Science Buddies: "Ask an Expert"

[[Posting on behalf of student/family]]

My daughter completed the experiment utilizing glucose test kit from the website to measure glucose in beverages. We tested whole milk, Fairlite Milk (50% less sugar) , Orange Juice not from concentrate, Orange Juice not from concentrated (59% less sugar), Diet Coke, Coke, and water. All tested positive for glucose to some degree (except water of course). We expected Coke but why the others? We repeated the experiment on each beverage 3x and also diluted the Coke because it popped prior to 30 seconds, per the instructions.

Also: Is the 4 grams glucose in 200 ml solution the same amount that pops when actually testing urine? What is the significance of this particular ratio in connection to bodily fluid concentrations?

Project directions: https://www.sciencebuddies.org/science- ... se-in-food

Hi!

That's an interesting observation! Glucose is a simple sugar that can occur naturally in foods, such as milk and fruit juices. In addition, the presence of glucose in these beverages might be due to added sugars or in the case of milk, lactose. Whole milk contains lactose, a sugar that is a combination of glucose and galactose. Even though there may be less sugar in the Fairlite milk and orange juice, there is still some natural sugar that is being detected. Interestingly, there was still glucose detected in the Diet Coke. This beverage does not have added sugars. Instead, it has artificial sweeteners however, there may be a small amount that was detected due to other ingredients in the soda.

The 4 grams glucose in 200 ml solution (2% glucose) was used to set a control so that you could see the color change on the glucose strips with a sample where the amount of glucose was known. In terms of its connection to testing urine and bodily fluid concentrations, this concentration is much higher than typical urine samples. Under normal conditions, urine has a very low concentration of glucose, typically less than 0.1%

I hope that helps!