Generally, a high-concentration aqueous sugar solution, milk, egg yolk, or a gelatinized starch solution is applied onto a surface of bread which is well baked and tinged with brown in order to improve a gloss effect, add flavor, and give softness and crumbliness to bread or stimulate appetite.
However, when milk or egg yolk is applied onto the surface of bread, the milk or egg yolk is readily exposed to microorganisms, and the like, thereby providing the optimum conditions for multiplication of bacteria. As a result, bread deteriorates and spoils rapidly, which makes it inappropriate for mass-production, and the milk or egg yolk also has a poor drying property and high permeability of being absorbed into bread. Owing to their physical properties, the milk or egg yolk should be applied onto the surface of bread in a state in which the bread is somewhat dried. Accordingly, production efficiency may be significantly reduced since a large amount of time is required to bake bread.
Also, the gelatinized starch solution has a problem in that it has a somewhat insufficient effect since starch has a property in which gloss fades away and finally disappears with time due to the aging of starch.
Further, the milk, the egg yolk, or the gelatinized starch solution has a basic restriction on its use since it has a property of changing colors of a crust of bread due to a browning reaction (i.e., a Maillard reaction) in which sugar components in the bread react with amino acids, and also has a problem of causing damage to unique tastes of breads.
Therefore, various types of gel-phase or liquid-phase glazing agents for baking bread, which prevent evaporation of moisture, give gloss, and preserve flavors by forming a protective film on a surface of bread or a surface of a fruit for topping bread, have been proposed.
For example, a method of manufacturing a gel-phase glazing agent for cakes disclosed in Korean Registered Patent Publication No. 10-0121138, a coating agent for bakery foods, and a bakery food using the same disclosed in Korean Patent Application Publication No. 10-2010-0090192, a liquid-phase composition for coating a baking product, and a method of preparing the same disclosed in Korean Patent Application Publication No. 10-2012-0131076, and a glaze for coating a bakery fruit including fructooligosaccharides, and a method of preparing the same disclosed in Korean Registered Patent Publication No. 10-1229996 are known.
However, such conventional glazing agents have a problem in that a hole of a coating/spraying nozzle or a sprayer may be blocked due to high viscosity and mucosity, and machine equipment may be contaminated, which makes it difficult to clean the equipment.
Meanwhile, pastry bread is made by wrapping a lump of milk fat or butter with dough, rolling out the dough thinly, followed by repeatedly performing this process to form thin layers of the milk fat and the dough. In this case, the pastry bread may generally have approximately 27 to 250 layers of grain, and may typically have a very crispy food texture and spicy and plain tastes when many laminated layers are formed by overlapping the dough and the milk fat several times.
Such pastry bread has problems in that, when a conventional transparent gel-phase or liquid-phase glazing agent for baking bread, which has high mucosity, is applied onto a surface of bread to give gloss to the surface of bread, the intrinsic shape of bread may be destroyed or the bread may collapse due to morphological characteristics in which an internal phase of bread is thinly layered, resulting in easy deformation and damage to the appearance of bread, and the glazing agent may have a negative influence on the intrinsic tastes and flavors of pastries, resulting in a decrease in product value.
Also, the conventional transparent gel-phase or liquid-phase glazing agent for baking bread has limitations in which, since a lot of bubbles are generated when a defoamant and the like is not added, bread has poor transparency, resulting in a remarkable decrease in gloss intensity, and is also inconvenient and cumbersome to use in that it should be heated to at least a predetermined temperature due to high mucosity, and then used in order to uniformly coat a surface of bread to a predetermined thickness.
Therefore, there is a demand for development of a glazing agent which has no syneresis, dripping or permeation, can preserve and maintain intrinsic tastes and flavors and characteristics of pastry bread without destroying a unique layered shape of the bread, can minimize generation of bubbles to maximize gloss intensity, and be directly applied onto a surface of bread without performing an additional process when applied to the surface of bread.