Palmer' mango cultivar is a late season variety which is greatly accepted by European consumers. However, it is common to get reports of fruit quality problems, mainly due to maturity. Thus, the objective of this study was to develop calibration models for soluble solids content (SSC) and dry matter (DM) of 'Palmer' mangoes using portable (VIS-NIR) spectrometer. Interactance spectra were obtained with a portable F-750 spectrometer in the wavelength range of 306-1140 nm, 8 nm spectrum resolution, and 4 scans averaged per spectra. Spectra were used to develop SSC and DM models using partial least square regression (PLSR) with full cross validation. The best SSC calibration model was developed using spectra pre-processed with standard normal variate (SNV), first derivative of Savitzky-Golay and window of 699-999 nm. It was observed a RMSE CV of 1.39%, with a R CV 2 of 0.87, and RPD of 2.77. Better results were observed for the DM calibration model which was built with raw spectra using the window of 699-981 nm (RMSE CV of 8.81 g kg −1 , R CV 2 of 0.84, and RPD of 2.51). Poor calibration models were obtained for firmness. The results indicated that portable VIS-NIR spectrometer can be used as a non-destructive technique to assess SSC and DM content for 'Palmer' mangoes. It is necessary to incorporate more sources of variation, to reduce RMSE values and improve robustness, especially for fruit SSC and DM prediction.

The objectives of this study was to develop partial least square (PLS) models using NIR spectroscopy for the determination of SSC and firmness in intact low chilling 'Aurora-1' peach fruit, and verify the influence of maturity stage and harvest season on the models to be developed (robustness). FT-NIR spectra were obtained as log 1/R with fruit harvested in 2013 at 3 maturity stages and in 2014. The spectra were collected on the background and blush colour skin areas of the each fruit. Model performance was evaluated based on the values of root mean square error for prediction (RMSE P) and coefficient of determination (R P 2) obtained from validation fruit set (Kennard-Stone), and prediction fruit set (2014). PCA could not group the fruit based on blush and background skin colour, maturity stages, and harvest season. The model constructed using the external validation method obtained a RMSE VE of 1.08 % with 11 latent variables (LV S) and a R VE 2 of 0.59. The prediction set, independent data, resulting in a less accurate model (RMSE P 1.04 %, R p 2 0.45 and 11 LV S). The same trend happened for determining firmness with the external validation resulting in better model with RMSE VE 9.51 N and R VE 2 of 0.40 and the prediction set with RMSE P of 13.2 N, R P 2 0.40 with 7 LV S. The NIR spectroscopy showed to be a potential analytical method to determine SSC and firmness of intact low chilling 'Aurora 1' cultivar. However, it is necessary to optimize the models in other to reduce the prediction errors. 2015 Elsevier B.V. All rights reserved.

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Guava is a climacteric fruit, extremely perishable, that has a short shelf life. Controlled atmosphere (CA) and cold storage can be used to extend guava shelf life. However, few studies have been conducted to evaluate the effects of CA storage on guavas, especially with high levels of carbon dioxide (CO 2). Therefore the objective of this study was to evaluate the quality changes of 'Pedro Sato' guava fruit during CA storage with atmospheres containing low concentrations of O 2 and increasing levels of CO 2. For that, 'Pedro Santo' guavas were stored at 12.2 • C for up to 28 days in atmospheres with low oxygen (O 2) concentration (5 kPa) and increasing level of CO 2 (1, 5, 10, 15 or 20 kPa CO 2) in order to evaluate the fruit quality changes. It was possible to identify the relationships among quality variables in response to atmosphere composition and storage duration which were related to modifications due to ripening (ratio SS/TA, TSS, RS, TA), ripening and early CO 2 injury modifications (pH, SS, chromaticity), and CO 2 injury modifications (hue angle, firmness, soluble pectin). A clear CO 2 injury occurred in fruit stored in 5 kPa O 2 + 15 kPa CO 2 and 5 kPa O 2 + 20 kPa CO 2 after 28 days at 12.2 • C, with increasing pH values and soluble pectin content, which were inversely related to fruit firmness. 'Pedro Sato' guavas should be stored in atmospheres with 5 kPa O 2 and no more than 5 kPa CO 2 in order to prevent CO 2 damage. Further investigation is necessary to identify the metabolites responsible for the onset of responses to high CO 2 in guava fruit.