Every week, I make about 500gram worth of soy bean milk since Piglet and I are a fan of it.
Previously I have been using gypsum powder which is actually food grade magnesium calcium sulphase. It is a material used for plaster ceiling. I prefer not to use it as one of the health risk is kidney stones.
A few weeks ago I bought GDL at the baking shop to try making tau foo fah. According to Wikipedia, GDL (Glucono Delta Lactone) hydrolyses to acid on addition to water and is 1/3 the sourness of citric acid.
I started off using the recipe from Wendy and made adjustments along the way. After about 3 weeks, I have figured it out.
Tips

- Require exact amount of GDL. It is adjusted according to the soy bean content. Too little: breaks into brittle pieces. Too much: A thick layer of water on top and taste sour.
- Small amount of water to dissolve GDL.
- Optimal temperature 80-90 degree celcius
- Let it rest (undisturbed) after stirring
Experiments
I’ve also conducted a few experiments:
| 1 | Reducing soy bean milk batch I started with 750ml, managed to reduce it first to 500ml, then 250ml then 190ml (rice bowl) |
| 2 | Omitting corn starch |
| 3 | Pour soy bean milk technique. Pour soy bean milk Pour soy bean milk and Stir Pour soy bean milk from 1 feet high |
It made no difference for all above.


My Tau Foo Fah Formula:
| Formula | Example | |
| GDL / Soy bean | 2.4% | 3g of GDL (1/2 tsp) for 125g of Soy bean |
| GDL / Soy Bean Milk | 0.3% | 3g of GDL (1/2 tsp) for 1L of Soy Bean Milk |
| GDL/ water to dilute | 20% | 3g of GDL (1/2 tsp) mix with 15g (1 tbs) Water |
| Temperature | 89-90C | |
| Technique | Mix GDL and Water in bowl. Pour Soy Bean Milk |
Tau Foo Fah Recipe
- Boil 1L soy bean milk
- Leave soy bean milk aside for 5 minutes or until temperature reduces to 90C
- Mix ½ tsp GDL with 1 tbs Water in a bowl
- Pour soy bean milk into bowl
- Cover with a cloth and cover for 20-30 minutes
- Scoop it and enjoy with sugar syrup
The ‘lazy’ way
I take about 200ml of soy bean milk from the fridge, microwave it in a mug until its bubbling. Pour it into a rice bowl containing less than 1/8 tsp & ½ tsp water. And it’s a single serving of tau foo fah.