The more I read about yeast and fermentation, the more conflicting, confusing (and possibly incorrect) statements I come across. I have read in several bits of literature that yeast requires oxygen for biosynthesis (i.e. cell growth) and prefers to use it for this purpose, to which end it absorbs oxygen shortly after pitching (i.e. during the lag phase and before fermentation begins). Many sources indicate that almost all the dissolved oxygen is absorbed by the yeast within 30-180 minutes after …
The specs for Lallemand BRY-97 dry yeast explain that aeration of the wort is not necessary. I've had good results following their instructions precisely, but I wonder if I'm missing out. I wonder if they are saying "technically you don't need to aerate". ...in other words, do I need to buy aerating equipment? From the technical sheet, at the end of the REHYDRATION section: BRY-97 yeast has been conditioned to survive rehydration. The yeast contains an adequate reservoir of carbohydrates …
This is my first shot at homebrewing, using Northern Brewer's American Wheat Beer kit which is based on liquid malt extract, Willamette and Cascade hops, and a packet of dry yeast. I brewed and put the hopped wort into fermentation on Friday. By Sunday morning (~40 hours later), fermentation seemed to be moving along at a good clip -- I could see bubbles traveling through the airlock about once every 2 seconds. However, by Monday morning, bubbling had completely stopped. …
It's time for some summer brewing and that means the warm tap water running through my wort chiller will have trouble cooling my wort down below the upper 70s. Even for the Belgian style beer I'm brewing this would be too high of a pitching temperature per the recommendations.1 Based on related posts here, I am comfortable throwing my brew pale in my kegerator for a number of hours to cool prior to pitching because of the following: I am …
I purchased a Tetra 77848 and some standard 1/4" ID tubing to aerate my wort. However, there's an issue with the tubing hooking up to the output on the tetra, it's too narrow for the 1/4" tubing. I rigged the tetra by wrapping it with some electrical tape to make it thicker, but it tends to come pop off while I'm aerating. Is there a good way to attach this tubing to the air pump?
I have been "stacking" batches and have attenuation issues. I will brew 5 G today and pitch the yeast. I repeat these steps tomorrow and add it to the top of the first batch, although I do not pitch more yeast. I also do not aerate either batch. I believe I need to aerate, but am unsure when to do it; 1st batch, 2nd batch, both batches. Also, should I pitch on the 2nd batch as well as the 1st? …
Currently studying for the General Certificate in Brewing from the IBD. The section on wort oxygenation/aeration states that a disadvantage of in-line cold wort aeration is the need to increase solubility by injecting small bubbles or ensuring vigorous mixing and injecting when wort pressure is high Wouldn't the relatively cool temperature of the wort actually increase the solubility of the oxygen, and so reduce the need for vigorous mixing? Or is this actually a reference to the aeration taking place …
I'm planning on brewing my first batch of beer soon, but I will have to do the cooking part at my parents house, which is an hour drive away, and then ferment the beer at my apartment. At what stage in the process should I transport the wort? Before or after pitching yeast? And how long after I cool down the wort can I still pitch the yeast? I've read that the wort should be aerated before pitching yeast anyways, …
I'm a bit confused about this. In my own experience, I'm no longer experiencing acetaldehyde flavours in my beer after improving my aeration methods and at the same time starting to use yeast nutrient. In his IPA book, Mitch Steele says that the biggest cause by far of acetaldehyde comes from dying yeast cells from which acetaldehyde escapes. It's also stated that acetaldehyde production increases with yeast cell growth - so aeration will increase acetaldehyde production. I only use a …
When I bottle, I follow the typical step of boiling some water, adding bottling sugar, letting it cool, and adding it to the beer that's done fermenting (but still of course has live yeast floating around). Those little beasties probably would like a sip of O2 to grow better and carbonate the bottle better/faster, but I'm as careful not to add oxygen to the priming solution as I am to keep oxygen out of the beer. But I got to …
I'm very interested in ferment in corny-kegs after reading some questions about that here on this stackexchange. I will try it next batch, but there is a question about aeration/no chilling method: Normally I aerate my wort by splashing it when transfering from my no chill vessels to my fermentors, so I understand that I am mixing my wort to the air and all the microorganisms around when I'm doing that. Before splash I put my yeast in the bottom …
Do you notice any benefits in flavour or yeast activity over a regular air pump? By not blowing dirty air through your wort, could it keep down infections/contamination? Does pumping regular air through wort increase risks of infections/contamination? Useful Pages Oxygen Dissolved In Wort Shaking - 4ppm Air + Air Stone - 8ppm Oxygen + Air Stone - 14ppm
I extract brew, and the kits I buy from NB tell me to add cold water to the wort to get a total of 5 gallons, and then aerate before adding the yeast. However, if I do this I will always have more than 5 gallons of total solvent after pouring the yeast in, unless I try to add an amount of water less to the carboy equal to the volume of the yeast. It would be easier for me …
I have two yeast starters going on my two homemade stir plates. The stir bar or the stir plate for one of them is malfunctioning and I can not increase the speed enough to get a vortex going. It is simply keeping the yeast in suspension. On the first yeast starter I ever did, I would put an aeration stone in the flask every 5 hours, in addition to the oxygen obtained through the vortex of the stir plate. I …
I've read online that the size of the vortex in a yeast starter does not matter. Why is this true? When I was experimenting with water yesterday, I created a monster vortex (very cool) and could see air bubbles screaming all over the water; turning the vortex down into a baby vortex resulted in no air bubbles screaming all over. Some people say that the point of the vortex is just to keep the yeast in suspension which will make …
How much oxygen do I need to put into my wort? I've heard that homebrewers need to aerate with an oxygen stone and either aquarium pumps or oxygen. Is this true, or is shaking my carboy enough to get proper oxygenation? How much oxygen is needed? Does it vary based on the wort? How effective are the various methods?
I had thought that the point of using a siphon when moving wort/beer is to prevent agitation and aeration and a ruined beer. So we use the siphon when moving cooled wort to the carboy for fermentation, when moving the fermented beer to the secondary fermenter and then lastly when moving the beer to the bottling bucket. However, I recently talked to another homebrewer who would strive for maximum agitation when pitching their yeast so the yeast is really integrated. …
When transferring from the mash tun to the brew pot, I had set the mash tun about 3 feet above the brew pot and let the wort flow out and fall to the pot. This caused a large amount of bubbles that stayed around until the wort started to boil. It does not seem like it would effect the beer in any way, but the more I thought about it the more I wondered. Does aerating the wort from transferring …