Non-Enzymatic Browning: Millard Reaction Nonenzymatic browning is found in food processing operations involving dehydration/ condensed milk. Nonenzymatic browning is purely chemical and occurs by several mechanisms. The Maillard Reaction is a chemical reaction between an amino acid and a reducing sugar, usually requiring heat.

Non-Enzymatic Browning: Millard Reaction Reducing sugars Amino compounds + Amines, amino acid, proteins Glucose, Fructose, lactose, Maltose Temperature Conc. of the reactants pH Inhibitors or preservatives Melanoidins

Non-Enzymatic Browning: Millard Reaction Browning reactions may be: - desirable to the food crust on baked goods, color of caramel, flavor, color of maple syrup - detrimental to the food darkening of dehydrated fruits , eggs, vegetables, canned or dried milk

Mix Well on a vortex mixer Read the Optical Density at 420 nm 30 min. 1 2 3 4 5 6 60 30 15 45 5 10 20 25 35 40 50 55 100ºC 50ْ Brix invert sugar (ml) 4 4 4 4 4 4 Mix Well on a vortex mixer 10% glycine 1 1 1 1 1 1 (ml) Read the Optical Density at 420 nm Buffer 1 1 1 1 1 1 (ml) pH 3 pH 4 pH 5 pH 6 pH 7 pH 8

Read the Optical Density at 420 nm 30 min. 7 60 30 15 45 5 10 20 25 35 40 50 55 Mix Well 1ml buffer pH 8 1ml 10% glycine 4ml 50ْ Brix invert sugar 70ºC Read the Optical Density at 420 nm

0.1g Sodium metabisulphate 30 min. 8 60 30 15 45 5 10 20 25 35 40 50 55 Mix Well 0.1g Sodium metabisulphate 1ml buffer pH 8 1ml 10% glycine 4ml 50ْ Brix invert sugar 100ºC Read the Optical Density 420 nm

Read the Optical Density 420 nm 30 min. 9 60 30 15 45 5 10 20 25 35 40 50 55 Mix Well 1ml buffer pH 8 1ml D.W. 4ml 50ْ Brix invert sugar 100ºC Read the Optical Density 420 nm

Read the Optical Density 420 nm 30 min. Blank 10 60 30 15 45 5 10 20 25 35 40 50 55 Mix Well 1ml buffer pH 8 1ml D.W. 4ml 50ْ Brix invert sugar 25ºC Read the Optical Density 420 nm

Results: Absorbance 420 nm Tube 1 2 3 4 5 6 7 8 9 Samar A. Damiati