Experiment 3 of General Biology I
EXPERIMENT 3: IDENTIFICATION OF FOOD CONSTITUENTS IN MILK.
INTRODUCTION:
In this experiment two milk samples are given and its compositions are tested using different methods such as using benedict solution to test the presence of reducing sugar, using copper II sulphate to test the presence of protein, using K3( to test the presence of fat. However in this experiment, not only are the milk tested for its composition, the amount of the particular substance such as reducing sugar, protein and fat is also tested by observing the intensity of the colour change. Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother 's antibodies to the baby and can reduce the risk of many diseases in the baby. Milk derived from cattle species is an important food. It has many nutrients. Milk has a pH ranging from 6.4 to 6.8, making it slightly acidic (William H. Bowen and Ruth A. Lawrence, 2005).About 87% of milk is water, in which the other constituents are distributed in various forms such as solids (13%), lactose (4.8%), lipids (4%), proteins (3.4%) and minerals (0.8%). However, the quantities of the main milk constituents can vary considerably depending on the individual animal, its breed, stage of lactation, age and health status. (Frank O 'Mahony, March 1988)
Milk fat is a mixture of triacyl glycerides. There are also neutral lipids, fat-soluble vitamins and pigments (e.g. carotene, which gives butter its yellow colour), sterols and waxes. Fats supply the body with a concentrated
OBJECTIVES:
To investigate on the composition of two different types of unknown milk,
K1 and K2.
To investigate a small volume of dye, K3 this stains fats red.
To investigate the reducing sugar and protein concentrations in both sample of milk, K1 and K2.
To compare the composition of two different
INTRODUCTION:
In this experiment two milk samples are given and its compositions are tested using different methods such as using benedict solution to test the presence of reducing sugar, using copper II sulphate to test the presence of protein, using K3( to test the presence of fat. However in this experiment, not only are the milk tested for its composition, the amount of the particular substance such as reducing sugar, protein and fat is also tested by observing the intensity of the colour change. Milk is a white liquid produced by the mammary glands of mammals. It is the primary source of nutrition for young mammals before they are able to digest other types of food. Early-lactation milk contains colostrum, which carries the mother 's antibodies to the baby and can reduce the risk of many diseases in the baby. Milk derived from cattle species is an important food. It has many nutrients. Milk has a pH ranging from 6.4 to 6.8, making it slightly acidic (William H. Bowen and Ruth A. Lawrence, 2005).About 87% of milk is water, in which the other constituents are distributed in various forms such as solids (13%), lactose (4.8%), lipids (4%), proteins (3.4%) and minerals (0.8%). However, the quantities of the main milk constituents can vary considerably depending on the individual animal, its breed, stage of lactation, age and health status. (Frank O 'Mahony, March 1988)
Milk fat is a mixture of triacyl glycerides. There are also neutral lipids, fat-soluble vitamins and pigments (e.g. carotene, which gives butter its yellow colour), sterols and waxes. Fats supply the body with a concentrated
OBJECTIVES:
To investigate on the composition of two different types of unknown milk,
K1 and K2.
To investigate a small volume of dye, K3 this stains fats red.
To investigate the reducing sugar and protein concentrations in both sample of milk, K1 and K2.
To compare the composition of two different
References: Fox, P. F. Advanced Dairy Chemistry, Vol. 3: Lactose, Water, Salts and Vitamins. 2nd ed. Chapman and Hall: New York, 1995. http://www.studymode.com/essays/Identification-Of-Food-Constituents-In-Milk-1184039.html