RBO supplementation at ca. 50% total fat intake improved lipoprotein pattern in mildly hypercholesterolemic men. Methylated sterols in gamma-oryzanol are thought to be largely ineffective at inhibiting dietary cholesterol absorption, but could enhance cholesterol-lowering ability of 4-desmethylsterols. Assuming all ferulated sterols become de-ferulated in the gut, low and high gamma-oryzanolcontaining RBOs provided intestinal loads of 453 and 740 mg/d free 4-desmethylsterols, respectively. This intestinal load of 453-740 mg/d of efficacious free plant sterol equivalents had identical effects on lipoproteins.

The fatty acid composition, tocopherol and tocotrienol content, and oxidative stability of petroleum benzene-extracted Gevuina avellana Mol (Proteaceae) seed oil were determined. Positional isomers of monounsaturated fatty acids were elucidated by gas chromatography-electron impact mass spectrometry after 2-alkenyl-4,4-dimethyloxazoline derivatization. This stable oil (Rancimat induction period at 110°C: 20 h) is composed of more than 85% monounsaturated fatty acids and about equal amounts (6%) of saturated and polyunsaturated (principally linoleic) fatty acids. Unusual positional isomers of monounsaturated fatty acids, i.e., C 16:1 ∆ 11 , C 18:1 ∆ 12 , C 20:1 ∆ 11 , C 20:1 ∆ 15 , C 22:1 ∆ 17 , and presumably C 22:1 ∆ 19 were identified. The C 18:1 ∆ 12 and C 22:1 ∆ 19 fatty acids are described for the first time in G. avellana seed oil. While only minute quantities of α-, γ-tocopherols and β-, γand δ-tocotrienols were found, the oil contained a substantial amount of α-tocotrienol (130 mg/kg). The potential nutritional value of G. avellana seed oil is discussed on the basis of its composition. FIG. 1. Flame-ionization detection (FID) gas chromatogram for the fatty acid methyl ester (FAME) mixture of Gevuina avellana seed oil.

An ultrasonic technique was developed to study the crystallization process of edible fats on-line. A chirp wave was used instead of the conventional pulser signal, thus achieving a higher signal-to-noise ratio. This enabled measurements to be made in concentrated systems [~20% solid fat content (SFC)] through a 8.11-cm thick sample without significant signal loss. Fat samples were crystallized at 20, 25, and 30°C at a constant agitation rate of 400 rpm for 90 min. The crystallization process was followed by ultrasonic spectroscopy and a low-resolution pulsed nuclear magnetic resonance spectrometer. Specific relationships were found between ultrasonic parameters [integrated response, time of flight (TF), and full width half maximum] and SFC. TF, which is an indirect measurement of the ultrasonic velocity (v), was highly correlated to SFC (r 2 > 0.9) in a linear fashion (v = 2.601 SFC + 1433.0).Paper no. J10957 in JAOCS 82, 305-312 (May 2005). KEY WORDS:Full width half maximum, integrated response, p-NMR, solid fat content, time of flight, ultrasonic velocity.Sensing and measurement of food properties is crucial to the improvement of the quality of food and profitability of food manufacturing operations. Instrumental measurements can reduce the dependence on time-consuming chemical and sensory analysis. Measurements should provide some information about the food (e.g., temperature, composition, structure, concentration) that will be useful in controlling final product quality. The response time is crucial, so although laboratory tests on finished product are valuable, measurements made on-line of the freshly made or in-process foods are better. On-line sensors used in the food industry must also be inexpensive and robust to survive in the frequently hot and wet environment of a food-processing plant. The technique should also be both nondestructive and amenable to hygienic design principles (ideally, noninvasive). It should also provide a relatively simple output to an operator or an automated control system (1). Ultrasonic technology has advantages over many techniques because it can be applied to systems that are optically opaque, concentrated, and electrically nonconducting. In addition, ultrasonic measurements are rapid and precise, are nondestructive and noninvasive, can be fully automated, are nonhazardous, and are particularly suitable for on-line monitoring.Ultrasound techniques exploit the interaction of high-frequency sound with matter to generate information about material physicochemical properties. Such techniques have been established and used in numerous fields such as medicine, oceanography, and materials science. A number of publications have demonstrated the usefulness of ultrasound in food research, including particle size determination, creaming, crystallization, and aggregation phenomena in emulsions (2,3). Ultrasound also has been used to characterize the rheological behavior of solid fat dispersions and xanthan/sucrose mixtures (4,5) and to calculate the percentage of frozen material in foods...