午夜福利1000集合

STALE bread may seem like it has simply dried out, but staling is actually a complex process that .

In the 19th century, the French chemist Jean-Baptiste Boussingault noted that stale bread can be refreshed by putting it in the oven, and showed that bread will still go stale if it is hermetically sealed and doesn鈥檛 lose any moisture.

In fact, staling is to do with the chemistry of starch, which is found in flour and consists of two kinds of sugar molecules, amylose and amylopectin. Raw starch has a rigid, crystalline structure, but it absorbs water and forms a gel when cooked.

In the hours and days after a loaf is baked, this gel-forming process is reversed: the water slowly moves back out of the starch granules and they recrystallise, making the bread firmer.

If the loaf isn鈥檛 very old, the water remains in the bread and staling can be reversed by heating it up again. This is why stale bread makes perfectly decent toast. There are plenty of other ways to make use of stale bread, such as the Tuscan soup ribollita, and panzanella, a salad in which croutons are soaked in dressing.

Bread goes stale most quickly just above freezing temperature, so keeping bread in the fridge isn鈥檛 advised unless you plan to toast it. Commercial loaves will usually contain added emulsifiers that inhibit staling, probably by interfering with the movement of water out of the starch granules.

Another way to make bread that stays soft for longer is using a technique known by the Chinese name tangzhong, or the Japanese name yudane. It involves heating up some of the flour with water to 鈥減re-gelatinise鈥� the starch before baking. When heated above 65掳C, starch granules can absorb much more water and they hold onto it for longer, even after baking.

This technique is used to make Japanese milk bread, a soft and slightly sweet loaf that stays fresh for several days. The dough used for this bread is also enriched with butter, milk and egg. The fats they provide limit the development of gluten, which helps give this bread its tender and fluffy texture.

To make your own milk bread, start by whisking the tangzhong ingredients together in a small saucepan, then place the pan on a low heat and keep whisking for 3 to 5 minutes until the mixture is thick. Then whisk in the rest of the milk, the egg and the melted butter.

In a bowl, combine the flour, sugar, salt and yeast, then add the mixture from the pan. Mix it all together, and knead until you have a smooth dough that can be stretched thin. Leave it to rise in a warm place for 60 to 90 minutes.

Divide the dough into quarters, then flatten each piece and roll it into a log. Place the logs, seam side down, in a greased loaf tin (12 centimetres by 24 centimetres). Brush the tops with egg, then bake at 180掳C for 30 minutes.

What you need

Tangzhong:

3 tbsp milk

3 tbsp water

2 tbsp bread flour

Dough:

300g bread flour

50g sugar

1 tsp salt

7g instant yeast

1 egg

50g butter, melted

100ml milk

These articles are posted each week at