Under the influence of centrifugal force the fat globules(cream),which are less dense than the skim milk,move inwards through the separation channels toward the axis of rotation.The skim milk will move outwards and leaves through a separate outlet. 2.How to standardize the milk?(p.40) The strem of skmnd cremecomndospfied fat content.This an be don etely cl d. dis em ou r c hing fa sare dis di come basic standardizatio nass pro ride the nce and Pearson sa approach can be viewed he 3.What is the Stoke's Law ???(p.39)? Centrifugation is based on Stoke's Law.The particle sedimentation velocity increases with: ·increasing diameter increasing difference in density between the two phases decreasing viscosity of the continuous phase If raw milk were a wed to stand the fat n a phenomena called erean mg on n.In of milk fat from the skim 4 What is the Continuous method of Pasteurization of milk?(p.42) Continuous process method has several advantage over the vat method the mos important being time and energy saving.For most continuous rocessing a high temperature short time (HTST)pasteurizer is used.The heat treatment is accomplished using a plate heat exchanger.This piece of equipment consists of a stack of corrugated stainless steel plates clamped together in a frame.There are several flow patterns that can be used.Gaskets are used to define the boundaries of the channels and to prevent leakage.The heating medium can be vacuum steam or hot water. 5.What is the Batch method of Pasteurization of milk?(p.42) vat pasteurizer whic I the vat the mik isheated and hh riod while being T k he ed in t ed hng he holdi o iUnder the influence of centrifugal force the fat globules (cream), which are less dense than the skim milk, move inwards through the separation channels toward the axis of rotation. The skim milk will move outwards and leaves through a separate outlet. 2. How to standardize the milk?(p.40) The streams of skim and cream after separation must be recombined to a specified fat content. This can be done by adjusting the throttling valve of the cream outlet; if the valve is completely closed, all milk will be discharged through the skim milk outlet. As the valve is progressively opened, larger amounts of cream with diminishing fat contents are discharged from the cream outlet. With direct standardization the cream and skim are automatically remixed at the separator to provide the desired fat content. Some basic standardization problems including mass balance and Pearson square approach can be viewed here. 3. What is the Stoke's Law ???(p.39)? Centrifugation is based on Stoke's Law. The particle sedimentation velocity increases with: • increasing diameter • increasing difference in density between the two phases • decreasing viscosity of the continuous phase If raw milk were allowed to stand, the fat globules would begin to rise to the surface in a phenomena called creaming. Raw milk in a rotating container also has centrifugal forces acting on it. This allows rapid separation of milk fat from the skim milk portion and removal of solid impurities from the milk. 4 What is the Continuous method of Pasteurization of milk?(p.42) Continuous process method has several advantages over the vat method, the most important being time and energy saving. For most continuous processing, a high temperature short time (HTST) pasteurizer is used. The heat treatment is accomplished using a plate heat exchanger. This piece of equipment consists of a stack of corrugated stainless steel plates clamped together in a frame. There are several flow patterns that can be used. Gaskets are used to define the boundaries of the channels and to prevent leakage. The heating medium can be vacuum steam or hot water. 5. What is the Batch method of Pasteurization of milk?(p.42) The batch method uses a vat pasteurizer which consists of a jacketed vat surrounded by either circulating water, steam or heating coils of water or steam. In the vat the milk is heated and held throughout the holding period while being agitated. The milk may be cooled in the vat or removed hot after the holding time is completed for every particle. As a modification, the milk may be partially heated in