There are four purposes of adding the alkaline water:
One is to neutralize the acid in the transformed syrup, preventing the mooncake from producing a sour taste and affecting the taste and texture;
Two, to control the speed of oil return and regulate the softness and hardness of the cake crust;
Three, is to increase the alkalinity of mooncake crust, which is good for the coloring of mooncake; the higher the alkalinity, the more colorful the crust will be;
The fourth is that the alkaline water is neutralized with acid to produce certain carbon dioxide gas to promote moderate expansion, making the texture of mooncake crust more loose and deformed. The neutralization reaction between the water and the acid produces a certain amount of carbon dioxide gas, which promotes the moderate expansion of the mooncake, making the mooncake crust taste more fluffy and not deformed.
Expanded Information:
San (jian) water, also known as lye, or edible san water, is a compounded food additive, a material used in food technology, and a traditional accessory common to Cantonese-style pastries.
Significance
Alkaline water is often added when making the dough for the crust of Cantonese moon cakes.
According to the national standard for mooncakes, the production of Cantonese mooncakes requires the use of spout, which is a specialty of Cantonese mooncakes.
In the new version of the Standard for the Use of Food Additives introduced on June 20, 2011, this ingredient is not included in the list of permitted additives.
A substance called "spout" is often added to the dough of Cantonese mooncake crusts. Alkaline water is a traditional auxiliary ingredient common to Cantonese-style pastries. It is an alkaline solution obtained by our ancestors by boiling grass ash with water for one day and taking the supernatant, which has a pH value of 12.6. The main components of grass ash are potassium carbonate and sodium carbonate. In the absence of modern chemical alkali in history, this kind of plant alkali prepared by local method had to be used.
Related regulations
According to the national standard "mooncake" on the definition of Cantonese mooncake is to the Guangdong region production process and flavor characteristics represented by the use of wheat flour, transformed syrup, vegetable oil, alkaline water (Alkaline) made of pie crust, through the filling, shaping, brushing the egg, baking and other processes processed by the texture of the soft mooncake. This means that the alkaline water can be used in the production of Cantonese-style mooncakes.
On June 20, 2011, a new version of the "Standard for the Use of Food Additives" was introduced, specifying 27 additives that are prohibited in the production of mooncakes and strengthening the management of the use of additives in compounding, of which, spout was not included in the new version of the standard for the use of food additives.
The State Administration of Quality Supervision, Inspection and Quarantine (AQSIQ) has also publicly replied on its website that "Custard powder and alkaline water (lye) are not included in the substances of GB2760-2007, and are not allowed to be used as food additives".
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