It was standard weekend in the home of Stacy and Aidan, Saturday; Russian courses, a date in the city for coffee and then something a bit stronger afterwards, Sunday; late fees on videos, bopping to Beatle’s CDs, culminating in the creation of the best loaf of bread known to man. Yes we took the next step in throwing off the shackles of consumerism by making our own bread. No bread makers, no videos, just a happy couple laughing, mixing and baking, and finally ending with the spoils of the conflict smeared with the yeasty goodness of vegemite and piping hot green tea.
Over the last six months we have made an effort to live a simpler life, not fully intentionally granted, but bringing much warmth into the house.. There is always dinner on the table for whom ever comes in last. Happy meals cooked with love and fresh food, reducing the processing and unnecessary preservatives (salt excluded), everything from veggie burritos, to lasagnes, to soups of all varieties, stir fries, and of course my world famous caramelised bananas. The most recent addition to the happy recipe book of our lives is our own stout.
It is official I am the luckiest man on earth as the male fantasy of living in a brewery with a beautiful buxom blonde has become a reality. Not since my student days has the nectar of the gods flown so freely in my home, with its gorgeous dark colour, pristine white foamy head, and viscous trails running down my throat. Please note always drink responsibly and if you are going to wear a lampshade don’t let anyone get a photo.
You may ask, to what do I owe this great honour? What has given the greatest gift of all? Not the gods, but much, much smaller, I speak of course of that amazing Eukaryote Saccharomyces cerevisiae, better known to the rest of us as Brewers Yeast.
Fermentation: Ethanol (CH3CH2OH) is produced as a by product of yeast glycolysis, under anerobic conditions… The yeast breaks down Glucose, fructose, (sugars), to create adenosine triphospahte ATP, the energy currency of the cell. The pathway is incredably long and complicated so it is much easier to give a qualitative view of the process… I am sure I can find one of old study posters if anyone wants further info.
The pathway is well shown here http://en.wikipedia.org/wiki/Glycolysis which leads on the aerobic metabolism, via mitachondria very interesting but has nothing to do with beer.
Glucose C6H12O6à 2* pyruvate + 2*ATP + 2 CO2
In production of ATP two molecules of NADH are produced from the oxidation of NAD+ . To reclaim the very usefull NAD+ for further energy generation, the cells ferment the pyruvate to ethanol; and you though they did it just for us.
A very similar process occurs in the body in which pyruvate is fermented through to lactic acid, It would be a lot more interesting if the same pathways of NAD+ regeneration occurred in the body, go for a run feel drunk for the remainder of the day, but as always I digress.
The result as long as the the tub is air tight is alcoholic fermentation, further fermentation occurs after bottling with the priming sugar to create disolved CO2, for that frothy finish. If the Tub leaks it tastes like fruit salad and vegemeite, student beer.
The long and the short of it, I have a beautiful wife, I live on fresh hot bread, home grown tomatos, home cooked meals and superb stout. The down side is my wife now has a taste for stout and I have to share. Life is great.