Physical Chemistry of Foods

classes. We then haveNiparticles in size classiand Ni¼ Zxiþ (^12) Dx xi
^12 Dx fðxÞdðxÞð 9 : 3 Þ whereDxis the class width andxi ...

In the next part, we will for sake of simplicity consider spherical particles. The following parameters can be defined: d¼sphere ...

d 30 ¼ S 3 S 0  1 = 3 ¼volume averagediameter d 32 ¼ S 3 S 2 ¼volume/surfaceaverage;or Sauter mean, diameter d 63 ¼ S 6 S 3  ...

distribution. This type of average should be inserted into Eq. (9.1a) for a polydisperse system. The most commonly used average ...

9.3.3 Complications Many particles encountered in practice are not true homogeneous spheres, although emulsion drops and small g ...

shape factor varies considerably among individual particles. However, if average and range ofcdo not significantly vary among si ...

comparing two different methods on the same sample, one should not be surprised when the results differ by a factor of two, and ...

Accuracy. Several kinds of uncertainty can arise.Systematic errors can readily occur for indirect methods. The signal measured c ...

particles in a size class. This is largely owing to the Poisson statistics of counting. The standard deviation of the number of ...

103 times 0.01%¼ 10 %of the aqueous phase would have been contaminated with yeasts, which is not negligible. This is only a crud ...

two or more kinds of structural elements can be distinguished. Most of the aspects covered in the following chapters concern dis ...

those with large ones. External forces applied to a system have stronger effects on large particles than on small ones, which ha ...

Several chapters on microscopic and other methods of determining the physical structure of foods are in E. Dickinson, ed. New Ph ...

10 Surface Phenomena As we have seen in the previous chapter, most foods are dispersed systems, and many of the structural eleme ...

blob, it tends to assume a spherical shape, which is the smallest surface area possible for a given volume. An obvious example i ...

that it concerns a pure liquid) and are different manifestations of the same phenomenon: work has to be done to enlarge the surf ...

by which the liquid pulls at the plate and divides it by the perimeter of the plate in a plane parallel to the liquid surface. A ...

on average, the net force equals zero. This is because of the hard core repulsion between molecules. As illustrated in Figure 3. ...

here the very strong metallic bonds are responsible. The interfacial tension g 12 between two condensed phases 1 and 2 is genera ...

monolayer has been obtained (roughly speaking), no further accumulation takes place. Solutes showing this kind of behavior are c ...