Name: Grain Sampling Probe
Cost: around CAD$ 400 to 600
Available at: Manufacturer’s website
Intended use
Grain probes are used for representative sampling of various granular materials, such as grains and dry foods. Results are taken at various levels from stockpiles, bags, drums, bins, and mixers. The samples can be used to run a mixer uniformity test in the feed industry.
How does it work?
Grain probes vary in design and length. Short probes are more commonly used when sampling from drums and bins, while longer probes are optimal for sampling from larger stockpiles such as barges, railcars, large trucks, feed mixers, and hoppers. The grain probe should be long enough to penetrate at least 3/4 (75%) of the depth of the feed. There are a variety of grain probes, such as open-handled probes, partition/compartment probes, and spiral probes. Open-handled probes are used to take feed and grain samples from the entire depth of a container. The contents of the probe are emptied from the handle end and then can be mixed to get a representative sample. Spiral probes are designed to allow openings on the inside tube to rotate, opening first at the bottom and then in gradual steps to the top, which guarantees a sample from the bottom up. Partition probes individually separate each sample across the depth of the container. These probes consist of two tubes, one inside the other. The inner tube is divided into compartments (individual openings) that allow collecting samples across the profile (depth) of the container to detect inconsistencies in feed quality.
Using the device
If the intention of the test is to evaluate feed quality across the container depth, use a partition probe to take samples from different levels of the batch. Push the probe into the container to take the sample, and then empty the probe onto a tarp or trough and inspect it. You can then mix the samples taken from each level (compartment of the probe) together and mix thoroughly before transferring them to their containers.
To take feed samples from a horizontal mixer (for example, to run a feed mixing uniformity test), a spiral or an open-handled probe can be used. Take samples from 10 different locations in the mixer (Figure 1). To take the sample, push the probe in your sample and open the compartments to simultaneously take a sample throughout the entire probe. Then close the probe, pull it out of your sample, and dump your sample through the handle. Empty the contents of each probe into a container and repeat the sampling to collect about 500 grams of sample from each location. Mix the contents of each probe location together prior to reducing the final sample size. To reduce the sample size, spread the mixed sample from each location of the mixer on a clean plastic or paper to form an even layer. Then split each sample into quarters (Figure 2). Take two opposite quarters, mix, and repeat until the two quarters selected give the desired sample size (usually 100 grams). Put the final samples in plastic bags, zip-lock bags, paper bags, or plastic containers with lids and label them with the sampling date, sample number, and contents. Store the samples in a cool and dry location before being shipped to the lab for nutrient analysis. To interpret the nutrient results for the feed mixing uniformity test purposes please check this article!
References
Herrman, T. 2001. Sampling: Procedures for Feed. MF-2036. Kansas State University Agricultural Experiment Station and Cooperative Extension Service Bulletin (Link)
Herrman, T. and K. Behnke. 1994. Testing mixer performance. MF1172. Kansas State University Agricultural Experiment Station and Cooperative Extension Service Bulletin, Manhattan, KS: Kansas State University (Link)
