Malt musings

Malting is a fundamental procedure in whisky making, the process of converting starches in raw barley into fermentable sugars. That’s achieved by forcing then abruptly halting germination, to produce what we know as malt, which can then be used in a mash of water and yeast to produce alcohol without the requirement of any exogenous enzymes.

We can’t be sure where or when malting specifically for whisky first occurred. Indeed in his 1913 work The Manufacture of Whisky and Plain Spirit, the ‘Great Documenter’ JA Nettleton scarcely covers the history of the subject, stating only that: “The ordinary routine of floor-malting is so well known that it is unnecessary here to follow all the details of such work, but all prominent and interesting points will be referred to.”

However, Nettleton does give a description of the workings of the floor maltings, close to the procedures that you will hear recited on tours in the few remaining facilities today. Fresh barley is received at the distillery. It is then screened, graded and cleaned, to remove dirt, broken corns and seeds. When required it is washed, loaded in tanks and steeped, allowing space for a 25 per cent swell in the seeds as they absorb moisture.

The damp barley is then spread evenly onto the malt floor, again allowing for a swell of up to double its original size. To guarantee a more uniform product, the barley is regularly turned by hand while it germinates in an environment with controlled humidity and temperature.

The germinated barleycorn is now moved to the kiln for drying. It is raked while being heated from below. A throughflow of air is essential to dissipate any moisture or “peat reek” in the atmosphere.

PATHS TO FLAVOUR AND PROFIT

Almost paradoxically, today there is a huge trend towards exploring and celebrating historical bottlings. Whisky enthusiasts wax lyrical about superior flavour integration, texture, and more recognisable distillery character in whiskies from the past, inevitably concluding that “the old methods are the best”.

The secondary market is booming, whisky auctions are thriving and fresh competition appears regularly. Similarly, distilleries are now looking for points of interest and individuality, working with distillers who are more than aware of historical processes, how they’ve changed and how those changes may have affected the flavour of the whisky.

Research at organisations such as the Institute of Brewing and Distilling (IBD) and the Scotch Whisky Research Institute (SWRI) is being funded from all ends of the industry, and flavour-based learning is becoming a priority.

Pair that with the fact that single malt Scotch whisky is now consumed all over the world, and the need for efficient production is as great as ever. It would appear that we find ourselves at something of a historical crossroads, and the future of whisky could well lie somewhere along the “flavour-profit” spectrum.

MALT SCIENCE

The Scotch Malt Whisky Society’s spirit educator Dr Andy Forrester says: “Although alcohol yield is always a consideration, there has been a huge shift to flavour-based learning within distilleries since the turn of the century. In malting, compounds are present in the grain or are produced during germination that may become flavour active through reaction with others, later in the process. Strecker aldehydes, for example, may be responsible for oily-grassy characteristics, and are produced by the reaction between amino acids and sugars.

“Kilning not only imparts medicinal, burnt, smoky flavours associated with peat smoke, but also gives rise to sweet, malty, biscuity notes. And increased temperatures can be controlled to encourage Maillard reactions that can produce fruity, peachy, cereal, roasty, toasty coffee, cocoa qualities.”