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

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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.

Aromatic plants are rich in biologically active compounds that are act as antioxidant, antiviral and antitumor agents. There were different methods for the extraction of these bioactive compounds. Hydrodistillation (HD) is the most common method to get the essential oils. Ultrasonic and microwave pretreatments improve yields and quality of the bioactive compounds. The aim of the current study was to evaluate the effect of ultrasonic and microwave pretreatments followed by hydrodistillation (US-HD and MW-HD, respectively) on the quality of anise essential oil (EO) compared to conventional hydrodistillation (HD). Power and time of US-HD and MW-HD were optimized. Results revealed that MW-HD and US-HD, at optimum conditions, enhanced the extracted yield of EO compared with HD method, however the highest yield (3.0% w/w) was obtained at 60% of the maximum ultrasonic power for 30 min. The gas chromatography-mass spectrometry (GC-MS) analysis showed that at optimum conditions both extraction techniques improved the content of the phenylpropanoids compounds. There was direct correlation between the free radical scavenging activity of each extracted EO and its content of transanethole (the principle compound of anise EO). The principal component analysis (PCA) showed significant variations between the EO extracted by the different methods (MW-HD and US-HD) compare to HD. Finally, this study revealed that the best conditions to obtain better chemical composition and antioxidant activity of Egyptian anise EO was applying US-HD extraction at 60% of the maximum ultrasonic power for 30 min.

Background. Enzymatic hydrolyzed vegetable proteins have been recommended as safe precursors of process flavours. However, the degree of hydrolysis limits their production on an industrial scale. Nanotechnology can enhance the enzymatic hydrolysis of soybean protein. Therefore, the aim of the present study was to use the enzymatic hydrolyzed soybean protein isolate (E-SPI) nanoparticles for producing a high yield of meat-like process flavour. Material and methods. Ball milling, high-speed homogenization and ultra-sonication were used for preparation of SPI nanoparticles with average range 10-17 nm. The volatile compounds were analyzed by headspace solid phase microextraction (HS-SPME) and gas chromatography coupled with mass spectrometry (GC-MS). The odour attributes of beefy, roasty, savoury, sulphurous and overall acceptability were selected to describe the meat-like process aroma. Results. The total volatiles in the headspace of the meat-like process flavour based on SPI nanoparticles showed a higher yield compared with the untreated sample. Thiols containing compounds, especially the potent odorants of meat-like flavour, were predominant in both samples. However, their yield was significantly higher in the SPI nanoparticles sample. An agreement was found between the intensity of the attributes selected and the aroma composition of the two meat-like flavours investigated. Conclusion. The results of this study suggest that using protein nanoparticles as the main precursors of the process flavours is considered a new chance for innovation in nanoscience. Future studies will be carried out on improving the quality and quantity of vegetable protein nanoparticles that can be used as precursors of another process flavours.