THE WORLD LEADER IN EQUINE FEED PRODUCTION

Our Processing Methods Explained

Depending on the processing method, your feed may look different—pellets, flaked grains, or extruded nuggets. Is that just aesthetic, or do the shapes have nutritional benefits? What does processing mean, and how does it help your horse’s health? This short article answers all these questions. It highlights the three main processing techniques at the HYGAIN® equine-only feed mill and explains their differences and benefits.

What exactly is processing?

Processing is the treatment of grains into dry or wet conditions by steam flaking, pelleting, or extrusion to improve digestibility. It can happen by mechanical methods (rolling or grinding), thermal methods (roasting or micronizing), or thermo-mechanical methods (flaking or extruding). But don’t confuse the processing of your horse’s feed with processed foods for humans—which calls to mind unhealthy fast food with additives and preservatives.

Why process grains?

Your horse’s digestive system will thank you for it. Factors affecting nutrient absorption from grains include the level of intake, the actual ingredient (e.g., oats, barley, corn) and how the grain was processed. The processing of grains is applied to maximize the small intestine digestibility of the grain in order to reduce the risk of digestible disorders while increasing the nutritional value of the feed. The higher the digestibility of the grain, the more glucose and energy will be absorbed in the small intestine.

Pelleted, extruded or micronized?

Thermal processing uses heat to “pre-digest” the grains. Like a natural digestive enzyme, heat breaks down the complex carbohydrate bonds of the grain starch. This “gelatinization” of the starch increases the availability of nutrients, such as glucose, in the small intestine.

In the pelleting process, the ingredients are ground and then steam-heated to 176–194°F for about 20 seconds. Next, the mash is pushed through a pellet die, cooled, and dried to prevent mold growth. With forage pellets, the forage is dehydrated before being processed. As pellets are cooled, moisture content reduces.

The extrusion process begins with grinding and mixing ingredients such as grains, oil, and fiber sources. The resulting mash is cooked using a combination of high-temperature steam and pressure. This process involves pushing the mash through an extruder–a steel cylinder–where the mix is rotated under increasing pressure. The end product emerges from the extrusion die and is cut into small cubes or nuggets. In this stage, it expands and “pops,” like a kernel of corn. These pieces cool before being bagged. Due to the higher temperatures and added pressure, the gelatinization of starches is even more complete with extrusion than with pelleting. Extruded products transform into a soft mash with added water and are ideal for horses with poor dentition, such as senior horses.

During the micronizing process, infrared heat warms the grain until all moisture is vaporized (generally taking less than a minute). This process ruptures the grain’s endosperm, reconfiguring the grain’s starch structure (gelatinization). The grain then becomes soft and pliable. Immediate flaking further gelatinizes the starch and significantly enhances the feed’s digestibility and nutritional value.

Micronized grains – starch gelatinazation

Research shows that the starch in micronized grains can be up to 95% digested in the horse’s small intestine. The starch in whole, cracked, and steam-rolled cereal grains, such as barley and corn, is only 20–40% digested.