The pH of normal milk generally lies between 6.6 - 6.8 with average of 6.7 as the most common value. 2. “a” is the osmotic pressure of the solution. Figure 2.8. This value is true for pH measurement of milk of approximately 25 °C. Table 2.5 shows an abridged list of milk proteins according to a modern system. Theoretical values, valid under certain conditions, are pH 5.1 to 5.3. The iodine value states the percentage of iodine that the fat can bind. The latter, bacterial enzymes, vary in type and abundance according to the nature and size of the bacterial population. Milk contains approximately 3.4% total fat. Denaturation begins at 65°C and is almost total when whey proteins are heated to 90 °C for five minutes. Although casein represents 80–85% of total milk protein, when precipitation occurs, the liquid portion is referred to as whey. Composition of milk and goat's milk per 100 g of milk (Cayot, 1998) Species Proteins Casein Fat Lactose Ash Cow 3.2 2.8 3.90 0.90 to 4.9 0.90 Goat 2.8 2.3 3.38 4.4 to 04.7 0.5 to 0.8 milking time. The proximate and mineral composition of the plain cashew nut milk was analysed, as well as the physicochemical and sensory characteristics of the cashew nut milk containing sugar and vanilla … The proteins are denatured and lose their original solubility. In a neutral solution the number of [H+] per litre of the solution is 1:10 000 000 mol/l or 10–7 mol/l. The presence of phosphatase in milk can be detected by adding a phosphoric-acid ester and a reagent that changes colour when it reacts with the liberated alcohol. Enzymes do this without being consumed. The milk fat exists as small globules or droplets dispersed in the milk serum, Figure 2.15. Milk chemistry and composition - Basics for Dairy processing 1. Phospholipid Enzymes, a class of proteins whose function is to catalyse reactions, lose this ability when denatured. In many cases, however, denaturation is irreversible. For natural reasons, low-fat milk products contain less of these vitamins. Milk and cream are examples of fat-in-water (or oil-in-water) emulsions. Methional or 3-mercapto-methylpropionaldehyde is the principal contributor to sunlight flavour, as this particular flavour is called. The proteins can be classified in various ways according to their chemical or physical properties and their biological functions. Zoom Lactose can be prepared from whey, a by-product of the Such composite carbohydrates are called polysaccharides and have giant molecules made up of many glucose molecules. As the possible number of combinations of 20 amino acids in a chain containing 100 – 200 amino acids is very large the number of proteins with different properties is also very large. chalk in water) it is said to be in colloidal solution or colloidal suspension. Milk fat is a mixture of different fatty-acid esters called triglycerides, which are composed of an alcohol called glycerol and various fatty acids. Lactose is a sugar found only in milk; it belongs to the group of organic chemical compounds called carbohydrates. The protein is then precipitated from the solution. Percentage of the β - casein not associated with the micelles after keeping milk for about 24 h at varying temperature (Ref. Oxidation off-flavour is more liable to occur at low temperatures, because these bacteria are less active then. 2.40 Other microorganisms in the milk generate other breakdown pro-ducts. 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