餐飲業油炸油品質調查與影響因子分析-以中部醫院及美食街為例

本實驗主要調查臺灣中部地區醫院團膳及美食街業者，分別記錄所取油炸油之油炸條件，並檢測總極性化合物、酸價、過氧化價以及使用感官品評法評估油脂色澤與油耗味，並分析油炸條件與前列數據以及各數據間之相關性。最終以此數據，提供業者及衛生單位進行參考。　　油炸條件與相關指標中發現，新舊油混合之油炸油油炸前後差值，會比使用新鮮油脂油炸來的高。另兩段式油炸中，第一段與第二段的油樣數值並無差異，可能因第二段時間較短(<1分鐘)導致。但二段式油炸的油脂酸價較高於其餘樣品，可能與該食品皆為裹粉之肉品有關。整體發現，油脂使用量與油炸食品量比值(oil-food rato, OFR)較小時油脂之油炸前後差值(ΔTPC, ΔAV, ΔPOV)較高，但比值的影響會因店家換油頻率高、持續油炸時間低有所降低，或受到該次油炸食品特性影響。業者可根據OFR值、油炸時間與油炸食品特性，決定更換油炸油的時間，以確保油脂品質及衛生安全。　　相關性結果顯示，過氧化價與其餘參數間相關係數(r)大致<0.5，可能因其檢測標定物較為不同；酸價部分，傳統滴定方法與油質儀(DOM24)僅中度相關(r=0.549)，與酸價試紙雖為高度相關(r=0.800)但準確度較低；感官品評中油脂色澤與多數參數為高度正相關(r>0.7)，建議若有適當的訓練及規範，可將色澤納入油脂品質管理方式，提高管理效率。　　整體而言，各場域油炸後總極性化合物皆在法規合格(＜25 %)的範圍內，並無超標情形，但樣品中有8項酸價超過我國舊的油炸油標準(> 2 mg KOH/g)，且大部份樣品油炸後過氧化價皆>10 mEq/kg，顯示炸後油品多已明顯劣化現象，是否適合再用，值得再深入評估。

This study mainly investigated the hospitals group meal and food plaza in central Taiwan. The research method is first recording the frying conditions of the frying oil, second detecting the total polar compounds, acid value and peroxide value, third using sensory evaluation to evaluate the color and oil consumption of the frying oil, then analyzing the correlation between the frying conditions and the previous data and the correlation between the cross-references between the data. Finally, this data conclusion is provided for reference by industry and government agencies.The study found that all of the difference between the data before and after, the frying oil after mixture of old and new oil is higher than that with fresh oil. In the oil samples for 2nd-stage deep frying, there is no difference between the first stage and the second stage. Which is due to the short duration of the second stage (<1 minute). However, the acid value of the two-stage frying oil was higher than the other samples. This may be related to the characteristics of the food (both of them are coating meat with flour). From all of the data, it can be found that when the oil-food ratio(OFR) is small, the difference between the data before and after the frying oil(ΔTPC, ΔAV, ΔPOV) is higher. But the influence of the oil-food ratio will be reduced due to the high frequency of frying oil changes and the low frying time, or affected by the characteristics of the deep-fried food. The industry can decide the time to replace the frying oil according to conditions such as the oil-food ratio, frying time or the food substrate to be deep-fried to ensure the quality and the hygienic safety of the frying oil.The Pearson correlation results show that the correlation coefficients (r) between peroxide value and other parameters are approximately smaller than 0.5, which due to different inspection targets. In acid value part, the traditional titration is only moderately correlated (r=0.549) with the frying oil monitor (DOM24), and that is highly correlated (r=0.800) with the low range oil quality test strips but the accuracy is low. The correlation between oil color and most parameters is highly positive (r>0.7). With proper training and standard, color can be included in the oil quality management method to improve management efficiency. A summary of the dete, the total polar compounds of frying oil are within the range of qualified regulations (<25%), and there is no case of exceeding the standard. However, 8 samples of the acid values exceed the old frying oil standard in Taiwan (>2 mg KOH/g), and the peroxide value of all oil samples after frying are greater than 10 mEq/kg. It data shows that most of the oil sample after frying have obviously deteriorated. Whether it is suitable for reuse is worth further evaluation.