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Dr Michael Lewis, Professor, University of CA

Dr. Michael Lewis is one of the Brewing Industries most respected authorities on the science of brewing. As professor of brewing sciences at the University of California, he is credited as a pioneer consultant to the micro brewery industry. Dr. Lewis is one of only 50 scientists in the world elected a Fellow of the Institute of Brewing and a recipient of the 1985 Award of Merit from the Master Brewer's Association of the Americas. Having published more than 100 scientific papers on topics related to brewing, is it any wonder why, under his careful guidance, The Beer Machine Home Microbrewery has received so many compliments for it's design.

“The brewing process is a biological process sensitive to environment and cleanliness. Even in the most sophisticated breweries, occasional fermentations do not perform as expected. Although The Beer Machine Home Microbrewery was designed to protect the delicate fermentation process, it is possible that the unexpected may occur. However, most 'surprises' will fall into four main categories: sweetness, carbonation, haziness, and sourness.

SWEETNESS -The Beer Mix contains maltose. Maltose will leave your beer sweet unless it is completely converted to alcohol and CO2 during fermentation. Sweetness in the beer is always due to a lack of complete fermentation. The proper amount of yeast is important. For this reason we recommend using the yeast supplied with your beer mix. If the fermentation is incomplete or 'stuck', the yeast may have been killed by using water too hot to dissolve the syrup or powder. It could also be rendered to sluggish by using very cold water and a cold location for fermentation. Putting The Beer Machine Home Microbrewery in the refrigerator too early has the same effect. If within the first 24 hours a foaming up, or fermentation 'boil' occurs; then the fermentation started well, however, if the beer taste is sweet, then the fermentation was likely cut short by cold temperatures.

CARBONATION - In The Beer Machine Home Microbrewery carbonation arises from two sources. The fermentation process produces CO2 naturally and the pressure control valve will trap a substantial amount of this gas. The second, and more obvious source is the CO2 cartridge provided. If the beer is flat and tastes sweet, part of the problem lies with an incomplete fermentation which would produce less CO2. If it is not sweet, but flat tasting, the fermentation gas could have escaped from an improperly sealing gas valve, unsecured cap or other seal leak. Once the leakage is identified and stopped, additional carbonation can be supplied with the CO2 injector. BEFORE USING THE CO2 INJECTOR, the beer should be refrigerated first as it has to be thoroughly cold to carbonate well.

HAZINESS -This is caused by either yeast remaining in suspension or a "chill haze". We have worked very hard with our syrups and powders to prevent the latter, so the most likely cause of haze is the lack of proper yeast settlement. Settlement (called flocculation) takes time, and coldness, and requires the fermentation cycle to be complete. Again, if there is residual sweetness, this indicates whether the fermentation was not properly completed. The cure here is a complete fermentation and a long cold storage. Also check to be certain that the float is dispensing your beer from the top of the brew and is attached to the dispense tube. Otherwise you'll be pouring from the bottom of The Beer Machine Home Microbrewery.

SOURNESS -This may show up from time to time and is caused by bacteria growing in the beer, thereby producing acid. If your beer tastes slightly vinegary it is certainly bacteria. These kinds of faults may show up in beers kept for a long time, especially if they are warm. Alternatively, The Beer Machine Home Microbrewery may have been inadequately cleaned and sanitized. A simple chlorine or bleach rinsing prevents disappointments.“