Effects of storage and formulating conditions of dairy products on physiology of adjunct and spoiler molds
In dairy industry, some filamentous fungi are used as adjuncts whereas others are responsible for dairy product spoilage. Their development could be controlled by several abiotic factors. The aim of this work was to study the effect of water activity and modified atmospheres on conidial germination...
| Main Author: | |
|---|---|
| Other Authors: | , , , |
| Format: | Doctoral or Postdoctoral Thesis |
| Language: | French |
| Published: |
HAL CCSD
2022
|
| Subjects: | |
| Online Access: | https://theses.hal.science/tel-04088666 https://theses.hal.science/tel-04088666/document https://theses.hal.science/tel-04088666/file/These-2022-EGAAL-Microbiologie_virologie_et_parasitologie-VALLE_Marion.pdf |
| Summary: | In dairy industry, some filamentous fungi are used as adjuncts whereas others are responsible for dairy product spoilage. Their development could be controlled by several abiotic factors. The aim of this work was to study the effect of water activity and modified atmospheres on conidial germination of Penicillium camemberti and radial growth of sixteen different molds encountered in dairy environment. Water availability decrease as well as ionic strength increase delayed conidial germination and radial growth. A CO2 partial pressure of 70% did not inhibit neither the conidial germination nor the radial growth of all the tested strains. The majority of strains were sensitive to CO2 partial pressure while some strains were sensitive to undissociated carbonic acid. Several models currently used for bacteria were adapted to describe the mold responses and thus improve the predictive mycology tools. A study was performed on soft mold ripened cheeses with color defects. The results showed that a heterogenous salting seems to inhibit the development of micro-organisms used to cover cheese surfaces and thus at the origin of production defect. Dans l’industrie laitière, certains champignons filamenteux sont utilisés comme ferments alors que d’autres sont responsables de l’altération des produits laitiers. Leur développement peut être contrôlé par plusieurs facteurs abiotiques. L’objectif de ce travail est d’étudier l’effet de l’activité de l’eau et des atmosphères modifiées sur la germination des spores de Penicillium camemberti et la croissance radiale de seize moisissures rencontrées dans l’environnement laitier. Une diminution de la disponibilité en eau et une augmentation de la force ionique retardent la germination des spores et la croissance radiale. Une pression partielle en CO2 de 70% ne permet pas d’inhiber la germination des spores et la croissance radiale de toutes les souches étudiées. La majorité des souches sont sensibles à la pression partielle en CO2 tandis que certaines sont sensibles à l’acide ... |
|---|