Purchasing quality fat is the first step in limiting the potential impacts of oxidation. However, high quality fat can easily be negatively impacted due to handling and storage conditions. Time of storage, application of heat and the mixing of different lipid sources all have direct implications to the production of peroxidation compounds.
Management practices implemented often focus on the amount of time fat is exposed and susceptible to oxidation. Unfortunately, this practice does not take into account the layer of fat residue, which coats the inside of the tank, or the sludge buildup at the bottom 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.
Treating fat with a Kemin antioxidant system will prolong the fat quality, ensuring you receive the maximum value from your fat.
Previous fat quality testing indicated the customer feed mill was receiving high quality, pet-food grade, non-antioxidant treated poultry fat. The customer's fat tank was not being cleaned, causing concern that the quality of the fat leaving the tank was not the same as the quality of the incoming fat.
As the results of the field demonstration indicate, once high quality poultry 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 series of samples confirm low OSI times and high levels of secondary oxidatives. After implementation of the antioxidant treatment system, OSI begins to increase, indicating improved stabilixation of the fat. In addition, secondary oxidative levels begin to decrease, signifying interruption of the oxidative process.
Stabilizing the quality of the previously untreated fat tank takes time. Even as new fat is added, OSI times and secondary oxidative levels continue to improve.