Determination of carotene in food (1)

1.
Determination of carotene in food

Carotene is an important nutrient needed by the body, because it can be converted in the body into vitamin A, play the role of vitamin A, also known as vitamin A former
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1.
Principle

After the sample was saponified with petroleum ether extraction of carotenoids in food and other plant pigments, in petroleum ether as eluent for paper chromatography, the polar carotenoids minimum, the fastest moving, thereby separating the other pigments
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2.
Reagents

(1) Petroleum ether (boiling range 30～60℃): It is also a developing agent
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(2) Potassium hydroxide solution (1+1): Dissolve 50g potassium hydroxide in 50g water
.

(3) Anhydrous ethanol : must not contain aldehydes
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(4) Anhydrous sodium sulfate
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(5) β-carotene standard solution: accurately weigh 50.
0 mg of β-carotene standard and dissolve it in 100.
0 mL of chloroform , the concentration is about 500ug /mL, and accurately measure its concentration
.

Where p——the concentration of β-carotene standard solution, ug/mL

A-average absorbance

E-β-carotene in n-hexane solution, the wavelength of incident light is 450nm, the thickness of the cuvette is 1cm, and the concentration of the solution is 1μg/L.

3.

(6) B-carotene standard solution: accurately dilute the calibrated standard solution 10 times with petroleum ether, so that each 1mL solution is equivalent to 50ug β-carotene, and store it in the refrigerator in the dark

3.

(1) Commonly used equipment in the laboratory

(2) Glass chromatography cylinder

(3) Spectrophotometer

(4) Rotary evaporator

(5) Constant temperature water bath

(6) Saponification reflux device
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(7) Spotter or micro syringe
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(8) Filter paper: 18cm×30cm, qualitative, fast or medium speed
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