Susan L. Cuppett

Fuel properties of tallow and soybean oil esters

Fuel properties of beef tallow, soybean oil, their esters, and blends with No. 2 diesel fuel and ethanol were determined. Fuel properties tested were viscosity, specific gravity, API gravity, distillation ranges, calculated cetane index, energy content, flash point, water content, sulfur content, carbon residue, particulate matter, acid value, copper-strip corrosion test, ash content, melting point, cloud point, and pour point. Gas-chromatographic analyses of tallow, soybean oil, and their esters were performed to determine their major constituents. Viscosities of soybean oil and tallow were significantly reduced by esterification. Other fuel properties of the esters and their blends with No. 2 diesel fuel and ethanol were similar to the properties of No. 2 diesel fuel.

Cast Films from Soy Protein Isolates and Fractions

ABSTRACT Glycerol-plasticized soy protein films were cast from alkaline aqueous film-forming solutions of laboratory-prepared 7S, 11S, and soy isolate (LSI) fractions and from commercial soy isolate (CSI). Tensile strength (TS), elongation at break (E), water vapor permeability (WVP), total soluble matter (TSM), protein solubility (PS), and Hunter L, a, and b color values of these films were determined. The 11S films had greater TS than 7S films (P 0.05). The 7S films had higher TSM and PS values than 11S films (P < 0.05). CSI films were significantly darker (lower L value) and more yellow (greater positive b value) than LSI films (P < 0.05).

Development and application of multicomponent edible coatings and films: a review.

Combining the advantages of polysaccharides, proteins and/or lipids offers multicomponent edible films and coatings good mass transfer barrier properties. Multicomponent edible films and coatings could be beneficial to the food industry by leading to innovative applications. The barrier properties of these systems strongly depend upon their structure and chemistry, the interaction between different film components as well as surrounding environment conditions. Future researches on these multicomponent systems need to concentrate on the following goals: (1) investigation of the optimal film compositions and specific film-forming conditions for different food systems; (2) study of the film responses in their barrier properties to environmental factors such as RH and temperature; (3) fundamental research of the mechanism of mass transfer and the interaction of different films components and foods; (4) exploration of the feasibility of potential applications in the food industry.

Policosanol Contents and Composition of Grain Sorghum Kernels and Dried Distillers Grains

ABSTRACT Grain sorghum can be a major source of policosanols, long-chained alcohols, that have beneficial physiological activities. Sorghum dried distillers grains (DDG), a by-product of ethanol production from grain sorghum, contain a large amount of policosanols. Content and composition of policosanols in long-chained lipids extracted from grain sorghum kernels and DDG were determined. Long-chained lipids were extracted using hot hexane or hot ethanol. The major components of the long-chained lipids extracted from grain sorghum kernels, as determined using HPLC, were policosanols (37–44%), aldehydes (44–55%), and acids (4–5%). Long-chained lipids from DDG contained 52% policosanols, 23% aldehydes, 6.4% acids, and 17% wax esters/steryl esters. Composition of policosanols in DDG matched the composition in grain sorghum kernels, as determined by gas chromatography, even though the content of policosanols in DDG was greater than the content in grain sorghum kernels. Policosonal composition ranges were 0–1% ...

HPLC of grain sorghum wax classes highlighting separation of aldehydes from wax esters and steryl esters

This study was performed to develop HPLC methods for determining the composition of grain sorghum wax using a silica column and an ELSD. The method development emphasized separation of aldehydes from wax esters (WE) and steryl esters (SE). Gradient mobile systems using 0.2% (v/v) acetic acid and 0.02% (v/v) methyl tert-butyl ether (MTBE) in hexane and 0.2% (v/v) acetic acid in MTBE or hexane and 0.2% (v/v) acetic acid in MTBE separated aldehydes, acids, and alcohols, as well as minor components such as mixtures of WE and SE, and triacylglycerols (TG). Grain sorghum wax was composed of 46. 3% (w/w) fatty aldehydes, 7.5% fatty acids, 41.0% fatty alcohols, 0.7% hydrocarbons, 1.4% WE and SE, and 0.9% TG, based on HPLC data. The gradient HPLC systems were also useful for compositional analysis of carnauba wax. Carnauba wax contained of 34.3% (w/w) WE, 5.1% fatty acids, undetermined amount of fatty alcohols, and 3.0% TG.

The effects of bleached and unbleached rosemary oleoresins on light-sensitized oxidation of soybean oil

Bleached and unbleached forms of a rosemary oleoresin (RO) in stripped and nonstripped soybean oil behave both as antioxidant and prooxidant in a light-induced oxidative system. At 0.02 and 0.05% levels, RO had the greatest antioxidant activity, while at 0.01 and 0.5% levels it had the highest prooxidant activity in both stripped and nonstripped soybean oil. Treatment of both soybean oil systems with tertiary butylhydroquinone controlled light-induced oxidation of the oil better than did the oleoresin treatments. The prooxidant activity of the 0.5% RO level was probably due to an excess of prooxidant components being carried into the oil at that level, whereas the reduced antioxidant activity at 0.01% was probably due to the low initial level of active antioxidant components being added to the oil.

Near-infrared spectroscopic determination of degradation in vegetable oils used to fry various foods.

Near-infrared (NIR) spectroscopic methods for measuring degradation products, including total polar materials (TPMs) and free fatty acids (FFAs), in soy-based frying oil used for frying various foods have been successfully developed. Calibration models were developed using forward stepwise multiple linear regression (FSMLR) and partial least-squares (PLS) regression techniques and then tested with an independent set of validation samples. The results show that the quality of oil used for frying different foods can be measured with a single model. First-derivative treatments improved results for TPM measurement. In addition, PLS models gave better prediction results than FSMLR models. For PLS models, the best correlations (r) between the NIR-predicted data and the chemical method data for TPMs and FFAs in oils were 0.995 and 0.981, respectively. For FSMLR models, the best r values for TPMs and FFAs in oils were 0.993 and 0.963, respectively.

Crystallization characteristics of methyl tallowate and its blends with ethanol and diesel fuel

Methyl tallowate was prepared from edible beef tallow via transesterification, and was blended with ethanol and/or No.2 diesel fuel in different ratios. Crystallization characteristics of methyl tallowate and its blends were studied at temperatures ranging from 22 to −16°C. Blending ethanol with methyl tallowate reduced crystal formation at all temperatures. As the temperature of the blends was reduced from 22 to 0°C, there was no effect on crystal formation of saturated vs. unsaturated fatty acids. Below 0°C, the saturated fatty acids crystallized at a much faster rate than the unsaturated fatty acids.

Antiproliferation Properties of Grain Sorghum Dry Distiller's Grain Lipids in Caco-2 Cells

Antiproliferative properties of lipids extracted from grain sorghum (GS) dry distillers grain (DDG) were analyzed to determine the feasibility of developing GS coproducts as a source for human health dietary ingredients. The lipid extract of GS-DDG was delivered to human colon carcinoma (Caco-2) cells by solubilizing 0-1000 microg/mL of GS-DDG lipids in 100 microg/mL increments with micelles. A significant reduction in cell viability (25-50%) resulted at treatment levels of 400-1000 microg/mL GS-DDG lipids (p < 0.05). Alternatively, total protein levels of cells treated with 400, 500, and 600 microg/mL of GS-DDG lipid were not significantly different from the control, indicating cell growth during the treatment period. Total cell counts for the control were not significantly different from the GS-DDG lipid treated cells, but dead cell counts increased by approximately 10% for the latter sample with a concomitant increase of the intercellular protein lactate dehydrogenase leakage (30-40%) in the medium. Preliminary analysis by the fluorescence-activated cell method (FACs) demonstrated that nonviable cells were in either the early apoptotic, late apoptotic, or necrotic stage post-treatment with 400, 500, and 600 microg/mL GS-DDG lipids. Physiochemical characterization of the GS-DDG lipids used for the antiproliferation study showed the presence of vitamin E (predominantly gamma-tocopherol), triacylglycerides (predominantly linoleic acid), policosanols, aldehydes, and sterols (predominantly campesterol and stigmasterol), each of which or as synergistic/additive group of constituents may be responsible for the antiproliferative effect.

Effects of bleached and unbleached rosemary oleoresin and rosmariquinone on light-sensitized oxidation of soybean oil

Synthetic rosmariquinone (RQ), an antioxidant naturally present in rosemary (Rosmarinus officinalis L.), tertiary butylhydroquinone (TBHQ) and rosemary oleoresin (bleached and unbleached), was tested for antioxidant activity in stripped and nonstripped soybean oil in a light-induced oxidation system. In the stripped soybean oil system, RQ was significantly less (P<0.05) effective than TBHQ at controlling oxidation of the oil. In light-induced oxidation of nonstripped soybean oil, RQ had significantly lower (P<0.05) peroxide values (PV) than TBHQ after 36 h. RQ had PV that was significantly (P<0.05) lower than those for both the bleached and nonbleached rosemary oleoresin throughout the 72-h study.