Shiro-an, white sweet bean paste for wagashi
Shiro-koshi-an, white bean paste
しろあん Shiro-koshi-an is the white and smooth variety of an or anko, sweet bean paste(shiro= white), it is made from white beans, called shiro-ingen-mame or oofuku-mame in Japanese. Shiro-ingen mame are the beans with richer and deeper taste, they are also called lima or butter beans. Oofuku-mame have finer texture and are called navy beans. Not every white bean is suitable for making shiro-an, there are few varieties of white beans in Japan, like tebou- daifuku- or shiro-hana mame; they all are recommended for wagashi recipes. The problem is, usually in Germany and other western countries the beans are named just “white beans” or “butter beans”.
There is a rather huge difference between shiro-an made with lima or navy beans. Lima beans are bigger(you also can strip the skin after soaking), they have a better, deeper taste (more “buttery”) and are much more suitable for fillings and baked wagashi. Navy beans are smaller, they have a very fine, smooth texture but are more bland, they are suitable for Wagashi like Nerikiri . Nerikiri is a dough similar to very fine almond paste (in texture, not taste) which is used to make Jo-namagashi, this are these wonderful looking small pieces of art. Such fine wagashi are suitable for the Japanese tea ceremony.
Shiro-an in general doesn’t have such a rich taste like red bean paste, but it is easier to cook(in my opinion), the taste also isn’t very “beany”, often people new to japanese sweets prefer shiro-an wagashi. The pure form isn’t used this much as filling, to improve the taste many different aromatic ingredients are added, like matcha(green tea powder) or salted cherry leaves(sakura-ha), such flavored white bean paste is then called matcha-an or sakura-an, other delicious kinds are miso-an(with mild white saikyo miso), kimi-an(with egg yolks), kabocha-an(with kabocha pumpkin) and few more.
How to make Shiro-an, white bean paste
Wash the beans, remove bad and brown exemplars, and soak the beans in plenty of water for at least 12 hours.The beans should be swollen to the maximum,otherwise the paste could get brown.
After the soaking, discard the soaking water, and if you use lima beans, strip the skins of . This is really easy to do, only a little time consuming, it will be also less work later(shiro-an made from lima beans is easier for beginners).
Place the beans in a pot with plenty of fresh water and bring it to a boil on middle heat. When it boils, add 200ml cold water, this improves the taste and makes the beans softer. Again, bring it to a boil, and add again 200ml cold water.
Let the beans cook at moderate heat, discard the foam. The beans will get wrinkles, and then will swell up to the maximum, which will last around 25 minutes (depending on the quality / age of the beans).
Now it is time for shibukiri, the bitterness is removed: turn the heat of, put the beans in a colander, drain the water, and wash with fresh cold water. Don’t let the beans get dry, (in case of navy beans) because they will crack, the beans should be always covered with water. The beans are still firm at this point and shouldn’t be cracked.
Beans contain tannins (bitterness), changing the water improves the taste very much. Same technique is used for example when cooking chestnuts (and, in case of the beans, also few other substances are removed, which are responsible for some “sounds” , I think you understand).
Then, place the beans back in the pot and cover with 900ml cold water. Let stand for 5 minutes. The degree of shibu-kiri determines the taste of finished anko: the longer it is, the milder but also more bland the taste will be ( also less “beany”).
Turn the heat on; bring the beans to a soft boil. Cook the beans in plenty of water; they should “dance” but not too much. Add fresh water if necessary, if you cook it in less water the beans will get brown. Put a drop lid(called otoshibuta) on the beans or a piece of parchment paper.
Now the beans are cooked soft, on middle heat. Depending on the size this will last around 1, 5 hours. Please don’t boil on too high heat, otherwise the beans will become mushy.Check if they are cooked, take 2-3 beans out and when they are tender enough to crumble easily between your fingers, they are done, then turn the heat off.
Now there are 2 possibilities: pour the beans through a colander with a cloth, and mash the beans with you hand, spread the cloth with the beans inside. Place the mashed beans in a large bowl, stir, and wash out the interior of the beans. First, push the beans through a coarse colander, the shells should remain inside; collect the liquid in a bowl (This is the more „professional“preparation).
Much easier way: drain the cooked beans, place in two or three parts in a food processor. If it is difficult to rotate, then add a little water. Break the beans, till you have a coarse paste. Place the mashed beans on a colander, and pour water over it, washing the starchy interior out. The skins should remain again in the colander; collect the “bean-liquid” in a bowl.
In both cases, after the skins are removed, you need to do it again with a very fine colander, to get a really smooth paste. Pour the liquid with the mashed beans through a very fine sieve, to remove the broken skins and all little pieces. Japanese wagashi chefs use a special one, called “umake no uragoshi” it is made with hair from horses. You could use a very fine flour sifter, this way you will have a very smooth and fine white bean paste.
Collect the strained liquid in a bowl. Add fresh water to the bowl, mix well and wait until the paste settles down. Discard the top water; be careful not to remove the sunken paste. Repeat this process 2 times until the top layer becomes clear.
Place a fine cotton cloth on a large colander and pour the liquid through the cloth. Close the cloth and turn, now you have to remove as much liquid as is possible, by squeezing it. Unfortunately, this is really hard work, you should use a very sturdy fabric. The crumbly mass in the cloth is called しろなまあん shiro nama-an, „raw bean paste“.
Finally, the last step: we need to boil the white bean mush with sugar. To get truly white shiro-an it is better to boil it with water and sugar.
Heat 70ml water and all sugar in a saucepan (preferably copper or with thick bottom), dissolve the sugar.Bring to a boil and add the half of raw bean paste, let it cook a little on high heat then add the remaining paste. Boil on high heat, keep stirring(this process is also calling “kneading”). The paste should thicken and start to get shiny, be careful not to burn it and keep stirring constantly. To get a nice shine stir more up and down, not in circles. Boil the paste down to the desired thickness. If you like to make nerikiri boil it little longer, it will get firmer. If you can shape a small „hill“(heap) then it is done. Place the hot bean paste in small portions on a tray or glass and let it cool. Store it packaged in refrigerator (3-4 days), but the best way is to freeze it in small portions.
IMPORTANT POINTS: to get a really white and smooth shiro-an, soak the beans in plenty of water for at least 12 hours. Some recipes call even for soaking the beans for 2 days, in a refrigerator in summer time. If they aren’t soaked well, they could get brown and the finished product will not be really white.
Please use white granulated sugar; even cane sugars with very light color could make the paste darker.
Also, please try to use navy or lima beans, not every kind of white beans is suitable. Don’t use old beans, they cook very uneven, it could happen one part is already mushy, other still firm.