Two functional food oils, namely extra virgin olive oil (EVOO) and virgin coconut oil (VCO) have been analyzed simultaneously using Fourier transform infrared (FTIR) spectroscopy. The performance of multivariate calibration of principle component regression (PCR) and partial least square regression (PLSR) was evaluated in order to give the best prediction model for such determination. FTIR spectra were treated with several treatments including mean centering (MC), derivatization, and standard normal variate (SNV) at the combined frequency regions of 3050 – 3000, 1660 – 1650, and 1200 – 900 cm-1. Based on its capability to give the highest values of coefficient of correlation (R) for the relationship between actual value of EVOO/VCO and FTIR predicted value together with the lowest values of root mean square error of calibration (RMSEC), PLSR with mean centered-first derivative spectra was chosen for simultaneous determination of EVOO and VCO. It can be concluded that FTIR spectroscopy combined with multivariate calibration of PLSR was successfully applied to simultaneously quantify EVOO and VCO with acceptable parameters.
The present study was carried out to characterize red fruit (Pandanus conoideus Lam) oil (RFO) in term of FTIR spectra, fatty acid composition, and volatile compounds. FTIR spectrum of RFO was slightly
different from other common vegetable oils and animal fats, in which in the frequency range of 1750 – 1700 cm-1, RFO appear two bands. The main fatty acid composition of RFO is oleic acid accounting for 68.80% followed by linoleic acid with the concentration of 8.49%. The main volatile compounds of RFO as determined using gas chromatography coupled with mass spectrometry (GC-MS) and headspace analyser are 1,3-dimethylbenzene (27.46%), N-glycyl- L-alanine (17.36%), trichloromethane (15.22%), and ethane (11.43%).
FTIR spectroscopy in combination with multivariate calibrations, i.e. partial least square (PLS) and principle component regression (PCR) was developed for quantitative analysis of cod liver oil (CLO) in binary mixture with corn oil (CO). The spectra of CLO, CO and their blends with certain concentrations were scanned using horizontal attenuated total reflectance (HATR) accessory at mid infrared (MIR) region of 4,000 – 650 cm-1. The optimal spectral treatments selected for calibration models were based on its ability to provide the highest values of coefficient of determination (R2) and the lowest values of root mean error of calibration (RMSEC). PLS was slightly well suited for quantitative analysis of CLO compared to PCR. FTIR spectroscopy in combination with multivariate calibration offers rapid, no excessive chemical reagent, and easy in operational to be applied for determination of CLO in binary mixture with other oils.
The main objective of the present study was to investigate the effects of the frying media and storage time on the fatty acid composition (FAC) and iodine value (IV) of deep-fat fried potato chips. The frying experiment was conducted at 180ºC for five consecutive days. Six frying media were considered as the main treatments: refined, bleached, deodorized (RBD) palm olein (A), canola oil (C), RBD palm olein/sesame oil (AB, 1:1 w/w), RBD palm olein/canola oil (AC, 1:1, w/w), sesame oil/canola oil (BC, 1:1, w/w), and RBD palm olein/sesame oil/canola oil (ABC, 1:1:1, w/w/w). The initial degrees of unsaturation of the consumed oils, A, C, AB, AC, BC, and ABC, were 58.6, 94.0, 68.0, 72.2, 87.7, and 75.8 (g/100 g), respectively. The fatty acid analysis showed that there was a decrease in both the linolenic acid (C18:3) and linoleic acid (C18:2) contents, whereas the palmitic acid (C16:0) increased with a prolonged frying time. The chemical analysis showed that there was a significant (p < 0.05) difference in terms of the IV for each frying oil during the five consecutive days of frying (day 0 to 5). Oil C had the least stability in terms of deep-fat frying due to a high level of unsaturated fatty acids. Conversely, oil AC had the best stability due to the smallest reduction of the C18:2/C16:0 ratio and the IV.
Gelatins from the skin of four local marine fish, namely “kerapu” (Epinephelus sexfasciatus), “jenahak” (Lutjianus argentimaculatus), “kembung” (Rastrelliger kanagurta), and “kerisi” (Pristipomodes typus) have been successfully extracted by acid extraction. Results characterization showed that the fish gelatins were comparable to the fish gelatins from other fish species previously reported. They appeared snowy white in color with crystal-like and light texture. The gelatine extracted from “kerapu” had the strongest fishy odor, followed by the gelatines derived from “jenahak”, “kembung” and “kerisi”. In terms of bloom strength, the gelatin extracted from “kerapu” was found to be the strongest one compared to others, with the bloom value of more than 2000 g. The gelatins developed in this study contained almost all essential amino acids, with glycine being the most predominant one.
The use of Fourier transform infrared (FTIR) spectroscopy coupled with chemometric techniques to differentiate butter from beef fat (BF) was investigated. The spectral bands associated with butter, BF, and their mixtures were scanned, interpreted, and identified by relating them to those spectroscopically representative to pure butter and BF. For quantitative analysis, partial least square (PLS) regression was used to develop a calibration model at the selected fingerprint regions of 1500-1000 cm-1, with the values of coefficient of determination (R2) and root mean square error of calibration (RMSEC) are 0.999 and 0.89% (v/v), respectively. The PLS calibration model was subsequently used for the prediction of independent samples containing butter in the binary mixtures with BF. Using 6 principal components, root mean square error of prediction (RMSEP) is 2.42% (v/v). These results proved that FTIR spectroscopy in combination with multivariate calibration can be used for the detection and quantification of BF in butter formulation for authentication use.
Date palm is an important plant in arid regions with more than 20 varieties reported all over the world. Date seed is a byproduct of date fruit industry which is normally being discarded, used as animal feed ingredient or turned into non-caffeinated coffee by the Arabs. About 11-18% of date fruit weight is the seed which is composed of carbohydrates, dietary fiber, fat, ash and protein. In addition, the antioxidant content in date seed oil (DSO) was found to be comparable with olive oil, which can be as a good source of antioxidant in order to fulfill the consumers demand. Oleic acid is the major fatty acid found in DSO, followed by lauric, linoleic, palmitic and myristic acid. However, different varieties of date fruits have different fatty acid compositions. This paper reviewed the potential use of date seed and date seed oil in order to discover and develop its usage and find out the suitable application of these seed and oil.