Confections: Baking with Rum

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When economy is the concern, baking with the finest pricey rums may be a better value proposition than drinking them.

What we are after is radiant exuberance and remarkable persistence. Grand arôme rum should be trending in every Michelin starred pastry department. However, the humble origins of baking with rum looks a little different. The best description of what industrial bakers were after comes from the 1975 Rum Symposium:

[…] After the Second World War, goods for daily use were insufficient and their qualities were poor. Materials of confectionary, such as butter and wheat flour, were not an exception. Heavy rum was used in order to improve the taste and flavor of cake made from those bad materials. Thus, rum has been developed not as a drink, but as a confectionary use, and in Japan heavy rum was wanted. […] We had to study rum making under very different conditions from West India.

Poor quality butter and wheat flour? A few descriptions of baking with rum from the 19th century include the idea of including it when dealing with substandard flour for bread making. What were they after? The esters, the ethanol, the rum oil (damascenone)? What are the economics? Was/is it excise tax free? Was it competing with the price of vanilla beans? Who could tell us anything? E. & A. Scheer? Or, is this the realm of received wisdom where something starts remarkably clever and astute, but through the generations, descends into because we always have.

To investigate this history, I propose we all make brownies together and bring it to life.

Commercially available brownie mix gives us a reproducible standard to share observations. The recipe is also remarkably easy to execute so there is no tendency to procrastinate. This high quality brownie mix is roughly $5 at Target and requires nothing additional but 1/2 cup of oil, 2 oz. water, and an egg. To include the rum, I simply put 1 tablespoon (15 ml) into the 2 oz. measure of water. I also successfully executed this as half batches to try two rums. I mixed everything together as described on the package then stirred in 7.5 ml of rum after dividing the batter into two baking dishes. The batter bakes for roughly 45 minutes at 325°F.

What happens? A mere 15 ml is too much for some rums like the Jamaican Golden Devil and the result is extremely salient if not over the top. It is an aroma to behold! The character seems especially congruent with chocolate, but too intense as I made it. My tasting panel still loved experiencing the results and everyone recognized the character. It is worth redoing to reduce the usage rate.

The New Zealand grand arôme from Callum Upfold was also too much at 15 ml and the character less congruent with chocolate. However, it clearly yearned for other pastry applications. It will go in my sticky toffee pudding.

Providence from Haiti, which I particularly enjoy in cocktails, got lost. Some lighter rums do not have what it takes.

The economics of this weighed against the sensory results are interesting. Golden Devil was a $100 bottle so the 15 ml rum addition cost $1.50. I entertained eight people (8 portions) with something incredibly special dramatically cheaper than giving them each a drink. Many premium vanilla extracts are over $100 per liter though I’m not saying rum can be a 1:1 stand in.

Baking with certain rums may be a better value proposition than trying to serve them as a beverage. After comparing the price to flavor a dessert against a vanilla bean, my restaurant was interested in buying grand arôme rum, but not interested in trying to serve the product at the bar. With proper education, the most pricey offerings of Velier may commonly purchased for baking and used only 1 tablespoon at a time. Can they sell me 500 ml of a baker’s blend?

Numerous gelified baking rums exist on the market (modified with xanthan gum or CMC E444 thickener) and likely source from Galion in Martinique, but the rum is not exceptional and does not show anything near the highest potential of the concept. They may be legacy products and on average shadows of their former selves. Rum for terrines is often denatured with salt or even pepper and Bardinet may still offer those. Many of these products become legally denatured to avoid beverage taxes which can be a significant savings. However, it becomes incredibly special to be able to bake with something you can also present as a beverage. Famed chef Charlie Trotter made sorbet with Chateau d’Yquem’s sauternes.

How can we articulate what happens at a sensory level when grand arôme rum is used as a flavourant? Often ordinary ingredients like commodity coffee are sort of homogenized to blandness and stripped of all origin. They lack nuance, intensity, persistence, and intrigue. I can certainly enjoy commodity coffee but it gets fatiguing. Fine single origin light roast coffee has all the dimensions commodity coffee is missing but at prices few can afford and volumes where it is scarce.

Adding rum is a way to elevate confected products and add categories of persistence and intrigue especially for mass market scale where 100% commodity inputs must be used. Grand arôme rum is less scarce than good butter. What we need is a new generation of flavor formulators understanding a clear rational for rum as a flavorant rather than received wisdom for legacy products.

Baking with rum may also not be about the esters though they no doubt help. It is remarkable how much aroma the brownie batter holds onto after being baked for 45 minutes, but what happens to all the ethyl acetate, the most volatile and predominant of all the esters? Artificial ethyl−butyrate is no stranger to industrial confections. There is no reason for the formulator to insist upon it from a natural source. Congeners of super natural persistence and radiance like damascenone may be the biggest prize and there is no food safe synthetic alternative. Batavia Arrack is known to support chocolate in flavor formulations and it is also better known for damascenone than it is for esters.

Adding ethanol to flour has other benefits worth being aware of, but I do suspect when it comes to practical baking, aroma rules the day. Greg Blonder shares some of the science:

Adding vodka to flour performs FOUR functions. First, on a volume basis it contains 40% less moisture than water. Less water develops less gluten, softening the dough, and enabling it to dry out faster. Secondly, the alcohol-extracted lipids modifies the kneaded structure, creating a flaky microstructure. Third, it allows moisture to uniformly penetrate the dry flour, eliminating grittiness and improving uniformity. And fourth, vodka helps break apart long gluten chains, improving tenderness.

A single tablespoon into a batch of brownies may not match the functions Blonder is describing but I do not have enough experience to say. I suspect if rum is incorporated to the classic vodka pie crust trick, it will have to be diluted with the vodka.

Where do we go next? The next thing to do is scour the flavour formulation literature for observations on how genuine grand arôme rum was use in mass market products like biscuits and cookies. Producers like Hampden need to be shaken down for any known information on how marks were used by commercial bakers as unglamorous as the information may be (inferior butter and flour). We also need to understand the comparative index of persistence between grand arôme rum and vanilla extract to help pastry chefs hit more successful formulations with less effort and better understand recipe economy. Rum just may be the next vanilla bean.

[I have tried follow up batches with less intense rums and it got me thinking. What I suspect a mass market baker may be interested in is a flavor constant when they are subject to other inputs changing due to large volume sourcing constraints. Rum takes the pressure off other ingredients to contribute stable identity to the product. What if you stop getting your flour from the Ukraine due to a war? What if your chocolate origin changes as well? A flavor constant in your formula helps you weather changes to your surrounding formula, minimizing loss of a stable identity. It may also help you seize opportunities. If someone is offering you a large quantity of chocolate or flour at a discount, you may be able to use the new product and improve your margins because the constant creates a buffer to changes in character. We can also start to put a dollar value on these things. We have the known price of a distinct rum mark with a certain usage rate versus substantial changes to other inputs with much large usage rates, some being quite pricey like chocolate. Of all the ingredients, rum may have the most stable price of anything you can rely upon for flavor. The two less intense rums I tried could be felt in the formula, but were not overly salient. It would take a triangle test to identify them and simple preference tests versus controls to understand their impact. Rum as an integrated flavorant for mass market products may be an overlooked strategy in a time of supply chain issues and unreliable commodity prices.]