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ABSTRACT: Because of the positive health effects of phytosterols, phytosterol-enriched foods and foods containing elevated levels of natural phytosterols are being developed. Phytosterol contents in cereals are moderate, whereas their levels in the outer layers of the kernels are higher. The phytosterols in cereals are currently underutilized; thus, there is a need to create or identify processing fractions that are enriched in phytosterols. In this study, pearling of hulless barley and rye was investigated as a potential process to make fractions with higher levels of phytosterols. The grains were pearled with a laboratory-scale pearler to produce pearling fines and pearled grains. Lipids were extracted by accelerated solvent extraction, and nonpolar lipids were analyzed by normal-phase HPLC with ELSD and UV detection. Total sterol analyses were performed by GC. After a 90-s pearling, the amounts of pearling fines from hulless barley and rye were 14.6 and 20.1%, respectively, of the original kernel weights. During pearling, higher levels of phytosterols and other lipids were fractionated into the fines. The contents of free sterols and sterols esterified with FA in the fines were at least double those in the whole grains. Pearling fines of hulless barley and rye contained >2 mg/g phytosterol compounds, which makes them a good source of phytosterols and thus valuable raw materials for health-promoting foods.
Paper no. L9521 in Lipids 39, 783-787 (August 2004).
Phytosterols are being studied extensively because of their positive health effects. Research projects have focused on their biological functions, safety, and chemical and physical properties, as well as on attempts to develop new phytosterolenriched foods (1,2). As the result of a recent workshop on sterols and stanols with 26 leading researchers as participants (i.e., the Stresa Workshop), an extensive review was published on the effects of using phytosterols and stanols to control serum cholesterol and the safety of phytosterol and stanol enrichments in foods (3). The authors concluded that daily consumption of 2 g of sterols or stanols decreases serum LDL cholesterol levels by approximately 10%.
Cereals are considered to be a good source of dietary phytosterols. Although their levels in whole grains are moderate (0.4-1.2 mg/g) (4,5), the total amount of phytosterols is significant because of the large amounts of cereals consumed. Phytosterols, like many other bioactive compounds...