Canned tuna accounts for approximately 80% of the tuna consumption market. In Korea, skipjack tuna is widely used for canned tuna; however, its high histidine content can lead to histamine formation during processing. Histamine poses a risk of scombro...
Canned tuna accounts for approximately 80% of the tuna consumption market. In Korea, skipjack tuna is widely used for canned tuna; however, its high histidine content can lead to histamine formation during processing. Histamine poses a risk of scombroid poisoning and, once formed, is difficult to eliminate by heat treatment, underscoring the need for preventive approaches. Therefore, this study aimed to propose a standardized processing flow to suppress histamine formation by modeling key factors in canned tuna manufacture, including sorting- related issues (over-thawing and insufficient precooking), holding, cross-contamination, and environmental conditions (temperature and humidity). The results showed that over-thawing posed a low risk of histamine formation, even during high-temperature holding, because no external contamination occurred. In contrast, insufficient precooking increased the risk of histamine formation during high-temperature holding due to residual microorganisms. Notably, the proportion of histamine-forming bacteria had a greater impact on histamine accumulation than a simple increase in total bacterial counts. In addition, histamine levels increased rapidly when products were held under high-temperature and high- humidity conditions after cross-contamination; however, histamine formation decreased when either temperature or humidity was controlled under otherwise identical conditions. Additionally, simultaneous control of cross-contamination and humidity reduced the proportion of histamine- forming bacteria, inhibited histidine decarboxylase activity, and suppressed histamine formation. Ultrasound treatment further reduced histamine production by more than 60%. In conclusion, this study confirmed that cross-contamination during processing and high- temperature/high-humidity conditions caused by steam from the precooking step contribute to histamine formation in canned tuna. By introducing humidity management as an additional control criterion to conventional FDA approaches that primarily limit temperature and time, and by proposing an ultrasound-based mitigation strategy, this study optimized processing conditions to improve histamine control in canned tuna.