NonEnzymatic Browning Millard Reaction Nonenzymatic browning is found
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 Glucose, Fructose, lactose, Maltose + Amino compounds Amines, amino acid, proteins Temperature Conc. of the reactants p. H 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
30 min. 1 55 60 5 10 50 45 15 40 20 35 30 25 2 3 4 5 6 100ºC 5 Brix invert sugar (ml) 4 4 4 a vortex 4 4 4 Mix Well on mixer 10% glycine 1 1 1 Read the Optical Density at 420 nm (ml) Buffer (ml) 1 p. H 3 1 p. H 4 1 p. H 5 1 p. H 6 1 p. H 7 1 p. H 8
30 min. 7 55 60 5 10 50 45 15 40 20 35 30 25 Mix Well 1 ml buffer p. H 8 1 ml 10% glycine 4 ml 5 70ºC Brix invert sugar Read the Optical Density at 420 nm
30 min. 8 55 60 5 10 50 45 15 40 20 35 30 25 Mix 0. 1 g Sodium metabisulphate 1 ml buffer p. H 8 1 ml 10% glycine 4 ml 5 100ºC Well Brix invert sugar Read the Optical Density 420 nm
30 min. 9 55 60 5 10 50 45 15 40 20 35 30 25 Mix Well 1 ml buffer p. H 8 1 ml D. W. 4 ml 5 100ºC Brix invert sugar Read the Optical Density 420 nm
Blank 10 30 min. 55 60 5 10 50 45 15 40 20 35 30 25 Mix Well 1 ml buffer p. H 8 1 ml D. W. 4 ml 5 25ºC Brix invert sugar Read the Optical Density 420 nm
Results: Tube Absorbance 420 nm 1 2 3 4 5 6 7 8 9 Samar A. Damiati
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