Coopers Yeast Question

[chiguy]

I'm working on my second batch of brew, using Coopers Australian Bitter and their light malt extract.

My concern is the fermentation temperature recommendations. The instructions that came with the product say to ferment between 21-27C/69-80F, and that while it CAN go as low as 13C/55F (and as high as 40C/104F!!!!!!) they go on to say that deviation from the 21-27C/69-80F range will potentially introduce "spoilage", which I assume to mean unanticipated flavors.

Meanwhile, Google searches on this very topic have led me to believe that 68F should be the TOP of the range for brewing this kit, and that it begins producing diacetyl at that point:
https://www.homebrewtalk.com/f12/praise-coopers-yeast-92100/

So which is it? Is the Coopers yeast heat tolerant enough to produce an Australian bitter at temperatures in the 69-80F range? Or are the instructions bunk?

NOTE: I've tasted a modern Australian bitter before, which is a bit like a slightly more bitter version of an American macro lager. There shouldn't be much diacetyl/"butterscotch" flavor. The temps recommended do seem at odds with typical recipes for similar styles.

NOTE #2: My previous batch was a Coopers stout, with what I believe was the same yeast type, and fermentation stalled when I let the temperatures drop to the low 60s...though temperature may not have been the driving factor...

 

[BamaRooster]

I am not going to get into what should or should not be done. If it were me, I would ferment below 68 degrees. I usually shoot for between 64 and 66 depending on the cold tolerance of the yeast being used.

 

[unionrdr]

Midwest says the yeast is good between 62-72F. So far,67-68F has been good. Even at 74F,it doesn't produce diecytl. It has to go higher than that to get that result,ime. What results at 70F on up is a bit of nondescript fruity esters on the back. Not what I'd consider an "off flavor" though. Temps below 70F give a lot less of this ester.
I found that Midwest & Northern Brewer carry the 15g packets of the same Cooper's ale yeast as in the 7g packet in their cans false lid. I'll be trying the 15g packet in a couple of our average gravity pale ales maybe this wekend. I believe the 15g packet would also be fresher from Midwest. And give faster/better results. Love it or hate it,I think it's a good yeast for aberage gravity work with good temps. I got it to work in ales up to 1.065OG thus far.

 

[chiguy]

Excellent. Thanks for the input fellas. My basement is in the 65-69 range depending on location. Sounds like I should be ok. At this stage of my (in)experience, as long as the final product is drinkable, I'm happy.

unionrdr, regarding the Cooper's yeast, I'm starting to wonder if the yeast included with the cans is the same as that sold separately or not. 62-72F definitely is at odds with what their instructions say. I'm wondering if maybe they condone higher temps with their instructions in order to speed up the fermentation process for the less patient?

 

[aidan]

My approach with Coopers yeast is to shoot for around 20C +/- 2. I think the instructions are as you said 'bunk'. My guess as to why they specify the higher range is due to the short ferment time that they state. i.e. if you go below 21C it will probably take a bit longer to ferment. Kit instructions are all about quick & easy. I don't mind taking a bit more time for better results.

 

[unionrdr]

What they mean is that higher temps,it'll still make drinkable beer,but with less diecytl than you'd get otherwise. But damn that BS! Just keep the temp between 65-68,& the results will be pretty damn good. I also re-hydrate dry yeast.
Their dry ale yeast is the same in the 7g packets in the can's false lid as the 7g & 15g packets purchased seperately. I have 2 of the 15g packets from Midwest delivered yesterday in the fridge now. I'll be try those re-hydrated in 2 pale ales we'll be brewing this weekend if the LME cans from Amazon get here on schedule. It'll be an interesting experiment with 2 of our recipes of pale ales being brewed the same as last time with the only difference being the larger yeast packet. And hopefully fresher as well.
** By the way,I gave the yeast a sniff last time,& it had a white grape sort of aroma...interesting.

 

[chiguy]

Wow. Awesome info. Glad I registered.:rockin:

 

[Beer30Dave]

wow. Awesome info. Glad i registered.:rockin:

+1!