Quality Control
Producing a quality homebrew consistently is the key to success! Every homebrewer has the capability of monitoring process and final product to determine level of consistency and quality. Obviously a homebrewer will have a different level of quality control than a bottling microbrewery; however, the level of consistent quality should be the same.
Basic record keeping is essential to establishing consistency. There are five major points to controlling quality: Equipment, Wort, Fermentation, Yeast, and Documentation.
EQUIPMENT:
Know your system and its limitations. Many brew systems have weak points that can potentially cause problems. Scratches, dead ends, and shadow areas that do not receive adequate exposure of chemical must be avoided. A consistent cleaning and sanitizing regimen must be followed.
It is important to be certain that you are using proper concentration levels, temperatures, and contact times for your chemicals. Read and follow instructions for use closely. It is impossible to sanitize a surface that is not clean; all organic matter must be removed before sanitation can occur.
The term sanitized is not always well understood. Sanitized does not mean sterile. Good sanitation and sanitary practices lead to limitation of microorganisms but does not guarantee that they are eliminated. A smooth surface that has had all of the organic matter (such as dead yeast or wort residue) removed is relatively easy to sanitize because there is no protection or food for microbes. In contrast, a rough surface or a surface that has not been adequately cleaned is very difficult to sanitize because microbes are able to find protection from your chemical cleaning. Use of hot water as a sanitizer should be avoided. Thermophiles can survive high temperatures, so use of a no rinse sanitizer or a sanitizer followed by a sterile water rinse is essential.
Knowing that your equipment is well maintained, clean, and regularly inspected will form the foundation to consistent, quality beer. In the event of a contamination issue, a well-documented cleaning program will help to take some of the guess work out of determining the source of contamination.
WORT:
Now that you are confident in your equipment, it is time to focus on your wort. If your equipment is clean and well maintained, it is relatively easy to produce stable and consistent wort.
Adequate record keeping will allow you to track the consistency of your wort. It is very important to monitor and record as many points as possible such as original gravity, pH, length of boil, percent evaporation, timing and quantity of hop additions, addition of any coagulants, and any other relevant data. Once again, if you have good, consistent records it becomes much easier to trouble shoot in the event of a problem.
Wort must be boiled vigorously in order to achieve a proper protein break and to kill any possible infecting microbes present. An 8-10% evaporation in 1 hour is a good target to shoot for, but each homebrew setup will have slightly different capabilities. Adequate protein removal prior to running into your carboy is important for beer stability and consistency. Use of kettle coagulants (finings) and a whirlpool will aid in the removal of excess protein.
The fermentability of the wort produced can be checked by a homebrewer in a similar practice as a professional brewery. To accomplish a forced fermentation test (pitching extra yeast into a small wort sample) you will need to measure the original gravity and the final gravity of the fermented wort sample. Once this is done, it is possible to compare the results with the main batch, and be able to determine if your wort attenuated completely. Likewise, you can determine whether there are problems with your fermentation techniques and practices.
If the forced fermentation test attenuated completely and the main batch did not, the homebrewer can conclude and make changes to his mashing and fermentation procedure.
Tasks or procedures to check if the fermentation is not appropriate:
- Pitch rate
- Aeration
- Fermentation temperature
- Yeast health condition and management
FERMENTATION:
Once the wort is transferred to the carboy, some additional information can be taken to keep track of a good fermentation or to catch any issues on time.
The following information should be kept on records from each homebrew batch:
- Date
- Time
- Temperature
- Mash pH
- Wort pH
- Starting gravity
- Final gravity
- Actions
The starting gravity should be taken once the wort is ready to be transferred to the carboy. Unless your homebrew setup is outfitted with a sample port, it is not necessary to take a density reading again until there are signs of the fermentation slowing, such as reduced airlock activity. At this point, take a density reading until fermentation is complete.
Taking a pH reading prior to fermentation with pH strips or an electronic pH meter is optional but not necessary for traditional styles. However, if you are making a kettle sour, you will want to have the necessary tools to monitor the progression of the pH drop and when you have reached your target.
The best quality control management balances sufficient sample and data collection while being cautious to avoid contamination. When taking samples, keep everything sanitized to avoid unnecessary contaminant risk. Determine when and how much sampling is suitable for your system and experience.
YEAST:
Your equipment is properly cleaned and maintained, your wort is consistent and stable, now make sure all of your diligence and hard work are rewarded with consistent predictable fermentations resulting in great beer.
Yeast performance is tied to many factors. Everything that you do during the brewing process will have an effect on the yeast that is converting the sweet wort into beer. Once again, good record keeping on the entire brewing process will help to maintain consistency and to locate inconsistencies that could be causing a change in yeast performance or beer quality. Pitch rates and oxygenation were covered previously, but the importance of these two factors cannot be stressed enough. Adequate pitch rates and oxygenation will help to minimize the impact of inconsistencies in the brewing process.
DOCUMENTATION:
Documentation and Tracking
The importance of good documentation cannot be over emphasized. Information can be kept in a logbook or on computer file, which tracks all information pertaining to the brew. The following are suggestions for documentation and tracking information.
Yeast Information
- Strain number and name
- Package Code
- Best if Used By date
- Retailer & pick-up or shipping conditions
- Quality of activation (amount of swelling and time to swell)
- Starter size or # of Activators pitched
- Beer style, batch volume, date
- Temperature at pitching
Fermentation Information
Good fermentation records are valuable when evaluating yeast performance over a period of time.
Brewing specs per batch:
- Wort cooling/Run in time
- Wort aeration
- Fermenter volume
- Yeast pitching details
- Starting and final gravity
- Temperature
- Airlock activity
- Cooling time and date
- Forced fermentation sample (optional)