Growers and processors of USDA certified organic foods are in need of suitable organic antimicrobials. The purpose of the research reported here was to develop and test natural antimicrobials derived from an all-natural by-product, organic pecan shells. Unroasted and roasted organic pecan shells were subjected to solvent free extraction to produce antimicrobials that were tested against Listeria spp. and L. monocytogenes serotypes to determine the minimum inhibitory concentrations (MIC) of antimicrobials. The effectiveness of pecan shell extracts were further tested using a poultry skin model system and the growth inhibition of the Listeria cells adhered onto the skin model were quantified. The solvent free extracts of pecan shells inhibited Listeria strains at MICs as low as 0.38%. The antimicrobial effectiveness tests on a poultry skin model exhibited nearly a 2 log reduction of the inoculated cocktail mix of Listeria strains when extracts of pecan shell powder were used. The extracts also produced greater than a 4 log reduction of the indigenous spoilage bacteria on the chicken skin. Thus, the pecan shell extracts may prove to be very effective alternative antimicrobials against food pathogens and supplement the demand for effective natural antimicrobials for use in organic meat processing.

Perennial forage grasses have potential as cellulosic feedstocks. Outside storage as round bales is a likely mode of storage; however, little is known of storage effects. The objective of this study was to determine the effects of baled storage method on saccharification, namely the recovery of glucose and xylose, and production of inhibitors after dilute acid pretreatment and enzymatic hydrolysis. Mature switchgrass (Panicum virgatum L. cv. Alamo) was harvested in Fayetteville, AR and packaged in large round bales in October 2010. There were two baling times: one soon after cutting when there was no rainfall and the other after a rainfall event. The bales that did not receive rain were stored either in an open barn or unprotected in the field. Bales made from rained‐on switchgrass were only stored unprotected in the field. Samples were taken from the windrows right before baling, and after a maximum 65‐day storage period. Field storage increased lignin content in biomass relative to barn storage, but carbohydrate constituents were not affected. Field storage decreased production of hydroxymethylfurfural and increased production of furfural relative to barn storage. Results indicate that protected storage conditions for switchgrass biomass in round bales can lead to greater preservation of fermentable sugars and reduced production of the important inhibitor furfural.