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Reducing Sugar: E.g. Glucose, Fructose, Lactose and Maltose
| Test | Observation | Inference |
| Few drops of the sample + Fehling’s solution + warm | Solution gives yellow precipitate, which turns brick red on warming. | Reducing sugar is present |
| Few drops of the sample + Benedict’s solution + warm | Solution gives orange red or yellow precipitate. | Reducing sugar is present |
Non non-reducing sugars do not react with Fehling’s nor Benedict’s solution. Therefore they do not give any precipitate with these reagents.
Tests for Fat and Oil
| Test | Observation | Inference |
| 2cm3 of sample + water + (3 – 5 drops of) Sudan (III) stain | Red stain is formed | Sample is melted fat or oil |
| Few drops of sample on a piece of white paper or filter paper | Translucent spot (grease spot) is observed on the paper | Sample is melted fat or oil |
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