120% of theoretical needs. • Moderate irrigation reduction increased fruit dry matter content and puree viscosity. • Monitor quality traits of tomato purees directly from field appeared possible. • The trade-offs between water savings, yield and puree quality need to be optimized. [ABSTRACT FROM AUTHOR]