Not-so-sweet Tsubu-an: Japanese Azuki Bean Paste (revised and updated)

Sweet azuki beans

(Update posted January 2011:) I've updated this recipe for classic tsubu-an or "chunky" style sweet azuki bean paste, originally posted back in June 2006, once again. In March 2010 I added instructions for making it with a pressure cooker - the way I've been making tsubu-an for the last couple of years. Since this was originally posted, I've received a number of comments from people who had trouble with their beans getting soft enough. After some experimentation, I've found that if the beans are fresh you can just add the sugar while cooking without much trouble, but if the beans are a bit old - which is the case more often than not unfortunately - you may run into problems. So, in this latest edit, I've revised the instructions so that people having problems with the (possibly old) beans getting soft enough, will have more success.

A lot of Japanese sweets are based on beans that are cooked with a ton of sugar to a paste-like consistency. Red azuki (adzuki) beans are the most popular kind of beans to use in sweets, and sweet azuki bean paste is called an (餡) or azuki-an (小豆あん).

There are many kinds of azuki-an, but the two most commonly used types are koshi-an, and tsubu-an. Koshi-an is an a smooth paste made only from the inside parts of the bean combined with sugar. Tsubu-an (粒あん) is more rustic - the whole azuki beans are cooked until soft, then combined with sugar or sugar syrup; the beans are partially crushed or left whole. (Partially crushed an is also called tsubushi-an (つぶしあん) sometimes. Tsubu-an and Tsubushi-an may sound very similar, but they mean two different things - Tsubu-an means 'whole-bean' an, and Tsubushi-an means 'crushed' an.) (A third type of an that is often seen in commercial sweets, though rarely made at home, is ogura-an (小倉あん), which is koshi-an combined with whole, large "Dainagon" azuki beans cooked in sugar syrup.)

My late oba-chan (grandmother) used to make ohagi and botamochi with homemade tsubu-an every spring and fall. I hated commercial an as a child since it was usually sickly sweet, but I loved oba-chan's tsubu-an; it was not too sweet and even slightly salty.

This not-too-sweet tsubu-an is a good filling for steamed buns; these are called an-man. (I still don't like anman myself for some reason though.) It's also used for dorayaki, which is basically just two small American-style pancakes sandwiched together with a dollop of tsubu-an in the middle. Other Japanese foods that use tsubu-an include anpan (a sweetish bun) and taiyaki (a fish-shaped waffle with an in the middle) My favorite way to eat it though is just as-is, at room temperature. I even add a bit more salt to it, because I love that sweet-salty combination of tastes. (See the links at the bottom of this page for recipes on Just Hungry that use tsubu-an.)

Recipe: Tsubu-an (or Tsubushi-an)

  • 2 cups washed azuki beans
  • 3/4 to 1 cup sugar
  • 1/2 tsp sea salt

Conventional method

Soak the beans in cold water to cover for 24 hours.

Drain the beans and put them in a pot with water to cover. Bring the water to a boil, boil for a minute then drain the beans. Rinse the beans briefly under cold running water and drain again. Put the beans back in the pot with fresh cold water, bring to a boil, then drain and rinse again. This twice-boiling gets rid of much of the surface impurities and makes the an taste cleaner.

Put the beans back in the rinsed pot, and add enough water so that it comes up to about 2cm/1 inch above the beans. Bring to a boil, then lower the heat to a low simmer. Add water if it boils away. Skim off any scum on the surface. Cook until the beans are completely cooked and falling apart. Drain the beans, reserving the cooking liquid.

Put the pot of beans back on medium-low heat. Add the sugar and salt in 3-4 batches, while stirring with a wooden spoon or spatula to distribute the sugar and salt evenly. When the sugar melts, it will exude moisture, but if it seems a bit too dry or sticking to the pot, add a little of the reserved cooking liquid back in. Continue cooking while stirring occasiontaly, until the sugar is completely melted and absorbed into the beans. This step takes 10-15 minutes.

At this point the beans should be soft enough to mash easily with the side of your spatula. You can also use a potato masher. Turn out onto a plate to let cool.

Pressure cooker method

With a pressure cooker, there's no need to presoak the beans, though you can if you want to.

Put the beans in a pressure cooker, with enough water to come up to at least 1 inch / 2 cm above the surface of the beans. Bring to a boil, boil for a minute, then drain the beans. Put the beans back in the pot with fresh cold water, bring to a boil and drain again. This twice-boiling gets rid of much of the surface impurities and makes the an taste cleaner - particularly important when using a pressure cooker, since you can't open the lid while the beans are cooking!

Wash out the pressure cooker pot and add the beans back, with enough fresh cold water to come up to at least 1 inch / 2 cm above the surface of the beans. Put the lid on and lock. Bring the pressure cooker up to pressure over high heat, following the manufacturer's instructions, then lower the heat and cook for 20 to 25 minutes (15 minutes if the beans were pre-soaked). Let rest for 10 minutes, then remove the pressure so that you can open the lid safely. At the point the beans should be completely soft and falling apart. Drain off the cooking liquid.

Put the pot of beans back on medium-low heat. Add the sugar and salt in 3-4 batches, while stirring with a wooden spoon or spatula to distribute the sugar and salt evenly. When the sugar melts, it will exude moisture, but if it seems a bit too dry or sticking to the pot, add a little of the reserved cooking liquid back in. Continue cooking while stirring occasiontaly, until the sugar is completely melted and absorbed into the beans. This step takes 10-15 minutes.

At this point the beans should be soft enough to mash easily with the side of your spatula. You can also use a potato mssher. Turn out onto a plate to let cool.

Both methods - storing tsubu-an

Tsubu-an will keep in the refrigerator, well covered, for up to 3-4 days. It doesn't freeze that well - the texture turns rather grainy.

Notes and more links

  • See my article about Japanese red rice and beans for more about azuki beans.
  • I hate the word "adzuki". It sounds like some made-up word, probably coined by an non-Japanese speaker, and is phonetically incorrect. Let's stick with "azuki"!
  • You can find azuki beans at South Asian/Indian grocery stores, as well as Chinese grocery stores - though the ones you can get from Japanese grocery stores are of higher quality (and more expensive). You'll need to know what you are looking for though, since they are not marked as 'azuki/adzuki' but just as 'red beans'.
  • I used to have a paragraph here about old beans, but I believe that the revised method here should work even if you do have not-quite fresh beans. However, if you can please do try to find fresh beans, azuki or any other type - they are so much better!
  • While an may seem rather healthier than western style sweets since it's, well, beans, do remember that it also has tons of sugar! (See Wagashi are not some sort of Magic Japanese diet food)

Recipes on Just Hungry that use tsubu-an:

Filed under:  dessert japanese legumes vegan wagashi beans

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Comments

"The rest of my body hasn't been back to Japan in some time, but my belly insists on being fed food from home on a regular basis....And if I refuse to listen to its demands, it gets very cranky."

Boy, I can relate to that.

I love an-pan, and dorayaki. (Do you remember that cartoon An-Pan Man? It just sprang into my mind.) My mom's favorite dessert is to boil azuki in a light sugar syrup and then pour it over vanilla ice cream.

I don't think I've ever had a homemade version, but I love all kinds of red bean paste! People who haven't had it before are usually perplexed when I talk about a sweet mashed bean dessert. :) Maybe I'll use your recipe and then eat it by the spoonful.

Not too long ago we did the same thing: the less-sweet-than-customary ogura-an.

We used it to make an donuts.

It makes an-donuts a slightly respectable breakfast, instead of an indulgent afternoon snack.

The downside is the lower sugar content means it doesn't keep very long.

I am thrilled you posted this! I too feel the same way, my belly (or is it my tastebuds/tongue?) has a "home base."

I have a mind now to go buy some azuki beans and make some red bean paste! I have always preferred it to other western fillings like creme.

Yoko: I love Anpanpan and his whole family! Kogepan too!

Robyn and Christine please try it! It's really really good for people who like beany things.

Jason: an-donuts sounds interesting. Though I seem to have a slight problem with an when it's heated (probably why I am not fond of anman)...

A few years ago, whilst travelling in Japan we had the surprising experience of biting into what we thought was a jelly donut...turns out we were wrong. Nothing quite like expecting jam, but getting beans in the morning.

Sweet beans sound like really interesting stuff :)
I wonder though, approximately how long does it take to cook azuki?

Not longer than any other beans...or even shorter than say white beans (since they are smaller).

I recently tried what were called "peach buns" at a fair-to-middling Chinese buffet restaurant...these were steamed buns quite prettily made up to look like small white peaches. I recognized the filling almost instantly by texture when I sampled the bun, and was pleasantly surprised.

It was red-bean paste, lightly sweetened, and quite nice indeed, even if a bit plain. I make it a point now to put one or two on my dessert plate when I go to that restaurant.

Better yet, I'll learn to make them. We have a well stocked Chinese market here in town...

There was a Japanese convention in London last July. One of my favourite events was a stall demonstrating mochi pounding which then gave out free samples of the rice-dough wrapped around sweet azuki paste. I have found recipes for azuki paste and recipes for rice dough but nowhere that tells me how much of each i need to combine the two...
I don't have a rice cooker and I plan to make the dough with Shiratama-ko. Would i be able to make and boil the dumplings and then flatten them agin to fill with bean paste? or should I fill the uncooked dumplings with bean paste and then boil them?

Why do you need a recipe to tell you how much of each? Use your head and figure it out yourself. Make a bowl of dough and make some balls of azuki paste, then put them together. What's so hard? Do you think that if you use a little too much azuki paste, you'll die? You won't die, but you'll LEARN. You mix glut. rice flour with water and sugar/salt (again, figure out on your own how much to use) and microwave it in a bowl. Then wrap it around balls of azuki paste.

You would make the dough, wrap it around the an, then steam it ...or just eat as-is. I'll try to post more wagashi recipes soon...

Hi Maki, can this recipe be slightly altered to make red bean soup with toasted mochi...I think it's called zansai? Now that it's cold out, I always stock up on packaged, ready-to-eat zansai. But it's getting expensive, about $2.40/pack, and that is one serving. Another reason I'm asking is because I have tried different brands, and some were way too sweet. I want to make it myself so I can control the sweetness. Thank you!

Sure, you can thin this out with hot water to make the zenzai soup base You may have to adjust the salt/sugar a bit after adding the water.

I read some other food blog a while ago and the (Asian) author described her need to have rice and other Asian foods as "Asian Mouth Disease"!! I had a good laugh at that, as will anyone of Asian origin who craves rice and noodles after just a few days or shock horror even a week! I can't do without my rice and noodles for long. Bread, pasta and potatoes just don't make the cut! I'll have to try out some an-recipes soon!

Do you ever find that before the beans get to the mushy stage they go funny and really hard? I think I must be doing something wrong! :S

I nearly fainted when I saw this. I LOVE RED BEAN PASTE. I could eat it all day long... haha although I don't in case I become diabetic from all the sugar.

Thank you for posting this. :-)

I was wondering if the spelling "adzuki" might make a little sense - at least originally. This is coming from someone who knows next to nothing about Japanese; but I thought that while nowadays the sound "zu" is almost always represented in hiragana by ず, in the past it was arbitrarily written づ in some words, and that consequently in one system of romanization, "zu" was used to represent the hiragana ず, and "dzu" for the hiragana づ - though both were to be pronounced "zu". But very likely I don't know what I'm talking about; if so, don't feel bad saying as much.

I believe that's correct, although I'd have to get hold of an old dictionary or similar to say for sure. The English spellings "adzuki" and "aduki" (awful, but I've seen it!) suggest that the old spelling was あづき. For that matter, the old pronunciation might have been this way too; modern Japanese "z" often corresponds to "dz" in older stages of the language (and in some modern dialects: compare Nagoya "midzu" to standard "mizu").

OMG thank you so much for the recipe. I've tried really hard to find a goo red bean paste recipe and this is the first one that I've really liked. (After I was done filling some manjuu with it, my mom ate all of the leftover azuki!)

And, like mashed potatos, it looked a little dry to me so (I didn't add a lot of sugar in the beginning) I added some maple syrup. It was totally yummers.

Maple syrup is a great addition to an!

Hopefully either my local (and only) Japanese supermarket will begin to sell red beans. I can never find them, only in premade Japanese goods. Thank you for the recipe however, maybe someday I will be able to.

I wonder if this sweet bean paste would be good inside rice balls. Then again, I can eat nearly any two things together in the world!!

Hello,

I'm going to make Daifuku, pretty soon. I'm wondering on the anko part, is it possible for me to use Ogura instead?

I'm pretty confused about Ogura, could you tell me more on it? Thanks.

Hannah

Ogura-an is sarashi-an (filtered smooth an) into which large azuki beans, called Dainagon, which are cooked separately in sugar syrup, are mixed in. You can use it for daifuku, sure.

I have had good luck in the "bulk food" section of local produce and more stores, as well as "natural" supermarkets, such as Whole Foods or Wild Oats.

I followed your recipe and made two batches of tsubu-an today! The second batch was great, but the first batch was not that solid (probably because I left too much water in it) and was a bit too salty, so it tasted sort of horrible. I don't want to throw it away and waste it though, is there any way to fix it? Should I add some more water to it to make zenzai?

Thank you!

Hmm, counteracting the saltiness may be difficult if you put in too much salt. You may want to try making some sugar syrup (dissolving sugar in water, say 1/2 cup sugar to 1 cup water) and adding that to the beans and heating it through.

I can't tolerate sugar anymore so commercial an paste is no longer an option for me. I tried the recipe with 1 cup of Splenda and it turned out pretty good! (I did run the batch through a sieve though, since I prefer the smoother paste.)

I'll probably try it with other sweeteners and see which is the most authentic tasting--the Splenda version was good but I want to see if another SF version can more closely resemble the original.

Just wanted to say thank you for the recipe! ^^

Good to know it does work with an artificial sweetener. I wasn't sure if there would be enough substance to the beans. Thanks for the report :)

I am going to try using agave nectar... Maybe that would work for you?

hi,

just a simple and inexperienced question, but what kind of sugar do you use? White? Brown/yellow?

thanks, arigatou (sorry spelling)

I use white sugar. (never seen yellow sugar...)

hi, thanks for the reply ^^

maybe it's not common outside where i live, it's like a more raw sugar i guess, something like brown sugar

ah ok...I guess I see raw sugar as being light brown, not yellow ^_^

I followed your recipe, but my bean paste turned out more of a white-ish color. Is that normal? Or is there something that I may have done wrong?

I was wondering, if the an were stuffed into onigiri and then frozen for bento - would the paste hold up? Or would I need to make the onigiri each morning?

Hi Maki!

When cooking the beans, I found a similar situation to one posted in an comment above: the beans skin is nice and intact and they went funny - like dehydrated- - at one point. I added more water and kept cooking at they are still not mushy. it's been over two hours of simmering, only 1.5 cups of beans. Where did I go wrong?????

thank ou!

-M.K.-

A couple of reasons that I can think of for this happening, any or all or none of which may apply, are, 1. the beans were rather old to begin with, 2. the beans were not soaked long enough. If you did soak them for 24 hours, and cooked them for 2-3 hours and they are still hard when you take one between your finger and thumb and try to smush it, then there is something wrong with the beans to start with...try with another batch.

(Note that this article was written more than 4 years ago, and since then I've switched to using a pressure cooker to cook my azuki and other beans.)

[quote=maki](Note that this article was written more than 4 years ago, and since then I've switched to using a pressure cooker to cook my azuki and other beans.)[/quote]

Hi, I cook all my beans in a pressure cooker, too. I want to make this recipe, but can you tell me please how you adapt it to a pressure cooker? It doesn't seem right to put the sugar in the cooker. Do I mash the sugar into the beans AFTER they're cooked? Please let me know!

Thanks, and I'm so excited about your site! The pork buns are wonderful and I'm joining a friend tonight to try a vegetarian version. All the best...

I like to cook beans from dry, and of all the beans I cook, azuki beans are the ones most likely to not soften all the way. And it's usually only about 10-20% of the beans that don't soften.
I had this problem with other beans bought at the grocery store and tried all the advice about softening beans, like not cooking them with acid ingredients. But it still happened.

Finally I found it was as Maki said, they were too old. Beans at the grocery here in the USA can be 2 or more years old when you buy them and they just won't cook up soft anymore. Now I buy beans from specialty outlets on line who's beans are really fresh, like Rancho Gordo Beans.

Unfortunately, they don't carry Azuki beans! And so far I can't find a good source of fresh dried Azuki beans. I really love Anko and since I also think the store bought kind is way too sweet I make it at home. But it's so frustrating to get those gritty half-cooked ones in it.

Asian groceries haven't worked out either, as I've tried all 5 of the ones near me, and their beans are old too. There seems to be only about 3 brands imported, I think all are from China.

Does anyone know a good source for really fresh Azuki dried beans in the USA?

Bob's Red Mill, which is available on Amazon.com, may be worth a shot - they have a good reputation in the alternative-grains area so their beans are probably good too (though I have not tried them myself).

Ah! Good idea! They do have a good rep, I'll check and see if they have Azuki beans. Thanks!!

Thank you so much for all your wonderful recipes!
I make also sweet black bean paste, in a similar way. I fully cook in water 1# beans at a time, freeze some (drained, no sugar/salt added) and use the rest to continue cooking with sugar and make into a paste.
The frozen beans help cut down on cooking time for the next time I want a paste.
It works well for me :)

I know what you mean about "adzuki." Sounds lige subones node id stubbed ub.

IM a fan of Red Bean Paste so I know what im going to make this weekend.

Thanks for sharing this Maki.

Does anybody know what exactly is ogura-an, I have read this are yude azuki mixed with koshi-an?
Few tips:
It is better for tsubu-an to use azuki which are light in color, they dont have such tough skins.
If you have dark azuki, it helps to add some baking soda in the soaking water.
Maybe you are interested in this tsubu-an recipe:
http://wagashi-net.de/blog/wagashimaniac/2010/03/anko-recipe/
There is also a recipe for koshi-an(sorry,not translated yet) and shiro-an(translated).Sugar amout can be reduced, of course.
I have the same problem, to get fresh beans in Germany, I always do long soaking, in summer in refrigerator.

I have added in some correct information about ogura-an in the article (I had it wrong!) Original ogura-an is indeed koshi an mixed with a specific kind of azuki beans (Dainagon) that have been cooked in syrup.

I have to disagree about the light colored beans being 'better'. The best Japanese azuki beans, such as Dainagon, are actually quite dark and shiny. But they are also expensive... well the best ingredients are always rather expensive I guess.

I love azuki paste in all forms. It's just so versatile. I love the photo as well!

I am new to ur blog. I am very curious about Japanese cooking and BTW I am an Indian. I will try to prepare some dishes by following ur recipes. I blog about Indian recipes. Do drop in when you have time. Thank you :)

Maki, I meant azuki which are really dark(sorry, my English again), these are much darker than hokkaido or dainagon azuki, which have a intensive red colour.
Here in Germany we have few azuki in organic quality, all very dark red, almost purple(no shine) and these aren't good - very firm skins, also the taste of finished tsubu-an is "strange".
The best azuki I can get are hokkaido and these are expensive.Right now I`m testing all azuki which are available and this is really true, the "lighter" ones are better.
I will make pictures from the tested azuki, there are big differences in colour.
Of course are hokkaido/dainagon the best!
Thank you about ogura-an, I wasn't sure at all and couldn't remember where I have read about it.

Hi Maki, I'm planning on making this in the next day or two after having a bit of a craving for dorayaki lately, but there's just one quick question I wanted to ask: When you say 2 cups of beans, is that 2 cups before or after soaking? I'm guessing it's before judging by the order it's written?

Actually ignore that, I just soaked 2 cups of dried beans overnight and I could probably live off it for a week, so yeah... 2 cups of soaked beans!

Hi Maki,

I just made a batch of tsubu-an and after tasting a spoonful of it, I realized it has a slight bitter aftertaste. I've eaten Chinese style of red bean soup which have this similar bitter aftertaste.

So I was wondering if you know of any method to remove this bitterness in tsubu-an besides adding tons of sugar.

Did you follow the procedure of bringing the beans to a boil, draining away the water and rinsing the beans and starting over? The preboiling/draining/rinsing should get rid of the bitter taste. If the beans you have are still bitter, try repeating the boiling/rinsing procedure before going on to cook the beans.

I think it might be my stove, but I've noticed that every An recipe I've tried has always taken significantly longer than what is actually written on the website.
This recipe turned out great. Not too sweet.

I'm just wondering if I'm the only one that has this problem? Even using a pressure cooker to cook the beans, it still takes me 2 and a half to 4 hours to get past a very liquid consistency into anything remotely paste-like.

Do you have any tips to compensate for this?

Has anyone made these in a slow cooker? Any tips? Would it work?

Thanks for the recipe. I followed exactly the recipe but after more 3 hours of cooking I gave up. the bean still not very soft as it should be. According to the traditional way of cooking all kinds of bean, suger should never been added to the pot until the bean already soften.

You must have read my mind, because I have been working on a revised version of the recipe, which is up now. With old beans,it's better to cook the beans before adding the sugar. With fresh beans this isn't a problem, but since beans don't get 'bad' a lot of grocery stores tend to carry older beans. (Note: I usually have fresh beans from Japan to deal with, which is why I didn't find this out until I did some tests!)

it's so funny you're posting this now - right in time to make the red bean mochi cake (new year's cake) for chinese new year!

love both your blogs & i wish i could have been in either seattle or new york for your book signings!

This looks super easy. I am wondering if you could use honey instead of the sugar?

I wouldn't really recommend using honey. Honey has a distinctive flavor for one thing, which may change the character of the an. Also, you need quite a lot and at the moment honey is expensive!

We tried making daifuku for Christmas, but I did something wrong with the an. The beans cooked nice and soft, and it tasted just like we remember, but it was really liquidy, like the consistency of chili. We didn't add any water, just the mashed beans and sugar. Any ideas of what went wrong? Actually, I just realized that the recipe we used involved mashing the beans, then adding the sugar and cooking again, should we add the sugar, then mash, or does that not matter? Our mochi buns were very squishy, but they tasted good! We made some ichigo daifuku too.

After you drain the brothy water to mix in the sugar and salt, can you drink that water? Are there any beany nutrients in it? :D

I've just discovered my love for azuki bean paste. Maybe this is the only way I'll ever like beans - at least it's the best. :D

I have seen two recipes for bean paste, one is this recipe and the other is in a book I have. The difference between the two is this one says to wash the beans beforehand, and the other doesn't say anything about pre-washing. Is pre-washing a necessary step?

You should wash and sort beans, taking out bits of stone, dirt, grass, etc. if needed. If you grow your own, or buy the beans from a place that doesn't do the sorting and so on beforehand. If the beans are nice and clean, there's little need to wash them.

Hello Maki

First of all, this is my first time posting. I've "lurked" on your wonderful site (and JustBento) for several years now, and tried many of your recipes, which all came out great, but this particular one is so outstanding, it just forced me to come out and thank you.

The results were PERFECT. Absolutely flawless, with a light, delicious paste with amazing texture that is better than anything I've ever purchased in grocery stores.
The azuki beans we get here in Brazil are quite smallish, shirvelled affairs, so the pre-boiling and vigorous pressure-cooking are great to really cook them through and pry the flavor and natural sweetness form them.
The whole thing, from start to finish, took less than an hour and a half (and that's because I'm a very slow cook!).

Thanks again and get well soon!

Greetings from Brazil!

Hello,

Just a quick question, does it matter if I use brown sugar to sweeten the azuki?

Thank you for the recipe!

Brown sugar will add the flavor of, well, brown sugar ^_^ to the beans, but if you don't mind that that should be fine.

I used this to make the filling for some an pan this afternoon, it came out amazingly well for a first try!

FACT: Chickens love red bean paste.

do you know what kind of asuki bean paste is used in commercially produced ice cream? is it chunky, smooth, really sweet, not so sweet?

Hey! I wanted to thank you for sharing this recipe as I tried it (with pinto beans since that's what I had on hand) and am really enjoying it. What a great side dish for a bento mixed with rice! It has a nice savory/sweet flavor that compliments many different main bento dishes! This recipe is definitely entering the 'keeper' box. :D

Hi. I have a question. I am trying to make the red bean paste for mochi. I soaked the red beans for 24 hours and then proceeded to drain them and bring them to a boil. I then took them out of the pot and again drained them and returned the to the pot and placed them on low heat to simmer. I returned after an hour and they were still hard so I added water and returned after about another hour and they're STILL hard.

What's wrong :(

I'm wondering if red bean paste can be canned like jelly, apple butter, or veggies?

Maybe if you could provide commercial canning levels of sterility and vacuum packing...but I have never tried it so I can't say for sure. I am doubtful though.

What is the différence between anko and tsubu-an please ?
I search everywhere and I don't really know . Could you please help me ?
See you **

I love an, but am diabetic and must limit my sugar intake. Have you ever tried one of the sugar substitutes, such as truvia or splenda?