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Real beef soup samples were separately supplemented with 5-nucleotides extracted from mushroom before and after extraction of soluble sugars (NM and NMs, respectively) and yeast extract. Headspace volatiles and flavour palatability of each sample were compared with beef soup supplemented with 5-IMP and control sample. Each investigated enhancer revealed significant release of thiol-containing compounds. 3-Mercapto-2-butanone was the major identified compound in the headspace volatiles of all samples. However, the sample supplemented with 5-IMP + NM showed the highest release of this compound followed by S-NM compared with other samples. The high palatability of sample S-NM may be correlated to the high content of 2-methyl-3-furanthiol.ARTICLE HISTORY

The main objective of the present study was to evaluate the release of aroma compounds from a banana soft drink complex model system in comparison with their release from simple model systems, each contains individual food ingredients. The effect of different food ingredients (sweeteners and thickeners at different concentrations), used in formulation of the soft drinks, on flavor release from simple model systems containing banana flavor was evaluated separately. The optimum release of isoamyl acetate (the most potent odorant of banana aroma) was observed at a concentration of 10% of each investigated sweetener (sucrose, glucose, and corn syrup). Pectin and xanthane showed the highest release at a concentration of 2.5 and 0.8% w/w, respectively. The level of each ingredient that showed the optimum release of isoamyl acetate was selected and used in formulation of a banana soft drink complex model system. The released volatiles were trapped by tenax and activated carbon. The gas chromatographicmass spectrometric analysis revealed a gradual decrease (p < 0.05) in the volatile compounds release from the complex banana soft drink model system during storage for 90 days. However, the total content of the volatiles adsorbed by activated carbon trap was higher than that trapped by tenax. The percentage of isoamyl acetate to total volatiles (isoamyl acetate/total volatiles %) was calculated for each sample during storage. A distinct linear correlation was found between the calculated values and storage time (r = 0.97 and 0.92 for volatiles trapped by tenax and activated carbon, respectively). Sample stored for 60 days showed the highest value. These findings confirmed the results of aroma sensory evaluation.

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The feasibility of using Isomalt “the food grade substance” as electron paramagnetic resonance (EPR) material in monitoring the absorbed dose has been studied. Isomalt was prepared in two forms (powder and rods). The sensitivity of Isomalt to gamma rays exceeded by increasing the absorbed dose. The prepared powder can be used in monitoring the absorbed dose in the dose range up to 22 kGy, whereas the rods can be used in the range from 5 to 50 kGy (almost double the allowed powder range). After irradiation two signals were recorded using the EPR technique addressed as S1 and S2 with (g) factor valued by 2.01 ± 0.002 and 1.993 ± 0.002 respectively. This dosimeter offers negligible humidity effect during irradiation, short and long term stabilities were investigated as well. The obtained results may qualify the Isomalt substance to be used as dose monitoring in low and moderate irradiation doses.

plastic film consisting of poly vinyl alcohol (PVA) and P H indicator dye, Orange IV, in the presence of chloral hydrate was prepared and formed by simple casting technique. Studying its dosimetric behavior was executed to approve the possibility of its usage in dose monitoring, the data obtained reveal that the intensity of the absorption band at 448 nm was decreased with the increase of the absorbed dose in a systematic manner that covers a range that reaches up to 100 kGy. On visual investigation, the film changes its color from yellow to red passing through the orange color upon exposure to gamma rays. The response of the prepared films depends on both chloral hydrate and dye concentrations. Increase in recording values was noticed on increasing the concentrations of both the chloral .hydrate and dye. Although the film has a good stability in relative humidity ranging from 10% to 50% , correction should be done out of this addressed range. The film also has excellent stability before and after irradiation in different storage environments.