FERMENTING!
If you are not of legal drinking age in your country of residence then you are not allowed to visit this site. You are trespassing and are not allowed to read even one word after this paragraph. Not one word you understand? I said, not one word... Now if you're too darned young to read this, go to your room and have a 10 minute time-out.
G'wan now... Scoot! I'm watching you! 
:)
Now back to the show:
First off, I'm looking for a 10 or 15 gallon Corny keg. If you have or know of an extra one please email me. Thanks
Yeast! What a wonderful pleasure. While enzymes convert starches to sugars, Yeast converts sugars to alcohol and this is the cornerstone of brewing as we know it. There are many kinds of yeasts in the world but as brewers we usually use different varieties of yeasts of the genus Saccaromyces Cerivisae or Saccaromyces Uvarum. In short, Beer and bread yeast. There are several companies providing very specific yeasts to brewers. Yeast as much if not more than any other factor helps form a taste characteristic of the beer you make. The by-products of their respiration is CO2, Alcohol and by-products. These by-products impart a characteristic taste to the beer and without them beer would be relatively tasteless. At the least without these by-products beer would not taste anything like we know it.
Speaking of yeast and going back to sugars; there are several types of sugars and yeasts are very picky about which sugar they will eat. Yeasts are different and certain varieties ( called strains ) create expected flavors when they eat sugars and these flavors greatly affect the taste of the beer. There are companies that supply yeast and what they do is isolate a particular strain of yeast, give it a name and then farm that colony of yeast into small batches and sell them on slants of sweet seaweed jell called Agar, in liquid form or in dry packets. The yeast isn't actively eating and reproducing when you get it commercially, rather it's in a dormant state sort of like sleeping and waiting for sugar to come by. Depending on how the yeast is provided to the consumer, various steps are taken to activate the yeast but once they are in a yeast friendly environment they become active shortly after. In a single package of yeast one can expect to find between 45 to 60 billion hungry yeast cells waiting to pick on the bones of any luckless sugar they encounter. Many of these varieties of yeast are proprietary and there are several popular competing companies making yeast for home brewers. Most commercial brewing companies have their own "resident" strain of yeast nurtured by a in-house microbiologist so their beer will taste consistent from one batch to the next & one year to the next. The brewer selects the proper yeast strain from a yeast supplier to add to the flavor of the beer they are creating. Certain beer styles demand a certain yeast be used and the temperature that yeast must work in because temperature affects the way a yeast produces flavors and the rate of fermentation.
In a single package of yeast one can expect to find between 45 to 60 billion hungry yeast cells waiting to pick on the bones of any luckless sugar they encounter.
Some people "harvest" yeast from bottles of beer that contain sediment and haven't been pasteurized along the way. Sometimes this has wonderful results but sometimes there's a small bit of yeast & sugar added by the brewery to help give a kick to fermentation before bottling and what you will "scavenge" from such a bottle will be a different yeast than what the brew was fermented with. Some home brewers like me farm their own strains that they're happy with. I have a strain which I bought commercially but was so happy with I keep it alive in a Erlenmeyer flask in a refrigerator dedicated to being a nursery for yeasts. I decant the liquid from on top of the yeast colony and then add unfermented wort as food which I salvage from prior batches of beer. Sterilization is important in doing this. The Erlenmeyer is sealed with a rubber stopper and has a bubble lock. Each time I remove some stored wort to add to the yeast I re-sterilize the container and seal it just like you would when canning tomatoes & I do this so bacteria can't get in to ruin it. I've had the same strain of yeast for a long time and there's been no contamination. Yet...
You may wonder why I go to all the trouble of feeding & re-feeding the yeast. One reason is because I'm cheap when I can be. The other reason is because I consider it fun to have a "pet" yeast I use for brewing. You must feed these "companion" yeast because in the absence of sugars, yeast still want to eat. What I haven't said before is they will eat other things than their favorite sugar meal. Yeast will eat other varieties of sugar which will create off-flavors which are unwanted in the beer and they will even become cannibalistic & eat their own if no other food is available. Going back to the concept of yeast dormancy which happens when the food is low and the yeast tend to go to sleep; If the yeast is kept in a cool environment ( as my fridge is set to 40f ), the metabolism of the yeast is so slow that little of this "autolysis" or cannibalism will occur. The real importance to the next batch of beer isn't that the autolysis itself will ruin the flavor of the brew, it's more that being in such a state of starvation ruins the health of the remaining yeast and they are not going to be vigorous & vibrant any longer and that will adversely affect your beer from that point on. When yeast have become that weakened it's best to buy a new batch and start over.
A brewer doing this will take a decent sample of this yeast and put it in a sterile flask and introduce a nutrient medium to it and then seal the container with a sterile air lock several days ahead of the brewing day. This is to allow this new colony the time to actively start reproducing & eating. When you then add this actively fermenting yeast to the new batch of beer there is only a tiny lag time between introducing the yeast and having fermentation start. As to the original farmed colony, it's been decimated so you have to add a decent amount of nutrient broth to it as before. If you're going to brew soon you have two options... One is to let the farm batch ferment in room temperature so the colony multiplies rapidly or you can put it back into the fridge for a slower reproductive cycle & simply use sterile technique with the yeast in the bottom of your fermenter from your last batch and fill the container directly with your new brew after it's been chilled. This works fine if you know good sterile technique and plan your brewing on the same day you remove the beer from that fermenter. The last pearl here is when you introduce the nutrient to the farm yeast in the fridge, you must have the nutrient at the same temperature or it will shock the yeast and you may get what's known as a stuck fermentation. Having the yeast at the same temperature as the wort it's going in is a simple rule but one that must be followed. ( Almost like what you do when you bring a new fish home from the pet store and get ready to introduce it to the tank with the difference being you don't float the yeast in the wort... ) Likewise when you add yeast to the freshly brewed batch you want to ferment for if there is a great difference between the yeast's temperature and the wort you will likely have problems. Before you add the yeast let the temperatures of yeast and wort become approximately the same slowly as explained above. Let the yeast reach room temperature on their own and don't put the container of yeast you're going to use in warm water to hurry it along....
When the brew is boiled in the boil kettle, all the free oxygen is driven out of the water. Oxygen greatly helps yeast reproduction and is important in the beginning of each fermentation so that the baby yeast can develop strong cell membranes. Oxygen must be replaced and some brewers shake the fermenter to do just that. Many brewers use sterilized aeration stones to introduce oxygen to the mix. Once the majority of fermentation is over with oxygen becomes a liability as it oxidizes the beer which will completely ruin the brew. For anyone adding air or O2 to the fermentation, it is a short term event and not prolonged. One hour's worth would be plenty.
How to make a Yeast Starter: Click on this link for all the information needed to get a fine yeast starter going in the right way.
To facilitate yeast production I use a stir plate and stir rod. The stir plate has a motor which rotates a magnet. The yeast culture is placed in an Erlenmeyer flask with a sterilized "stirring rod". The motor turns, the rod is magnetically coupled to the spinning magnet through the glass and the yeast gets additional oxygen from the bubbles from cavitation. The yeast also gets a maximal exchange of nutrients because all the cells are swirling freely in solution as opposed to being compressed on top of one another as gravity would wont to do which would keep nutrients from the bottom-most yeast.
My beautiful Stir Plate with warming option for cold days in the basement.
Stir Bars
Yeast Starter in Erlenmeyer with sterile fermentation lock in place.
Now you've entered the fermentation stage of this debacle. The yeasty, hoppy sugar water is now sealed with a single hole rubber stopper which has the bottom of a sterile "fermentation lock" inserted in the hole and this assembly keeps unwanted bacteria out as well as letting the yeast produced carbon dioxide exit the fermenter. This fermenting liquid is kept in the dark from this point on. Ultra violet coming from both daylight & artificial light is not your friend and will react with the hop oils & particles and it will give off sulphur based odors and flavors ( called Thiols) which are different from what you want & expect in your beer. Heck, Thiols are what makes skunks smell so bad & it's the stuff that natural gas providers add to natural gas so you can smell it if it's leaking (natural gas is odorless without this additive). Unless you're Pepe Le'Pew you want to keep your fermenting brew covered. An upside down black garbage bag pulled over your fermenter & with a hole cut in the bottom to poke the air lock through will be perfect. Some people & the commercial breweries ferment in stainless steel. I'm fermenting in Stainless and glass both.
After fermentation is completed you have beer albeit it is still too "green" to drink & it is un-carbonated as well. Fermentation is complete when the yeast has eaten all the available sugars or when the alcohol is too high for the yeast to survive. In beer making, fermentation stops when the food is gone for alcohol levels so high as to kill the yeast are seen in wine & sweet Mead production ( mead coming from fermented honey . ) The brewer either transfers the beer to bottles where first a small but measured amount of corn sugar is first added to the fermenter thus giving the starved yeast something to eat which restarts fermentation. (Corn sugar contains the type of sugar that beer yeast want to eat and if you use table sugar you will find the yeasts giving a funky cidery flavor.) The beer is lightly stirred in the fermenter to disperse the newly added sugar & when you siphon the beer from the fermenter to the bottle it will allow fermentation to restart in the bottle which is your source of carbonation in the sealed bottle ( called bottle conditioning ). I often transfer the beer to a small stainless steel keg like soda comes from in restaurants. If you add a measured amount of corn sugar to the keg to get fermentation it's called keg conditioning. Many people simply add carbon dioxide to the keg from a tank and the beer gets carbonated this way. I prefer to just add the carbon dioxide from a tank. To me there's a difference in the quality of the carbonation & the conditioned is I think better but not much so and with the keg conditioning there's more yeasty sediment once the fermentation is over. Besides... if you add the Co2 you can drink it faster & not have to wait for the fermentation to stop.
Like a fine wine with the yeasty sediment on the bottom, homebrew beer will age gracefully. It will not last as long as wines do but it will last a plenty long time and will improve for years assuming it has that kind of life expectancy in your house. The higher the alcohol content and the addition of higher levels of hops add to the time it takes to "cure" properly. Beers with higher alcohol & hop levels will also last longer on the shelf than beers with less of these ingredients. Commercial beers (& many wines) do not age for the beer was pasteurized before canning/bottling and this killed the yeasts. Because of this and the commercial filtering of beer, there are no yeasts or sediment which contains nutrients to age the brew with and this makes most commercial brews "un-inspiring" to me and many home brewers.
This is a photo of my non-Conical fermenter. It's made by SABCO and has the top of a 10 gallon Cornelius keg welded to the top of a 15 gallon beer keg. Thanks to the Cornelius fittings, there is a "dip Tube" running from one valve to the very bottom of the tank and the other valve is to connect CO2. There is a racking arm inside which allows you to select the height at which you transfer your beer from. This way you can remove beer above the yeast/Trub on the bottom. You can add some CO2 pressure and transfer beer under sterile conditions and higher than the container. There's a removable lid for cleaning or adding fruit to the fermentation. It makes it very easy to use in that you don't have to lift it once you fill it & even if you do lift it, it's completely sealed so nothing splashes. You can gravity feed into the fermenter from the chilled wort and never pick the unit up again while full. Not having to start a siphon ever again is a blessing. Being able to fill a 5 gallon corny keg for keg conditioning is simple. just apply a little CO2 through the Cornelius inlet & you're done. Being able to use an inter-connecting transfer hose from one Cornelius keg to another is a real time saver. Lastly, when you get done transferring the beer you can do one of several things: Clean the fermenter, salvage the yeast to brew with another day or you can start a new batch fermenting immediately using the yeast from the last batch. Just do your transfer when you're ready to fill the fermenter & you can fill through the clear tube in the photo. No Hot side aeration which will ruin the beer, no spilling and no exposure to pathogens to trash the brew. Best thing of all is it's unattended, you don't have to do a thing, just let gravity fill the fermenter. If you want to be really creative you can add an aeration stone at the end of "dip tube" and run a filtered air supply or pure O2 into it at the beginning of the ferment to ramp up the yeast production.
Above is a picture of a five gallon Cornelius keg as is used in the soda industry. If you replace the gaskets and valves called "poppets" and clean them well with an organic cleaner like PBW after their use for soda is over, You have a perfect keg to store beer, mead & wine in. They have an inlet for CO2 , An outlet for the beer and they have a removable lid to gain access to clean. Once a brewer starts using these, they don't want to use bottles anymore. Much easier care & feeding. This is the kind of keg that I transfer my beer from the fermenter into via a closed system. I don't need to open the keg until it's been emptied of beer & needs to be cleaned for the next time. Heh, it's about as efficient and sanitary a method as you can get.
SABCO: Makers of Stainless brewing kettles, Fermenting vessels and accessories.
White Labs: Supplier of yeast cultures used by many home brewers.
Wyeast labs: Supplier of yeast cultures used by many home brewers.
In this wonderful age of litigious non-responsibility you find Safety pin makers having to warn that pins are sharp and electric heater manufactures have to tell you not to put the heater in the bathtub. In 2003 a collection of geniuses in the Katy School district of Huston suspended a 13 year old honor student because she brought a pencil sharpener to school. As it has a blade to sharpen the pencil it is considered a dangerous weapon and she was suspended accordingly. "If we vary from the rules, that's when the rules fall apart," said Katy School school district attorney Christopher B. Gilbert. It is within this same city several years earlier a student suffering from Asthma attacks was suspended for bringing their asthma inhaler to school. Because of asinine laws, idiot legislators, ambulance chasing attorneys and the overwhelming abundance of human stupidity and greed which is increasing in volume on a daily basis, I am forced to make this statement: I completely disavow anything written on this or any web page I have created: Nothing on this or any of my web pages is considered completely accurate. Nothing you read here or follow a link to is considered to be completely correct. Everything you read is my opinion or if relates to a link found on my web page/pages, it is someone else's opinion. Everything on these web pages is strictly an opinion for consideration for discussion and research only.
Isn't having to put this Politically-correct Disclaimer crap on a fun page just the best thing since man learned to walk.
Know what? If there were attorneys back then & the inventor of walking showed someone how to walk, some attorney would have been there to help sue that inventor when their student fell.
For a percentage of the take of course.
( & you know that is the absolute truth don't you. )
Gary Smith
Cheers de KA1J
Any pearls of wisdom are expected & appreciated.
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More to come on this page but I ran out of time. I'll get more added soon!
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