Maltose-negative fermentation

What is actually happening

Saccharomycodes ludwigii and similar yeasts consume glucose and fructose but not maltose, which is the dominant sugar in wort. They therefore produce carbonation and some fermentation character while leaving most of the extract untouched.

The trade-off is the same residual sweetness as arrested fermentation, which is why it is increasingly combined with other techniques rather than used alone.

Styles where this step is decisive

• Alcohol-free pale lager0–0.5% ABV

  A pale lager produced at or near zero alcohol, now the largest and most refined part of the no-alcohol category.

• Alcohol-free IPA0–0.5% ABV

  An alcohol-free beer built around heavy dry hopping, since hop aroma is added after fermentation and survives the process intact.

• Alcohol-free wheat beer0–0.5% ABV

  An alcohol-free wheat beer — often the most convincing of the category, because wheat body and yeast esters survive dealcoholisation well.

Related steps and concepts

• Arrested fermentation — The related approach.
• Maltose-negative yeast — The organism.