SmartTest
Family
Hand held MS2123 Moisture Series
Water Activity Analyzer
Ref: HMS2123sWAIntE
Version: 2002-02-26
Recommended Measurement for Micro-biological, Chemical, Ultra fine powder and Enzymatic Materials
Typical Applications:
Food, pharmaceutical, coatings, hygroscopic powders, pills, paper, photographic film industry
Why Use Water Activity Terminology?
The active part of
moisture content and, therefore, water activity, provide better information
than the total moisture content regarding the micro-biological, chemical and
enzymatic stability of perishable products such as foods and seeds. For similar
reasons, water activity is equally relevant in the pharmaceutical industry
where it provides useful information regarding the cohesion of tablets and
pills, or the adherence of coatings. Water activity can be directly compared
with the relative humidity of the ambient air to prevent dimensional changes in
a product (paper, photographic film), to prevent hygroscopic powders (powdered
sugar, salt) from caking or turning into a solid block, etc.
Water activity can be used with some products (mostly synthetic products) as a
means of indirectly measuring the total moisture content. This requires
developing sorption isotherms to this purpose. Sorption isotherms are graphs
that provide the relationship between water activity and moisture content at
constant temperature. For most natural products, repeatable sorption isotherms
cannot be reliably developed and water activity should be regarded as separate
from moisture content.
Series
accessories, test gas, liquids to solids with the one instruments
Water Activity Definition
Water activity Aw
(or equilibrium relative humidity %ERH) measures the vapor pressure generated
by the moisture present in a hygroscopic product.
Aw = p / ps and %ERH = 100 x Aw, where:
p :
partial pressure of water vapor at the surface of the product
ps : saturation pressure, or the partial pressure of water vapor above
pure water at the product temperature
Water activity reflects the active part of moisture content or the part which,
under normal circumstances, can be exchanged between the product and its
environment.
Water activity is usually defined under static conditions of equilibrium. Under
such conditions, the partial pressure of water vapor (p) at the surface of the
product is equal to the partial pressure of water vapor in the immediate
environment of the product. Any exchange of moisture between the product and
its environment is driven by a difference between these two partial pressures.
Accelerated water
activity measurement in typically 5 minutes
Conventional water
activity measurement with automatic detection of equilibrium
Includes carrying
case, sample holder, disposable sample cups, humidity calibration standards.
Optional docking
station with external AC adapter for bench top use
HBD5ms2100 analyzer accepts a large choice of probes, suitable for the direct measurement of products in bulk and other applications.
Instrument Functions
l Water activity test
l Moulds Free Safe Days (MFSL) prediction
l Humidity, temperature test
l Moisture measurement for gas, liquids and solids
l pH test supported
l Conductance test supported
Specifications
Aw Range: 0.03-1.000
Accuracy: 0.015Aw (<+/-0.3°C, at room temperature )
Repeatability:< 0.005 Aw (<0.1°C, at room temperature)
Temperature: -20 to 85°C; -50 to 200°C
Instrument environ: -10 to 60°C； 0-99%RH
Battery supply
3 mode to test:
Test time: ~5 min Typical at WASmart:
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