INHIBITION OF BROWNING REACTIONS OCCURRING IN THE STORAGE OF DRIED OYSTER 2. Inhibitory Effect of Sodium Sulfite Treatment and the Addition of Antioxidants

건조굴 저장중의 갈변방지 2. 아황산소오다 처리 및 항산화제 효과

In the present paper, the effect of sodium sulfite treatment on tile inhibition of browning reactions occurring in the storage of dried oyster was tested and the supplementary effect of antioxidantsaddedwasalsomentioned. Dried oysters treated with sodium sulfite solutions as described in the previous paper(Lee and Choi, 1977) were stored in the bottles with silica gel bags at room temperature with or without the application of antioxidants. The ethanol solution of an antioxidant mixture(BHA, BHT, plus, synergists) was sprayed on the surface of cooked oyster before drying. The density of brown pigment was determined spectrophotometrically by measuring the absorbance at 420 and 440 nm of both fractions of pigment extract, namely chloroform-methanol and water soluble fractions, which represent the brown color developed by fat oxidation and Maillard reactions respectively. TBA value was also measured for the oxidative rancidity in oysters during the storage. It appeared from the results that the 0.5 M sodium sulfite-60minute treated samples showed better effect after 150 day storage at room temperature. Controlling tile pH of treating solutions, did not reveal so much different in inhibitory effect in the aspect of color but a more reduction of tyrosine and reducing sugar was resulted with acidic solution than with alkaline solution. The development of brown color in dried oyster seemed to be leaded rather by the oxidative rancidity of lipids than sugar-amino reactions particularly in a long-term storage since the browning of chloroform-methanol fraction progressed more rapidly than of water. soluble fraction. The application of antioxidant, therefore, could largely retard the browning of the product as appeared in the results that sodium sulfite treated oyster with addition of antioxidant kept the best color during the storage.

건조굴 가공시 생굴의 수세${\cdot}$자숙과정에서 아황산 소오다로서 처리하여 건조굴은 저장할 때 일어나는 갈변에 대한 영향을 검토하고 항산화제를 첨가한 효과를 측정한 결과를 요약하면 다음과 같다. 1. 아황산소오다의 침지농도별, 침지시간별 처리효과를 비교하면 전보에서 얻은 생굴중의 환원당과 tyrosine의 제거효과와 같이 건조굴의 저장후에도 0.5M 용액에서 6분간 침지한 후, 60분간 수세한 것의 효과가 가장 좋았다. 침지용액을 산성으로 조절하는 것도 도움이 되었다. 2. 저장중의 TBA치, 지방의 산화적 갈변 및 당아미노 반응에 의한 갈변도의 추세를 검토해 보면 지방산화적 갈변이 주도적이 였고 당-아미노반응 또한 완만하게 특속적으로 진행되고 있으며 두 반응은 서로 관련하고 있어 아황산염의 처리가 지방의 산화적 갈변에도 영향을 미치고 있다. 3. 황산화제의 첨가는 주도적인 갈변요인인 지방의 산화를 억제함은 물론, 아황산염의 처리와 항산화제처리를 병행하였을 때 효과는 상승적으로 나타나 0.5M 아황산소오다 처리와 항산화제를 병용했을 때가 가장 효과가 좋았다.