Application of rotary microfiltration in debittering process of spent brewer's yeast [An article from: Bioresource Technology]
Book Details
PublisherElsevier
ISBN / ASINB000RR5TAC
ISBN-13978B000RR5TA7
AvailabilityAvailable for download now
Sales Rank12,846,373
MarketplaceUnited States 🇺🇸
Description
This digital document is a journal article from Bioresource Technology, published by Elsevier in . The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description:
This study concerns the production of yeast extract from spent brewer's yeast using rotary microfiltration as a means to combine debittering and cell debris separation into a single step, without using a toxic alkali wash. The pH of yeast homogenate was found to affect protein yield and bitterness of the product. Rotary filtration of yeast homogenate at various pHs resulted in different percent protein transmissions. These were found to be 5.05%, 9.83%, and 30.83% for pH 5, 6, and 7.5, respectively. The bitterness concentration in the permeate was also found to be higher at higher pHs. Autolysis of the cell homogenate prior to filtration increased protein yield and decreased bitterness considerably. At pH 5.5, the protein transmission was increased to 60% and debittering efficiency was increased from 59% to 86%. The permeate flux and protein productivity could be further increased by increasing the rotational speed, but this resulted in a decrease in debittering efficiency. Thus, the rotational speed should be carefully selected to compromise between the yield and product quality. Furthermore, for the tested rotational speeds of 600 and 1000rpm, the change in feed flow rate from 11 to 35Lh^-^1 changes the flow behavior from turbulent vortex flow to laminar vortex flow, thus decreasing the flux and protein productivity.
Description:
This study concerns the production of yeast extract from spent brewer's yeast using rotary microfiltration as a means to combine debittering and cell debris separation into a single step, without using a toxic alkali wash. The pH of yeast homogenate was found to affect protein yield and bitterness of the product. Rotary filtration of yeast homogenate at various pHs resulted in different percent protein transmissions. These were found to be 5.05%, 9.83%, and 30.83% for pH 5, 6, and 7.5, respectively. The bitterness concentration in the permeate was also found to be higher at higher pHs. Autolysis of the cell homogenate prior to filtration increased protein yield and decreased bitterness considerably. At pH 5.5, the protein transmission was increased to 60% and debittering efficiency was increased from 59% to 86%. The permeate flux and protein productivity could be further increased by increasing the rotational speed, but this resulted in a decrease in debittering efficiency. Thus, the rotational speed should be carefully selected to compromise between the yield and product quality. Furthermore, for the tested rotational speeds of 600 and 1000rpm, the change in feed flow rate from 11 to 35Lh^-^1 changes the flow behavior from turbulent vortex flow to laminar vortex flow, thus decreasing the flux and protein productivity.
