The second method we use is an electric current reader. This instrument works in a very different way. First we weigh out exactly a 250.0 g sample of wild rice. You see the weigh scale on the right hand side in the picture. The wild rice goes in the white holder. |
||||||||||||
Then we pour this sample into the column on the left side of the instrument. Next, we switch on the instrument and it forces a small electric current through the wild rice. The more water in the wild rice, the more the current flows through it.
In the middle of the instrument, you can see a white half-circle window. In this window a needle points to how much electric current is passing through the wild rice. The needle tells us the current, but the instrument doesn't calculate the % of water content. This calculation has been done ahead of time for different amounts of current, and the results were printed in a table of numbers. You can see this table of numbers in front of the instrument. We read this table to get the % water content in the wild rice. This instrument has about the same reliability as the other one if all the measurements are carefully made. From start to finish, this method only takes 20 seconds. When we're in a rush, we use the second method. But because it is new to us, we often double check our observations by using the first method from time to time. When the same sample of wild rice is analysed both ways, the results are usually within 0.4% of each other, as we would expect. |
||||||||||||
|
||||||||||||
Click on a page number to move within the site. |