What's The Real Difference In Draft Beer?

Beer is great, but is draft beer better? Beer lovers have debated for years whether canned, bottled, or draft beer tastes better, and there is no definitive answer. Draft beer is made by pouring beer from a keg into a glass or mug, while canned or bottled beer is packaged in a sealed container. Some people believe that canned beer tastes better because it's been protected from light and air, but the longer it's stored, the more the flavors start to break down and fade. On the other hand, bottled beer is often packaged in a way that protects its contents, but it is still exposed to light, air, and temperature changes. Draft beer is generally fresher, as it has been brewed within the last few weeks, resulting in more pronounced flavors and a smoother taste.

Oxygenation

Oxygen is a crucial factor in brewing beer. While it is usually considered a "supervillain" in the process, as it can stale the beer and decrease its shelf life, oxygen is essential for healthy yeast development. Yeast requires oxygen to reproduce and create healthy cell walls. This results in better attenuation, more complete fermentations, and reduced fermentation times.

It is important to note that the source of oxygen makes a difference. Using pure oxygen can achieve higher dissolved oxygen levels, while aeration with air is limited to around 8 ppm due to air only containing 21% oxygen. Additionally, the size of the bubbles matters, with smaller bubbles having a larger surface-to-volume ratio, which allows for more efficient oxygen absorption.

While oxygen is necessary for healthy yeast, over-oxygenation can lead to flavor problems. Most yeast strains can handle high amounts of oxygen, but there is a point where they stop producing sterols. At this stage, excess oxygen can lead to the creation of more flavor compounds, which may negatively impact the taste of the beer.

In conclusion, oxygenation is a critical aspect of brewing beer. It ensures healthy yeast development, which in turn affects the fermentation process and the overall quality of the beer. By understanding the science behind oxygenation and yeast requirements, brewers can make informed decisions about the oxygenation methods and levels needed to produce the desired beer.

Packaging and storage

Draft beer is packaged and stored in kegs, which are kept in a controlled environment. Kegs protect the beer from light exposure and help maintain a consistent temperature, which is crucial for preserving the beer's freshness and flavour. Unlike bottled or canned beer, draft beer is typically consumed soon after it's been brewed, ensuring the flavours of the hops and malt are more pronounced.

Bottled beer is typically packaged in 12-ounce glass bottles, either green or brown. Green bottles are popular for lagers, but they can increase the beer's susceptibility to skunking. On the other hand, amber glass bottles are generally considered safer and suitable for heavier, fermentation-driven beers that can benefit from a little extra aging. Bottled beer is more susceptible to light, air, and temperature changes, which can impact its flavour over time.

Canned beer has historically been associated with mass-market beers, but its perception is changing. Craft brewers are increasingly adopting cans due to their ability to block all UV rays, preventing flavour compromise and skunking. Cans also have the advantage of cooling down faster than bottles, reducing the time between shelf and serving.

While draft beer has the advantage of freshness, it's important to consider the maintenance of the tap lines. Busy bars with numerous taps may struggle to maintain their draft systems properly, leading to the development of bacteria that can impact the beer's flavour. Therefore, proper maintenance and cleaning of draft beer equipment are essential to ensuring a positive drinking experience.

Carbonation

When dealing with beer in a keg, there are three constituent parts: the liquid beer, the carbon dioxide dissolved in the beer, and the carbon dioxide in the atmosphere of the headspace above the beer. The interaction between these parts is the key outside influence on the system.

The rate of dissolution of CO2 in beer depends on temperature and pressure, the degree of under or over-saturation, and the interfacial surface area between the CO2 and the beer. When pouring from a draft system, the carbonation level/mouthfeel differs from bottled or canned beer due to the constant pressure being applied to the liquid within the keg.

To avoid issues with carbonation, the beer should be kept at the right temperature and pressure. If the beer is too cold, it may seem flat as the CO2 stays in solution, only coming out of solution as the beer warms up, which can cause belching and a feeling of being overly full. Under-pressurizing a keg will cause the beer to go flat over time as CO2 slowly bubbles out of the solution. Conversely, if the applied gas pressure is too high, the beer in the keg can quickly become over-carbonated.

The correct pressure for a draft beer system will ensure a perfect pour, preventing a trickle of liquid or a blast of foam. The ideal pressure depends on the style of beer being poured. For instance, most ales are poured at 7 to 13 psi, while stouts are poured at 35 to 38 psi.

Sanitation and quality control

The quality of draft beer is paramount to customer satisfaction and retention. The beer's journey is just beginning when the keg is tapped, and it is crucial to ensure the beer is delivered as the brewer intended.

One of the most important aspects of maintaining draft beer quality is regular and proper cleaning of the draft lines. Unclean lines can introduce unwanted bacteria, wild yeast, or microorganisms, leading to off-flavors and an unpleasant drinking experience. Beer stone buildup, which can flake off into the beer, and biofilms can also affect the balance of the dispense system, resulting in foamy pours and wasted beer. Therefore, it is essential to implement a regular cleaning schedule and follow proven cleaning methods. The Brewers Association recommends cleaning lines with a caustic solution every two weeks and performing a quarterly acid cycle to remove beer stone buildup.

In addition to line cleaning, other components of the draught system, such as keg couplers, faucets, and FOB devices, should also be cleaned regularly. Proper glassware sanitation is another important factor in maintaining beer quality and ensuring a positive drinking experience.

Consistency is key, not only from batch to batch but also from the first pint to the last pint of each keg. By implementing quality control measures and maintaining sanitation standards, establishments can provide customers with a memorable taproom experience, ensuring they keep coming back for more.

To assist with quality control and sanitation, the Brewers Association has developed the Draught Beer Quality Manual, which provides detailed information on line cleaning, draught system components, gas dispense and balance, proper pouring techniques, and sanitation practices. This resource helps draught installers, wholesalers, retailers, and brewers deliver the freshest and most flavorful draught beer experience to consumers.

Aromatics

The aromatics of a beer play a significant role in its overall flavour profile and drinking experience. The way a beer is packaged and served can have a big impact on its aromatics, and therefore its perceived flavour.

Draft beer is served straight from the keg, which is a closed system that protects the beer from oxygen ingress and light exposure. This means that draft beer is often fresher and has a more vibrant taste compared to bottled or canned beer. The controlled dispensing process of draft beer also contributes to a smoother mouthfeel and a creamier head.

Bottled and canned beers are packaged and sealed before distribution. The materials and capacity states of the containers can influence the taste of the beer. Glass bottles, for example, offer better protection against air and light, which can affect the freshness of the beer.

However, during the canning or bottling process, the beer is exposed to the environment, which can lead to oxygen pickup and the loss of volatile aromatic compounds. This can result in a decrease in carbonation and a change in the flavour and aroma of the beer.

Additionally, the shape of the glass or container from which the beer is consumed can also affect the aromatics. Draft beer is typically served in a glass, which allows for a wider opening for the aromatics to be perceived. Bottles and cans have smaller openings, which can make the aromatics less perceptible.

Overall, the packaging, serving, and consumption methods of beer can significantly impact its aromatics and, consequently, its perceived flavour. Draft beer often offers a more aromatic drinking experience due to its freshness, controlled dispensing, and open container. However, proper handling and storage of bottled and canned beers can also result in a desirable aromatic profile.

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