Analysis Package P13 : Sugars and Oligosaccharides in Solution

This package is particularly suitable for analysing the liquid output streams from biomass pre-treatment, hydrolysis, and other conversion processes. It can be used to determine the total oligomeric sugar content of a liquid and also the relative proportions that each monosaccharide contributes to this total amount. The package involves a number of stages of analysis.

Firstly, the liquid is analysed using our ion chromatography system for the free monosaccharides and disaccharides in solution, just as in package P21 - Sugars in Solution.

Then we subject the liquid to a mild form of acid hydrolysis involving 4% sulphuric acid and 1 hour in an autoclave at 121 degrees Celcius. These conditions will break apart any oligosaccharides into their constituent monosaccharide units.

The liquid is subsequently filtered and analysed again on our IC system, to determine the amounts of various monosaccharides, after correction for any losses in sugars associated with the hydrolysis process. For each monosaccharide there will now be two values, the concentration prior to hydrolysis and that after hydrolysis.

With the exception of fructose (which degrades to hydroxymethylfurfural during the autoclaving step) all monosaccharides should be present in greater concentration post-hydrolysis. Hence, the proportion of each sugar that is present in the original liquid in the oligomeric form can be calculated by subtracting the pre-hydrolysis concentration from the post-hydrolysis concentration. As we report the sucrose and cellobiose contents separately we correct the calculated oligomeric glucan content using those data.

In our reports for this package we report the pre-hydrolysis, post-hydrolysis and oligomeric concentrations of each sugar.

If you are also interested in finding the amounts of various sugar-degradation products in your liquid then, in addition to this analysis package, we would also recommend analysis package P22 - Organic Acids and Furans which can quantify a number of products, including levulinic acid, furfural, and formic acid).

If you are considering this analysis package to evaluate the outcome of your pre-treatment process, we have outlined a recommended set of analysis packages that will allow you to get detailed information about process yields and efficiencies.