Fat – and its quality – can have a dramatic impact on animal health and performance. Oxidized fats reduce gut integrity, decrease feed palatability, create toxic metabolites, destroy fat-soluble vitamins and decrease performance. Minimizing fat oxidation is therefore crucial to successful animal production.
What causes fats to oxidize? Time of storage, application of heat and the mixing of different lipid sources all have an impact on fat quality, and specifically on influencing oxidation. Oxidation is an irreversible, naturally-occurring process where fatty acids are attacked by free radicals resulting in production of harmful byproducts, including peroxides and aldehydes. This process reduces the energy value of the fat and can have deleterious effects on growth performance. Once oxidation starts, the damage cannot be undone, so preventing oxidation should be a top priority for producers.
When it comes to fat quality, one often overlooked factor is the condition of the fat tank. Sludge buildup in the fat tank can dramatically reduce the value of even the highest quality fat during storage. To ensure your fat maintains its nutritional value, monitoring quality throughout storage and protecting fat with an antioxidant is critical to success.
Let’s take a closer look at the impact of the fat tank. All fats contain small amounts of sediment, which accumulate as “sludge” at the bottom of the fat tank. Over time, this sludge builds up, and a layer of residue coats the inside of the tank. These residues contain high amounts of free radicals which, once mixed with new fat, disperse and immediately promote oxidation of the new fat.
What can you do to make sure fat source quality doesn’t change during storage?
- Purchase high-quality fat, preferably from only one or two verified suppliers.
- Continuously monitor the quality of your fat. Testing the quality of fat from the delivery truck and from the fat tank is critical to see if your fat tank is negatively impacting quality.
- Stabilize your fat tank by adding an antioxidant system – such as RENDOX® – to your fat source.
- Clean your fat tank every 6 months to remove sludge and residues that contain free radicals.
- Do not mix different sources of fat in the same tank.
Recently, Kemin Customer Laboratory Services (CLS) completed a field study to determine the impact of an unclean fat tank on high quality, non-antioxidant treated fat and how implementation of a RENDOX® antioxidant system could impact quality of fat leaving the tank. The fat tank was sampled 3 times per week for three sampling periods (prior to antioxidant implementation, two weeks post-implementation and four weeks post-implementation). Samples were analyzed using three recognized quality tests for oxidative stability. The results are shown in Figure 1.
Figure 1. Oxidation analytical tests and change in oxidative status of poultry fat before/after implementation of an antioxidant system (n=3 for each designated time period).1
The results show that once high-quality fat was added to the untreated fat tank, blending of the fats allowed for the poor quality, free radical-loaded fat to immediately impact oxidation. The first sampling period confirms low OSI times and high levels of secondary oxidatives. After implementation of the RENDOX antioxidant treatment, OSI begins to increase – indicating improved stabilization of the fat. In addition, secondary oxidative levels begin to decrease, signifying interruption of the oxidative process.
Ultimately, to maintain animal performance and feed quality, both monitoring and protecting fat is key. Antioxidants quench free radicals to prevent oxidation and help stabilize and clean your fat tank over time. But remember, fats are highly variable, so choosing the right antioxidant for your fat source is just as key to your success. With more than 20 years of experience, Kemin has developed antioxidant solutions that will help your business succeed. For more information on how Kemin antioxidant solutions can help you maintain the nutritional value of your fats and oils, visit Kemin Animal Nutrition and Health – North America.
1. Do You Know What’s Happening in Your Fat Tank? A Fat Quality Case Study, 16-00129