市中에 流通되는 튀김용 油脂의 性狀에 對한 調査硏究 = A Study for the Physiochemical Properties of Frying Oil Used at Snack Corners

다국어 초록 (Multilingual Abstract)

Fried foods are characterized by high calories and high content of fat soluble vitamins. So, the rancidity of frying oil is very important in determining nutritive value of fried foods.
This investigation was carried out on four kinds of frying oil being used at scattered snack corners in Seoul, and the acid value peroxide value, refractive index, and color index of them were measured. The experiment at laboratory was performed under the similar condition as that of most snack corners in Seoul, and the change of physiochemical properties were checked every 30 minutes.
The results are summarized as follows;
1. The most used frying oil were shortening (41.2%) and rice bran oil, followed by soy bean oil and rapeseed oil. The rancidity of all kinds of frying oil used at snack corners was found to be almost the same (α=0.05).
2. When the oil is heated in 180℃±5℃ for 180 minutes, the peroxide value and acid value have increased gradually as shown in Table 2 and 4.
3. Acid value, peroxide value, refractive index, and color index of each frying oil showed a tendency of increasing in proportion to frying time in all cases, and the increasing rate is the highest in first 30 minutes.
4. The acid value of all the frying ail at snack corners was estimated at AV 2.56 on average, which exceeds the allowable level by the Regulation of Food Sanitation.
5. Although peroxide values were almost invariably under POV 30 (98.8%), no serious problem may arise because of the high values of color index, refractive index and acid value.