Application of Mettler Toledo products in the determination of vitamin C content

Vitamin is a word we often hear. We take in a variety of vitamins through food every day. Vitamins are closely related to our health. Vitamin C (also known as ascorbic acid) is commonly found in fruits and vegetables. It is also a vital substance for humans: lack of vitamin C in the human body will lead to scurvy. Vitamin C can also prevent infectious diseases and even cancer. Therefore, the food and beverage, pharmaceutical, and medical industries all need to measure the content of vitamin C in food, beverages, medicines, and blood.

There are many methods for determining vitamin C, including redox titration using I2 or dichloroindophenol (DPI). In general, titration is a fast, simple, and accurate technique that accurately determines the content of the substance being measured through an equivalent reaction between the titrant and the titrated substance. DPI has good selectivity for vitamin C and is an ideal oxidant. The

traditional titration method is manual titration, which determines the end point according to the change in the color of the indicator and calculates the content of the substance being measured by measuring the consumption of the titrant. Manual titration has many shortcomings: manual control errors are large, calculations are complex, and special indicators are required for different reactions. Mettler-Toledo's automatic potentiometric titrator solves this problem. It determines the endpoint by measuring the change in potential during the titration reaction. It operates and calculates automatically, measures quickly, and gives accurate results. Mettler-Toledo's titrator is equipped with a memory card software package that stores mature titration methods, which can quickly and easily solve practical application problems and can be used as a new experimental method with a slight modification.

The following is an example of a beverage company using a Mettler-Toledo DL53 potentiometric titrator to determine the vitamin content in a beverage.

Sample source Sample amount Vc content Vc content Vc content Vc content RSD
g (mg/100g) a (mg/100g) b (mg/100g) c (mg/100g) d %
Kiwi fresh slices 5103.79 104.25 104.81 103.96 0.979
Orange juice 1 bottle 537.04 37.16 37.21 37.09 0.507
Orange juice 2 bottles 537.19 37.06 37.03 37.12 0.501
Orange juice 3 bottles 537.14 37.04 37.09 37.20 0.447
Avocado juice 1 bottle 541.46 41.52 41.6541.560.477
鳄梨汁2瓶装541.58 41.54 41.6441.460.434
柠檬汁1鲜榨553.00 53.18 53.1253.090.339
柠檬汁2鲜榨553.01 53.13 53.0653.180.321
柠檬汁3鲜榨553.13 53.17 52.9653.080.396
葡萄汁1瓶装1053.04 53.05 53.0453.050.022
葡萄汁2瓶装1053.03 53.06 53.0553.050.057
葡萄汁3瓶装1053.05 53.06 53.0653.040.044