Fribourg J L
Ann Nutr Aliment. 1978;32(2-3):617-30.
A water-in-oil emulsion with IMF behavior has been studied within DGRST Grant Nr. 75-7-0406. The dispersion of a sirupy aqueous phase of known aw into a more or less hardened fatty continuous phase was looked into through its effects, particularly how the fatty phase would modify the water behaviour of the dispersed aqueous phase. The emulsion was conventionally prepared by a preemulsion of the syrup into the lecithinated fat, an homogeneisation till enough dispersion and a centrifugation to get rid of free fat. Lecithin has to promote sufficient fat incorporation, correct dispersion and a final viscosity allowing pumpability. To get a cold centrifugate of enough consistency implies an efficient dispersion but before all a judicious choice of the continuous fatty phase, making allowance of organoleptic properties and shelf-life stability. The water behaviour has been worked at on two model systems, of initial phase volume phi = 0,36, with an internal phase made of partially inverted sucrose syrup (aw = 0,79) and an external fatty phase of either refined soybean oil or hydrogenated palm oil (m.p. 42 degrees C). These models respectively retained after centrifugation 12,5 p. 100 oil and 19,5 p. 100 fat; sorption-desorption isotherms were determined by the saturated salt solution method both at 37 degrees C and room temperature, exhibiting that the solid fat content of the continuous fatty phase positively reduces the water transfer velocity from-and-into the syrup. Such a W/O emulsified structure with a prevalent internal aqueous behaves like a pasty IMF, inherently protected against outside relative humidity variations; it also leads the system to a better consistency.
在DGRST资助项目编号75 - 7 - 0406下,对一种具有中间相行为的油包水乳液进行了研究。将已知水分活度(aw)的糖浆状水相分散到或多或少硬化的脂肪连续相中,并研究其效果,特别是脂肪相如何改变分散水相的水行为。该乳液通常通过将糖浆预乳化到经卵磷脂处理的脂肪中,进行均质直至充分分散,然后离心以去除游离脂肪来制备。卵磷脂必须促进足够的脂肪掺入、正确的分散以及最终具有可泵送性的粘度。要获得具有足够稠度的冷离心产物意味着要进行有效的分散,但首先要明智地选择连续脂肪相,同时要考虑感官特性和货架期稳定性。在两个初始相体积φ = 0.36的模型体系上研究了水行为,其内部相由部分转化的蔗糖糖浆(aw = 0.79)组成,外部脂肪相为精制大豆油或氢化棕榈油(熔点42摄氏度)。这些模型在离心后分别保留了12.5%(质量分数)的油和19.5%(质量分数)的脂肪;通过饱和盐溶液法在37摄氏度和室温下测定了吸附 - 解吸等温线,结果表明连续脂肪相的固体脂肪含量能正向降低水在糖浆中的进出转移速度。这种具有普遍内部水相的油包水乳化结构表现得像一种糊状中间相,本质上能抵御外界相对湿度的变化;它还使体系具有更好的稠度。