The Effect of Salting Conditions on Formation of Cholesterol and Cholesterol Oxides During Gulbi Processing and Storage

Cholesterol and cholesterol oxide products (COPs) of Gulbi (Pseudosciaena manchurica) processed and stored at different salting times of 5 hours and 5 days were analyzed. The content of cholesterol was $133.4{\pm}5.20\;mg/100\;g$ in the fresh sample. Cholesterol content was decreased during salting and storage; its contents were $130.3{\pm}2.95\;mg/100\;g$ and $87.2{\pm}3.49\;mg/100\;g$ in 5 hours and 5 days salting samples, respectively. The content of 7-ketocholesterol in 5 hours and 5 days salting samples were $75.2{\pm}2.70\;{\mu}g/100\;g$ and $82.4{\pm}3.30\;{\mu}g/100\;g$. The 7-ketocholesterol content of salting sample for 5 hours had no significantly difference for 2 days sun drying, but it was dramatically increased during 5 days sun drying and then increased during storage days. $7{\alpha}-$ and $7{\beta}-hydroxycholesterol$ were not detected in fresh sample, but increased during Gulbi processing and storage. The $7{\alpha}-hydroxycholesterol$ was increased during Gulbi processing and storage and a higher level of $658.1{\pm}6.20\;{\mu}g/100\;g$ was detected in 5 hours salting sample than in 5 days salting sample after 21 days storage. The $7{\beta}-hydroxycholesterol$ also showed similar tendency with $7{\alpha}-hydroxycholesterol$; it was largely increased between 7 and 14 days storage in 5 days salting sample.

염장조건이 굴비 가공 중 콜레스테롤 및 콜레스테롤 산화물 생성에 미치는 영향

굴비 가공 중 식염농도가 콜레스테롤 산화에 미치는 영향을 분석하고자 염장시간을 5시간과 5일로 달리하여 건조 저장한 후 콜레스테롤 및 그 산화물의 함량을 분석하였다. 생 시료의 콜레스테롤 함량은 $133.4{\pm}5.20\;mg/100\;g$으로 정량되었으나 천일염으로 염장 후 콜레스테롤 함량은 5시간 염장하였을 때 $130.3{\pm}2.95\;mg/100\;g$, 5일간 염장한 시료에서 $87.2{\pm}3.49\;mg/100\;g$으로 염장시간에 따른 콜레스테롤의 감소가 현저하였으며 저장기간 동안 콜레스테롤의 함량은 점차 감소하였다. 7-ketocholesterol은 5시간 및 5일간 염장 후 각각 $75.2{\pm}2.70\;{\mu}g/100\;g$과 $82.4{\pm}3.30\;{\mu}g/100\;g$으로 정량되었다. 5시간 염장시료는 건조 2일까지는 7-ketocholesterol의 함량에 유의차가 없었으나 건조 5일에 급격히 증가하였고, 저장기간 동안에도 점차 증가하였다. $7{\alpha}$ 및 $7{\beta}-hydroxycholesterol$은 생 시료에서는 전혀 검출되지 않았으나 가공과정을 거치면서 점차 증가하였는데 $7{\alpha}-hydroxycholesterol$의 함량은 저장 21일 후는 5시간 염장한 시료($658.1{\pm}6.20\;{\mu}g/100\;g$)에서 5일간 염장한 시료($539.6{\pm}6.17\;{\mu}g/100\;g$)보다 $118.5\;{\mu}g/100g$ 더 많이 생성되었다. $7{\beta}-hydroxycholesterol$도 염장 및 저장 기간에 따라 그 함량이 증가하였으며 5일간 염장한 시료에서는 저장 7일과 14일 사이에 증가폭이 가장 컸다.