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International audience; The quality of tomato based products greatly depends on their color and viscosity, which are influenced by the fruit capacity of modifying their properties according to the processing route. Loss of viscosity due to intrinsic pectin modifying enzymes (also called ‘fruit reactivity’) is known and used to produce either hot break (HB) purees, more viscous, or cold break (CB) ones, less viscous. Color reactivity, even if less documented, also exists as HB/CB purees differ. This fruit reactivity, although essential for quality purpose, remains almost neglected from breeders. In order to verify if reactivity could be considered as a heritable trait, we measured it through a “quick and dirty” laboratory scaled process and a systematic measurement of the loss of texture and color according to HB or CB process. The results indicated that fruits can be classified according to their capacity of being impacted by the process. For viscosity, some genotypes exhibited a strong capacity for producing highly viscous purees but also exhibited a strong fruit reactivity, indicating that their advantage may be quickly lost during the process if the first break step is not efficient enough, or in case or cold break processing. On other hand, some genotypes exhibited a very low reactivity to process. Reactivity was also greatly reduced by a low irrigation level. And finally, a parallel processing at laboratory or pilot scale indicated that the behavior of a 10‐fruits sample in microwaves was correlated to the quality observed in traditional scrapped surface tubular eating system. The color of purees was also influenced by the fruit reactivity, but the enzymatic basis for the color change seemed disconnected from the one controlling viscosity. Those results open the door for a more efficient screening of tomato varieties based not only on the fruit composition, but also on their ability to react to the process.

The project CO-FREE (2012-2016) aimed to develop strategies to replace/reduce copper use in organic, integrated and conventional farming. CO-FREE alternative test products (CTPs) were tested and integrated together with decision support systems, disease-tolerant varieties, and innovative breeding goals (ideotypes) into improved management strategies. CO-FREE focused on apple/apple scab (Venturia inaequalis), grape/downy mildew (Plasmopara viticola), and tomato and potato/late blight (Phytophthora infestans). Starting point of the project were ten CTPs with direct or indirect modes of action including Trichoderma atroviride SC1 and protein extract SCNB, Lysobacter spp., yeast-based derivatives, Cladosporium cladosporioides H39, the oligosaccharidic complex COS-OGA, Aneurinibacillus migulanus and Xenorhabdus bovienii, sage (Salvia officinalis) extract, liquorice (Glycyrrhiza glabra) extract, PLEX- and seaweed plant extracts. As the project progressed, further promising CTPs were included by the partners. Field trials were performed in different European countries in 2012-2015 following EPPO standards. In the first years, stand-alone applications of CTPs were tested. In the following years these were integrated into complete strategies. Effects on main and further diseases, on yield and on non-target organisms were assessed. Here, field trial results with CTPs are summarized.

Quality control of raw tomatoes in industry is still mainly based on visual screening (for colour and fruit decay) and soluble solids content (SSC). Our current studies aimed at assessing the accuracy of mid-infrared (MIR) spectroscopy as a rapid and convenient tool to predict quality traits for the tomato industry. First, we assessed the ability of MIR to predict not only SSC, but also other biochemical traits of raw tomatoes. Therefore, MIR spectroscopy (4000-650 cm(-1)) coupled with chemometrics using partial least squares (PLS) was correlated with classical measurements, and its potential was assessed by calculating the coefficient of determination (R-2) and the root-mean-square error of cross-validation (RMSECV). Using a wide sampling strategy considering cultivars, ripening stages (from mid to overripe), two production areas (south-west and south-east of France) and irrigation practices, we showed a good ability to estimate not only SSC (error of 3.5%), titratable acidity (TA) (4.4%) and dry matter (4.3%), but also individual sugars (glucose, 4.7%, and fructose, 7%) and citric acid (7%) in fresh tomato purees. For malic acid, the higher error of prediction (14%) was probably related to its low level in tomatoes. Second, we evaluated the ability of MIR spectroscopy to discriminate cooked samples according to the origin of the raw material (varieties, maturity stages, production area) and to processing methods (discrimination between hot-break (HB) and cold-break (CB) samples). Therefore, tomatoes harvested in 2015 were processed using standard HB or CB modes, and then analysed using MIR spectroscopy. Multivariate analyses allow for clear discrimination between processing methods, production area and cultivars. This study indicates that MIR spectroscopy allows for 1) a considerable gain in analysis time compared with current methods, and 2) a prediction of a more detailed description of quality parameters than only global measurements such as SSC or dry matter. MIR spectroscopy could be developed as an efficient tool for quality control of raw material, as is already the case for other food industries, and might also be developed for quality control of processed products.

International audience; Quality control of raw tomatoes in industry is still mainly based on visual screening (for colour and fruit decay) and soluble solids content (SSC). Our current studies aimed at assessing the accuracy of mid-infrared (MIR) spectroscopy as a rapid and convenient tool to predict quality traits for the tomato industry. First, we assessed the ability of MIR to predict not only SSC, but also other biochemical traits of raw tomatoes. Therefore, MIR spectroscopy (4000-650 cm(-1)) coupled with chemometrics using partial least squares (PLS) was correlated with classical measurements, and its potential was assessed by calculating the coefficient of determination (R-2) and the root-mean-square error of cross-validation (RMSECV). Using a wide sampling strategy considering cultivars, ripening stages (from mid to overripe), two production areas (south-west and south-east of France) and irrigation practices, we showed a good ability to estimate not only SSC (error of 3.5%), titratable acidity (TA) (4.4%) and dry matter (4.3%), but also individual sugars (glucose, 4.7%, and fructose, 7%) and citric acid (7%) in fresh tomato purees. For malic acid, the higher error of prediction (14%) was probably related to its low level in tomatoes. Second, we evaluated the ability of MIR spectroscopy to discriminate cooked samples according to the origin of the raw material (varieties, maturity stages, production area) and to processing methods (discrimination between hot-break (HB) and cold-break (CB) samples). Therefore, tomatoes harvested in 2015 were processed using standard HB or CB modes, and then analysed using MIR spectroscopy. Multivariate analyses allow for clear discrimination between processing methods, production area and cultivars. This study indicates that MIR spectroscopy allows for 1) a considerable gain in analysis time compared with current methods, and 2) a prediction of a more detailed description of quality parameters than only global measurements such as SSC or dry matter. MIR spectroscopy could be developed as an efficient tool for quality control of raw material, as is already the case for other food industries, and might also be developed for quality control of processed products.