【石灰水】Limewater/Air Kapur

石灰用于食品加工很常见，例如石灰水泡柿子，制作皮蛋、冰粉、米豆腐等等。在国外，石灰也是腌渍食品制作时的常见用料，石灰在食品加工里能起保鲜，杀菌消毒的功能，所以运用广泛。

石灰和石灰水在东南亚的传统美食里也用得非常多，比较常见的做法是用石灰水浸泡一些需要长时间烹煮的蔬果，让其在烹饪过程中仍然可以保持形状和颜色。

另外一个更接地气的用法就是加到面糊里制作脆浆，加入石灰水制作的挂浆可以长时间保持爽脆的口感，不容易回潮，效果非常棒。

使用少量石灰制作的食品对身体无害，微量的石灰摄入甚至还有补钙的效果，但切记使用不能过量，购买的石灰也必须是食品级的才行噢！

自己在家制作石灰水超级简单直白，只要找到原材料食品级石灰，基本就是三十秒即可搞定的事情，制作一次还可以用上好多好多年，有兴趣的朋友可以试试看。

注：食品级石灰膏可以在网上，亚洲超市，印度超市，墨西哥超市里找到。就是印度人嚼槟榔时抹到荖叶上的白色膏状物质。

Limewater is used in many Malaysian dishes to help retain shape of fruits/vegetables during cooking process, it is also the secret ingredient in making the batter for fry foods batter that stays crispy for a long time.

Some people back in Malaysia add Slaked lime (Kapur Sirih) or Calcium hydroxide into frying batter to achieve the crispy effect, I personally like to use limewater in my batter since it is colorless and odorless and doesn't change the ratio and consistency of my batter at all.

Making limewater at home is really straight forward and simple, as long as you can get hold of the main ingredient - - Slaked Lime, sometimes also called Pickling lime, Kapur Sirih in Malay, Nam Pboon Sai   น้ำปูนใส in Thai, "Cal" in Spanish.

Slaked Lime is the main ingredients in the Paan/betel chewing practice, so you can easily find this ingredient at any shops that sells Paan/Betel nuts. 

(Hint : Try a traditional Indian grocery shop, Hispanic grocery store or Thai/Vietnamese Grocery stores. Just make sure you purchase food grade lime, not the one for construction use, which may consist lead.)