To estimate the total sugars in the molasses (both reducing and non reducing) go for the most popular phenol- sulphuric acid method (known as Dubios method) and for reducing sugars you can rely on DNS method developed by Miller et al.

Accurate method to identify all sugar in molasses would be HPLC but you have to dilute a lot and filter properly. For chemical method DNS in popular but i have not found it working with molasses. The molasses colour interfere a bit in final reading and also the initial conc of total sugar is quite high 55% to 45% in molasses (depending on type of analysis) while DNS method detects sugar in PPM. So you have to dilute the molasses a lot and then the reaction colour interfers with the standard which we use stock glucose.

  I have personally worked with molasses for 2 years and along with HPLC, i have used Lane and Eynon method (felling method) to determine total sugar conc. at different stage. Its not as accurate method as DNS though but it give good, reproducible results

This is the link of reference, though i used a modified method develop in our lab. If you need it, i can msg you.

Lane and Eynon, J. Soc. Chem. Ind. 42, 32, 1923.

Best of Luck

Hello,

DNS is commum one for rapid tests, but there's no publication using it due to the errors it can happen in this test with molasses. You will not find good results neither repetitive ones. I worked with this last year and I know the dificulties. Just to add, with every food matrix with dark colors were like that (coffee, molasses, sugarcane juice etc).

All of this information were already studied and also measured. I have the reference work of it, if you want.

So, I suggest you to apply Lane Eynnon method. This is the most secure and accurate for want you desire.

Good Luck!

Thanks Anna, Can you pleas send the reference?

Hello Abdelrahman,

You're welcome. They are here, like links, because I tried to do it as attachment of files and they were not attached. The unique thing is that  they are written in portuguese, so you have to translate it.

Hope that you have a good lucky in your research.

http://www.scielo.br/scielo.php?pid=S0100-204X2002000500020&script=sci_arttext

http://www.orplana.com.br/manual_2006.pdf

So Kind of you Anna, Thanks a lot :)

You're welcome, Abdelrahman!

Hello everyone

i want to calculate total sugar in bran autohydrolysate by using DNS method and so i determined reducing sugar befor and after acid hydrolysis. now how can i calculate and  report total sugar? thanks for any reply