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Hodnocení změn při dozrávání a skladování ovoce s využitím metod NIR spektroskopie
Šnurkovič, Petr
The dissertation thesis is focused on investigation of possibilities of usage NIR spectroscopy for nutritional composition of fruit and vegetables evaluation. The basic nutritional components of fruit and vegetables, methods of apples, peaches and tomatoes storage are characterized in the literary section. The history of infrared spectroscopy, present, principles and types of NIR spectroscopy analyses are described in detail. The possibilities of usage of NIR spectroscopy in food industry aimed on fruit and vegetables quality evaluation are also described in the literary section. Changes of fruit and vegetables nutritional composition during ripening are evaluated in the experimental part. Evaluated fruit and vegetables were apples (variety Rubinola), tomatoes (variety Dagmar) and peaches (variety Redhaven). Changes in the total polyphenols content, titratable acids, soluble dry matter, malic acid, ascorbic acid, citric acid, peel firmness and apple flesh firmness were evaluated. Calibration models were prepared from the gained data using the NIR spectroscopy method. The changes of stored fruits nutritional composition were evaluated using the created calibration models. Soluble dry matter, titratable acids, ascorbic acid and flesh firmness of different apple, peach and tomato varieties can be determined fast and exactly according to the data. The accuracy of models for total polyphenols and peel firmness is significantly influenced by the number of calibration standards. The accuracy of models for malic and citric acids is influenced by the concentration of these components in fruits.
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