Physical Chemistry of Foods
lactose. In Figure 15.5c, the shapes indicated from left to right in fact represent a series of crystals grown at increasing con ...
15.2.3 Overall Crystallization Rate In practice, one is generally not so much interested in the linear growth rate LCas in the a ...
For the case of (hypothetical) spherical crystals and reaction-limited crystallization, the Avrami equation takes the form jðtÞ¼ ...
spherical crystals and takingJ(lnb) from independent measurements. It is seen that the results almost fit a single curve, as is ...
Agitation also tends to decrease the width of the crystal size distribution, because local variation in supersaturation is reduc ...
15.3.1 Ice Solidification. When pure water is cooled to below 0 8 C and heat is continuously removed, all of the water will crys ...
density of ice is lower, as explained above. Also the strong increase of the viscosity of water at decreasing temperature, despi ...
consequences for foods will be discussed in Section 16.3. Another consequence of the density difference is that dispersed ice cr ...
At high solute concentration and low temperature, the viscosity of the system may be greatly enhanced, whereby the diffusion coe ...
formed at the crystal surface. This is a kind of roughening, though at a much larger scale than the roughening phenomena discuss ...
the line these phases are in equilibrium with each other. The diagram shows four different phases and five regions. The region b ...
Suppose now that we evaporate water from the initial system to reach point B. Cooling then causes the formation of fructose?2H 2 ...
Consider now curve S for asolutionof one compound, e.g., a sugar, in water. The heat capacity will generally differ somewhat fro ...
The situation becomes more complicated when more solutes and especially when particulate material is present. It is not uncommon ...
mixture of 80%glucose at 40 8 C, part (about 30%) of the glucose will be crystalline, and that asa-monohydrate. When increasing ...
diagram into various domains. For a supersaturation ratiob <1, the solution is undersaturated and no crystallization will occ ...
b-lactose can crystallize, and their (estimated) solubility curves are given in Figure 15.17b (broken lines). The solid lines gi ...
Answer As shown in Figure 15.17, lactose needs a much higher supersaturation for reasonably fast nucleation to occur than sucro ...
coalescence of aqueous droplets in butter and margarine, and partial coalescence in some O–W emulsions (see Section 13.5). Visua ...
Pure Triglycerides. To understand something of natural fat crystallization, we need to know some properties of pure triglyceride ...
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