Background
Pyrazines are used in food industry to impart the foods nutty-roasted flavor. However, their extraction from natural sources is difficult and expensive. At the same time, there is awareness against the chemical food additives. Microorganisms are approved as natural producers of flavors. The
Conclusions
The results of the present study revealed the potential ability of Tolypocladium inflatum SRH81, that was isolated from Egyptian soil, to produce pyrazines having roasted- nutty aroma.
Results
The selected fungus was identified as Tolypocladium inflatum SRH81. A high correlation was found between the consumed sugar and dry matter content of each culture. Incubation of the fungus culture enriched with 0.5 g amino acids/50 mL medium for 12 days at pH 8 showed the highest generation of pyrazines and best odor sensory quality. Nine pyrazines were identified among them 2-methylpyrazine was the major compound after incubation for 12 days. A positive correlation was found between the total pyrazines and intensity of roasty-nutty aroma. Encapsulation gave rise to a significant decrease in the total volatiles, while the odor intensity showed insignificant decrease. Conclusions: The results of the present study revealed the potential ability of Tolypocladium inflatum SRH81, that was isolated from Egyptian soil, to produce pyrazines having roasted- nutty aroma.