Trying to kill off residual yeasts when mulling cider

[Glenn C Keller]

When I mull hard cider, spices are placed in a paint sock or cheesecloth and I heat the cider to 155 deg F. This speeds up the infusion process (keep tasting it for if the spices sit too long, the resultant product is way too bitter to drink). I add brown sugar instead of one of the many non-fermantable sugars to back sweeten. Usually comes out real tasty and it can be drunk over ice or heated. Problem I'm trying to solve , though, is figuring out how high to heat the cider to kill off any yeasts. I'm staying below 172 deg F as this is when the alcohol boils off (once the mixture reaches 172, how quickly does the alcohol boil off?). I thought that around 160 deg F would do it but the cider is still bubbling. Cold crashing may be another option but how cold? Any words of experience, please?

 

[CKuhns]

See this from @Chalkyt - He describes the pasteurization process in much more detail than I ever could. (Search for similar threads from him as there are a few more out there on the forum.

My pretty low tech technique is to bottle after clarifying and adding sugars to sweeten and immediately immerse them in the 160 Deg F water F for 10 minutes. (Have done a number of ciders and meads this way and never had a problem with yeast staying active.)

https://www.homebrewtalk.com/threads/heat-pasteurizing-and-carbonation-more-stuff.684883/

 

[Rick Stephens]

If your cider is holding over 140ƒ for very long you will have performed a very effective yeast kill.

 

[Glenn C Keller]

Thanks for the help here! much appreciated. I will read up on pasteurization threads.

I hadn't bottled the cider - it was in a 5 gal stainless steel pot and heated on the stove. It took around an hour to get the right spiced flavor and then I turned off the heat and let it cool which took another couple of hours. I temporarily place the finished mulled cider product into sanitized 1 gal glass bottles and left them in the kitchen where it was warm. When I opened up one of them, I heard some outgassing and bubbling forming so I placed them outside and left the bottle caps slightly loose. I was surprised that there were still some active yeasts as the temperature was above 140F for a couple hours.

 

[Rick Stephens]

Yeasties are dead with over a 140F for a couple hours. Residual dissolved carbon dioxide maybe?

 

[CKuhns]

hmmm... I suspect the "off-gassing" you heard had more to do with the change in temperature and associated slight change in volume in a sealed container vs. yeast eating more sugars. Could be residual CO2 off Gassing as @Rick Stephens suggests but after heating in an open vessel I wouldn't expect there to be any left and certainly wouldn't expect yeast to still be active. (Could be either one but I would think pretty unlikely)

Seal them up and Check it again every few days. I do check my ciders that are not pasteurized and waiting to be kegged in gallon jugs periodically and do find a few that off gas a little. But I attribute that to not pasteurizing.

 

[Chalkyt]

Have a look at a post by Jaypkk (3 December). There is a link to some recent work out of Washington State Universtity Which indicates that 60C/140F for a very short time will stop the yeast. Conservatively something between 60C/140F and 65C/149F for less than10 minutes should do the job for you as suggested by others above, and keep your cider well below the alcohol boiling point.

 

[Glenn C Keller]

Yes, perhaps a temperature change and restricted volume might be the cause of the bubbling. Only the full glass gallon jug exhibited the errant behavior. I split up the cider into two gallon jugs, each now about 3/4 of the way full and placed them outside with the caps slightly ajar (I'm in upstate NY). Haven't noticed any more bubbling and the chilled beverage is quite drinkable. I'll keep checking... thanks.