title: Effect of Grapefruit Seed Extract on Thermal Inactivation of Listeria monocytogenes during Sous-Vide Processing of Two Marinated Mexican Meat Entrées.
abstract: D- and z-values for Listeria monocytogenes were obtained for two Mexican meat entrées: pork meat marinated in tomatillo (green tomato) sauce (PTS) and beef marinated in a red chili sauce (BRCS), with addition of 0, 200, and 800 ppm of grapefruit seed extract (GSE). Meat samples inoculated with L. monocytogenes were packaged in sterile bags, immersed in a water bath, and held at 55, 57.5, 60, and 62.5°C for different periods of time. Depending upon the temperature, D-values at 0 ppm of GSE ranged from 26.19 to 2.03 min in BRCS and 26.41 to 0.8 min in PTS. Adding 800 ppm of GSE to BRCS thermally treated at 55 and 62.5°C significantly decreased inactivation time by 35%. A reduction in time of 25.9, 10.6, and 40.1% at 55, 57.5, and 60°C, respectively, was observed in PTS with 800 ppm of GSE. The z-values of L. monocytogenes were not significantly affected by GSE addition; average z-values were 7.25 and 5.09°C for BRCS and PTS, respectively. Estimated thermal lethality for a 7-D log reduction of L. monocytogenes under commercial-size sous-vide conditions at a reference temperature of 55°C was reached at 78 and 71 min for BRCS without and with 800 ppm of GSE, respectively. For PTS, 7-D reduction was attained at 69 and 61 min without and with addition of 800 ppm of GSE, respectively. Supplementing both Mexican meat entrées (BRCS and PTS) with 800 ppm of GSE rendered L. monocytogenes cells more sensitive to the lethal effect of heat. The results of this study will assist the retail food industry in designing acceptance limits on critical control points pertaining to cooking regimes to effectively eliminate L. monocytogenes in BRCS and PTS sous-vide processed Mexican meat entrées.
authors.affiliation: Centro de Investigación en Alimentación y Desarrollo, A.C., Laboratorio de Ciencia y Tecnología de la Carne, Carretera a la Victoria, Hermosillo, Sonora, México CP 83304, USA.
authors.forename: Martin
authors.initials: M
authors.lastname: Valenzuela-Melendres
authors.affiliation: Centro de Investigación en Alimentación y Desarrollo, A.C., Laboratorio de Ciencia y Tecnología de la Carne, Carretera a la Victoria, Hermosillo, Sonora, México CP 83304, USA. aida@ciad.mx.
authors.forename: E Aida
authors.initials: EA
authors.lastname: Peña-Ramos
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Eastern Regional Research Center, 600 East Mermaid Lane, Wyndmoor, Pennsylvania 19308, USA.
authors.forename: Vijay K
authors.initials: VK
authors.lastname: Juneja
authors.affiliation: Centro de Investigación en Alimentación y Desarrollo, A.C., Laboratorio de Ciencia y Tecnología de la Carne, Carretera a la Victoria, Hermosillo, Sonora, México CP 83304, USA.
authors.forename: Juan Pedro
authors.initials: JP
authors.lastname: Camou
authors.affiliation: Centro de Investigación en Alimentación y Desarrollo, A.C., Laboratorio de Ciencia y Tecnología de la Carne, Carretera a la Victoria, Hermosillo, Sonora, México CP 83304, USA.
authors.forename: German
authors.initials: G
authors.lastname: Cumplido-Barbeitia
mesh_terms: D000818:Animals; D032083:Citrus paradisi; D015169:Colony Count, Microbial; D005511:Food Handling; D005516:Food Microbiology; D006358:Hot Temperature; D008089:Listeria monocytogenes; D008460:Meat; D008461:Meat Products; D008800:Mexico; D000069466:Red Meat; D012639:Seeds; D013552:Swine; D013997:Time Factors