In the pharmaceutical industry, it’s not only about manufacturing to extraordinarily stringent standards of efficacy, it’s also about showing and proving you are meeting the high standards expected and also about delivering a product that looks, smells, feels, tastes and works exactly the same way each and every time.

Measurement, record keeping and proof are the key criteria against which any pharmaceutical QC/QA manager will be judged. 

The old adage of “It didn’t happen if it’s not written down” counts double in this demanding industry, and just as importantly – you can’t control what you don’t measure.  


Should I use Moisture Content or Water Activity for quality control?

Primarily, you must prove the quality of any product to the standards mandated for you.  With that said, the two considerations of moisture content or water activity are not always complementary when answering a question such as “which method is better”.  The goals that a well-informed QC manager/auditor needs to meet

·       Am I achieving the best possible quality, consistency, and profitability for my product? 

·       Am I meeting all regulatory and safety standards and can I demonstrate this?

For the contract manufacturer there is also a third goal that is independent of the other two 

·       Am I meeting the quality standards/CCPs that are set-out in the manufacturing agreement? 

With more than 35 ways of determining moisture content outlined in AOAC methods, the use of moisture content as a quality control metric is quickly being replaced by the use of water activity most applications. 

Not only does water activity provide a better prediction of product safety, there is also a primary test method (Dew Point Mirror) that provides a far greater level of repeatability and standardisation across different staff and locations than moisture content can. 

Moisture content has not been completely replaced however – some production procedures and regulatory clients still request this as a QC metric.  To meet these requirements, Meter Food have created the Aqualab AQ3, which can give BOTH moisture content AND water activity with a single test that delivers results in only 60 seconds.  

For the nutraceutical/supplement/pharmaceutical manufacturer the Aqualab AQ3 has the added advantage of offering full compliance with 21CFR Part 11 requirements.  


How do I prevent “crystals” forming in my powders?

In simple terms, crystals, lumps and clumps will form in a powder when there is too much moisture present.  This leads to a poor customer experience and can cause both dissatisfactions, and, just as importantly, the degradation of active ingredients. 

Do supplement powders need to be gas flushed/packed in a modified atmosphere?

The primary reason for gas flushing any product is to extend the shelf-life and/or provide a “better” customer experience.  This can mean Modifying the Atmosphere of the Package (i.e MAP) by replacing oxygen with an inert gas (normally nitrogen) or carbon dioxide to slow down/prevent oxygen driven reactions and degradation or replacing atmospheric air that is high in humidity with a very dry modified atmosphere to prevent increases in the water activity of a powder. 

Mätt Solutions offer a specialised consultancy service call “MAP Lab” that can help to determine: 

·       Will a specific product benefit from gas flushing/being packed in a modified atmosphere?

·       What gas mix is appropriate (or best) to meet specific goals?

·       How much will gas flushing extend the shelf-life of a specific product? 


My customers are complaining about lumps/crystals in my powders – why?

This is a very common problem with multi-component powders where the different components have different water activities. Most of us will remember from our high school chemistry classes that water will always move from an area of high concentration to an area of low concentration. Meter Group, who are specialists in tools for monitoring and measuring water activity have a very good explanation of this process on their website titled “Predict Moisture Migration with Water Activity” 

For further advice on how a powder may change on the shelf, and help in solving challenges with crystals, lumps or clumps, Matt Solutions can generate a Moisture Sorption Isotherm which can be an invaluable quality control tool and provide information to establish production CCP targets. 

I am experiencing excipient lumps and stickiness in some capsules but not others – why?

This is because the water activity and the moisture sorption isotherms of the different active ingredients are different.  Water activity will always try to equilibrate across the different components in a capsule – meaning that moisture may move from the excipient to the active ingredient or vice versa.  If this movement of moisture takes either component beyond a “phase transition” point, lumps, crystals and stickiness may be experienced. 

The way to avoid these problems is by engineering the different components (powders) that make up the contents of a powder, sachet or gel-cap to be at the same water activity with the use of humectants.  To understand how a powder will behave, how quickly moisture will move from one powder to another or at what water activity lumps and clumps will start to occur the best way is by creating a moisture sorption isotherm. 


Why does viscosity matter?

When producing a serum, syrup, gel or paste the viscosity can be important in several areas: 

·       The viscosity or “flowability” of a liquid informs of the pump strength required when moving the product through the production process

·       The filling nozzle size/flow rate of the filling head will be impacted by the viscosity 

·       Customer perceptions of quality are related to viscosity – a “watery” product is perceived to be of lower quality, regardless of the level of active ingredients.  


How is viscosity measured?

Viscosity is measured on a viscometer – an instrument that inserts a spindle into the liquid and then measures the resistance as the spindle turns.  The results are normally given in either centipoises or millipascals. 

The higher the millipascal/centipoise rating, the LESS “runny” (or viscous) a product is.

Water will normally have a rating of around 1 Centipoises, while a product like honey or chocolate syrup may be at about 10,000 Centipoises.  

Can I compare viscosities at different temperatures?

No, generally a liquid becomes “runnier” (or less viscous) as the temperature increases, but this relationship is not always predictable or linear.  The “normal” temperature for testing viscosity is room temperature, which is assumed to be 25⁰C.  If the viscosity needs to be tested at a specific temperature that is higher or lower than “ambient” then a viscometer with temperature control may be required. 


Can I test the seal integrity of blister packs?

Yes, blister packs, used to keep individual doses of medication or supplements safe until use can be tested for seal integrity using the “blue dye test” The test is made by submerging a package into a blue dye solution, the test chamber is placed under a vacuum that forces air from any openings within the pack. After returning to ambient pressure, the dye will penetrate and be evident within the pack should any holes be present. 

For consistent, reproducible and reliable blue dye tests Matt Solutions is able to supply and support the Dansensor H20. 

If the seal strength is important as part of quality control parameters or when designing new packaging, then the Danensor Lippke 5000 can help with Burst, leak, creep, bubble and combined test options 


What is a blue dye test?

A blue dye test refers to a commonly used method of checking the seal integrity of all types of blister packs used in the nutraceutical/pharmaceutical industry.  To complete a test, a sample blister pack in placed in a chamber with coloured water, a vacuum is drawn in the chamber and then released. 

If there are any leaks in the blister pack, the vacuum will draw the headspace gas out of the pack, and when the vacuum is released there will be the ingress of (easily visible) blue water. 

One instrument capable of completing a “blue dye test” is the Dansensor H2O


How do I tell if an instrument is CFR21 part 11 compliant?

CFR21 (Code of Federal Regulations title 21) Part 11 is a set of standards where electronic records and electronic signatures are considered trustworthy, reliable, and equivalent to paper records.  At its simplest level, compliance with the standard requires that records cannot be edited or changed after a reading/measurement has been taken. 

If compliance with CFR21 part 11 or GMP (Good Manufacturing Practises) is required as part of a HACCP, export requirements or supply agreement, Mätt Solutions would be most happy to hear from you and discuss how best to adhere to the requirements for specific production facilities. 

Is there a fast way to perform shelf-life testing / verification on nutraceuticals?

Mätt Solutions offer shelf-life testing services that look at the product's "complete picture", considering all its aspects to determine when and what ends the shelf life for supplements or nutraceuticals. Packaging provides protection from extremes in light, temperature, humidity and oxygen all of which will reduce shelf-life if not controlled. To perform an accurate shelf-life test, it is imperative to expose the product to different conditions to know when and why it fails.

Mätt Solutions have a wide selection of chambers and simulation set-ups to test these extremes and help determine the shelf-life and durability of nutraceuticals/supplements by offering both accelerated and real time shelf-life studies as applicable. The verification of label claims can be included in the shelf-life trial.  At the end of the trial, a comprehensive report is provided that states the actual shelf-life of the product, outlines reasons for failure and in most cases recommends ways to improve. This report tends to be a requirement by most supermarket chains and is well received by auditors and MPI (Ministry of Primary Industries)