In the previous report, we isolated and purified one of tendering enzyme $quot;ficin$quot; from fig latex. In this study, various crude ficin concentrations and reaction time were employed to investigate the contents of free amino acids and other free nitrogen compounds after the treated with beef round muscle.
1. Free amino acids contents increased with the increase of temperature and time during the aging of beef at 1℃ and 8℃, and the increasing rate was remarkably high when fresh beef was treated with ficin. In the case of ficin treatment after various cooking, steaming showed the highest increase in free amino acid contents among three cooking methods such as boiling, steaming and pan broiling. The increased amounts of free amino acids in three groups-aging beef at 1℃ for 3 days, fresh beef treated with ficin(0.1%, 2hrs) and beef treated with ficin(0.1%, 2hrs) after cooking were 13%, 293% and 137% respectively. In contrast to aging group, the amount of free amino acids in other two groups treated with ficin was superiorly increased.
2. The amounts of total free nitrogen, free non-protein nitrogen and NH₃-nitrogen increased with the increase of temperature and time during the aging of beef at 1℃ and 8℃, and the increasing rate was remarkably high in fresh beef treated with ficin. In the case of ficin treatment after cooking, steaming gave larger amount of total and non-protein nitrogen than other two cooking, e.g. boiling and panbroiling. The increasing rate of nonprotein nitrogen to the total nitrogen of fresh beef treated with ficin(0.1%, 2hrs) was 75 times greater than that of aging fresh beef at 1℃ for 3 days.
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