Vitamin C content determination.

, purpose to learn and master the principles and methods of measuring assacleic acid content in plant materials using 2,6-DPA titration.
II, Principle
Vitamin
C is one of the most important vitamins in human nutrition, and together with other reducing agents in the body to maintain the normal redox potential of cells and related enzyme system activity. Vitamin C promotes the synthesis of intercellular quality, and if the body is deficient in vitamin C, sour blood disease occurs, so vitamin C is also known as aspertic acid. Fruits and vegetables are the main sources of astrophic acid in the human body. Different cultivation conditions, different maturity and different processing and storage methods can affect the assailable acid content of fruits and vegetables. Determining astrochmic acid content is an important index to understand the quality of fruits and vegetables and
the effectiveness
processing process. 2,6-chlorophenol is a dye that is blue in an alkaline solution and red in an acidic solution. Astrophic acid has a strong reduction, can make 2,6-dechlorophenol reduced fade, the reaction is as follows:
when the use of 2,6-dechlorophenol titration contains acid solution of astrophic acid, drop The next 2,6-chlorophenol indigophenol is reduced to colorless, and when all the astrophic acids in the solution are oxidized into dehydrogenated astroviric acids, the drop of 2,6-chlorophenol indigophenol immediately makes the solution red. Therefore, the use of this dye titration astrophic acid to the solution is light red is the end point of titration, according to the consumption of dyes can be calculated in the sample also prototype astrophic acid content.
, experimental materials, major instruments and
reagents1. The experimental
take 50g samples of fresh fruits (vegetables), add 100g 2% herbal acid solution, and use
tissue
mashing machine to make a smooth slurry. Weighing 10g homogenization, move into a 50mL
capacity bottle
, with 2% sorbic acid to the scale, shake well and leave to spare.
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