rice and amylase

[rottenpotato]

Ok, I have seen several posts here that relate to this, but I still feel like I have been unable to resolve this problem. I recently found some amylase enzyme at my LHBS and I got excited, because I have been interested in experimenting with other grains, specifically rice. I understand that making sake requires the use of a fungus called koji, and that to use rice as an adjunct it either needs to be gelatanized or flaked. At this point I am not looking to make a traditional sake, but just to play with an all rice brew of some sort using the amylase. I did a little experiment a couple weeks back with disappointing results.

First, I cooked about 2 cups of sticky rice, just as if I were to eat it normally. When it was fully cooked I did a mini mash, adding water and amylase, keeping it in the range of 145 to 150 for about an hour. I expected to find that the amylase had converted the starch in the rice into sugars just like a regular mash, and that it would taste very sweet at the end. Unfortunately it just tasted like rice soup. What did I do wrong? Is the amylase I purchased not sufficient to convert rice starch into sugars? My understanding is that it should be able to convert any starch. Am I missing something? Has anyone else tried this experiment with different results? I have seen posts about people using rice as an adjunct successfully, just adding cooked rice to the mash. How did you know you had successful conversion?

any advice would be helpful. Thanks!

 

[JRems]

If I use rice as an adjunct I use minute rice in the mash, you don't need to cook it first. I don't know about the amalaze enzyme, I don't have a problem with it converting when it's in the mash.

 

[Rip]

...try a much longer mash time maybe?

Conversion is dependent upon:
Appropriate Enzymes
Mash pH
Available starches
Time / Temp
(*beer gnomes optional)

Do a Google search and check out some instructions for making Amazake... (kinda the first step in making Sake).

You'll notice that folks are 'mashing' their amazake for 12-18 hours at ~140F. I think this might be because the cooked rice has to physically break down or such.
I've made amazake a few times now and have noticed that the mash isn't even sweet until at least 3-4 hours after mixing everything together.

It seems that barley is quicker to convert, maybe it's able to release starches more easily? Whereas the rice seems to be broken down from the outside and dissolved into solution as the conversion progresses (not too scientific I know). Minute Rice might work differently because it's been pre-gelatinized or processed or something. I haven't tried it yet since I hate eating that crap and don't have any lying around.

There could be some other minor issues involved based on the actual type or source of enzymes you're using... I think some of the fungi-derived enzymes may have a different pH range for effective conversion. If the long mash doesn't help, I'd start looking at mash pH then.

- M

p.s. Note that in the production of Sake, the Koji/Rice additions don't quickly convert to sugars... it's actually a very lengthy process that takes a few days. It's not at all like beer, where the mash is performed in one fell swoop at the beginning of the brew process!

 

[The_Professor]

...but I still feel like I have been unable to resolve this problem. I recently found some amylase enzyme at my LHBS ... I have been interested in experimenting with other grains, specifically rice. I understand that making sake requires the use of a fungus called koji, and that to use rice as an adjunct it either needs to be gelatanized or flaked. At this point I am not looking to make a traditional sake, but just to play with an all rice brew of some sort using the amylase...

Why not start with a small batch (1 or 2 gallons) using flaked rice and the amylase enzyme.
What yeast do you plan to use, what other additions?

 

[rottenpotato]

Thanks to all for the input. I'm trying to avoid using minute rice or flaked rice, mostly due to the pretension that I could use a non processed whole food product to create a fermentable. I hadn't thought of making amazake, many of the rice wine/sake recipes I have been able to find online seem to recommend using just steamed rice and a specialty yeast/mold combo that I haven't been able to get my hands on. Rip, I think you may have a point about the timing. What info I have been able to gather seems to imply that most traditional Asian recipes for rice wine involve what is essentially a really long mash, achieved by leaving a vessel out in the tropical heat for several days. Maybe thats whats needed for conversion, but then I am seeing brewers on this site recommending putting cooked rice in their mash which gave me hope of a simpler, more immediate effect. Maybe those brewers are just fooling themselves that the rice is adding anything, and all the sugars they are getting are just from their malts? I guess I will have to keep experimenting. Part of me hoped that someone with a stronger background in chemistry than me would be able to explain my folly and point me in the right direction.

 

[rottenpotato]

oh, and as far as yeast and other additions: I figured a dry wine yeast would be appropriate, maybe champagne yeast, which is what I use for ciders and fruit wines (and I have a lot of it sitting around). For my first batch I want to keep it simple, this is mostly about understanding rice as a fermentable, so I wasnt really planning adding much else. Maybe I should think about some lemon juice to help adjust the ph or some raisins for the tannins. Alternatively I think I have some wine tannins laying around I could add.

 

[Erichaskell]

Cook brown rice 16 min lowest heat, let sit covered one hour. Stir and add additional purified h20 to mush/loose consistency. Immersion blend. Add amylase (minimum amount under research) Stir thoroughly. Heat to 135 degrees F for one hour, 145 degrees one hour, 155 degrees one hour and 160 degrees one hour. Let sit until room temperature. Iodine test indicates no starch. I will determine best temperature, least amount of amylase etc soon but am thrilled to get the bullet near the center of the target.