A mash is mixing ground grains (typically rye, corn, malted barley, and wheat) with water and yeast. The mixture will go through the fermentation process to produce alcohol. American whiskey is, by definition, a distilled spirit that uses grains as a raw material. While growing, plants create sugar through photosynthesis and the energy that they don’t use immediately is stored in the form of starch (a complex carbohydrate) which is most highly concentrated in grains and seeds. Distillers take those grains, grind them up, cook them, and add some enzymes to convert those complex carbs into simple sugars that yeast can eventually use and turn into delicious alcohol. Sour mash whiskey is produced by distillers when producers use a part of the previous batch’s spent mash in the next batch’s fermentation. The sour or spent mash is vital to lower the new mash’s pH level and inhibit other microorganisms from growing and spoiling it. Sour mash whiskey is a method distillers use to create whiskey, but the final whiskey doesn’t taste sour. The souring technique adapts its name from sourdough starter, which is a process involved in making bread. The slop contains no nutrients, alcohol, sugar, or living yeast. Still, it contains nutrients and the acid required to keep the next batch of mash ‘healthy’ pH levels. It inhibits other bacteria from spoiling the taste. We think Catherine was quite thrifty and innovative.

The distillers at Brown-Forman are planning to release a small-batch whisky in 2026 based on Catherine Carpenter’s unique sour mash recipe. Sour mash basically refers to a particular process used by distillers to add a specific flavor to the whiskey. Bourbon is a category of American whiskey made following distinct requirements and restrictions.Catherine could not read or write, but that didn’t stop her—she probably dictated her recipes and weaving patterns to one of her children, who wrote them down in a neat cursive hand. Keep up this process of fermenting, replacing half of the mash with fresh, and using the spent wort to refill the fermenter. Your wort will develop into the perfect pH to suit your yeast, it will even smell kind of like sourdough bread, and you will get more consistent results with finer product.

As the saying goes, all bourbon is whiskey, but not all whiskey is bourbon. The same can be true for sour mash: all sour mash is bourbon, but not all bourbon is sour mash. Bourbon is only made in the United States and has to be made of at least 51% corn and aged in charred oak barrels to be labeled as such. This new American single malt is intended to be an annual release, which will change in its composition and flavor profile each year. So with that said, let’s get to tasting this unusually mature, unusually complex take on American single malt whiskey. In 1964, the U.S. Congress recognized bourbon whiskey as a “distinctive product of the United States” and outlined the rules of the spirit (listed above) in Title 27 of the Code of Federal Regulations.

Adding the sour mash during the production process can vary depending on the distillery. Some choose to include the mash at the cooker stage. Others prefer to add the sour mash to the fermenters. Where Did Sour Mash Bourbon Originate? As early as the 17th century Peter Shaw advocated that English distillers acidify or their washes using the juice of lemons, tamarinds or oranges to improve the taste of the resultant spirit. The use of spent wash (called dunder) was commonplace in Jamaica around 1700 for rum production. By the 19th century dunder was prepared, infected with bacteria, wild yeasts and microflora, to create new congeners, amino acids and esters. It is entirely possible that this production process is the origin of the sour mash process. Benefits of the Sour Mash process This method collects low wines from the still after the beer or wort has been pumped into the chamber and then distilled. When beer is distilled on the grain, the remaining denatured remnants are called spent grain. Some distillers may add portions of this to a subsequent mash, although it is unclear if the dead yeast — which acts as a nutrient to the next generation of yeast — is preserved after the beer has been boiled and the alcoholic vapor collected. Introducing Lactobacillus Siphon off your beer and charge your still. Again, replace 3-3/4 gallons of water into your fermenter so your yeast doesn't die while you distill. Beginner's Guide to Bourbon and Tennessee Whiskey". pastemagazine.com . Retrieved September 23, 2018.

Another way to make bourbon is using the sweet mash method. Sour mash bourbon was invented to solve a problem: consistency. With the advancement of technology, other methods have been developed and tested. To use the sweet mash method, a distiller needs to cook the grains, add the yeast, and let them ferment. There's no mixing of prior batches using the sweet mash method. Some pictures here show the historical moment when Brown-Forman staff came together and revived Catherine’s recipe. Belle Meade Sour Mash Straight Bourbon Whiskey has a mash bill of 64% corn, 30% rye, and 6% malted barley. Once mashed, these grains are fermented with two different strains of yeast, a process that plays a big part in the whiskey’s balanced flavor. Distilled Spirits Council Industry Review, Distilled Spirits Council of the United States, February 4, 2014.Bourbon is made with grain mash. The mixture of grain mash typically combines barley, rye, corn, and wheat. During the mashing process, the grains are crushed together and opened. Once the crushing is complete, they add hot water to bring out the sugars. When this happens, the pH levels rise.