<Emphasis Type="Italic">Trans</Emphasis> FA content in Danish margarines and shortenings

Margarines and shortenings have been major contributors to the intake by humans of the probably atherogenic trans FA (TFA). In 1999, all 73 brands of margarines and shortenings on the Danish market were analyzed by GLC on a 50-m highly polar capillary column, and the results were compared with similar investigations in 1992 and 1995. A gradual decline of TFA in Danish margarines was observed. From 1992 to 1995, a reduction of TFA from 10.4 to 3.6% took place in margarines with 20–40% linoleic acid. In 1999, TFA was practically absent in all the margarines, but it remained unchanged in shortenings, averaging about 6–7%. Long-chain TFA from hydrogenated fish oil, although present in 13 brands in 1995, were not found at all in the 1999 samples. Trans-linoleic acids or CLA were not found. The reduction in TFA content in margarines has not resulted in a systematic change over the years in the content of saturated FA, monounsaturated FA, or PUFA. Calculated from sales figures, the intake of TFA decreased from 2.2 g per capita per year in 1992, to 1.5 g in 1995, and to 0.4 g in 1999.     

<Emphasis Type="Italic">trans</Emphasis> Fatty Acid Content of Canadian Margarines Prior to Mandatory <Emphasis Type="Italic">trans</Emphasis> Fat Labelling

Dietary trans fatty acids (TFA) are of major concern because of their adverse effects on blood lipid levels and coronary heart disease. In Canada, margarines were significant sources of TFA during the 1980s and 1990s. However, this is expected to change with increased public awareness over their adverse health effects and the introduction of new legislature to include TFA content on the Nutritional Facts table of food labels. In this study, the TFA content of the top-selling 29 Canadian margarines, which represented 96.3% of the market share, was determined by capillary gas-liquid chromatography in order to assess the influence of regulatory development during the 3-year transition period between the announcement of new food labelling regulations in Canada that require mandatory declaration of the trans fat content in most pre-packaged foods in January 2003 and its enforcement on 12 December 2005. The 29 margarines included 15 tub margarines made from non-hydrogenated vegetable oils (NHVO-tub margarines), 11 tub margarines made from partially hydrogenated vegetable oils (PHVO-tub margarines) and three print margarines, which were also made from partially hydrogenated vegetable oils (PHVO-print margarines). The 15 NHVO tub-margarines accounted for 71% of the total margarine market share and generally contained less than 2% TFA (mean value 0.9 ± 0.3% of total fatty acids). The mean total TFA contents of PHVO-tub margarines and PHVO-print margarines, were 20.0 ± 4.5% and 39.6 ± 3.5%, and their market shares were 19.3 and 6.0%, respectively. Although during the last 10 years, increasing number of soft tub margarines that contained very little trans fats have been made available in Canada, the PHVO-tub- and -print margarines still contain high levels of trans fats similar to those margarines that were sold in the 1990s. The market share data suggest that the margarines prepared using NHVO and containing almost no TFA were preferred by Canadians over those margarines prepared using PHVO, even before the mandatory declaration of TFA content came into effect on 12 December 2005.     

The Diversity of Health Effects of Individual <Emphasis Type="Italic">trans</Emphasis> Fatty Acid Isomers

There are multiple adverse effects of trans fatty acids (TFA) that are produced by partial hydrogenation (i.e., manufactured TFA), on CVD, blood lipids, inflammation, oxidative stress, endothelial health, body weight, insulin sensitivity, and cancer. It is not yet clear how specific TFA isomers vary in their biological activity and mechanisms of action. There is evidence of health benefits on some of the endpoints that have been studied for some animal TFA isomers, such as conjugated linoleic acid; however, these are not a major TFA source in the diet. Future research will bring clarity to our understanding of the biological effects of the individual TFA isomers. At this point, it is not possible to plan diets that emphasize individual TFA from animal sources at levels that would be expected to have significant health effects. Due to the multiple adverse effects of manufactured TFA, numerous agencies and governing bodies recommend limiting TFA in the diet and reducing TFA in the food supply. These initiatives and regulations, along with potential TFA alternatives, are presented herein.     

Fatty acid (FA) composition and contents of <Emphasis Type="Italic">trans</Emphasis> unsaturated FA in hydrogenated vegetable oils and blended fats from Pakistan

This study presents the FA composition and trans FA (TFA) contents of different hydrogenated vegetable oils and blended fats marketed in Pakistan. Thirty-four vanaspati (vegetable ghee), 11 shortenings, and 11 margarines were analyzed. The contents of saturated FA, cis monounsaturated FA, and cis PUFA were in the following ranges: vanaspati 27.8–49.5, 22.2–27.5, 9.3–13.1%; vegetable shortenings 37.1–55.5, 15.8–36.0, 2.7–7.0%; and margarines 44.2–55.8, 21.7–39.9, 2.9–20.5%, respectively. Results showed significantly higher amounts of TFA in vanaspati samples, from 14.2 to 34.3%. Shortenings contained TFA proportions of 7.3–31.7%. The contents of TFA in hard-type margarines were in the range of 1.6–23.1%, whereas soft margarines contained less than 4.1% TFA.     

Preparation of plastic fats with zero <Emphasis Type="Italic">trans</Emphasis> FA from palm oil

A series of plastic fats containing no trans FA and having varying melting or plastic ranges, suitable for use in bakery, margarines, and for cooking purposes as vanaspati, were prepared from palm oil. The process of fractionating palm oil under different conditions by dry and solvent fractionation processes produced stearins of different yields. Melting characteristics of stearin fractions varied depending on the yield and the process. The lower-yield stearins were harder and had a wider plastic range than those of higher yields. The fractions with yields of about 35% had melting profiles similar to those of commercial vanaspati. The plastic range of palm stearins was further improved by blending them with corresponding oleins and with other vegetable oils. The plasticity or solid fat content varied depending on the proportion of stearin. Blends with higher proportions of stearins were harder than those with lower proportions. the melting profiles of some blends, especially those containing 40–60% stearin of about 25% yield and 40–60% corresponding oleins or mahua or rice bran oils, were similar to those of commercial vanaspati and bakery shortenings. These formulations did not contain any trans FA, unlike those of commercial hydrogenated fats. Thus, by fractionation and blending, plastic fats with no trans acids could be prepared for different purposes to replace hydrogenated fats, and palm oil could be utilized to the maximum extent.     

Formulation of zero-<Emphasis Type="Italic">trans</Emphasis> acid shortenings and margarines and other food fats with products of the oil palm

The fruit of the oil palm yields two types of oil. The flesh yields 20–22% of palm oil (C16∶0 44%, C18∶1 39%, C18∶2 10%). This represents about 90% of the total oil yield. The other 10%, obtained from the kernel, is a lauric acid oil similar to coconut oil. Palm oil is semisolid, and a large part of the annual Malaysian production of about 14 million tonnes is fractionated to give palm olein, which is widely used for industrial frying, and palm stearin, a valuable hard stock. Various grades of the latter are available. Formulae have been developed by straight blending and by interesterification of palm oil and palm kernel oil to produce shortenings and margarines using hydrogenated fats to give the consistency required. Products that include these formulations are cake shortenings, vanaspati (for the Indian subcontinent), soft and brick margarines, pastry margarines, and reduced fat spreads. Other food uses of palm products in vegetable-fat ice cream and cheese, salad oils, as a peanut butter stabilizer, and in confectioners fats are discussed briefly here.     

Separation and identification of phenolic acids and related compounds by gas chromatography and fourier transform infrared spectroscopy

Phenolic acids and related compounds were separated by gas chromatography using three separate columns. One of these columns was coupled to a Fourier transform infrared spectrometer. The trimethylsilyl derivatives could be separated and identified by comparing the relative retention times of the three different columns. However, where there was overlap, the accompanying infrared data clearly distinguished between the questionable derivatives, thus enabling characterization of all derivatives.The use of trade, firm, or corporation names in this article is for the information and convenience of the reader. Such use does not constitute an official endorsement or approval by the U.S. Department of Agriculture or the Forest Service of any product or service to the exclusion of others that may be suitable.     

Preparative Separation of <Emphasis Type="Italic">cis</Emphasis>- and <Emphasis Type="Italic">trans</Emphasis>-Isomers of Unsaturated Fatty Acid Methyl Esters Contained in Edible Oils by Reversed-Phase High-Performance Liquid Chromatography

In order to measure exactly the trans-fatty acids content in food materials, a preparative group separation of cis- and trans-isomers of unsaturated fatty acid methyl esters (FAMEs) was achieved by an isocratic reversed-phase HPLC (RP-HPLC) method. The trans-isomers of 16:1, 18:1, 18:2, 18:3, 20:1 and 22:1 FAMEs were readily separated from the corresponding cis-isomers by a COSMOSIL Cholester C18 column (4.6 mm I.D. × 250 mm, Nacalai Tesque) or a TSKgel ODS-100Z column (4.6 mm I.D. × 250 mm, TOSOH), using acetonitrile as the mobile phase. This method was applied for determining the trans-18:1 fatty acid content in partially hydrogenated rapeseed oil. The methyl esters of cis- and trans-18:1 isomers of the oil were collected as two separate fractions by the developed RP-HPLC method. Each fraction was analyzed by gas chromatography (GC) for both qualitative and quantitative information on its positional isomers. By a combination of RP-HPLC and GC methods, a nearly complete separation of cis- and trans-18:1 positional isomers was achieved and the trans-18:1 fatty acid content was able to be evaluated more precisely than is possible by the direct GC method. The reproducibility of cis- and trans-18:1 isomers fractionated by the RP-HPLC method was better than 98%. These results suggested that the preparative RP-HPLC method developed in this study could be a powerful tool for trans-fatty acid analysis in edible oils and food products as an alternative to silver-ion chromatography.     

Monitoring of Fat Content,Free Fatty Acid and Fatty Acid Profile Including <Emphasis Type="Italic">trans</Emphasis> Fat in Pakistani Biscuits

The fat contents of 12 brands of biscuits were extracted and evaluated for free fatty acids (FFA) and their fatty acid composition (FAC). The oil content and FFA varied from 13.7 to 27.6% and 0.2 to 1.0%, respectively. The FAC was analyzed by gas chromatography–mass spectroscopy with particular emphasis on trans fatty acids (TFA). Total saturated, unsaturated, cis-monounsaturated and polyunsaturated fatty acids were determined in the range of 37.9–46.9, 53.0–62.0, 12.3–43.7 and 0.1–9.2%, respectively. The high amount of TFA was observed in all biscuit samples and varied from 9.3 to 34.9%. The quantity and quality of the lipid fraction of the biscuits indicated that the all analyzed biscuits are a rich source of fat, saturated fatty acids and trans fatty acids, consequently not suitable for the health of consumers. The high content of trans fatty acids and palmitic acid also indicated that blends of RBD palm oil and partially hydrogenated oil had been used in the biscuit manufacturing.     

Zero-<Emphasis Type="Italic">trans</Emphasis> shortening using palm stearin and rice bran oil

Several pilot-scale trials reported in this paper, using palm stearin-rice bran oil (PS-RBO) blends, obviously did not contain trans FA (TFA), whereas the commercial products were found to contain 18–27% TFA. The effects of processing conditions such as rate of agitation, crystallization temperature, and composition of the blends on the crystal structure of shortenings were studied. The products were evaluated for their physicochemical characteristics using DSC, X-ray diffraction (XRD), HPLC, and FTIR techniques. The formulation containing 50% PS and 50% RBO showed melting and cooling characteristics similar to those of hydrogenated commercial “vanaspati” samples. Analysis of the FA composition revealed that the formulated shortenings contained 15–19% C_18∶2 PUFA. Tocopherol and tocotrienol contents of the experimental shortenings were in the range of 850–1000 ppm with oryzanol content up to 0.6%. XRD studies demonstrated that the crystal form in the shortenings was predominantly the most stable β′ form, and there was less of the undesirable β form.     

Influence of triacylglycerol characterics on the determination of free fatty acids in vegetable oils by fourier transform infrared spectroscopy

A rapid and direct Fourier transform infrared (FTIR) spectroscopic method using a 25-μm NaCl transmission cell was developed for the determination of free fatty acids (FFA) in six important vegetable oils (corn, soybean, sunflower, palm, palm kernel, and coconut oils) that differ in fatty acid profile. The calibrations were established by adding either standard FFA (oleic, lauric acids) or a representative mixture of FFA obtained after saponification of the refined oils. For all oils, up to a FFA level of 6.5% for coconut oil, the best correlation coefficient was obtained by linear regression of the free carboxyl absorption at 1711 cm⁻¹. All correlation coefficients were greater than 0.993, and no significant difference between the calibration methods could be detected. Upon validation of the calibration, no significant difference (α=0.05) between the “actual” and the “FTIR predicted” FFA values could be observed. The calibration models developed for the six oils differed significantly and indicate the need to develop a calibration that is specific for each oil. In terms of repeatability and accuracy, the FTIR method developed was excellent. Because of its simplicity, quick analysis time of less than 2 min, and minimal use of solvents and labor, the introduction of FTIR spectroscopy into laboratory routine for FFA determination should be considered.     

Rapid quantitative determination of free fatty acids in fats and oils by fourier transform infrared spectroscopy

Rapid direct and indirect Fourier transform infrared (FTIR) spectroscopic methods were developed for the determination of free fatty acids (FFA) in fats and oils based on both transmission and attenuated total reflectance approaches, covering an analytical range of 0.2–8% FFA. Calibration curves were prepared by adding oleic acid to the oil chosen for analysis and measuring the C=O band @ 1711 cm^–1 after ratioing the sample spectrum against that of the same oil free of fatty acids. For fats and oils that may have undergone significant thermal stress or extensive oxidation, an indirect method was developed in which 1% KOH/methanol is used to extract the FFAs and convert them to their potassium salts. The carboxylate anion absorbs @ 1570 cm^–1, well away from interfering absorptions of carbonyl-containing oxidation end products that are commonly present in oxidized oils. Both approaches gave results comparable in precision and accuracy to that of the American Oil Chemists’ Society reference titration method. Through macroprogramming, the FFA analysis procedure was completely automated, making it suitable for routine quality control applications. As such, the method requires no knowledge of FTIR spectroscopy on the part of the operator, and an analysis takes less than 2 min.     

Upgrading the AOCS infrared trans method for analysis of neat fats and oils by fourier transform infrared spectroscopy

An automated protocol for the direct, rapid determination of isolated trans content of neat fats and oils by Fourier transform infrared (FTIR) spectroscopy was devised, based on a simple modification of the standard AOCS trans method, eliminating the use of CS₂ and methylation of low trans samples. Through the use of a commercially available, heated transmission flow cell, designed specifically for the analysis of neat fats and oils, a calibration (0–50%) was devised with trielaidin spiked into a certified, trans-free soybean oil. The single-beam spectra of the calibration standards were ratioed against the single-beam spectrum of the base oil, eliminating the spectral interference caused by underlying triglyceride absorptions, facilitating direct peak height measurements as per the AOCS IR trans method. The spectrometer was preprogrammed in Visual Basic to carry out all spectral manipulations, measurements, and calculations to produce trans results directly as well as to provide the operator with a simple interface to work from. The derived calibration was incorporated into the software package, obviating the need for further calibration because the program includes an automatic recalibration/standardization routine that automatically compensates for differences in optical characteristics between instruments, instrument drift over time, and cell wear. The modified AOCS FTIR analytical package was evaluated with Smalley check samples for repeatability, reproducibility, and accuracy, producing SD of ± 0.07, 0.13, and 0.70 trans, respectively, the FTIR predictions being linearly related to the Smalley means (r=0.999; SD=± 0.46), and well within one SD of the Smalley sample means. Calibration transfer was assessed by implementing the calibration on a second instrument and reanalyzing the Smalley check samples in cells of two different pathlengths (25- and 50-μm). There were no statistically significant differences between the FTIR trans predictions obtained for the Smalley samples from the two instruments and two cells, indicating that the software was able to adjust the calibrations to compensate for differences in instrument response and cell pathlength. The FTIR isolated trans analysis protocol developed by the McGill IR Group has the benefit of being based on the principles of an AOCS-approved method, matches its accuracy, and allows the analysis to be performed on both neat fats and oils, producing trans predictions in less than 2 min per sample. It is suggested that this integrated approach to trans analysis, which requires a minimum level of sample manipulation and operator skill, be considered as a modification of the proposed Recommended Practice CD14b-95.     

Monitoring the oxidation of edible oils by Fourier transform infrared spectroscopy

Edible fats and oils in their neat form are ideal candidates for Fourier transform infrared (FTIR) analysis, in either the attenuated total reflectance or the transmission mode. FTIR spectroscopy provides a simple and rapid means of following complex changes that take place as lipids oxidize. Safflower and cottonseed oils were oxidized under various conditions, and their spectral changes were recorded and interpreted. The critical absorption bands associated with common oxidation end products were identified by relating them to those of spectroscopically representative reference compounds. The power and utilty of FTIR spectroscopy to follow oxidative changes was demonstrated through the use of “real-time oxidation plots.” A quantitative approach is proposed in which standards are used that are spectroscopically representative of oxidative end products and by which the oxidative state of an oil can be defined in terms of percent hydroperoxides, percent alcohols and total carbonyl content. By using either relative absorption as a basis or calibrating on representative standards, FTIR analysis provides a rapid means of evaluating the oxidative state of an oil or of monitoring changes in oils undergoing thermal stress.     

Lipid Classes and Fatty Acid Composition of the Tropical Nudibranch Mollusks <Emphasis Type="Italic">Chromodoris</Emphasis> sp. and <Emphasis Type="Italic">Phyllidia coelestis</Emphasis>

Two nudibranch mollusks, Chromodoris sp. and Phyllidia coelestis, collected from tropical waters of the Northwestern Pacific, were analyzed for lipids. The aim of this study was to fill the gap in knowledge of lipid biochemistry of mollusks. Phospholipids (PL) were the dominating lipid class followed by sterols (13%). Neutral lipids were not detected in Chromodoris sp. By contrast, P. coelestis contained TAG, diacylglyceryl ether, long chain alcohol and esters of sterols. Among PL, PC was predominant (about 50%); PE, PS and CAEP were almost in equal proportions. Sixty five FA were identified as methyl esters and N-acyl pyrrolidides by GC-MS. The sea slugs exhibited a wide diversity of FA. The common marine n-3 PUFA, 20:5n-6 and 22:6n-3, constituted 0.6-1.3% of the total FA, whereas n-6 PUFA, 22:4n-6, 20:4n-6, and 18:2n-6, were the main (25%). Among monounsaturated FA, 7-21:1 was the main (up to 6.2%). The non-methylene-interrupted (NMI) FA were found (9.4 and 12.4%), including the known 5,11-20:2, 5,13-20:2, 7,13-22:2, 7,15-22:2 and a novel isomer 7,13-21:2 (up to 3.9%). The pathway of its biosynthesis was suggested. A series of very long chain FA (VLC FA), with the main 5,9-25:2 and 5,9-26:2, were identified. High level of VLC FA (8.7 and 11.7%) in sea slugs is apparently the result of predation on sponges. Another unique feature concerned a high abundance of various odd and branched FA (16.7 and 34%), which could have originated from the dietary origin or symbiotic bacteria. This is the first report on lipid and FA composition of nudibranchs.     

<Emphasis Type="Italic">Trans</Emphasis> FA in sunflower oil at different steps of refining

The contents of total trans FA of sunflower oils at different stages of refining processes were determined by capillary GLC. The contents of 18∶1, 18∶2, and 18∶3 trans acids were 0.22±0.03, 2.31±0.23, and 0.03±0.01%, respectively, in physically refined sunflower oils, and 0.05±0.01, 0.69±0.26, and 0.02±0.01%, respectively, in chemically refined sunflower oils. The total trans FA contents drastically increased at the end of the physical refining process. The total trans FA contents of chemically refined sunflower oils were <1%. Because of the high temperature applied in the last stage of physical refining, the content of total trans FA was higher than in chemically refined sunflower oils. The last-stage conditions should be carefully evaluated to reduce the formation of trans FA during physical refining.     

<Emphasis Type="Italic">Santalum </Emphasis><Emphasis Type="Italic">insulare</Emphasis> Acetylenic Fatty Acid Seed Oils: Comparison within the <Emphasis Type="Italic">Santalum</Emphasis> Genus

The sandalwood kernels of Santalum insulare (Santalaceae) collected in French Polynesia give seed oils containing significant amounts of ximenynic acid, E-11-octadecen-9-oic acid (64–86%). Fatty acid (FA) identifications were performed by gas chromatography/mass spectrometry (GC/MS) of FA methyl esters. Among the other main eight identified fatty acids, oleic acid was found at a 7–28% level. The content in stearolic acid, octadec-9-ynoic acid, was low (0.7–3.0%). An inverse relationship was demonstrated between ximenynic acid and oleic acid using 20 seed oils. Results obtained have been compared to other previously published data on species belonging to the Santalum genus, using multivariate statistical analysis. The relative FA S. insulare composition, rich in ximenynic acid is in the same order of those given for S. album or S. obtusifolium. The other compared species (S. acuminatum, S. lanceolatum, S. spicatum and S. murrayanum) are richer in oleic acid (40–59%) with some little differences in linolenic content.     

Industrially Produced <Emphasis Type="Italic">trans</Emphasis> Fat in Foods in Australia

Selected foods sampled from Australian supermarkets and fast food outlets were analyzed for trans fat (TF) content. The product with the highest amount of TF (6.3 g/100 g product) was a household shortening. The TF contents in spreads were remarkably low (average 0.5, range 0.2–1.3 g/100 g product) with only 3 out of 15 exceeding the maximum level (2.0 g/100 g fat) permitted in Denmark. Ready-to-eat French fries purchased from all but one (1.5 g/100 g product) fast food outlet contained generally low levels of TF (average 0.4, range 0.3–0.7 g/100 g product), and the majority of the outlets appeared to have used non-hydrogenated vegetable oils for frying. Frozen French fries and ready-to-eat potato chips purchased from supermarkets were also low in TF (average 0.1 and 0.2 g/100 g product, respectively). So were the bakery products (biscuits, cakes, bread, cake and muffin mixes) except for croissants. However, 9 out of the 103 products tested would have been prohibited from sale in Denmark, while 25 and 12 products would have failed to qualify for ‘trans fat-free’ claims according to the mandatory labeling regulations currently in force in Canada the USA, respectively.     

Butters Varying in <Emphasis Type="Italic">trans</Emphasis> 18:1 and <Emphasis Type="Italic">cis</Emphasis>-9,<Emphasis Type="Italic">trans-</Emphasis>11 Conjugated Linoleic Acid Modify Plasma Lipoproteins in the Hypercholesterolemic Rabbit

The experiment was designed to study the effects of butters differing in conjugated linoleic acid (CLA) and trans 18:1 contents on lipoproteins associated with the risk of atherogenesis. New Zealand White male rabbits (9.6 weeks; 2.1 kg) were assigned for 6 or 12 weeks to three diets (n = 6 per diet) made of conventional pellets with 0.2% cholesterol and with 12% fat provided from a butter poor in trans-10 and trans-11 18:1 and in CLA (standard group), or rich in trans-10 18:1 (trans-10 18:1 group) or rich in trans-11 18:1 and in cis-9,trans-11 CLA (trans-11 18:1/CLA group). Blood samples were collected at the end of dietary treatments. Lipoproteins were separated by gradient-density ultracentrifugation. Lipid classes were determined enzymatically and apolipoproteins A-I and B by radial immunodiffusion. Mainly in the 12-week rabbits, higher plasma triglycerides and apolipoprotein B levels shown in the standard and trans-10 18:1 groups compared with those in the trans-11 18:1/CLA group are associated with higher plasma levels of very low density lipoproteins (VLDL) and low density lipoproteins (LDL) also shown in these two groups. In the 12-week rabbits, a shift towards denser LDL, considered as more atherogenic, was shown only in the trans-10 18:1 group. In these animals, the VLDL + LDL to HDL ratio was 1.7-2.3 times higher in the trans-10 18:1 group than in the other groups (P = 0.076). These results suggest a rather neutral effect of trans-11 18:1/CLA butter towards the risk of atherogenesis, whereas trans-10 18:1 butter would tend to be detrimental.     

Determination of totaltrans fatty acids in foods: Comparison of capillary-column gas chromatography and single-bounce horizontal attenuated total reflection infrared spectroscopy

The totaltrans fatty acid content of 18 food products was determined, after acid hydrolysis, extraction and methylation of fatty acids, by gas chromatography with a polar 100% cyanopropylsiloxane capillary column and by single-bounce horizontal attenuated total reflection spectroscopy (SB-HATR). Thetrans fatty acid methyl esters (FAME) of 9-hexadecenoate (9t-16:1), 9-octadecenoate (9t-18:1), and 9,12-octadecadienoate (9t,12t-18:2) were identified by comparison of their retention times with those of known standards and quantitated. The isomersc,t- andt,c-18:2 were identified from their published retention times and included in the quantitation oftrans FAME. Neat 50-μL portions of the FAME that were used for gas-chromatographic analysis also were analyzed by SB-HATR. This technique requires neither weighing nor quantitative dilution of test portions prior to spectroscopic quantitation of isolated double bonds oftrans configuration. A symmetric 966-cm⁻¹ absorption band on a horizontal background was obtained from unhydrogenated soybean oil FAME as the reference material. For 9 of 11 products withtrans fat content>5% of total fat, results obtained by SB-HATR were higher than those obtained by gas chromatography. Results obtained by the gaschromatographic procedure were slightly to significantly higher than those obtained by SB-HATR for the six foods in whichtrans fat content was <5% of total fat.