Saturday, February 09, 2008

Daikon Simmered with Hotate

Daikon Simmered with Canned Hotate (Scallops)
with Blanched Komatsuna on the side

When making a simmered dish with daikon radish, it is generally recommended to pre-boil it with a little amount of raw rice or in rice rinsing water until a toothpick can be inserted easily. It is a well-known tip here in Japan, but most of us do not know the scientific reason behind it (or if there is one at all). So, having been triggered by a question from someone who read my buri-daikon post, I did a bit of net research. Let me share the result with you.

In a nutshell, the pre-boiling process mentioned above is supposed to remove the slight bitterness or harshness of daikon and make simmered daikon soft and tasty. They say that adding rice, or using rice rinsing water for this process means boiling daikon in a colloid solution, and the bitter substance contained in daikon will be adsorbed onto the colloidal particles during this process.

If a colloid solution is the key, then can’t we just add regular wheat flour or corn/potato starch in place of raw rice? Well, some Japanese websites say that a little amount of wheat flour will do, but I found one person saying that it’s not a good idea because wheat flour contains some protein (but didn’t really mention how that protein negatively affects this process). And more than three people wrote that if used potato starch, the simmering water will turn into glue, which I totally agree with. (I mean, if used too much of it.)

On the other hand, some people do say that using raw rice or rice rinsing water is not necessary; pre-boiling in regular water is just fine. Or some even say that pre-boiling is not necessary at all because these days daikon radishes do not have such strong bitterness. Confusing, isn’t it?

What I do -- as a sort of compromise solution-- is: do pre-boiling for simmered daikon dishes with light seasoning, and skip it for those with heavy seasoning. To me the best example for the former is furofuki-daikon, and the latter is oden or buta-bara daikon (daikon simmered with pork ribs). I put buri-daikon (daikon simmered with yellowtail) in the former category, because the fish has the risk of giving an unwanted fishy flavor to the dish, so I don’t want any additional unwanted flavoring from the daikon. Personally, I believe that this pre-boiling trick makes a big difference when you want to enjoy the delicate taste of daikon itself with light seasoning.

Now, I was also asked for a tip to avoid bitter daikon and choose good ones. But sorry, I still cannot find an answer. The problem was that there were many websites talking about the “pungency” of daikon, but not exactly about the “bitterness.” They say that the pungency is caused by a substance called isothiocyanate, and its precursor substance is contained more in the tail end and near the skin. Thus, there are ways to deal with the pungency; advices about which part is suitable for what kind of dish are available almost everywhere. Now what I don’t know is whether the bitterness is caused by the same substance, isothiocyanate, or not. My hunch is probably “No,” because simmered daikon can be bitter without any pungency.

Then I have no idea if there is a way to avoid certain bitter parts in a daikon or tell bitter daikon from non-bitter ones. Harvest season or fertilizers used may make some daikon more bitter than others, but how can you check out such information when buying one at the store? So all I can say is, "To choose good daikon, choose fresh ones. And if worried about bitterness in simmered daikon dishes, don't skip the pre-boiling." That's about it. Sorry.

As for the softening effect, some say that an enzyme contained in rice bran makes daikon soft, though I couldn’t find any site clearly mentioning the name of the enzyme. But in my experience, daikon did soften quicker when a little amount of rice or rice-rinsing water was used for pre-boiling.

So, to me this pre-boiling technique is not a mere old-wives tale, but some of the seemingly scientific explanations seem pretty wishy-washy. That’s the way I see it. And I don’t really need to find out the ultimate truth of daikon boiling anyway. What’s more important for me is the feeling of warmth and happiness that a tasty winter dish brings to me…

... like THIS! :D

** Just in case:
After chopped daikon are "pre-boiled"with raw rice or in rice rinsing water, they need to be drained, rinsed with running water and then cooked in water and seasonings. You don't want to use the colloid solution from the pre-boiling for cooking and seasoning the daikon, of course.



Rei said...

Hi Obachan,
Your photos are really becoming exceptional.
I am continually inspired to attempt some version of your dish.
Thanks again Obachan!

K and S said...

looks delicious!

Unknown said...

Very enlightening. I learned something today. A little rice while cooking daikon makes sense now. Using just starches doesn't sound good (making glue), but rice is so easy. I bet turnips too would be nice to cook with a little rice then too?

Anonymous said...

I've always loved daikon.. :)

obachan said...

Thank you. Now I'm really enjoying shooting food photos. I mean, I always liked it, but now I feel much, much better about my photos. :)

K & S
BTW, you're bloghopping this late?

Thanks.I feel rewarded.
Yeah, some people do pre-boil turnips this way.(They say that turnips soften faster than daikon.)

Mama bok
I hated them when I was a child, but now it's changing. One daikon dish I still hate, though, is simmered daikon with squid.

K and S said...

he he I'm in Hawaii now, so it probably looks like it :)

Pinkity said...

Love how your pictures are looking so Martha steward-ish... I love Martha steward mags so I can proudly say I know what I'm talking about!!! xoxo

Anonymous said...

I agree with Rei and Pinkity-- your pictures are amazing. I always liked your photos but they are just getting better and better. You mentioned in an earlier post that you got some tips from a few how-to food photo sites, and I was wondering if you wouldn't mind sharing the links. I would love to be able to take pictures like that!

Oh, and thanks for all the daikon research! Interesting stuff.

Aliff Danial said...


Im desu. I just stopped by here and found that this website is interesting! I was in Japan for six years and now in Malaysia. The food is look nice. Could you please teach us how to make Udon no Dashi. In Malaysia, we only have soyu.

Im Danial

obachan said...

K & S
Woops. I haven't been to your site recently so I didn't know.
Have fun! :D

To be honest, I didn't know what her photos looked like. (Actually her name didn't draw my attention until she went to jail. :P)

The websites that really helped me recently are:
(All in Japanese)

The key is effectively blurring the background. ;)

Im Daniel
Yokoso Daniel-san,
Thanks for stopping by. I don't have a good udon dashi recipe, but I think I can google and pick a recipe for you sometime soon. Please give me a couple of days.

Anonymous said...

Hi Obachan,

Very informative. I'm going to try putting some rice when I cook Daikon next time. Wonderful tip! Thank you!

Rei said...

Obachan, hello!
Just a reminder for response to Daniel's request for Udon dashi. I use one from your region. An iriko dashi called, Sanuki dashi. With kombu, iriko and shitake mushrooms. It makes great miso soup too! But, if you have something else in mind please share it with me too. Always like to try something new (especially from you) Domo arigato gozaimasu.

obachan said...

Thanks, Kay and Rey.
Daniel, sorry about this late response, but for now, let me give you the recipe on this site.
The 6 cups dashi, 1/3 cup soy sauce, 2 Tbsp mirin and 1/2 tsp salt are the ingredients for the soup. And to find out how to make dashi, click on the "dashi soup stock" link in the PREPARATION.

To tell you the truth, this is not the udon soup that I'm familiar with. Like Rei said, in our region we use a little different type of ingredients for making dashi stock for udon and use light soy sauce for seasoning the soup. But probably the "different type of ingredients" would not make sense unless you actually see them in a photo, so I decided to post about it sometime soon (hopefully).
So if you're interested in the udon soup in our region, stay tuned! ;)