- 著者
- Sanjeewa R. Karunathilaka Samantha Farris Magdi M. Mossoba
- 出版者
- Japan Oil Chemists' Society
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.67, no.12, pp.1501-1510, 2018 (Released:2018-12-01)
- 参考文献数
- 26
The ruling that partially hydrogenated oils (PHO) are no longer “generally recognized as safe (GRAS),” has accelerated the replacement of PHO ingredients with fat alternatives having increasingly lower or no trans fat content. In the present study, we developed a Fourier-transform infrared (FTIR) spectroscopic procedure in conjunction with multivariate partial least squares regression (PLSR) and found it suitable for the accurate prediction of low (0.5%) total trans fat content, as percentage of total fat, measured as fatty acid methyl esters (FAME), in the lipids extracted from 24 representative fast foods. This multivariate data analysis approach is relevant because the precision of the current univariate FTIR official method (AOCS Cd 14-09) is reportedly poor below 2% of total fat, while PLSR has allowed us to accurately predict the concentration of low trans fat in fast foods. The performance of a portable FTIR device was also evaluated and compared to that of a benchtop FTIR spectrometer. For both infrared data sets, PLSR-predicted concentrations of total trans FAME, ranging from approximately 0.47% to 11.40% of total FAME, were in good agreement with those determined by a primary reference gas chromatography (GC) method (R2>0.99); high prediction accuracy was also evidenced by low root mean square error of cross-validation (RMSECV) values. The lowest RMSECV error of 0.12% was obtained with the portable device. The lowest total trans FAME concentration, determined by GC to be 0.42%, was accurately predicted by the portable FTIR/PLSR procedure as 0.47% of total FAME.
- 著者
- Ali Reza Fardin-Kia Sanjeewa R. Karunathilaka Betsy Jean Yakes Kyungeun Lee Zachary Ellsworth Lea Brückner Magdi M. Mossoba
- 出版者
- Japan Oil Chemists' Society
- 雑誌
- Journal of Oleo Science (ISSN:13458957)
- 巻号頁・発行日
- vol.68, no.11, pp.1105-1112, 2019 (Released:2019-11-07)
- 参考文献数
- 29
- 被引用文献数
- 5
We recently observed that the weak near-infrared (NIR) band near 5260 cm–1 was relatively more intense for extra virgin olive oil (EVOO) than for refined olive oil (ROO). We also observed that its intensity was diminished upon heating and erroneously presumed that it may be attributed to volatile carbonyl components in EVOO. In the present study we demonstrate for the first time that this band is primarily attributed to a water O-H combination band. To accurately determine the intensity of this weak band, observed on a shifted and sloping baseline, we measured the peak-to-peak (p-p) height of its first derivative. An exponential calibration curve for p-p height versus gravimetrically-determined concentration of spiked water was satisfactorily generated. The calibration curve was first evaluated by using independent sets of gravimetrically prepared test samples. Subsequently, it was used to determine the moisture content, a quality parameter, for a limited set of authenticated reference olive oils whose quality and purity were confirmed by official methods. These concentrations, 0.098-0.12% H2O (w/w) for EVOO, 0.022-0.030% H2O (w/w) for ROO, and 0.028-0.054% H2O (w/w) for pomace olive oil (POO), were consistent with those reported in the literature. For 88 commercial products investigated, the moisture levels fell in the range from 0.026% to 0.13% (w/w). The correlation between moisture content and other olive oil quality parameters has been reported in the literature and has yet to be further investigated.