density, in a fixed volume sample cell, instead of a
balance to determine mass.
It's low cost and nominal maintenance, make
it a perfect choice for field use.
In order to accurately perform an oven test (Loss on Drying) , as in ISO 6673 (Determination of Loss in Mass at 105 C) , extreme care must be taken in sample preparation, and testing. Because of the presence of volatiles (Oils and other evaporative compounds) the sample must be heated at low temperatures for 16 hours, as just part of the procedure, making it the least productive method for determining moisture levels. Moisture balances or Laboratory Fluidized bed analytical dryers can reduce the time to minutes instead of hours, but time is still a factor, and sample preparation and sample characteristic preservation, is still a big concern.
Capacitance based moisture analyzers are non destructive, indirect method instruments, with the ability to give an accurate moisture percentage reading in just seconds. They are used worldwide for agricultural applications, in grain elevators, processing facilities, exporting centers, etc...Because they do not heat the sample, loss of volatiles is not a concern.
NO WEIGHING OR SAMPLE PREPARATION REQUIRED.SIMPLY POUR THE SAMPLE TO THE ORANGE CAP, AND PRESS THE BUTTON. ACCURACY TO +/-.1% IN SIX SECONDS. OVEN TEST CORRELATION DATA ACCESSIBLE WITH INCLUDED SOFTWARE
Note: Do not use a compression cap type on brittle materials that will crack readily under slight pressure.
This Sinar AP 6060 Moisture Analyzer, because of its' accuracy, repeatability, and portability, is used worldwide by over 60% of the worlds' coffee buyers and sellers.
It is unique, in that its' programming features are accessible via sophisticated MNET Software. This allows users to create their own proprietary calibrations, as well as make adjustments for unique crops.
IMPORTANT: Capacitance based analyzers are indirect methods of moisture determination. They provide data values that, although precise, must be correlated to a direct method, such as Loss On Drying (Gravimetrics) or Karl Fischer Titration (Electro-Chemical Analysis), to give meaningful results. We recommend a moisture balance as an inexpensive, time saving, reference method, for occasional calibration checks.
In 2006, 'A comparative analysis of methodologies for water content determination in green coffee', was published in the Swiss Society of Food and Science Technology, (Juliana C.F. Mendonca, Adrianna S Franca, Leandro S. Oliveira), comparing results from Oven tests, Karl Fischer, and Infra-red Thermogravimetrics (Moisture Balances)
If steps are taken to minimize surface burn, reduce effects of color on heat absorption, and limit loss of volatiles, the results can be very accurate. Moisture balances utilizing mid wave infra-red heat waves accomplish this, as well as employing glass fiber sheets as a protective barrier on standard halogen heat lamps.