dunder

dunder is a Jamaican rum term for leftover liquid after distilling a batch of rum; its use in sugar cane fermentation creates a “high ester” rum and differentiates such rums from all others. Advocates see it as an integral component to the development of the powerful character and even “hogo” aromas of traditional rum from Jamaica and other Caribbean Islands. Described in the texts as “spent lees” from the stills (stillage), it might historically have encompassed virtually all leftovers from a finished distillation, whether from the still or from one or both retorts, where those are part of a still’s architecture.

Dunder was demonstrably utilized since the eighteenth century in Jamaica and the Windward Islands (historically comprising Martinique, St. Lucia, St. Vincent, the Grenadines and Grenada), with the accepted understanding that (as Bryan Edwards wrote in 1794) it was “of the same use in the making of rum, as yeast in the fermentation of flour… . [it] causes the sweets [i.e., skimmings and molasses], with which it is combined, to yield far more spirit than can be procured without its assistance.” In the mid-nineteenth century Whitehouse and others identified its ability to alter not only yields but also flavors, aromas, and other fundamental characteristics.

Jamaica traditionally used greater portions of dunder and skimmings (or scummings, froth and residue removed from sugar boilers) than any other rum producing island. Whereas Colonel Martin describes Windward Island fermenters being filled with roughly one-third each water, scummings, and dunder; Edwards describes the Jamaican recipe as being 50 percent dunder, 36 percent scummings, 6 percent molasses, and 12 percent water.

Dunder’s utilization by Jamaican distillers required storage, giving rise to the mythology surrounding muck pits, holes in the ground where dunder was left to fester and grow bacteria before being used (in fact, only a small amount of the dunder, the heaviest part, goes into the pit; the rest is stored in normal casks or tanks). Eric Seed, who revived the nineteenth-century brand Smith & Cross, believes that “the dunder/skimmings or ‘muck,’ if you will, are as indispensable as the ambient yeast, and the pot-still process.”

The term “muck pit” is also historical; it has referred to any dump of organic waste and reflects farmers’ use of natural bacteria to break down organic materials for further use. Today Jamaican muck pits are few or at least elusive, and mythology has sprung up around them, with apocryphal tales of animal carcasses thrown in to add flavor. As the surviving pit at the Hampden distillery demonstrates, such things are not needed: bacterial transformation of spent molasses and distillation lees (Clostridium butyricum are two that often occur) has been shown to create high esteric content and to provide greater complexity and even hogo to rum when a small amount of muck from the pit is added to the fermenters.*