When thinking about vodka and how many calories it has, it’s interesting to first consider the process of producing vodka and what it comes from. From most popular to least, common ingredients include: wheat, rye, barley, grapes, sugar. Vodka can be distilled from nearly anything with a carbohydrate in it, but it seems to make sense to use inexpensive inputs, rather than exotic fruits.
When making vodka from a complex carbohydrate source, the source first has to be broken down into a simple sugar for fermentation to begin. Alcohol producing yeast is unable to act on long-chain carbohydrates. Once the sugar solution is fermented, distillation extracts the alcohol from the water, yeast and sugar. However, this alcohol is crude and harsh tasting and needs to undergo filtration to become the beverage that we have come to enjoy today. This filtration process allows brands to differentiate taste.
Some brands filter their water source as well as the alcohol, and are more willing than others to disclose the materials they use. This process can be patented and is largely responsible for variety of taste and smoothness found among today’s vodka brands. It should be noted that the alcohol that undergoes filtration is pure ethanol and it is watered down at the end to produce the alcohol by volume that the end consumer knows.
When it comes to calories, it’s inconsequential what grain is used. The reason is that the vodka is so purified of other sources of calories (carbohydrates, fat and protein) that we can determine the calorie content directly from the alcohol by volume. Using 40% ABV, vodka has:
97 calories in a shot
66 calories per 30mL (standard UK serving)
Of course, not every single commercially distributed vodka is 40% ABV, so if it differs, the drinker will have to make adjustments if trying to estimate its calories. The same concept applies to those producing vodka at home. Assuming that you’re producing a product with no residual sugar, the calories are directly proportional to alcohol by volume. And just a reminder for any low carb dieters out there, vodka has zero carbs once it reaches the shelves.
For more information, check out Joe Bauers’s article on vodka and dieting or his vodka nutrition blog.