may vary from one region to another,the basic ingredients and manufacturing are essentially consistent(p.75): 9.LA:Lactobacillus acidophilus(p.77) 10.LAB:lactic acid bacteria(p.73) 三、简述题 1.What is the Stoke's Law???(p.39)? ce in density between the two phases .decreasing viscosity of the continuous phas 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. 2.How to Separate the cream from milk?(p.39) Centrifuges can be used to separate the cream from the skim milk.The centrifuge consists of up to 120 discs stacked together at a 45 to 60 degree angle and separated by a 0.4 to 2.0 mm gap or separation channel.Milk is introduced at the outer edge of the disc stack.The stack of discs has vertically aligned distribution holes into which the milk is introduced. Under the influence of centrifugal force the fat globules(cream),which are less dens than the ski axis of 3.What is the Pasteurization of milk?(p.40) The process of pasteur aton wa name d after Louis Pasteur who discovered that applying h ing poin The process was later applied to milk and remains the most the p f od par ut allo owing recontamin milk during th e heat treatment process. 4.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 fatmay vary from one region to another, the basic ingredients and manufacturing are essentially consistent(p.75): 9. LA: Lactobacillus acidophilus(p.77) 10. LAB: lactic acid bacteria (p.73) 三、简述题 1. 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. 2.How to Separate the cream from milk?(p.39) Centrifuges can be used to separate the cream from the skim milk. The centrifuge consists of up to 120 discs stacked together at a 45 to 60 degree angle and separated by a 0.4 to 2.0 mm gap or separation channel. Milk is introduced at the outer edge of the disc stack. The stack of discs has vertically aligned distribution holes into which the milk is introduced. 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. 3. What is the Pasteurization of milk?(p.40) The process of pasteurization was named after Louis Pasteur who discovered that spoilage organisms could be inactivated in wine by applying heat at temperatures below its boiling point. The process was later applied to milk and remains the most important operation in the processing of milk. Definition: The heating of every particle of milk or milk product to a specific temperature for a specified period of time without allowing recontamination of that milk or milk product during the heat treatment process. 4. 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