proximate analysis
ABSTRACT:
Water is omnipresent in foodstuffs and the surrounding atmosphere. In principle, the moisture content of a food can therefore be determined accurately by measuring the number or mass of water molecules present in a known mass of sample. It is not possible to directly measure the number of water molecules present in a sample because of the huge number of molecules involved. A number of analytical techniques commonly used to determine the moisture content of foods are based on determinations of the mass of water present in a known mass of sample. An appreciation of the principles, advantages and limitations of the various analytical techniques developed to determine the moisture content of foods depends on an understanding of the molecular characteristics of water. The method used was with oven drying, which the sample is heated under specified conditions, and the loss of weight is used to calculate the moisture content of the sample. After the result obtained, the average percentage of moisture in doughnut sample was 42.721 2.043.
The determination of ash content in the foods helps us to know the mineral contents and their nutritional value. There are three methods in determination of ash such as dry, wet and conductometric methods. Dry method is normally used for all kinds of food but not suitable for trace metals such as arsenic, mercury or lead. All non-water soluble, water soluble and non- acid soluble ash can is determined using this method. Wet ashing method is more suitable to be used to obtain ash which will be used to determine trace metals and metallic poison. Conductometric is normally used for sugar and high sugar products such as syrup, honey and drinks. In this experiment, dry ashing method was used. The doughnut sample was burned in furnace to white ash without black particles at least 7 hours at 500-700. Crucibles containing ash were cooled in dessicator and weighed. The average percentage of ash in food sample was 7.42 0.103.
Water is omnipresent in foodstuffs and the surrounding atmosphere. In principle, the moisture content of a food can therefore be determined accurately by measuring the number or mass of water molecules present in a known mass of sample. It is not possible to directly measure the number of water molecules present in a sample because of the huge number of molecules involved. A number of analytical techniques commonly used to determine the moisture content of foods are based on determinations of the mass of water present in a known mass of sample. An appreciation of the principles, advantages and limitations of the various analytical techniques developed to determine the moisture content of foods depends on an understanding of the molecular characteristics of water. The method used was with oven drying, which the sample is heated under specified conditions, and the loss of weight is used to calculate the moisture content of the sample. After the result obtained, the average percentage of moisture in doughnut sample was 42.721 2.043.
The determination of ash content in the foods helps us to know the mineral contents and their nutritional value. There are three methods in determination of ash such as dry, wet and conductometric methods. Dry method is normally used for all kinds of food but not suitable for trace metals such as arsenic, mercury or lead. All non-water soluble, water soluble and non- acid soluble ash can is determined using this method. Wet ashing method is more suitable to be used to obtain ash which will be used to determine trace metals and metallic poison. Conductometric is normally used for sugar and high sugar products such as syrup, honey and drinks. In this experiment, dry ashing method was used. The doughnut sample was burned in furnace to white ash without black particles at least 7 hours at 500-700. Crucibles containing ash were cooled in dessicator and weighed. The average percentage of ash in food sample was 7.42 0.103.
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