Graduate Thesis Or Dissertation

 

Impact of weak and strong acids on the destruction of lactic acid bacteria during high pressure processing Public Deposited

Downloadable Content

Download PDF
https://ir.library.oregonstate.edu/concern/graduate_thesis_or_dissertations/xk81jn24b

Descriptions

Attribute NameValues
Creator
Abstract
  • High hydrostatic pressure (HHP) affects the pH of weak acids due to an increased degree of acid dissociation while under pressure. The temporary pH reduction by high pressure in such a case may influence the barotolerance of microorganisms. The objective of this study was to determine the impact of weak and strong acids on the barotolerance of lactic acid bacteria across a range of pH under high hydrostatic pressure conditions. The effect of two acid groups (weak and strong) was studied on Lactobacillus plantarum (strain MDOS 32) at different pH levels (3.5 to 5). All high pressure treatments were carried for 1 minute over a range of pressures (350 – 525 MPa) at 25°C (at pressure). Population reductions were assessed by serial dilution followed by spiral plating, and pressure dependency of these reductions was modeled using the Weibull equation. Microbial inactivation was significantly affected by the type of acid (weak vs. strong), pH and pressure. In general, high pressure lethality of weak acids was greater compared to that of strong mineral acids. As the pH decreased from 5 to 3.5, high pressure lethality increased. The presence of whey protein isolate did not alter the lethality of the acid buffer systems.
License
Resource Type
Date Available
Date Issued
Degree Level
Degree Name
Degree Field
Degree Grantor
Commencement Year
Advisor
Committee Member
Academic Affiliation
Non-Academic Affiliation
Subject
Rights Statement
Publisher
Peer Reviewed
Language
File Format
File Extent
  • 350851 bytes
Replaces

Relationships

Parents:

This work has no parents.

In Collection:

Items