Effects of Antioxidants on Oxidation of Tallow by Gamma Irradiation

감마선 조사시 우지 산패억제를 위한 항산화제의 첨가효과

The effects of antioxidants, ascorbyl palmitate (AP), ${\alpha}-tocopherol\;({\alpha}-Toc)$, BHA and ascorbyl $palmitate+{\alpha}-tocopherol\;(AP+{\alpha}-Toc)$ have been investigated on lipid peroxide formations in tallow immediately and during storage at $50^{\circ}C$ after gamma irradiation with the dose of $1{\sim}10kGy$. Immediately gamma irradiation greatly increased the initiative oxidation of tallow as was expected. But antioxidants were found to be greatly effective in minimizing the radiation-induced peroxidation of tallow and their antioxidative activities were $AP>BHA>AP+{\alpha}-Toc>{\alpha}-Toc$. Especially, AP showed greater antioxidative activity of initiate-oxidation than that of any other antioxidant. Oxidation of tallow during storage at $50^{\circ}C$ after irradiation induced the accelate of autoxidation. But the additions of antioxidants inhibited formation of peroxide. Their antioxidative activities were $BHA>AP+{\alpha}-Toc>{\alpha}-Toc>AP$. Especially $AP+{\alpha}-Toc$ mixture was not significantly different from BHA (p>0.05).

우지에 항산화제로 ascorbyl palmitate (AP), ${\alpha}-tocopherol\;({\alpha}-Toc)$, BHA 및 ascorbyl $palmitate+{\alpha}-tocopherol\;(AP+{\alpha}-Toc)$을 첨가하여 $0{\sim}10\;kGy$의 선량으로 감마선을 조사하였고, 감마선 조사된 시료는 조사직후와 $50^{\circ}C$에서 저장하면서 저장기간에 따른 과산화물 형성 억제능을 측정하였다. 감마선 조사직후의 과산화물가는 감마선 조사선량의 높아짐에 따라 증가하였다. 그러나 우지에 항산화제를 첨가한 경우에는 감마선 조사에 의한 과산화물 형성을 억제하였고, 억제 활성은 $AP>BHA>AP+{\alpha}-Toc>{\alpha}-Toc$로 AP가 초기산화 억제능을 가진 천연항산화제로 나타났다. 저장기간에 따른 과산화물가는 감마선 조사에 의해 자동산화를 상당히 촉진시키지만 항산화제를 첨가한 경우에는 과산화물 형성을 유의적으로 억제하였으며, 이때의 항산화능은 $BHA>AP+{\alpha}-Toc>{\alpha}-Toc>AP$의 순으로 나타났다. 특히 저장말기까지도 효과가 높았던 천연 항산화제 혼합물인 $AP+{\alpha}-Toc$은 BHA와 유의차가 인정되지 않았다(p>0.05).