Improvement of physicochemical properties of reduced-cholesterol butter by the addition of β-sitosteryl oleate.

Beta-cyclodextrin (β-CD) has been shown to successfully lower the cholesterol content of dairy products, such as butter, but the process tends to negatively impact the overall quality and consistency. In this study, β-sitosterol, which is similar in structure as cholesterol, was reacted with oleic acid to form β-sitosteryl oleate (BSO), and this was used to improve the consistency of reduced-cholesterol butter. The reaction was catalyzed by sodium bisulfate (2%, w/w) at 140 °C, and the highest degree of esterification (94.3%) was obtained after 9 hr of reaction using a β-sitosterol-oleic acid molar ratio of 1:5. Ultra-pasteurized cream was then treated with 15% (w/v) β-CD at 40 °C with stirring (100 rpm), for 30 min. Results indicated a 95.4% reduction in cholesterol content. Finally, the reduced-cholesterol cream was constituted to contain 3, 5, and 10% (w/w) BSO, after which fat was extracted from the three formulations and their melting profiles compared to that of milk fat. The cream containing 3% BSO showed a profile similar to milk fat and was, therefore, used to formulate BSO-incorporated reduced-cholesterol butter (BSOB). Instrumental analyses showed that BSOB was comparable to the control butter with respect to physical properties, such as hardness/firmness and adhesiveness. PRACTICAL APPLICATION: A modified plant sterol, beta-sitosteryl oleate, was incorporated into a reduced-cholesterol butter to improve its physicochemical properties. The reduced-cholesterol butter was comparable to regular butter with respect to its consistency and melting properties and could be made into sticks. In addition to the reduced-cholesterol butter, this product could provide the foundation for new products blending butter and oils to create other low-cholesterol, reduced saturated-fat products, possibly in stick form.