The document discusses oxidants and antioxidants. It defines oxidants as substances that can oxidize other substances by removing electrons, and provides examples like reactive oxygen species. It then discusses sources of oxidants like metabolism and pollution. It defines antioxidants as substances that reduce oxidation reactions and lists endogenous and dietary antioxidants like vitamins C and E. It outlines some consequences of oxidant action like lipid peroxidation and DNA damage.

1. MOCK TEACHING UiTM “ REVIEW OF OXIDANTS AND ANTIOXIDANTS” NURHAFZAN ANIS ISMAIL

12. Examples of antioxidants Antioxidants Sources Vitamin A and Carotenoids Carrots, broccoli, sweet potatoes, tomatoes, peaches and apricots. Vitamin C Citrus fruits like oranges and lime etc. green peppers, broccoli, leafy vegetables and tomatoes. Vitamin E Nuts and seeds, whole grains, green leafy vegetables, vegetable and liver oil. Some common phytochemicals Flavonoids (soy, red grapes, tea) Lycopene (tomatoes) Lutein (dark green vegetables e.g.: spinach) Lignan (flax seed, oatmeal, barley) Vitamin-like antioxidants Coenzyme Q 10 (CoQ 10 ) Glutathione

15. ADVANTAGES AND DISADVANTAGES OF NATURAL AND SYNTHETIC ANTIOXIDANTS Synthetic Antioxidants Natural Antioxidants Inexpensive Expensive Widely applied Use restricted to some products Medium to high antioxidant activity Wide ranging antioxidant activity Increasing safety concern Perceived as innocuous substances Use banned for some of them Increasing use and expanding applications Low water solubility Broad range of solubility Decreasing interest Increasing interest

16. METHOD OF PRODUCING STABLE FOODS/PRODUCTS WITHOUT ADDING ANTIOXIDANTS Techniques Methods Elimination of oxygen Packaging under nitrogen; packaging in vacuum; packaging with an oxygen scavenger. Elimination of sensitive substances Replacement of polyunsaturated oils with oils which less unsaturated and more stable, such as olive oil or palm oil. Decreasing the rate of oxidation Storage at low temperature; storage in the dark; use of fats and oils that contain low levels of oxidation promoters (e.g.: oxidised products and heavy metals); use of ingredient that are naturally rich in antioxidants.

22. QUESTION AND ANSWER SESSION THANK YOU FOR YOUR KIND ATTENTION