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French Fries to Dairy DMI: Using an Inexpensive Air Fryer to Determine Dry Matter

French Fries to Dairy DMI: Using an Inexpensive Air Fryer to Determine Dry Matter

Measuring Dry Matter Accurately On-Farm With an Affordable Consumer Appliance

When assessing the health and productivity of your dairy herd, dry matter intake (DMI) is one of the key data points to consider. If DMI is low, productivity suffers no matter the quality of the ration. Moreover, with low DMI, maintaining cow health becomes that much more challenging.

Calculations and Costs

There are several ways to determine your herd’s DMI:

  1. Ration calculation — but unfortunately cows can’t read!
  2. Loaded and mixed Total Mixed Ration (TMR)
  3. Fed TMR and refusal rate
  4. Dry matter (DM) percentage of TMR compared with calculated DM percentage of TMR

Several conventional devices are available for DM determination, which in Europe cost in the range of €350-500 ($400-$575) per unit but even as much as $1200. Consulting nutritionists and feed mills also can provide DM data, yet this service often includes a significant cost. Having an easy-to-use, accurate – and most of all – affordable option can help dairy producers optimize productivity and maintain cow health. And it can help keep costs down, which is a great advantage in today’s global dairy market.

Enter the ordinary, inexpensive consumer air fryer, available at most home goods or kitchen appliance retailers. You might already have one in your kitchen at home now!

Air Fryer & Dry Matter
Use an ordinary kitchen scale to acquire consistently measured samples.

The 'Lightbulb' Moment

To explain the unexpected nature of our discovery, we turned to Peter van der Vegt, Diamond V’s Technical Sales and Support Manager based in The Netherlands. Here’s what Peter said. “It started with my wife looking for a way to incentivize our family to eat fewer unhealthy meals. To accomplish this, she purchased an air fryer for around €50 (about $60). The fryer uses hot air to ‘fry’ french fries or other foods without using boiling oil or fat.”

“It turned out that I didn’t really enjoy the taste of air-fried french fries,” Peter reports. “However, this unused kitchen appliance got Diamond V’s team in Europe wondering – if it can work on foods, could it help dry out other materials as well? What about corn, grass silage, or even a total mixed ration (TMR)?”

After a little experimentation, we found that by using the air fryer, we could accurately assess the percentage of dry matter present in a TMR or in the separate components of the TMR. Of course, there are many different consumer models, with varying degrees of automation and other optional features; but they all work roughly the same way.


Here is our usual method for determining DM with the air fryer, which we call the “Diamond V Dry Matter Processor”:

Generally, we start by taking a measured sample of material, for instance 100 grams. We put this material in the fryer for 30 minutes at 120° C or about 250° F, and then remove it and weigh it again. If the sample now weighs 40 grams, for example, the percentage of dry matter is 40%. Starting with a 100-gram sample makes the calculations easy, even for those of us for who may be math-challenged.Air Fryer Method to Determine Dry Matter

Results and Follow-Up

The Diamond V European Team test the air fryer method with over 100 samples and followed up with contra-testing of several samples. We found that the method is strikingly accurate, showing less than a 1% variance when compared to DM determination with other devices. This accuracy makes the method suitable for on-farm use at a much lower price point than comparable methods

Working closely with some leading European feed manufacturing and premix companies, we introduced the “Diamond V Dry Matter Processor” in Europe. For instance, during Dairy Academy sessions with over 80 field technicians and dairy farmers in the Netherlands, the method received rave reviews. Now Key Performance Indicators (KPIs) related to DMI can be measured accurately and affordably!

This concept was picked up by media in the Belgium-Netherlands-Luxembourg (BeNeLux) region, and TopAgrar, a leading German agricultural magazine. Diamond V also demonstrated air fryer DM determination at the 2018 World Dairy Expo in Madison, Wisconsin. To see a video of the air fryer method, take a look at Progressive Dairy’s coverage here.

As Diamond V conducts TMR Audits™, the Diamond V Dry Matter Processor is now part of the toolkit we use when step on a dairy farm.