I used the DNS method below for estimation of reducing sugar in maize flour but I'm having problem with step 3 because it took more than 13hrs to evaporate the ethanol. Is there any modified method that can be use for extraction
Procedure
1. Take clean and dry test tubes and mark all the tubes as per the protocol.
2. Weigh 100 mg of the sample and extract the sugars with hot 80% ethanol twice (5 ml each time).
3. Collect the supernatant and evaporate it by keeping it on a water bath at 80°C.
4. Add 10 ml water and dissolve the sugars.
5. Take out 0.5 to 3 ml of the extract in test tubes and equalize the volume to 3 ml with water in all the tubes.
6. Add 3 ml of DNS reagent.
7. Heat the contents in a boiling water bath for 5 min.
8. Add 1 ml of 40% Rochelle salt solution when the contents of the tubes are warm.
9. Cool and read the intensity of dark red colour at 510 nm.
10. Run a series of standards using glucose (0–500 mg) and plot a graph, of concentration of glucose v/s absorbance at 630 n
Thank you sir for the document. I find the DNS method simpler. I'm hoping I could get modified method of it used for flour sample
- Badges
- Science topic