Comparison of the new vapor sorption analyzer to the traditional saturated salt slurry method and the dynamic vapor sorption instrument
type: CreativeWork
description: Water is a key component of food materials. One of the most useful aspects of the water activity (aw) concept is the moisture sorption isotherm, which plots the moisture content of a material as a function of aw at the same temperature. Moisture sorption isotherms are useful for a variety of processing and product stability applications. The most common methods of generating equilibrium moisture sorption isotherms are using saturated salt slurries (SSS) or humidity generating instruments. The saturated salt slurry method has been a standard method for many years, but there are several drawbacks to this method, including long equilibration times, extensive labor required, and mold growth at high aw values. Many of the disadvantages of the SSS method have been overcome by humidity generating instruments represented by the Dynamic Vapor Sorption (DVS) instrument from Surface Measurement Systems Ltd. There have been several studies done to show that the humidity generating instruments are reliable in terms of their accuracy compared to the SSS method. The Vapor Sorption Analyzer (VSA) is a new type of isotherm generating instrument. The VSA collects aw and weight change data similar to the DVS, but has the added benefit of being able to generate non-equilibrium isotherms as well. Currently, there are a few methods able to produce non-equilibrium isotherms, but no instrument has the capability of producing both types of isotherms. Within this one instrument, the uniqueness of each type of isotherm can be used in order to obtain the most information about the moisture characteristics of a material. Since the VSA still overcomes most of the drawbacks of the saturated salt slurry method and also has the capability of generating both types of isotherms, it would be beneficial to make use of this new instrument. However, no research has been published that investigates the accuracy of the VSA compared to the SSS method or other humidity generating instruments. This research i…
abstract: Water is a key component of food materials. One of the most useful aspects of the water activity (aw) concept is the moisture sorption isotherm, which plots the moisture content of a material as a function of aw at the same temperature. Moisture sorption isotherms are useful for a variety of processing and product stability applications. The most common methods of generating equilibrium moisture sorption isotherms are using saturated salt slurries (SSS) or humidity generating instruments. The saturated salt slurry method has been a standard method for many years, but there are several drawbacks to this method, including long equilibration times, extensive labor required, and mold growth at high aw values. Many of the disadvantages of the SSS method have been overcome by humidity generating instruments represented by the Dynamic Vapor Sorption (DVS) instrument from Surface Measurement Systems Ltd. There have been several studies done to show that the humidity generating instruments are reliable in terms of their accuracy compared to the SSS method. The Vapor Sorption Analyzer (VSA) is a new type of isotherm generating instrument. The VSA collects aw and weight change data similar to the DVS, but has the added benefit of being able to generate non-equilibrium isotherms as well. Currently, there are a few methods able to produce non-equilibrium isotherms, but no instrument has the capability of producing both types of isotherms. Within this one instrument, the uniqueness of each type of isotherm can be used in order to obtain the most information about the moisture characteristics of a material. Since the VSA still overcomes most of the drawbacks of the saturated salt slurry method and also has the capability of generating both types of isotherms, it would be beneficial to make use of this new instrument. However, no research has been published that investigates the accuracy of the VSA compared to the SSS method or other humidity generating instruments. This research i…
author: Penner, Elizabeth
language: en
keywords: water activity, moisture content, isotherm
date published: 2013-08-22T16:38:50Z
date modified: 2026-07-22T22:25:34Z
provider: University of Illinois - Urbana-Champaign
publisher: Networked Digital Library of Theses and Dissertations
type: WebPage
source organization: University of Illinois at Urbana-Champaign

PropertyValue
property ID: Handle
value: http://hdl.handle.net/2142/45392