If you want to keep the original color, you can add a small amount of monascus powder to add color to the dough. Monascus powder is a natural pigment fermented by monascus in rice, which is harmless to the body and can be eaten by the general population.

The reason why pitaya changes color when heated is that pitaya contains anthocyanins, which will decompose and naturally change color when heated.

Nowadays, there are two kinds of edible pigments in common use: natural pigments and synthetic pigments. Natural pigments are derived from natural materials, mainly extracted from plant tissues, and also include some pigments from animals and microorganisms. Synthetic pigment refers to the organic pigment prepared by artificial chemical synthesis, which is mainly made of aniline dye separated from coal tar.

Principle of use

The international management of natural pigments is not very strict. In the use of pigments, as long as you remember three principles, you can proceed smoothly. These three principles are:

(1) Choose natural pigments widely recognized in the world;

(2) Coloring foods that can be colored in various countries;

(3) The amount of pigment added in food color matching should be lower than the control of the highest content. For example, beetroot extract is a natural pigment, which is allowed to be used in Sweden, but it is only allowed to be used in special foods, such as candy, flour, cakes and edible icing, and its usage is also limited. The dosage in edible icing should not exceed 20 mg/kg (calculated by beet red).

References:

Baidu encyclopedia-pigment