[McCoy]

Hello ladies and gentlemen,
I'm trying to determine the 'amount' of ascorbic acid in orange and cabbage;
Standardisation
I prepared approx 0.1072mg/mg ascorbic acid solution and titrated 10ml aliquot with 8.2ml of DCPIP. To determine the mg of ascorbic that has reacted with 1mL DCPIP, I a little calculations and got approx 0.01mg . Is that correct?

Samples
Orange: 20mL diluted to 100ml then 10mL aliquot of that  requires 9ml DCPIP. My calculation: ascorbic acid is 482.4mg/L of orange juice.Anyone happy with that?
Cabbage: this is the part that has bothered me; okay. i have 50g of cabbage, add 210g of metaphosphoric acid and blend it. i took 40g of the extract and centrifue and pour the "liquot" into 200mL vol flask and fill it to the mark with metaphosphoric acid. 10mL aliquot of that requires 1mL DCPIP.
Now this is what i did: mass mg of ascorbic acid is 0.01(see above)*1ml(dcipiP)=0.01mg. in 200mL=0.26mg, in 40g extract =0.0064mg. So in mg/kg=36mg/kg. is this correct? Thank you guys.

[McCoy]

okay no one!

[Borek]

got approx 0.01mg . Is that correct?

Very approx.

My calculation: ascorbic acid is 482.4mg/L of orange juice.Anyone happy with that?

I am not. Show how you get this number.