Extraction of Soluble Fiber from Distillers' Grains

Abstract

The feasibility of using coproducts from dry grind corn ethanol production as a substrate for the production of soluble fiber was examined. Acid- and base-catalyzed hydrolysis experiments were performed using sulfuric acid and sodium hydroxide to partially hydrolyze hemicellulose content of whole stillage, a precursor to distillers' grains, to soluble fiber. The influences of temperature, reaction time, and hydrolyzing agent concentration on the formation of soluble fiber were studied. Soluble fiber was recovered by precipitation in a 95% ethanol solution. Results indicate that appreciable quantities of soluble fiber may be extracted using either acid- or base-catalyzed reactions. The highest yield of soluble fibers was 13.2 g per 100 g-db of treated whole stillage using one weight percent sodium hydroxide at 80ºC for 1 h. HPLC analysis was used to quantify the amount of monomeric sugars which were formed during the hydrolysis procedures.

Treating Distillers’ Grain from the Luzhou Aroma/Flavor Industry To Degrade Fiber

“…Moreover, the content of cellulose and hemicellulose after 2% NaOH pretreatment was only about 27.6% (Table ). This inconsistency could be attributed to the degradation of monomeric sugars, leading to production of lactic acid, formic acid, glycolic acid, acetic acid, cyclic enols, and phenolic compounds under high temperature in the presence of NaOH …”

“…During the distillation of the DG, a partial hemicellulose degradation process would occur. On the other hand, during the acid and alkali pretreatments, part of the hemicellulose was hydrolyzed to degradation products . We know that hemicellulose is a protective layer embedding cellulose to prevent enzyme attacking.…”

“…This inconsistency could be attributed to the degradation of monomeric sugars, leading to production of lactic acid, formic acid, glycolic acid, acetic acid, cyclic enols, and phenolic compounds under high temperature in the presence of NaOH. 32 3.3. Calcium Hydroxide Pretreatment.…”

“…On the other hand, during the acid and alkali pretreatments, part of the hemicellulose was hydrolyzed to degradation products. 32 We know that hemicellulose is a protective layer embedding cellulose to prevent enzyme attacking. Thus, the acid and alkaline pretreatments, resulting in partial hemicellulose degradation in this study, afford access for cellulase to directly react with cellulose fiber, while avoiding an additional enzymatic hydrolysis process for removal of hemicellulose.…”

Process options for the recovery of a pentosan-enriched fraction from wheat-based bioethanol thin stillage

“…Another potential option for the production of pentosans is their recovery from stillage, the main by-product of bioethanol production processes (Fig. 1 ) (Alyassin 2019 ; Chatzifragkou et al 2015 ; Flodman et al 2012 ; Kosik et al 2017 ). In the case of cereal-based ethanol production, such processing typically includes milling and saccharification of the raw cereal followed by alcoholic fermentation.…”