Effect of emulsifiers and fat crystals on shear induced droplet break-up, coalescence and phase inversion
Effect of emulsifiers and fat crystals on shear induced droplet break-up, coalescence and phase inversion
复制标题
乳化剂和脂肪晶体对剪切引起的液滴破碎、聚结和相转化的影响
DOI：
10.1016/j.foodhyd.2008.09.014
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发表时间：
2009
影响因子：
10.7
通讯作者：
Norton I
中科院分区：
文献类型：
--
作者：
Norton I
我们研究了使用一系列乳化剂在动态条件下食品级乳液的破裂和聚结。不出所料，乳液的破裂随着施加的剪切而变化。具有纯化葵花油的无乳化剂系统在施加的剪切力减小后测得的聚结速率为 1.2×10−2s−1，这与非食品系统的报告值相似，但可以通过使用吐温 80 完全阻止，还使用其他表面活性剂，如明胶和吐温 20。 40% 三棕榈苷与吐温 20 或单棕榈苷的相转化是一个重要的工业过程，在没有晶体的情况下不会发生。通过调节乳化剂浓度以及晶体的运动，我们已经证明甘油三酯的结晶控制着过程动力学并最终控制相转化温度。前两种效应也有助于描述在形成食品级纳米乳液时需要过量的乳化剂。因此，我们表明，对于含有吐温 20 或吐温 80 的肉豆蔻醇乳液，决定最终液滴尺寸的是纳米乳液聚结的逆反应，而不是乳化过程的初始能量输入。
We have investigated the breakup and coalescence of food grade emulsions under dynamic conditions with a range of emulsifiers. Not unexpectedly, breakup of the emulsions varied with applied shear. The coalescence rate for an emulsifier free system with purified sunflower oil after the imposed shear was reduced, was measured at 1.2×10−2s−1, which is similar to reported values for non-food systems but could be totally arrested by the use of Tween 80, other surfactants such as gelatin and Tween 20 were also used. Phase inversion of 40% tripalmatin with either Tween 20 or monopalmatin, which is an important industrial process, was shown not to occur in the absence of crystals. By adjusting the emulsifier concentration and hence the movement of the crystals we have shown that the crystallisation of triglycerides controls the process dynamics and ultimately the phase inversion temperature. Both of the former effects also help describe the need for an excessive amount of emulsifier when forming food grade nano-emulsions. Thus, we show that with a myritol emulsion with either Tween 20 or Tween 80, it is the back reaction of nano-emulsion coalescence that determines the final droplet size and not the initial energy input from the emulsification process.
DOI：
10.1016/0255-2701(94)02000-0
发表时间：
1994-11-01
影响因子：
4.3
作者：
STANG, M;KARBSTEIN, H;SCHUBERT, H
通讯作者：
SCHUBERT, H