title: [New methods for evaluation and analysis of organoleptic qualities of foods and for calculation of changes. 9. Dependence of irradiation flavor of apple juice and concentrate on the gamma radiation dose].
abstract: Various authors have defined organoleptically the concept "cooking flavour" for heat-treated apple juice and concentrate. In a similar way, the "irradiation flavour" caused by gamma radiation is defined in the present paper. It has been found that the irradiation flavour is attributable to low-boiling substances which appear already in the first fraction if the modified MICKO distillation is performed. Tetrahydrofuran (THF) has been identified as the key substance in irradiation flavour. As further evidence may be quoted the similarity of the intensity of off-flavour which was observed also by gas chromatography at the same times of retention, and the removal of the irradiation flavour by means of a THF-specific agent (mercury acetate). In connection with THF solutions added to non-irradiated apple juice, the authors employed the technique of "subjective olfactometry", using the "absolute value scale", to establish mathematical correlations between the intensity of irradiation flavour and the concentration of off-flavour products in apple juice or concentrate. The dependence of the intensity of irradiation flavour on the THF concentration and the gamma radiation dose, respectively, obeyed an exponential function. Thus, it has been possible to calculate the amounts of THF formed by radiation doses varying from 0.64 to 2.55 Mrad. Furthermore, the authors determined the minimum radiation dose for 12% apple juice and for 67% apple concentrate at which the irradiation flavour is first perceived (treshold of perception).
mesh_terms: D003037:Cobalt Radioisotopes; D004307:Dose-Response Relationship, Radiation; D005514:Food Irradiation / Q000009:adverse effects; D005638:Fruit / Q000032:analysis / Q000528:radiation effects* / Q000592:standards; D005663:Furans / Q000032:analysis*; D009812:Odorants; D011830:Radiation Effects; D013649:Taste
chemical_list: D003037:Cobalt Radioisotopes; D005663:Furans
vernacular_title: Neue Methoden der Be- und Auswertung sensorischer Eigenschaften von Lebensmitteln und der Berechnung ihrer Veränderungen. 9. Mitt. Die Abhängigkeit des Bestrahlungsgeruches im Apfelsaft und -konzentrat von der Dosis der Gamma-Bestrahlung