Summer is Coming: Are Your Fats and Oils Protected from Oxidation?

Implementing an Oxidation Control Plan

Oxidation control starts with purchasing high quality fats and oils. However, even high-quality fat can be negatively impacted due to handling and storage conditions. Time of storage, application of heat and the mixing of different lipid sources can all directly impact production of toxic oxidation compounds. Further, oxidation is an irreversible process; so, once oxidation damage occurs, it cannot be undone. Evaluating oxidation damage and protecting supplemental fats and oils from oxidation are critical components of an oxidation control program.

How do we evaluate oxidation damage of fats and oils?

Both chemical and physical methods are used to assess the quality of feed ingredients. Unfortunately, common fat quality measures – like color, moisture, insolubles, free fatty acid content, etc. – do not necessarily characterize oxidation damage.² The oxidation process results in specific primary and secondary degradation products – peroxides and aldehydes – which are produced at different stages of oxidation. Analysis of these molecules provides producers with a snapshot of the current state of oxidation damage in their fats and oils. However, it’s important to measure multiple oxidation products, as a single indicator – like peroxides – may not adequately characterize the extent of oxidative damage.^1,3

How do we protect fats and oils from oxidation?

Antioxidants are molecules added to fats, oils and feed ingredients to help reduce lipid oxidation.

Antioxidants work either by sacrificing themselves to quench free radicals before fatty acids can be attacked (primary antioxidants) or by chelating pro-oxidant metal ions and acting as oxygen scavengers (secondary antioxidants).⁴

When using an antioxidant, it’s important to remember that it cannot reverse oxidation that has already occurred. However, combinations of certain primary and secondary antioxidants can be more effective in preventing lipid oxidation than the individual components.5

Are all antioxidants equally effective?

The short answer is NO. The effectiveness of an antioxidant depends on multiple factors including the substrate, antioxidant dose, chemistry synergy and time and place of application. Research has shown that TBHQ and propyl gallate are more effective for vegetable oils; whereas, BHA and BHT are most effective when used in saturated animal fats.^5,6 Considering the wide variability in fats and oils used today – poultry fat, restaurant greases, corn oil, etc. – would you trust a single antioxidant to protect everything  or have oxidation control solutions designed specifically with fat variability in mind?

Kemin oxidation control solutions

The best way to protect your fat from negative oxidation effects is to use an antioxidant system. An antioxidant system should contain a combination of the following:

• Synergistic blend of antioxidants to absorb free radicals before they destroy fatty acids
• Metal chelators to bind metal ions, which may promote free radical oxidation
• Oil-based carriers to better mix with fat molecules

With more than 50 years of research and development experience in the animal feed industry, Kemin offers research-backed natural and synthetic antioxidant systems – including non-ethoxyquin options – that are specifically designed for different fats and oils. 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 at kemin.com/feedquality.

References

¹Hung, Y.T., et al. 2017. Peroxidized lipids reduce growth performance of poultry and swine: A meta-analysis. Animal Feed Science and Technology, 231:47-58.
²Shurson, J. and B. Kerr. Fat, oxidation and the swine diet. National Hog Farmer, July 19, 2018.
³Shurson, J., et al. 2015. Evaluating the quality of feed fats and oils and their effects on pig growth performance. Journal of Animal Science and Biotechnology, 6:10.
⁴Kerr, B., et. al. 2015. Characteristics of lipids and their feeding value in swine diets. Journal of Animal Science and Biotechnology, 6:30.
⁵Budilarto, E.S. and Kamal-Eldin, A. 2015. The supramolecular chemistry of lipid oxidation and antioxidation in bulk oils. Eur. J. Lipid Sci. Technol., 117:1095-1137.
⁶Comparative antioxidant efficacy of the antioxidants BHA, BHT, MTBHQ and ethoxyquin, BB-03-00649.