A Pilot study of Histamine in Silkworm Pupae

OBJECTIVES: We evaluated the effects of storage temperature and time on the concentration of histamine and microbial growth in the silkworm pupae. MATERIALS AND METHODS: Silkworm pupae were stored at -20, 10 and 25 °C respectively. We measured histamine levels and counted bacterial colonies on the microbiological culture plates in 0, 24, 48 and 72 hours after euthanizing the silkworm pupae. RESULTS: The level of histamine in the silkworm pupae was increased when storing at 10 oC and 25 oC with the lapse of time. The histamine level has soared from 24 h to 48 h at 25 °C, which is nearly 5 times higher. Each bacterial colony was increased at 10 °C and 25 °C until 48 h and then rapidly decreased in 72 h. The highest level of bacterial colony appeared in the 48 h at 10 °C and 25 °C. CONCLUSION: This study showed that the level of histamine and microbial growth in silkworm pupae were changed by the storage temperature and time. However, the histamine level in the silkworm pupae was no cause for concern on human health.