Efficacy of Antimicrobials Extracted from Organic Pecan Shell for Inhibiting the Growth of Listeria spp.

Abstract

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.

Bioactive components and health effects of pecan nuts and their by-products: a review

“…These authors also observed that LS extracts obtained with acetic acid showed higher inhibition than those obtained with methanol, while no inhibition was observed when water or hexane were used as extraction solvents. Babu et al (2013) obtained nutshell LS extract using a vacuum extraction process. Roasted LS showed lower MIC against Listeria monocytogenes than nonroasted LS.…”

Characterization of pecan shells and their effect on the physical properties and acceptability of smoked chicken breast

“…Babu et al. (2013) demonstrated that extracts of pecan shell could inhibit Listeria spp. and L. monocytogenes serotypes when applied to a poultry skin model.…”

“…There have been a few studies examining other commercial uses for pecan shells, as for the production of biofuels (Dewi, Hudha, Rauda, & Tsulusia, 2019; Mohammad‐Khah & Ansari, 2009). Babu, Crandall, Johnson, O'Bryan, and Ricke (2013) demonstrated that natural pecan shell extract is a potent alternative antimicrobial against food pathogens, such as Listeria monocytogenes and other Listeria spp. Erickson (2018) researched conditions for extracting shell pigments that could provide caramel‐like color to foods.…”

Listeria Occurrence and Potential Control Strategies in Alternative and Conventional Poultry Processing and Retail

“…Other natural antimicrobials have been investigated for their use against Listeria spp. such as liquid smoke (Babu et al, 2013;Lingbeck et al, 2014). Liquid smoke is produced by condensing smoke created by burning flammable materials and subsequently removing carcinogenic polycyclic aromatic hydrocarbons (Lingbeck et al, 2014).…”

“…Liquid smoke is produced by condensing smoke created by burning flammable materials and subsequently removing carcinogenic polycyclic aromatic hydrocarbons (Lingbeck et al, 2014). Extract of organic pecan shells was tested on seven Listeria strains by Babu et al (2013). A proprietary solvent-free extract system was applied and volatile gaseous were condensed into liquid smoke.…”