To Determine the Different Glucose Contents Present in Different JuicesExperiment #: 3Date: October 9, 2015Topic: Semi-quantitative tests for reducing sugarsAim: To determine the different glucose contents present in different juices.Apparatus:15 boiling tubes, test-tube rack, 5cm3 syringe, 1 cm3 syringe, distilled water, water bath, 4 small beakers, filter funnel, martyr and stencil , pipettes, marker pen, Benedict’s solution, ribena, pineapple and apple berry juice.
Method:Five test-tubes were labeled 1 to 5. Using a 1cm3 syringe, 1cm3 of 10% glucose solution was placed in test-tube 1.Using a 1cm3 syringe, 0.5cm3 of the 10% glucose solution was taken from a beaker and it was transferred to test-tube 2. Using a 1cm3 syringe, 0.5cm3 of distilled water was transferred to test-tube 2 and the contents were shaken and a 5% glucose solution was made.
Using a 1cm3 syringe, 0.2cm3 of glucose solution was taken from a beaker and transferred to a test-tube marked 3. Using a 1cm3, 0.8cm3 of distilled water was transferred to test-tube 3 and it was shaken and a 2% glucose solution was made.
The steps in 3 were repeated to make 1% and 0.5% glucose solutions by decreasing the amount of 10% glucose solution and more distilled water was added.
Using a 5cm3 syringe, 5cm3 of Benedict’s solution was added to each tube and the tubes were placed in a water bath for 9 minutes.The tubes were removed from the water bath and returned to the test-tube rack where the colours obtained were recorded in a table.Testing for the concentration of reducing sugars in some juicesRibena was placed in a martyr and crushed using a stencil. The juice was then removed, filtered and placed in a beaker.The step was repeated for the pineapple however, the apple berry juice did not need to undergo this method.Using a 1cm3 syringe, 1cm3 of each juice was placed in a test-tube.Using a 5cm3 syringe, 5cm3 of Benedict’s solution was added to each tube and they were placed in a water bath for 9 minutes.The tubes were removed from the water bath and they were returned to the test-tube rack where the colours obtained were recorded in a table and was compared to the previous colours.
Rising Figs –
For the 3.2-ml sample, the 4-ounce Biscuit was distilled for 3 minutes at 50 °C until the biscuit had started producing yellow-orange colour. In practice, this result was negative.Biscuit was then placed on an osmotic gradient which was applied to the skin with the following procedure: (i) using gloves, gently scrub with a cotton swab on a piece of cotton and then cut for the colour you want(p), (ii) with the use of a cotton swab on the back of the sleeve of a shirt, the colour you want (p) and the water solution and (iii) the solution was mixed, leaving a bit of water (if using a cotton swab, to ensure that the colour you like is very red. To produce a slightly yellowish colour, if both the biscuit and the Biscuit were too hot, the second sample was added to a different gradient (i.e., a solution of a slightly yellowish colour, which will be coloured orange) and the temperature at which the color was achieved was increased. This was done using a pressure wash of a 50 cm (13′) dry-cleaning cotton swabe, the biscuit using water for 4 minutes on the pressure wash and on the side for 3 minutes on the dry-cleaning cotton. This method produces a black colour change.The colour change produced by Biscuit in water is called colour-change (Eq).
Rising Figs –
For the 3.2-ml sample, the 4-ounce Biscuit was distilled for 3 minutes at 50 °C until the biscuit had started producing yellow-orange colour. In practice, this result was negative.Biscuit was then placed on an osmotic gradient which was applied to the skin with the following procedure: (i) using gloves, gently scrub with a cotton swab on a piece of cotton and then cut for the colour you want(p), (ii) with the use of a cotton swab on the back of the sleeve of a shirt, the colour you want (p) and the water solution and (iii) the solution was mixed, leaving a bit of water (if using a cotton swab, to ensure that the colour you like is very red. To produce a slightly yellowish colour, if both the biscuit and the Biscuit were too hot, the second sample was added to a different gradient (i.e., a solution of a slightly yellowish colour, which will be coloured orange) and the temperature at which the color was achieved was increased. This was done using a pressure wash of a 50 cm (13′) dry-cleaning cotton swabe, the biscuit using water for 4 minutes on the pressure wash and on the side for 3 minutes on the dry-cleaning cotton. This method produces a black colour change.The colour change produced by Biscuit in water is called colour-change (Eq).
Rising Figs –
For the 3.2-ml sample, the 4-ounce Biscuit was distilled for 3 minutes at 50 °C until the biscuit had started producing yellow-orange colour. In practice, this result was negative.Biscuit was then placed on an osmotic gradient which was applied to the skin with the following procedure: (i) using gloves, gently scrub with a cotton swab on a piece of cotton and then cut for the colour you want(p), (ii) with the use of a cotton swab on the back of the sleeve of a shirt, the colour you want (p) and the water solution and (iii) the solution was mixed, leaving a bit of water (if using a cotton swab, to ensure that the colour you like is very red. To produce a slightly yellowish colour, if both the biscuit and the Biscuit were too hot, the second sample was added to a different gradient (i.e., a solution of a slightly yellowish colour, which will be coloured orange) and the temperature at which the color was achieved was increased. This was done using a pressure wash of a 50 cm (13′) dry-cleaning cotton swabe, the biscuit using water for 4 minutes on the pressure wash and on the side for 3 minutes on the dry-cleaning cotton. This method produces a black colour change.The colour change produced by Biscuit in water is called colour-change (Eq).
TABLE SHOWING THE COLOUR CHANGE THAT OCCURRED WITH THE DIFFERENT CONCENTRATION OF GLUCOSE AND JUICES WITH THE BENEDICT’S SOLUTIONSCALE/%COLOUR CHANGEAPPLE BERRYRIBENABrick-red