Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
6393656 | Food Control | 2012 | 5 Pages |
Canned tuna meat was inoculated with Raoultella ornithinolytica at a level of 2.0 log CFU/g (low) or 5.0 log CFU/g (high) and stored at 4, 15, 25, or 37 °C to investigate bacterial growth and formation of total volatile base nitrogen (TVBN) and histamine in canned tuna meat. R. ornithinolytica grew rapidly in all samples stored at temperature above 15 °C regardless of the inoculation levels. The histamine contents quickly increased to higher than 50 mg/100 g within 12 h in the low inoculated samples and stored at 37 °C as well as in those inoculated with the high level and stored at 25 °C or higher. However, growth of R. ornithinolytica and its histamine production were inhibited when samples were stored at 4 °C. The TVBN contents in all samples were all below 30 mg/100 g during storage even when the levels of histamine in some samples increased to greater than 50 mg/100 g. Therefore, canned tuna meat was a good substrate for histamine formation by bacterial histidine decarboxylation at elevated temperatures (> 15 °C) when it is contaminated with R. ornithinolytica.
⺠Hazardous level of histamine be formed by R. ornithinolytica in canned tuna at >15 °C. ⺠Histamine formation of R. ornithinolytica in canned tuna was controlled at 4 °C. ⺠Use of TVBN as an indicator to predict histamine contents and risk should be avoid.