The science of carbonation: Why your serve tastes better when using higher quality, carbonated mixers

Mixers have long been overlooked by consumers and the on-trade alike, playing - at best - the supporting role to spirit’s top billing, but drinks pioneers Franklin & Sons are on a mission to make us understand our mixers better. They are also determined to give something back to the drinks industry, so are starting with the people who know their beverages best and truly have the power to influence the way the rest of us drink; the people behind the bar.

Despite their prevalence in many of our favourite drinks, mixers are rarely subject to the same level of scrutiny - and shown the same respect - as spirits. And yet, mixers affect the entire quality of a finished drink and, in turn, the consumer’s whole drinking experience. They can overpower, enhance, or completely ruin a spirit or cocktail and, as Franklin & Sons are determined to demonstrate, it isn’t just about flavour; it’s also about fizz. With its ability to heighten flavours and aromas, carbonation is the key to a great mixer, and mixed drink.

The history of carbonation is believed to date back to the 1740s when William Brownrigg became the first person to aerate water with carbon dioxide (CO2), but it was Joseph Priestley who invented carbonated water, largely by accident, when he infused liquid with CO2 by suspending a bowl of water above a beer vat in 1767. However, it was not until the early 1780s that carbonated water began being produced on a commercial scale, first by Thomas Henry of Manchester and then by a certain Johann Jacob Schweppe who initially bottled soda water but ultimately created the soft drink industry as we know it today.

Franklin & Son’s story began in 1886 when (what was then known as) Franklin & Brothers was established by George, Albert and Frederick Franklin. Inspired by the innovative drinks Frederick had experienced in America, the brothers were determined to work only with the finest natural ingredients - a commitment which continues to this day as Franklin & Sons eschew artificial flavours and preservatives - and also dedicated themselves to the craft of carbonation.

Carbonation is the process of dissolving carbon dioxide - which is inert and tasteless - into a liquid. The CO2 then acts as a catalyst, releasing scents previously locked within the liquid, and carrying aroma compounds such as esters and aldehydes up and out of the drink as the carbonated bubbles rise and pop at the surface. In doing so carbonated water can also intensify some aromas over others; for example, the more volatile esters in a spirit may be tempered by the water molecules, while the lighter, fruitier aromas may appear enhanced.

But CO2 doesn’t just affect aromas, it can also alter our perception of flavours. A 2009 study by the US National Institutes of Health discovered that it is the sour-sensing cells in our taste buds that are responsible for detecting CO2, and consequently trick our taste receptors into perceiving a sourness that's not actually present. The fizzier the drink the greater the perceived sourness, which is why Franklin & Sons (whose products tend to sit at the top end of the normal range for a mixer of 6-8g CO2 per litre) deliberately reduce the carbonation levels in their citrus juice drinks to prevent an overload of sour taste signals and ensure a balanced flavour profile.

It is this knowledge and understanding that Franklin & Sons hope to pass onto the on-trade through their advocacy programme. Conscious that the hospitality industry has relied on bartenders being self taught for far too long, Franklin & Sons’ programme is designed to genuinely support and educate bartenders by passing on a wealth of tips and tricks. For example, did you know that even an unflavoured soda water will alter the perceived balance of a cocktail, that due to tighter molecular bonds a colder soda is a fizzier soda, and that a clean glass means no unwanted nucleation points where CO2 could escape prematurely?

In addition to sharing their own area of expertise, Franklin & Sons also bring in other industry experts to add value to their immersive sessions, as well as giving bartenders an opportunity to showcase their skills, gain publicity and win cash prizes in their national Flavour in Motion cocktail competition.

In this way Franklin & Sons are not only investing in their own business and brand, but also in the people who serve and create cocktails with their mixers. And rest assured this is not just about becoming the mixer brand of choice for bartenders, but also, and more importantly, about elevating the cocktail category and - by placing themselves in the education space - about giving back to the hospitality industry.