acetone as described in patent mx 278768 however unlike the procedure described in that patent the first product has been already purified and contains 10 to 20 times more ferulated pentosans of high molecular weight than nejayote to precipitate these carbohydrates addition of at least double the volume of ethanol is recommended so working with a concentrated purified product represents savings from 10 to 20 times in the use of ethanol acetone and the costs related to recovery and purification of these solvents it is maintained that current 18 a has a purified product because it is a current that has already gone through a process of hydrolysis with amylases and it has been diafiltrated hence it is free of starch or carbohydrates of low molecular weight such as dextrins pentose oligomers or monomers of glucose xylose arabinose galactose ferulic acid and other molecules an additional advantage is that the ferulated pentosans present in current 18 a are much more homogeneous regarding their molecular weight than the ones obtained in the procedure described in patent mx 278768 since ultrafiltration allows them to be separated from the carbohydrates of a lower molecular weight than 100 kda of effective cut having a product more homogeneous in molecular weight is also directly correlated to the homogeneity of the physicochemical properties of the products to be developed or their respective application for example as a gelling agent it will be obvious to someone skilled in the art that membranes of lower effective cuts are also useful to retain this fraction of carbohydrates but the fluxes flow by membrane area unit are slower so a.