Ginger milk curd

Ginger milk curd, also known as ginger-juice milk curd, ginger milk pudding or simply ginger milk, is a Chinese hot dessert originated in Shawan Ancient Town, Panyu District, Guangzhou in the Guangdong Province^[1][2] in southern China. The main ingredients are ginger, milk, and sugar.^[3] Water buffalo milk is used in the original recipe.

Ginger milk curd

Alternative names	Ginger-juice milk curd, ginger milk pudding, ginger milk
Type	Pastry
Course	Dessert
Place of origin	China
Region or state	Shunde
Main ingredients	Ginger, milk, sugar
Media: Ginger milk curd

Ginger milk curd
Traditional Chinese	薑汁撞奶
Simplified Chinese	姜汁撞奶
Literal meaning	Ginger collides with milk
Transcriptions Yue: Cantonese Jyutping goeng1 zap1 zong6 naai5

Underlying biochemical principle

The most important part of the ginger in ginger milk curd is the ginger protease zingipain. This substance with molecular weight of 31 kDa is found with three forms of isoelectric point values around 5.58, 5.40, and 5.22, respectively. The three forms have very similar biochemical behavior, where the optimal proteolytic activity is 40–60 °C (104–140 °F) and maximum clotting activity at 70 °C (158 °F). However, clotting decreases significantly at temperatures of 75 °C (167 °F) or above.^[4]

Milk is a substance consisting mainly of milk fat globules and casein micelles in a continuous phase of water, sugar, whey protein and minerals. Casein micelles consist of mainly α(s1)-casein, α(s2)-casein, β-casein, and κ-casein, where hydrophobic α and β-casein are in the inner sub-micelle and hydrophilic κ-casein is in the outer part.

When the milk starts curdling, the curds are small, but as coagulation increases, curd size increases until the milk ends up with a tofu-like structure.^[5] When the curdling occurs, the ginger protease cuts open the κ-casein so that the hydrophilic C-terminus and the hydrophobic N-terminus separate. This disrupts the stability of the casein micelle. In the hydrophobic effect, the hydrophobic casein coagulates.^[6]

See also

• Douhua
• Junket (dessert)
• List of Chinese desserts
• List of desserts
• Food portal