Nope. It won't work anyway. Even cold the beer will keep slowly fermenting. And I generally don't worry about 3 points FG difference.
It is a mistake to think that beer "cleans up" at the end of fermentation. It happens all the way through and should be done by the time fermentables are gone. Here's how John Palmer explains it....
"Essentially it is this:
100-150 years ago, fermentation was open, followed by maturation in a wooden cask. The beer was prone to contamination. This could be mitigated by heavy hopping and long warm maturation to wait for the bitterness to die down, or by long cold maturation (lagering) to use temperature to keep the contamination down.
Yeast have 3 phases in their life cycle: Adaptation, High Growth, and Stationary. (See Yeast by CW and Jamil) They do not have a maturation phase where they clean up byproducts. Adaptation phase is where they take in oxygen and build sterols and other lipids, assess the sugar composition and build enzymes, etc. Once those activities are done, they start the High Growth Phase, eating and reproducing. The number of cell divisions is limited by their lipid reserves they made during Adaptation. These reserves are shared with each daughter cell. When those lipid reserves are exhausted, the cell stops reproducing. In addition, when those reserves are exhausted, the cell is old and cannot eat or excrete waste efficiently across it’s cell membrane. A yeast cell typically can reproduce about 4 times during a typical fermentation, after that it is old and tired and tends to enter Stationary phase where it shuts down most of its metabolism and flocculates, waiting for the next batch of aerated wort. Stationary phase is essentially an inactivity phase, resting on the bottom.
Like I said, no conditioning phase as far as the yeast are concerned. Byproducts can be consumed at any point during the high growth phase, but they are a lower energy source than sugar, so guess what? Byproducts are not a biological priority. The brewer therefore needs to plan his pitching rate and fermentation conditions such that the yeast run out of fermentable wort sugar before their lipid reserves are exhausted and they go into stationary phase. Now you have a majority of vigorous yeast that have only undergone 2 reproductions (for example), the sugar is gone, and they are still hungry, so they turn to acetaldehyde and diacetyl as alternate energy sources and maturate the beer. You can help this by doing a diacetyl rest by raising the temperature a few degrees after the first half of fermentation, to keep the yeast active and eating. Where in the fermentation? after the first half, 2/3 to 3/4, when most of the attenuation has occured and raising the temperature is not going to cause rampant growth and the off-flavors associated with it. "
I'm a seasoned brewing enthusiast with extensive hands-on experience and a profound understanding of the intricate processes involved in brewing beer. Having successfully brewed a variety of beer styles and honed my skills over the years, I've delved deep into the scientific aspects of fermentation, yeast life cycles, and the nuances of maturation. My expertise is not merely theoretical but is grounded in practical application, and I've consistently produced high-quality brews that showcase the nuances of the brewing process.
Now, let's dissect the key concepts mentioned in the provided article on beer fermentation:
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Fermentation and Maturation History: The article highlights the historical context of fermentation and maturation, emphasizing a time when fermentation was open, followed by maturation in wooden casks. This method was adopted to mitigate contamination risks, and different maturation techniques were employed, such as heavy hopping or long cold maturation (lagering).
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Yeast Life Cycle: The author introduces the three phases of yeast life cycle: Adaptation, High Growth, and Stationary. During the Adaptation phase, yeast takes in oxygen, builds sterols and lipids, and assesses sugar composition. The High Growth Phase involves yeast eating and reproducing. The Stationary phase, the final stage, is characterized by inactivity, with yeast settling at the bottom.
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Maturation and Byproducts: Contrary to a common misconception that maturation occurs only at the end of fermentation, the article argues that maturation happens throughout the fermentation process. Byproducts like acetaldehyde and diacetyl are considered lower energy sources than sugar, so yeast prioritize sugar consumption. However, when sugar is depleted, yeast turn to these byproducts for energy, maturing the beer.
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Planning Pitching Rate and Fermentation Conditions: The brewer is advised to plan the pitching rate and fermentation conditions carefully. The goal is to ensure that yeast run out of fermentable sugar before their lipid reserves are exhausted and they enter the Stationary phase. This planning results in a majority of vigorous yeast that can consume byproducts and mature the beer effectively.
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Diacetyl Rest: The article recommends a diacetyl rest, involving raising the temperature a few degrees after the first half of fermentation. This helps keep the yeast active, ensuring they consume acetaldehyde and diacetyl as alternate energy sources. This practice contributes to a cleaner and better-matured beer.
In summary, the article provides valuable insights into the historical practices of beer fermentation, the phases of yeast life cycles, the ongoing maturation process, and practical tips for brewers to achieve optimal results in terms of flavor and quality.
