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- To test for the presence of monosaccharides and reducing disaccharide sugars in food, the food sample is dissolved in water, and a small amount of Benedict's reagent is added. During a water bath, which is usually 4-moiety, after isomerization.
- Sucrose (table sugar) contains two sugars (fructose and glucose) joined by their glycosidic bond in such a way as to prevent the glucose isomerizing to aldehyde, or the fructose to alpha-hydroxy-ketone form. Sucrose is thus a non-reducing sugar which does not react with Benedict's reagent. Sucrose indirectly produces a positive result with Benedict's reagent if heated with dilute hydrochloric acid prior to the test, although after this treatment it is no longer sucrose. The acidic conditions and heat break the glycosidic bond in sucrose through hydrolysis. The products of sucrose decomposition are glucose and fructose, both of which can be detected by Benedict's reagent, as described above.
- Starches do not react or react very poorly with Benedict's reagent, due to the relatively small number of reducing sugar moieties, which occur only at the ends of carbohydratechains. Inositol (myo-inositol) is another carbohydrate which produces a negative test.
- Benedict's reagent can be used to test for the presence of glucose in urine. Glucose found to be present in urine is an indication of diabetes mellitus. Once a reducing sugar is detected in urine, further tests have to be undergone in order to ascertain which sugar is present. Only glucose is indicative of diabetes.
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Does skim milk test positive with the benedict's test?
yes
Will albumin give positive result to Benedict test?
No, albumin will not give a positive result to the Benedict test. The Benedict test is used to detect the presence of reducing sugars such as glucose, fructose, and maltose, not proteins like albumin.
What is the indicator and color change for a positive test for glucose?
Benedict solution is the chemical indicator for simple sugars.
Why sucrose does not give a positive Benedict's test but hydrolyzed sucrose does give a positive beneditcts test?
Sucrose does not contain a free aldehyde or ketone group needed to reduce Benedict's reagent, so it does not give a positive Benedict's test. When sucrose is hydrolyzed into glucose and fructose by acid or enzymes, the resulting glucose can then react with Benedict's reagent due to the presence of the free aldehyde group, producing a positive test result.
Will fructose give a positive benedict's test?
Yes! Fructose is a reducing carbohydrate.
Will hydrolysed dextrine give positive response to Benedict test?
Yes, hydrolyzed dextrin will give a positive response to the Benedict test as it contains reducing sugars that can react with the Benedict's reagent to form a colored precipitate indicating the presence of reducing sugars.
Do eggs test positive in benedicts test?
Yes, eggs can test positive in the Benedict's test because they contain glucose, which is a reducing sugar that reacts with the reagent in the test to form a colored precipitate.
Is it possible for a solution to test positive in Benedict's test and negative in barfoed's test?
No! Its not possible for a solution to test positive for benedict`s and test negative for barfoed `s test as both detect the presence of reducing sugars and the only difference between the two tests is that further confirmation of a mono or disaccharide is done in barfoed ` s test.
What is a positive test for carbohydrates?
These are the carbohydrate tests that would give a positive result on maltose: 1.Molisch test 2. Fehling's Test 3. Benedict's Test 4. Nylander's Test 5. Tollen's Test 6. Seliwanoff's Test 7. Barfoed's Test
Why is the Benedict test not exclusive to glucose?
The Benedict test is not exclusive to glucose because it can detect the presence of reducing sugars in general. This means that it can also detect other reducing sugars such as fructose, lactose, and maltose, in addition to glucose. The test relies on the reduction of Cu(II) to Cu(I) in the presence of reducing sugars, forming a colored precipitate.
Does starch gives positive result for Benedict test?
Yes, starch does not give a positive result for the Benedict test because starch is a complex carbohydrate composed of multiple glucose units linked together in long chains. Benedict's reagent is used to test for the presence of reducing sugars, such as glucose and fructose, which can reduce the copper ions in the reagent, causing a color change. Starch does not have the ability to reduce the copper ions in Benedict's solution.
Will mannose produce a positive Benedict's test?
Yes, mannose will produce a positive Benedict's test result as it is a reducing sugar. Benedict's reagent is used to detect the presence of reducing sugars such as glucose, fructose, and mannose by forming a reddish-colored precipitate when reacted with them.
