Distiller’s Workbook exercise 9 of 15

Double Grain Bill White Dog

This exercise is a predictive tool for exploring the sensory qualities of new grains. Unfermented grains are added to an un-aged grain based spirit and simply re-distilled. The product is quite fun but definitely has limitations that will be explained.

The inspiration for this exercise was the Peruvian mosto verde brandy making technique and the new proliferation of boutique grains that are readily accessible at home brew shops. In mosto verde Piscos the grapes are not fermented to dryness before distillation so as to create an exaggerated ratio of aroma to alcohol and a similar idea can be used with whiskey. Unfermented grains can be added to a whiskey and re-distilled adding extra aroma but not extra alcohol. The cost of the grain is so low and the range of aromas is so large that you can have a lot of fun with the technique. Shooting in the dark on your grain selection is a good strategy, but also feel free to try an Octoberfest grain bill.

We experimented widely because there are so many grains available. Each grain has a different distribution of olfactory-sweet and olfactory-dry aromas. Flaked rye is a notable rye expression with an apple-like olfactory-sweet-fruitiness in addition to its typical olfactory-dryness. The aroma of Belgium aromatic malted barley has a small amount of dark, malty olfactory-sweetness contrasted with an elegant olfactory-bitterness. Both coffee and chocolate roasted rye malts are dominated by olfactory-dryness and can be nice components of a blend, but if left uncontrasted they feel as though something is lacking.

A particularly unique grain we experimented with was an acidulated malt. The rye malt gets inoculated with lactic acid producing bacteria which coats the grain in white acid crystals. Acidulated malts are typically used for sour beers. Lactic acid is a volatile fatty acid (boiling point 122°C but with a relative miscibility that makes it volatile during beverage distillation) which means small amounts of it will come across in the distillate. Unlike acetic acid which will corrode a copper condenser, lactic acid is not strong enough or is not typically encountered in high enough concentrations. We were not sure how much of the acid was actually captured in the distillate, but we did notice a subtle creaminess was present in the distillate.

Exploring the aromatic character of grains in this way can provide an educated guess of how a fermented counterpart may turn out and could inspire someone to elaborate their experiment into a full-fledged fermented and distilled whiskey. This technique can only provide a glimpse of what lies ahead because aroma changes somewhat during fermentation as many new aroma compounds are produced (the technique also allows exploration of the magnitude of change after fermentation).

Using a white dog as opposed to a vodka will give markedly different results and make the predictive rendering much closer to a true fermented product. The white dog contains a selection of the generic congeners that are a byproduct of fermentation, such as ethyl acetate and acetaldehyde, while a vodka does not. These congeners, even when below the recognition threshold, are critically important to defining the overall experience. The rendering created in the exercise will have a selection of these congeners, but not in the unique proportion of the true fermented version.

To further explore a limited view of a whiskey’s future on the nano-scale, a novel fake aging technique can be used to synthesize the tension between the volatile aroma of a new grain and the non-volatile contributions of a barrel. Samples of commercially produced and sufficiently barrel aged spirit can be put into a food dehydrator to remove the volatile fractions at fairly low temperatures. What remains is barrel essence which is essentially the perfect soup of non-volatile acids and tannins. The newly distilled spirit can be used to reconstitute the barrel essence and thus quickly take on the pH and non-volatile characteristics of an aged spirit. It is hoped that these techniques inspire small scale distillers to deepen their involvement and eventually pursue the traditional route. Every garage or basement should have a sleeping barrel of whiskey.


500 mL unaged whiskey a.k.a. “white dog” (the gentleness of wheat is a good place to start)

100 g unfermented grains (with a white wheat whiskey a contrasting grain like an “Aromatic Belgium” malted barley is extraordinary)

7 g tartaric, malic, or lactic acid (optional acid catalyst)

250 mL water

Mix and re-distill together slowly on low reflux until the thermometer on the still reads 93.33°C. Going past 93.33°C may result in a cloudy distillate and or unpleasant cooked aromas. The extra water is added to reduce the chances of grain solids scorching on the bottom of the boiler.

Using your hydrometer re-cut the distillate to your desired proof (recommend 80-90).

Optionally, to synthesize the pH and non-volatile characteristics of an aged spirit, de-hydrate a volume of aged Bourbon proportional to the amount you want to fake age then reconstitute the resulting barrel essence.



1 oz. “Belgium Aromatic” aromatized white wheat whiskey

1 oz. rosé vermouth

1 oz. Cynar

dash Peychaud’s bitters


Black Dog

2 oz. “Belgium Aromatic” aromatized white wheat whiskey

4 g. non aromatic white sugar

4 dashes Peychaud’s bitters

rinse of Absinthe


Williamsburg Red Hook (apologies for the obscurity of the grains and of this cultural reference)

2 oz. “Belgium Aromatic” aromatized white wheat whiskey

.75 oz. Punt y Mes

bar spoonful maraschino liqueur

2 thoughts on “Distiller’s Workbook exercise 9 of 15

  1. “Wash that is not fully fermented is at risk of causing foul distillations; this
    exacerbates any potential ethyl carbamate problem, and hence distillation of
    short fermentation washes should be avoided.” – from Whisky: Technology, Production, and Marketing (p. 161)

    This statement unfortunately is not elaborated in the text. It is hard to say if there is a difference in results regarding ethyl carbamate if the grains under go saccharification or not. And then would mosto verde Piscos be dangerously high in ethyl carbamate?

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