Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices
A wide range of drying parameters and methods are used by industry to produce dried apples. To ensure end-product safety and regulatory compliance, it is essential to evaluate the effectiveness of such industrial practices on microbial inactivation. Therefore, the objective of this study was to eval...
| Main Authors: | , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2024-04-01
|
| Series: | Journal of Food Protection |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S0362028X24000371 |
| _version_ | 1797209693214474240 |
|---|---|
| author | Narindra Randriamiarintsoa Elliot T. Ryser Bradley P. Marks |
| author_facet | Narindra Randriamiarintsoa Elliot T. Ryser Bradley P. Marks |
| author_sort | Narindra Randriamiarintsoa |
| collection | DOAJ |
| description | A wide range of drying parameters and methods are used by industry to produce dried apples. To ensure end-product safety and regulatory compliance, it is essential to evaluate the effectiveness of such industrial practices on microbial inactivation. Therefore, the objective of this study was to evaluate the effects of drying air temperature and velocity on Listeria monocytogenes inactivation during drying of apple slices. Apples (cv. Gala) were cored, sliced as rings (∼6 mm thick), and surface-inoculated with broth-grown culture of an 8-strain cocktail of L. monocytogenes to achieve an inoculation level of 8.6 ± 0.3 log CFU/g. Apple rings were dried in batches using dry air in a pilot-scale impingement oven at 60 or 80 °C air temperature and 0.7 or 2.1 m/s air velocity, and sampled every 30 min for bacterial enumeration, water activity (aw), and moisture content analysis. L. monocytogenes reduction increased (P < 0.05) with higher air velocity or higher drying air temperature. By the end of drying, in which the standard moisture content for dried apple slices of <24% wet basis was reached, L. monocytogenes was reduced by 1.8 ± 0.3 and 2.8 ± 0.7 log CFU/g at 0.7 and 2.1 m/s air velocity, respectively, after 180 min at 60 °C. When using 80 °C drying temperature, L. monocytogenes reduction was 5.2 ± 0.5 log CFU/g at both air velocities after 150 min. Therefore, process conditions should be considered in the validation of fruit drying processes, instead of solely relying on product endpoint properties, such as moisture content. |
| first_indexed | 2024-03-07T14:30:07Z |
| format | Article |
| id | doaj.art-73ae237cd4674ede9f2f059eadc6dfe2 |
| institution | Directory Open Access Journal |
| issn | 0362-028X |
| language | English |
| last_indexed | 2024-04-24T09:58:45Z |
| publishDate | 2024-04-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Journal of Food Protection |
| spelling | doaj.art-73ae237cd4674ede9f2f059eadc6dfe22024-04-14T04:10:03ZengElsevierJournal of Food Protection0362-028X2024-04-01874100253Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple SlicesNarindra Randriamiarintsoa0Elliot T. Ryser1Bradley P. Marks2Department of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI 48824, USADepartment of Food Science and Human Nutrition, Michigan State University, East Lansing, MI 48824, USADepartment of Biosystems and Agricultural Engineering, Michigan State University, East Lansing, MI 48824, USA; Corresponding author. Address: 524 S. Shaw Ln; East Lansing, MI 48824, USA.A wide range of drying parameters and methods are used by industry to produce dried apples. To ensure end-product safety and regulatory compliance, it is essential to evaluate the effectiveness of such industrial practices on microbial inactivation. Therefore, the objective of this study was to evaluate the effects of drying air temperature and velocity on Listeria monocytogenes inactivation during drying of apple slices. Apples (cv. Gala) were cored, sliced as rings (∼6 mm thick), and surface-inoculated with broth-grown culture of an 8-strain cocktail of L. monocytogenes to achieve an inoculation level of 8.6 ± 0.3 log CFU/g. Apple rings were dried in batches using dry air in a pilot-scale impingement oven at 60 or 80 °C air temperature and 0.7 or 2.1 m/s air velocity, and sampled every 30 min for bacterial enumeration, water activity (aw), and moisture content analysis. L. monocytogenes reduction increased (P < 0.05) with higher air velocity or higher drying air temperature. By the end of drying, in which the standard moisture content for dried apple slices of <24% wet basis was reached, L. monocytogenes was reduced by 1.8 ± 0.3 and 2.8 ± 0.7 log CFU/g at 0.7 and 2.1 m/s air velocity, respectively, after 180 min at 60 °C. When using 80 °C drying temperature, L. monocytogenes reduction was 5.2 ± 0.5 log CFU/g at both air velocities after 150 min. Therefore, process conditions should be considered in the validation of fruit drying processes, instead of solely relying on product endpoint properties, such as moisture content.http://www.sciencedirect.com/science/article/pii/S0362028X24000371Air flowDehydrationFruitMoisturePathogenThermal inactivation |
| spellingShingle | Narindra Randriamiarintsoa Elliot T. Ryser Bradley P. Marks Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices Journal of Food Protection Air flow Dehydration Fruit Moisture Pathogen Thermal inactivation |
| title | Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices |
| title_full | Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices |
| title_fullStr | Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices |
| title_full_unstemmed | Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices |
| title_short | Effect of Air Temperature and Velocity on Listeria monocytogenes Inactivation During Drying of Apple Slices |
| title_sort | effect of air temperature and velocity on listeria monocytogenes inactivation during drying of apple slices |
| topic | Air flow Dehydration Fruit Moisture Pathogen Thermal inactivation |
| url | http://www.sciencedirect.com/science/article/pii/S0362028X24000371 |
| work_keys_str_mv | AT narindrarandriamiarintsoa effectofairtemperatureandvelocityonlisteriamonocytogenesinactivationduringdryingofappleslices AT elliottryser effectofairtemperatureandvelocityonlisteriamonocytogenesinactivationduringdryingofappleslices AT bradleypmarks effectofairtemperatureandvelocityonlisteriamonocytogenesinactivationduringdryingofappleslices |