천연 추출물을 이용한 참치 적색육의 변색 방지 및 반응표면분석법을 이용한 최적화

Abstract

The red color of tuna is a crucial qualitative element impacting customer purchasing decisions. Its color is determined by the heme protein, myoglobin, found in the muscle cells. Oxidation of red-colored oxy myoglobin (oxy-Mb) and deoxy myoglobin (deoxy-Mb) leads to the formation of brown-colored met myoglobin (met-Mb) due to various factors, including enzymatic reactions. Notably, the color variation is not an indicator of fish freshness or seafood quality. Since oxidation is a primary mechanism leading to met-Mb formation, this study aimed to explore the potential of natural antioxidants in extending or delaying color change. As a preliminary investigation, the antioxidant activity, total phenolic content, and total flavonoid content of selacted natural plant and seaweed extracts, namely mulberry (Morus alba), prickly pear cactus (Opuntia ficus-indica), rosemary (Rosmarinus officinalis), lavender (Lavandula angustifolia), liquorice (Glycyrrhiza glabra), sambaekcho (Saururus chinensis), eoseongcho (Houttuynia cordata), and kelp (Saccharina japonica), were determined. Among them, the rosemary extract exhibited the highest antioxidant activity and was consequently selected for additional research. Optimal conditions were determined using response surface methodology (RSM) to prevent the discoloration of tuna using rosemary extract. The RSM model exhibited a statistically significant correlation. The optimal immersion conditions were found in an extract concentration of 0.0152 mg/mL, an immersion time of 15 seconds, and an immersion rate of 1:2.93. Following that, the quality changes of tuna with the optimal conditions on the microbiological, chemical, and sensory characteristics were assessed during the storage. The experimental group treated with rosemary extract demonstrated significantly improved quality compared to both the negative control group (not treated samples) and the positive control group (treated samples with 250 ppm L-ascorbic acid). This study demonstrates that the natural antioxidant capabilities of rosemary extract can effectively prevent discoloration in red muscle fish-meat when used under the right conditions.