Manufacturing a glazing agent bread or pastry products maintaining intrinsic tastes and flavors without destroying unique layered shape or collapsing the products. First prepare solution A by mixing 3 to 4 parts weight refined sugar and 0.5 to 1.5 parts weight amidated pectin, add 27 to 28 parts weight purified water, and dissolve at 80 to 85° C. for 20 to 25 minutes, second prepare solution B by mixing 0.2 to 0.3 parts by weight citric acid, 46 to 48 parts by weight starch syrup and 0.02 to 0.05 parts by weight black rice flavoring, adding 20 to 21 parts by weight purified water, heating at 60 to 65° C. for 10 to 15 minutes to dissolve, and third gelling the solution A and solution B by heating at 90 to 95° C. for 20 to 25 minutes to gel, and cooling the resulting mixture to room temperature.