CSC Scientific Blog

A blog about test equipment

CSC Scientific Blog

Moisture Content and Water Activity - What Are They?

Posted by Art Gatenby on May 30, 2013 1:23:00 PM

Many accessing our web site ask questions such as:

  • “How does water content affect water activity?”

  • "How is water activity different from water content?”

  • ”Can I convert from moisture to water activity?”

I previously commented on water activity and now hope to clarify the differences between water activity and moisture content. Given that both of these measurements deal with water connected to a material, we must first understand of water content in a product.

Read More

Topics: Moisture Sorption Isotherm, Moisture Analysis, Water Activity, moisture content, moisture measurement, water activity measurement, water content measurement

Moisture Content Analyzer News

Posted by Art Gatenby on Mar 5, 2013 3:47:00 PM

I am very excited about a new update to the CSC Digital Moisture Balance.  To give you a perspective of why I’m excited about this Moisture Content Analyzer update, I thought you my be interested in the story of the transition from a classic mechanical moisture analyzer to the current highly robust and durable electronic instrument of today. 

Read More

Topics: Moisture Analysis, Moisture Testing, Loss-On-Drying

Do I Need A Karl Fischer Oven?

Posted by Art Gatenby on Jan 23, 2013 6:20:00 PM

As you know the Karl Fischer Method of moisture analysis has a reputation of being water specific. The method works through the use of a special Karl Fischer Reagent.

Read More

Topics: Coulometric Karl Fischer, Volumetric Karl Fischer, Moisture Analysis, Karl Fischer Oven, Karl Fischer, Karl Fischer Titration

Coulometric Or Volumetric Karl Fischer -- Which Should I Use?

Posted by Art Gatenby on Jul 3, 2012 12:27:00 PM

As usual when we pose a question,like:

Should you use Coulometric or Volumetric Karl Fischer to measure moisture in your product?

We often get a the reaction, “So Who Cares?” We'll try to answer both questions.

Read More

Topics: Coulometric Karl Fischer, Volumetric Karl Fischer, Moisture Analysis, Moisture Testing, Karl Fischer, Karl Fischer Titration

What is Moisture Content?

Posted by Art Gatenby on May 29, 2012 3:24:00 PM

Last week, as I was reflecting on a recent moisture content problem, I recalled our series “Loss-on Drying and Other Moisture Mysteries.” In that series I examined moisture chemistry in products. However, I did little to define moisture content.

Read More

Topics: Bound Moisture, Free Moisture, Moisture Analysis, Water Activity, Moisture Testing, Karl Fischer, Karl Fischer Titration, Moisture

Moisture Content - Water Activity – Are They the Same Thing?

Posted by Art Gatenby on Mar 6, 2012 4:19:00 PM

The other day, I woke up with a lingering quandary: Are the concepts of

Moisture Content and Water Activity the same thing?

As usual, I’ve decided to take on the task of clarifying the difference.  I hope I pull it off.

From the perspective of someone who supplies instruments that measure moisture content, water activity has not been a primary consideration.  However, I believe that comparison and contrast of these important concepts will be useful.

Read More

Topics: Moisture Sorption Isotherm, Infrared Moisture, Moisture Analysis, Water Activity, Moisture Testing

Why Do I Get Inconsistent Moisture Test Results?

Posted by Art Gatenby on Oct 14, 2011 2:32:00 PM

Why are my Moisture Test results inconsistent?” 

That is an issue for many of you who test for moisture. We discussed the complexities and multiplicity of issues involved with moisture content determination in our “Loss-on Drying Moisture Analysis and other Moisture Mysteries” series.

In addition to intrinsic properties of test samples that may adversely affect moisture testing systems, automatic equipment parameter set-up, operator oversights and sample handling contribute to seemingly intractable moisture test result inaccuracies.

Read More

Topics: Moisture Analysis, Moisture Testing, Karl Fischer, Loss-On-Drying, Moisture

Karl Fischer Moisture – Answers to Questions We Get Asked

Posted by Art Gatenby on Jul 29, 2011 4:08:00 PM

When People are first introduced to the Karl Fischer Moisture Determination Method, eyes glaze over and we can perceive a mental “Why did I ask?

If you have any history with moisture analysis, you will have found, that for some applications, the Karl Fischer Titration Method is the best and sometimes the only way to get an accurate moisture measurement.

Read More

Topics: Moisture Analysis, Karl Fischer, Karl Fischer Titration, karl fischer moisture, karl fischer moisture determination, karl fischer questions

Loss-on Drying and Other Moisture Mysteries - Part V: Drying

Posted by Art Gatenby on Jun 15, 2011 12:55:00 PM

Just over six months ago, I began this journey explaining the simplest approach to measuring or determining moisture: Loss-on Drying. Little did I know how involved and esoteric it would become.

This voyage has taken me down mysterious paths through spooky theories, back to age-old chemistry concepts and into the vagaries of thermodynamics related to evaporation, vapor pressure, bound water and water activity. I have come full-circle; back to explaining Loss-on Drying -- a form of drying that I had assumed would be the simplest of all.

I thought the first four topics [evaporation, vapor pressure, bound moisture, water activity] were tough, complex, confounding and less-than-obvious. Drying -- defined as “the mass-transfer process of removing water (or other solute) by evaporation from a solid, semi solid or liquid” -- seemed easy.

As is often the case, reality makes “easy” a non-operative word. Such has turned out to be so with respect to the issue of drying.

Read More

Topics: Free Moisture, Moisture Sorption Isotherm, Moisture Analysis, Moisture Testing, Loss-On-Drying

Loss-On-Drying Moisture Analysis and Other Moisture Mysteries Part IV: Water Activity

Posted by Art Gatenby on Mar 31, 2011 3:39:00 PM

Loss-On-Drying moisture analysis seemed like a simple process until, in a state of naïve bliss, I promised to look at evaporation, vapor pressure and bound water. While I was otherwise occupied with these realities, I offered to enter the world of witchcraft and folklore; water activity.

Read More

Topics: Bound Moisture, Moisture Sorption Isotherm, Moisture Analysis, Water Activity, Loss-On-Drying

Subscribe via E-mail

Search the Blog

Posts by Topic