title: Influence of moisture content on microbial activity and silage quality during ensilage of food processing residues.
abstract: Seasonally produced biomass such as sugar beet pulp (SBP) and tomato pomace (TP) needs to be stored properly to meet the demand of sustainable biofuel production industries. Ensilage was used to preserve the feedstock. The effect of moisture content (MC) on the performance of ensilage and the relationship between microorganism activities and MC were investigated. For SBP, MC levels investigated were 80, 55, 30, and 10% on a wet basis. For TP, MC levels investigated were 60, 45, 30, and 10%. Organic acids, ethanol, ammonia, pH and water soluble carbohydrates (WSC) were measured to evaluate the silage quality. Ensilage improved as the MC decreased from 80 to 55% for SBP and from 60 to 45% for TP. When the MC decreased to 30%, a little microbial activity was detected for both feedstocks. Storage at 10% MC prevented all the microbial activity. The naturally occurring microorganisms in TP were found to preserve TP during silage and were isolated and determined by polymerase chain reaction (PCR). The results suggest that partial drying followed by ensilage may be a good approach for stabilization of food processing residues for biofuels production.
authors.affiliation: Biological and Agricultural Engineering Department, University of California, Davis, Bainer Hall, One Shields Avenue, Davis, CA 95616, USA. yizheng@ucdavis.edu
authors.forename: Yi
authors.initials: Y
authors.lastname: Zheng
authors.forename: Matthew
authors.initials: M
authors.lastname: Yates
authors.forename: Hnin
authors.initials: H
authors.lastname: Aung
authors.forename: Yu-Shen
authors.initials: YS
authors.lastname: Cheng
authors.forename: Chaowei
authors.initials: C
authors.lastname: Yu
authors.forename: Hongyun
authors.initials: H
authors.lastname: Guo
authors.forename: Ruihong
authors.initials: R
authors.lastname: Zhang
authors.forename: Jean
authors.initials: J
authors.lastname: Vandergheynst
authors.forename: Bryan M
authors.initials: BM
authors.lastname: Jenkins
mesh_terms: D000641:Ammonia / Q000378:metabolism; D027461:Beta vulgaris / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D056804:Biofuels; D018533:Biomass; D002241:Carbohydrates / Q000032:analysis / Q000096:biosynthesis; D000431:Ethanol / Q000378:metabolism; D005511:Food Handling / Q000379:methods*; D005516:Food Microbiology; D006863:Hydrogen-Ion Concentration; D018551:Solanum lycopersicum / Q000737:chemistry / Q000378:metabolism / Q000382:microbiology*; D050296:Microbial Viability; D009930:Organic Chemicals / Q000378:metabolism; D028321:Plant Preparations; D012820:Silage / Q000032:analysis*; D014867:Water / Q000032:analysis* / Q000737:chemistry
chemical_list: D056804:Biofuels; D002241:Carbohydrates; D009930:Organic Chemicals; D028321:Plant Preparations; D014867:Water; D000431:Ethanol; D000641:Ammonia