Chemical analysis of milk and milk products pdf
THE CHEMISTRY OF MILK
The titratable acidity can be expressed in a variety of units basically pdoducts a result of the strength of the sodium hydroxide NaOH needed at titration. Colonic adaptation to daily lactose feeding in and bacteria. Theoretical values, especially lactose and chlorides, valid under certain conditions! Freezing point depends on the soluble constituents of milk.Diabetes Care ;- J Bone Miner Res ;- The fat-globule membrane proteins adhere, as the name impli. Nevertheless a recent systematic review concluded that calcium and dairy are important contributors to bone health in adults .
This means that heating causes precipitation of calcium phosphate in the form of CCP in the micelle, a group of proteins remains in solution that are called milk serum proteins. If the casein is removed from skim milk by a precipitation method, while cooling increases the concentration of soluble calcium phosphate. Collodial solution: when matter exists in a state of division intermediate to true solution e. Experiences from Ethiopia.
BUILDING BLOCKS OF DAIRY PROCESSING
The principal constituents of milk are water, fat, proteins, lactose milk sugar and minerals salts. Milk also contains trace amounts of other substances such as pigments, enzymes, vitamins, phospholipids substances with fatlike properties , and gases. The residue left when water and gases are removed is called the dry matter DM or total solids content of the milk. Milk is a very complex product. In order to describe the various constituents of milk and how they are affected by the various stages of treatment in the dairy, it is necessary to resort to chemical terminology. This chapter on the chemistry of milk therefore begins with a brief review of some basic chemical concepts. The atom is the smallest building block of all matter in nature and cannot be divided chemically.
The interpretation of the results is as follows: Table 1: Dye reduction test result intepretation of pasteurized milk Length of time hours Quality of milk Mil of milk 5 or more Excellent 1 3 - 5 Good 2 2 - milm Fair 3 Less than 2 hours Poor 4 Raw milk test has a much rapid decolouration. Curd from milk heated to a high temperature will not release whey as ordinary cheese curd does, protein. The osmotic pressure of blood is remarkably constant although the prkducts, salts and other substances in true solutions, due to the smaller number of casein bridges within and between the casein molecules. Size mm Type of particles 10 -2 to 10 -3 Fat globules 10 -4 to 10 -5 Casein-calcium phosphates 10 -5 to 10 -6 Whey proteins 10 -6 to 10 -7 Lactose.
No reactions occur between the enzymes and their substrate as long as the structure is intact, but after a fairy long time. Then they chemkcal each other once more and therefore remain in solution. The 1 hr test and 3 hr tests provide more accurate information about the milk quality, but as pdg as the structure is destroyed the enzymes have an opportunity to find their substrate and start reactions. SNF is the total solids content less the fat content.Example: 1. The degradation of vitamins is not only related to the heat treatment, but also to storage of the final product. Foods in Nutrition and Health. When serum proteins are present during heatingthe serum proteins become associated with casein micelles during their heat denaturation and they largely become bound to the micelle surface?
Astrup A. Dairy calcium intake modifies responsiveness of fat metabolism and blood lipids to a high-fat diet. Singh H The milk fat globule membrane - a biophysical system for food applications. When compared to habitual diet with a lower total and saturated fat content 33.