Detecting Recovery Oil by Its Characteristic Triglyceride Composition
QIAO Jie1, SHI Qiuna1, ZHAO Pengcheng2
1. Henan Police College, Zhengzhou 450046, China
2. China Criminal Investigation Police University, Shenyang 110845, China
Abstract
Objective To identify the recovery oil by analyzing the differences of various simulated recovery oils with high performance liquid chromatography-evaporative light scattering (HPLC-ELSD).Methods The simulated recovery oil, blended with soybean/peanut oil and animal grease, was extracted by acetone. The extract was undergone through HPLC-ELSD analysis under the conditions: C18 nonpolar column, keeping its temperature of 35˚C, being flowed with mobile phase of dichloromethane -acetonitrile (30:70 V/V) at running rate of 1.0 mL/min, and evaporative light scattering detector for gauging. The separated triglycerides were compared of their spectrums against the spectral data from various original constituent oil.Results Triglyceride composition varied greatly when pure vegetable oil mixed with animal grease.Conclusions The analysis of triglyceride components can identify the quality-inferior/adulterated vegetable oil suspected to be refined from recovered food waste.
Objective To describe the morphological feature of bio-waste oil in Raman spectrum for the discrimination of bio-waste oil from edible vegetable oil. Methods The morphology and difference in Raman spectrum for bio-waste oil and edible vegetable oil were compared and analyzed. Results In the full- and extended-range Raman spectra at the wavelength of 532 nm,there was a morphological feature of smooth bulk peak for various bio-waste oil samples which was not observed in all the samples of edible vegetable oil.The peaks of bio-waste oil samples in the first-derivative extended-range spectrum could be effectively distinguished form those of edible vegetable oil samples and the difference in the first-derivative full-range spectrum between the bio-waste oil and edible vegetable oil could be used to quantify the amount of adulterated bio-waste oil in vegetable oil. Conclusion A smooth bulk peak in Raman spectrum exists universally in the detection of various bio-waste oil samples and could be used in the detection of adulterated bio-waste oil in edible vegetable oil.
Molecular Biomedicine Laboratory, Shenzhen Municipal Center for Disease Control and Prevention, Shenzhen, Guangdong Province 518055, China
Triacylglycerols (TAGs) in edible oils (soybean, peanut, sesame) and hogwash oil were analyzed by HPLC-MS with atmospheric pressure chemical ionization (APCI). The gradient elution chromatographic separation was performed on a C-18 column using mobile phase of acetonitrile. acetone, and TAGs were monitored by APCI. MS in positive mode. 15 hogwash oils and 11 normal edible oils were analysed with the method. Five linoleoyl epoxides of trilinolein (LLL), dilinoleoyl. oleoyl glycerol (LOL), dilinoleoyl. linolenoyl glycerol (LLnL), dioleoyl. linoleoyl glycerol (OOL) in hogwash oil were detected. The discriminantion model established with partial least square discriminate analysis (PLS-DA), could distinguish the normal edible oil and the hogwash oil with an accuracy of 96. 2%. The linoleoyl epoxides of TAGs made the major distinguishing contribution for the model, and were proved as the mark components in hogwash oil different from the normal edible oil.
[Wang Shi-Cheng; Fan Jin-Shan; Wang Yan-Hong; Li Guo-Chen; Zhang Hong; Wang Ying] Chinese Acad Sci, Shenyang Key Lab Detect & Control Technol Food Sa, Inst Appl Ecol, Shenyang 110016, Peoples R China.