The sugar is a simple type of carbohydrate and represents the main source of energy to power the biological and physical activities in the body. However, it has been reported that over weight gain, imperfect metabolic processes and heart diseases are mainly related to excess sugar intake, which causes diabetic complains. This has raised the demand of having reliable test methods for quantifying sugar amount in different samples to both monitor sugar levels and to study the biological effects of carbohydrates. This provides valuable information in various fields, including food science, biochemistry, and medicine. Several test methods have been applied to detect the presence of sugar in a biological sample. Conventional tests imply using special chemical reagents. Two well known tests are discussed briefly in this report, namely Molich’s and Fehling's tests. The chemical reagents, test procedures, precaution as well as advantages and limitations were comprehensively discussed. A comparison between the two tests has been thoroughly addressed.   

Carbohydrates, sugar quantification, diabetes

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