Campus Units

Civil, Construction and Environmental Engineering, Agricultural and Biosystems Engineering, Food Science and Human Nutrition, Biorenewable Resources and Technology

Document Type

Article

Publication Version

Published Version

Publication Date

2015

Journal or Book Title

Journal of Agricultural and Food Chemistry

Volume

63

Issue

21

First Page

5239

Last Page

5248

DOI

10.1021/acs.jafc.5b00563

Abstract

Ozonation of uncooked corn mash from the POET BPX process was investigated as a potential disinfection method for reducing bacterial contamination prior to ethanol fermentation. Corn mash (200 g) was prepared from POET ground corn and POET corn slurry and was ozonated in 250 mL polypropylene bottles. Lactic and acetic acid levels were monitored daily during the fermentation of ozonated, aerated, and nontreated corn mash samples to evaluate bacterial activity. Glycerol and ethanol contents of fermentation samples were checked daily to assess yeast activity. No yeast supplementation, no addition of other antimicrobial agents (such as antibiotics), and spiking with a common lactic acid bacterium found in corn ethanol plants,Lactobacillus plantarum, amplified the treatment effects. The laboratory-scale ozone dosages ranged from 26–188 mg/L, with very low estimated costs of $0.0008–0.006/gal ($0.21–1.6/m3) of ethanol. Ozonation was found to decrease the initial pH of ground corn mash samples, which could reduce the sulfuric acid required to adjust the pH prior to ethanol fermentation. Lactic and acetic acid levels tended to be lower for samples subjected to increasing ozone dosages, indicating less bacterial activity. The lower ozone dosages in the range applied achieved higher ethanol yields. Preliminary experiments on ozonating POET corn slurry at low ozone dosages were not as effective as using POET ground corn, possibly because corn slurry samples contained recycled antimicrobials from the backset. The data suggest additional dissolved and suspended organic materials from the backset consumed the ozone or shielded the bacteria.

Comments

Reprinted with permission from J. Agric. Food Chem., 2015, 63 (21), pp 5239–5248. doi: 10.1021/acs.jafc.5b00563. Copyright 2015 American Chemical Society.

Copyright Owner

American Chemical Society

Language

en

File Format

application/pdf

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