Method for detecting sugar content in several common fruits

Fruit has become a necessity in our daily life. Eating fruits is good for health, and colorful fruits always keep us entertained. But the sugar in the fruit is also a well-known thing. The question is, how much sugar is contained in the fruit. This is something we care about and pay attention to. Do we have any way to check the sugar content in them?


The first thing to do is to analyze the composition of the fruit. As the name suggests, most of the fruits, even 99% of them should be water, so the solids inside can be neglected. In the process of calculation, the fruit right is treated as sugar water. Since the sugar in the fruit is mostly in the form of glucose fructose, the sugar content and the soluble solid matter can be equalized, after all, the vitamin and mineral content is extremely small.

I went to the local supermarket to buy four kinds of fruits: apple, orange, pear and grape. It is a representative sugary fruit that is common in the north. The sugar content of the laboratory was tested using the existing instrument ATAGO Benchtop Brix meter.

Juice extraction

Extraction with a juicer is most convenient. I used a knife to cut a piece of fruit on the fruit, pressed the juice with a garlic press, dripped the juice into a small beaker, and then used the Pasteur pipette to absorb the juice supernatant for testing. The instrument used was an Atago-5000a Abbe refractometer, which was zeroed and calibrated with water and atago-equipped standard before testing.



Testing process

The supernatant juice is dripped into the detector window of the Atago-5000a Abbe refractometer, and then the detector is covered. The instrument has an automatic temperature control function. When the temperature reaches 20 degrees Celsius, press the start to read. The number read can be approximated as the amount of sugar in the fruit. The results of the test are as follows:

Four fruit sugar scales

Experimental results
As can be seen from the above table, the sugar content of apples is lower, and the highest sugar content in grapes is also in line with our perception of fruits. Therefore, diabetic patients should try to eat less juicy fruits. Apples and pears are relatively healthy fruits with low sugar content and are suitable for the consumption of ordinary people. The analysis of instruments in life is actually a lot. As long as we are the people of life, the laboratory can be used for us.