TBHQ is an antioxidant and preservative used in unsaturated vegetable oils and many edible animal fats to extend storage life. The FDA has evaluated TBHQ and determined it is safe to consume at the concentration allowed in foods. The FDA sets an upper limit of 0.02% of the oil or fat content in foods. BHT is an antioxidant that is used to help prevent fats and oils from going rancid. Citric Acid is an acid that can be found in citrus fruits such as lemons and oranges or can be produced from different plant sources, including corn.