Combined d-Tryptophan Treatment and Temperature Stress Exert Antimicrobial Activity against Listeria monocytogenes in Milk
Autor: | Mohammed Elsherbini, Jian Chen, Shigenobu Koseki, Mahmoud Elafify, Adel Abdelkhalek, Maha Al-Ashmawy |
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Rok vydání: | 2020 |
Předmět: |
0106 biological sciences
Preservative Osmotic shock Gram-positive bacteria Colony Count Microbial medicine.disease_cause 01 natural sciences Microbiology 03 medical and health sciences Listeria monocytogenes medicine Animals Food science 0303 health sciences biology 030306 microbiology Chemistry Temperature Tryptophan biology.organism_classification Antimicrobial Temperature stress Heat stress Milk Food Microbiology Bacteria 010606 plant biology & botany Food Science |
Zdroj: | Journal of Food Protection. 83:644-650 |
ISSN: | 0362-028X |
DOI: | 10.4315/0362-028x.jfp-19-414 |
Popis: | d-Tryptophan (d-Trp) has a significant inhibitory effect on growth of gram-negative bacteria under osmotic stress. However, the inhibitory effect of d-Trp on the gram-positive Listeria monocytogenes under chilled and thermal stresses has not been evaluated previously. The effect of d-Trp on L. monocytogenes growth under cold and/or heat stress in milk and cream was dependent on the magnitude of the temperature stress. Low temperatures (4, 7, and 10°C) and treatment with 40 mM d-Trp resulted in significant inhibition of L. monocytogenes growth during the 4-week storage period. Lower temperatures more effectively inhibited growth. When added before thermal processing, 40 mM d-Trp completely inactivated L. monocytogenes (>6-log reduction) heated at 60°C for 25 min or 65°C for 20 min. These results suggest that d-Trp can be used as a preservative for controlling the growth of L. monocytogenes in milk and cream at refrigeration temperatures and could be used to enhance the thermal inactivation of L. monocytogenes. HIGHLIGHTS |
Databáze: | OpenAIRE |
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