Effects of fresh and used hydrogenated soybean oil on reproduction and teratology in rats

Groups of 25 pairs of two generations of male and female rats were fed diets containing 15% of either fresh hydrogenated soybean oil (iodine value, 107), a similar fat used 56 hr for deep frying or an unhydrogenated mixture of fats and oils with a fatty acid composition similar to the hydrogenated soybean oil. The first two litters of each generation were permitted to be born naturally. During the third pregnancy of each generation, one-half of the females were sacrificed on day 13 of gestation and inspected for early embryonic death. The remaining females were sacrificed on day 21 of gestation, and the fetuses were examined for either skeletal or softtissue abnormalities. There was no evidence of any deleterious effects on the reproductive parameters nor any teratogenic effects due to either hydrogenated soybean oil, a similar oil used for frying foods for 56 hr or an unhydrogenated mixture of fats and oils.     

Biliary and fecal steroid excretion in rats fed partially hydrogenated soybean oil

Male Wistar rats were fed cholesterol-free or cholesterol-enriched diets containing partially hydrogenated soybean oil with different levels of trans-fatty acids or unhydrogenated soybean oil at the 10% level. The linoleic acid content of hydrogenated fat diets was adjusted to 3.6% of the total energy. Hydrogenated fat diets contained 29% and 41% trans-acids, mainly as t-18:1. Trans-fats exerted no untoward effects on growth parameters, but increased liver weight. Dietary hydrogenated fats influenced neither the concentration nor composition of biliary steroids, irrespective of the presence or absence of cholesterol in the diet. In rats fed a cholesterol-free diet, daily fecal output of neutral and acidic steroids was enhanced by hydrogenated fats and the magnitude of augmentation was proportional to the dietary level of trans-fatty acids. The increased fecal steroid excretion corresponded to an increase in total excreta. Hydrogenated fats also tended to enhance bile acid excretion when feeding a cholesterol-enriched diet. The results suggest that dietary trans-fatty acids, in relation to cis-polyunsaturated fatty acids, provoke demonstrable change in steroid homeodynamics.     

Effects of highly hydrogenated soybean oil and cholesterol on plasma,liver cholesterol,and fecal steroids in rats

We investigated the relationship between dietary highly hydrogenated soybean oil (HSO) and cholesterol transport in rats. In the first study, to examine the effects of cholesterol transport of different concentrations of HSO in dietary oil, rats were given one of the three diets containing 0, 25, or 50% HSO in dietary oil with cholesterol (5 g/kg diet) or a diet without HSO and cholesterol for 22 d. Feeding the high concentration of HSO prevented the increase in plasma total cholesterol, hepatic total lipids, and cholesterol and the decrease in high-density lipoprotein-cholesterol, which were caused by dietary cholesterol. Moreover, HSO increased the fecal excretion, fecal lipids, and steroids in a dose-dependent manner. In the second study, to examine the effects on cholesterol transport of redistribution of stearic acid in the triacylglycerol species contained in HSO, rats were given one of the six diets containing HSO (distearoylmonoacylglycerol and tristearoylglycerol)-rich, monostearoylglycerol-rich, or palmitic acid-rich oil with/without cholesterol (5 g/kg diet), for 30 d. Whereas the accumulation of cholesterol in the body was reduced, cholesterol excretion was enhanced effectively in rats given the HSO-rich diet compared with rats given the monostearoylglycerol-rich diet. These results suggested that not only the high concentration of stearic acid but also its uneven distribution in HSO-triacylglycerol contributed to the reduction in intestinal cholesterol absorption in rats.     

Removal of copper from hydrogenated soybean oil

Hydrogenation with a copper-chromite catalyst at 170 C, 30 psi, increased the copper content of a refined, bleached soybean oil from 0.02 to as much as 3.8 ppm. Removing residual copper from soybean oil is essential to the successful use of copper catalysts for selective hydrogenation. Various methods were examined to remove this copper, including alkali refining, bleaching, acid washing, citric acid treatment and cation-exchange resin treatment. Properly conducted, each of the methods except alkali refining gives 95% or higher removal of copper introduced during hydrogenation. Ion exchange appears to be the most economical, but addition of about 0.01% citric acid during deodorization may be needed to inactivate traces of unremoved copper. Soybean oil hydrogenated with a copper-chromite catalyst, bleached or treated with an ion-exchange resin and deodorized with 0.01% citric acid added had low AOM peroxide values and acceptable flavor scores after eight days at 60 C which indicate that removal of residual copper from the oil should be adequate for the production of stable oils low in linolenic acid content. Presented at AOCS Meeting, Chicago, October 1967.     

Highly hydrogenated dietary soybean oil modifies the responses to polychlorinated biphenyls in rats

The effects of dietary highly hydrogenated soybean oil (HSO) upon the changes caused by dietary polychlorinated biphenyls (PCBs) were examined in rats. Six groups of rats were fed the following diets for 30 d: a 20% soybean oil-containing diet (control diet), a diet in which a half of soybean oil was substituted with HSO (HSO-A diet), a diet in which cellulose powder was replaced with HSO (HSO-B diet) and these diets supplemented with 100 ppm PCBs (control+PCBs, HSO-A+PCBs and HSO-B+PCBs diets). Hepatic concentration of PCBs and relative liver weight were markedly decreased in rats fed with the HSO-A+PCBs diet compared with those fed with the other diets containing PCBs. Liver lipids and liver cholesterol were considerably decreased with a reciprocal increase in fecal sterol excretion by rats fed the HSO-A+PCBs and the HSO-B+PCBs diets compared with those fed with the control+PCBs diet. The fatty acid composition in hepatic phospholipids showed an independent increase of the saturated fatty acid content induced by dietary HSO and PCBs. Dietary PCBs also caused decreases in the amounts of monounsaturated and n-3 polyunsaturated fatty acids. These results suggest that dietary HSO prevents accumulation of PCBs in the liver and promotes the excretion of lipids stimulated by PCBs, accompanied by a change in fatty acid metabolism.     

Effect of substitution of low linolenic acid soybean oil for hydrogenated soybean oil on fatty acid intake

Low linolenic acid soybean oil (LLSO) has been developed as a substitute for hydrogenated soybean oil to reduce intake of trans FA while improving stability and functionality in processed foods. We assessed the dietary impact of substitution of LLSO for hydrogenated soybean oil (HSBO) used in several food categories. All substitutions were done using an assumption of 100% market penetration. The impact of this substitution on the intake of five FA and trans FA was assessed. Substitution of LLSO for current versions of HSBO resulted in a 45% decrease in intake of trans FA. Impacts on other FA intakes were within the realm of typical dietary intakes. No decrease in intake of α-linolenic acid was associated with the use of LLSO in place of HSBO because LLSO substitutes for HSBO that are already low in α-linolenic acid.     

Flavor evaluation of copper-nickel hydrogenated soybean oil and blends with unhydrogenated oil

Journal of the American Oil Chemists' Society - Soybean oils hydrogenated to zero linolenate in the pilot plant with a mixed copper-nickel catalyst and a straight copper chromite catalyst were...     

Combustion characteristics of candles made from hydrogenated soybean oil

Hydrogenated soybean oil, referred to as soywax by candle makers, is a renewable and biodegradable alternative to paraffin wax in candle manufacturing. Soywax was investigated for its tendency to produce soot as well as potentially harmful organic volatiles (acrolein, formaldehyde, and acetaldehyde) during combustion. Beeswax and paraffin candles were used as references. A considerable amount of soot was produced from the combustion of paraffin candles, but little or none was observed from soywax candles. Compared to paraffin candles, soywax candles burned at a significantly slower rate and required less air. Small amounts of formaldehyde were detected and quantified in the fumes of burning paraffin candles. However, formaldehyde, peaks found in the chromatograms of soy- and beeswax candles were similar to or slightly higher than that of the blank. Since soywax candles exhibited burning properties similar to those of beeswax candles, soywax shows promise in candle applications.     

Octadecatrienoic fatty acid isomers of partially hydrogenated soybean oil

The octadecatrienoic fatty acids of partially hydrogenated soybean oil (PHSBO) were concentrated, isolated and analyzed. The results indicated that the 18:3 acids present in PHSBO are composed of four isomers. The isomer present in the largest amount (2.7%) is the allcis isomer, c9,c12,c15-18:3 linolenic acid, and comprises 68.60% of all the isomeric 18:3 acids of PHSBO. The remaining three 18:3 isomers found were t9,t12,c15-,t9,c12,c15-and c9,c12,t15-18:3, which in total accounted for 1.2% of the total fatty acids of PHSBO.     

Replacement of partially hydrogenated soybean oil by palm oil in margarine without unfavorable effects on serum lipoproteins

We have compared the effects of three different margarines, one based on palm oil (PALM-margarine), one based on partially hydrogenated soybean oil (TRANS-margarine) and one with a high content of polyunsaturated fatty acids (PUFA-margarine), on serum lipids in 27 young women. The main purpose of the study was to test if replacement of trans fatty acids in margarine by palmitic acid results in unfavorable effects on serum lipids. The sum of saturated fatty acids (12∶0, 14∶0, 16∶0) was 36.3% of total fatty acids in the PALM-diet, the same as the sum of saturated (12∶0, 14∶0, 16∶0) (12.5%) and trans (23.1%) fatty acids in the TRANS-diet. This sum was 20.7% in the PUFA-diet. The content of oleic acid was 37.9, 35.2, and 38.6%, respectively, in the three diets, whereas linoleic acid amounted to 16, 13.5, and 27.3%, respectively. Total fat provided 30–31% and the test margarines 26% of total energy in all three diets. The subjects consumed each of the diets for 17 d in a Latin-square crossover design. There were no significant differences in total cholesterol, low density lipoprotein (LDL)-cholesterol and apolipoprotein B (apoB) between the TRANS-and the PALM-diets. High density lipoprotein (HDL)-cholesterol and apoA-I were significantly higher on the PALM-diet compared to the TRANS-diet whereas the ratio of LDL-cholesterol to HDL-cholesterol was lower, although not significantly (P=0.077) on the PALM-diet. Total cholesterol, LDL-cholesterol, and apoB were significantly lower on the PUFA-diet compared to the two other diets. HDL-cholesterol was not different on the PALM-and the PUFA-diets but it was significantly lower on the TRANS-diet compared to the PUFA diet. Compared to the PUFA-diet the ratio of LDL-to HDL-cholesterol was higher on both the PALM- and the TRANS-diets whereas apoA-I was not different. Triglycerides and lipoprotein (a) were not significantly different among the three diets. We concluded that nutritionally, palmitic acid from palm oil may be a reasonable alternative to trans fatty acids from partially hydrogenated soybean oil in margarine if the aim is to avoid trans fatty acids. A palm oil-based margarine is, however, less favorable than one based on a more polyunsaturated vegetable oil.     

Evaluation of partially hydrogenated methyl esters of soybean oil as biodiesel

Biodiesel, an alternative fuel derived from vegetable oils or animal fats, continues to undergo rapid worldwide growth. Specifications mandating biodiesel quality, most notably in Europe (EN 14214) and the USA (ASTM D6751), have emerged that limit feedstock choice in the production of biodiesel fuel. For instance, EN 14214 contains a specification for iodine value (IV; 120 g I₂/100 g maximum) that eliminates soybean oil as a potential feedstock, as it generally has an IV >120. Therefore, partially hydrogenated soybean oil methyl esters (PHSME; IV = 116) were evaluated as biodiesel by measuring a number of fuel properties, such as oxidative stability, low‐temperature performance, lubricity, kinematic viscosity, and specific gravity. Compared to soybean oil methyl esters (SME), PHSME were found to have superior oxidative stability, similar specific gravity, but inferior low‐temperature performance, kinematic viscosity, and lubricity. The kinematic viscosity and lubricity of PHSME, however, were within the prescribed US and European limits. There is no universal value for low‐temperature performance in biodiesel specifications, but PHSME have superior cold flow behavior when compared to other alternative feedstock fuels, such as palm oil, tallow and grease methyl esters. The production of PHSME from refined soybean oil would increase biodiesel production costs by US$ 0.04/L (US$ 0.15/gal) in comparison to SME. In summary, PHSME are within both the European and American standards for all properties measured in this study and deserve consideration as a potential biodiesel fuel.     

Plasticization effect of hydrogenated transgenic soybean oil on nitrile‐butadiene rubber

Nitrile‐butadiene rubber (NBR) compounds were prepared with different amounts of hydrogenated transgenic soybean oil (HTSO) as renewable plasticizers. For comparison, similar compounds were prepared with petroleum‐based dioctyl‐phthalate (DOP), one of the most common plasticizers for NBR. Four HTSOs with different degree of hydrogenation were used, of which three HTSOs are prepared by hydrogenation reaction at different reaction conditions and one is commercial available. The plasticization effects of HTSO and of DOP were studied by Mooney viscometry, capillary rheometry, differential scanning calorimetry (DSC), and rubber processing analysis (RPA). The results showed that all the HTSOs had better plasticization effect than DOP on NBR. The swelling index result showed that the highly‐hydrogenated‐HTSO plasticized NBR vulcanizate have higher crosslinking density than the low‐hydrogenated ones. It is worthy to mention that, the introduction of high‐hydrogenated‐HTSO greatly improved both the processability of the NBR compounds and the mechanical performance of the final products, which is hard to achieve for most of the plasticizers. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40643.     

Production of cocoa butter-like fats by the lipase-catalyzed interesterification of palm oil and hydrogenated soybean oil

Cocoa butter-like fats were prepared from refined, bleached, and deodorized palm oil (RBD-PO) and fully hydrogenated soybean oil (HSO) by enzymatic interesterification at various weight ratios of substrates. The cocoa butter-like fats were isolated from the crude interesterification mixture by fractional crystallization from acetone. Analysis of these fat products by RP-HPLC in combination with ELSD or MS detection showed that their TAG distributions were similar to that of cocoa butter but that they also contained MAG and DAG, which were removed by silica chromatography. The optimal weight ratio of RBD-PO to HSO found to produce a fat product containing the major TAG component of cocoa butter, namely, 1(3)-palmitoyl-3(1)-stearoyl-2-monoolein (POS), was 1.6∶1. The m.p. of this purified product as determined by DSC was comparable to the m.p. of cocoa butter, and its yield was 45% based on the weight of the original substrates.     

Sensory and chemical stability of tortilla chips fried in canola oil,corn oil,and partially hydrogenated soybean oil

The effects of canola, corn, partially hydrogenated soy (PHS), partially hydrogenated canola (PHC), and low-linolenate canola (LLC) oils on sensory and chemical attributes of tortilla chips were determined initially, after Schaal storage for 8 and 16 d (S8 and S16), and after practical storage for 16 and 24 wk (P16 and P24). Fresh chips were similar to each other in characteristic and off-odors/flavors, except that PHC chips had the lowest characteristic and highest off-odor/flavor. All S8 chips had similar lower (P<0.001) characteristic and greater off-odor/flavor scores than hidden reference chips, but PHC chips had a more intense off-odor than did LLC chips. After S16, canola chips had the lowest (P<0.001) characteristic and highest off-odor/flavor; all other chips were similar. At P16, canola, PHC, and LLC chips had slightly higher (P<0.001) characteristic odor/flavor scores than other chips. After P16 and P24, all stored tortilla chips had lower characteristic odor/flavor scores than hidden reference chips. Rancid, painty, buttery odor/flavor, and bitter flavor notes were detected in Schaal and practically stored chips. Stored chips from all oils were similar in color and crispness. The peroxide value and thep-anisidine value for oils extracted from Schaal-stored chips tended to support panelist data; results from similar analyses of practically stored chips did not. Peroxide values andp-anisidine values for stored used frying oils and the corresponding sensory data for stored chips generally did not agree. Results indicate considerable potential for increasing use of canola oil products for frying tortilla chips.     

Method for analysis of TAG formed by reaction of fish oil with hydrogenated soybean oil

An HPLC method was developed for analysis of the TAG formed during interesterification of a fish oil rich in DHA residues and of a fully hydrogenated soybean oil. TAG species were separated using a three-phase (acetone/acetonitrile/chloroform) solvent system. Peak identities were assigned on the basis of a multiple linear regression analysis by using factors such as carbon number, number of double bonds, and number of PUFA in the molecule as predictors for TAG retention time. Good agreement between experimental and predicted retention times was observed when the effect of the PUFA was separated in the regression model from that of the monounsaturated FA. In addition, the new method permits one to determine tristearin at concentrations up to 3 mg/mL without encountering the problem of partial retention of this TAG in the column that was observed when chloroform is not incorporated in the mobile phase.     

A technique for testing the reversion properties of hydrogenated soybean oil shortenings

Summary A technique has been described which was found to yield specific and reproducible evaluations of the reversion properties of shortening samples containing hydrogenated soybean oil. It was shown to be advantagenous to conduct the test by smelling rather than by tasting. The use of a control rendered the test specific and by expanding to a series of controls of varying concentrations, it was found possible to increase the discrimination of the test. The statistical method reported by Dr. Bliss (3) was used to analyze the data obtained.     

Hydroxystearic acid deposition and metabolism in rats fed hydrogenated castor oil

Groups of rats were fed diets containing corn oil, 1% hydrogenated castor oil (principal constituent: 12-hydroxystearic acid) or 10% hydrogenated castor oil. Rats were sacrificed after 4, 8, 12 and 16 weeks for determination of hydroxy fatty acids in excised abdominal adipose tissue or in lipid extracted from lyophilized carcass. Maximum content of hydroxystearic acid was 4.4% in adipose tissue of rats four weeks on the 10% hydrogenated castor oil diet. When rats on hydrogenated castor oil diets were switched to the corn oil diet, hydroxystearic acid was depleted from their tissues. 10-Hydroxypalmitic and 9-hydroxymyristic acids were characterized as metabolites of 12-hydroxystearic acid. No adverse effects of diets were observed except reduced growth in rats given 10% hydrogenated castor oil diet. Presented at the AOCS Meeting, New York, October, 1968. Western Utiliz. Res. & Dev. Div., ARS, USDA.