Heineken (Rotterdam) grists in 1942

Over at the grist, the big change is the arrival of sugar. Rather a lot of it, amounting to almost 30% of the total. It was used in a rather odd way, however. Rather than just being added to the wort during the boil, it seems to have been fermented separately and then blended with the wort post-fermentation. For each brew there are two entries in record, one for the standard wort and another for a sugar brew. Both had the same gravities.

Otherwise, the elements remain the same: pilsner malt as base, backed up by kleurmout, broeimout and caramelmout. There has been a change in the proportions, however, with the darker beers containing far more kleurmout than previously. Doubtless to maintain the required dark colour in a wort which is not only much weaker, but also contains a large amount of sugar. The proportions of broeimout and caramelmout have also been modified, with less of the former and more of the latter. Not sure what the motivation behind that change might have been.

Another modification is the addition of kleurmout to the pale beers. Obviously, again for colour-correction purposes.

Heineken (Rotterdam) grists in 1942
Date	Beer	Style	pilsner malt	Kleur-mout	broei-mout	Caramel-mout	sugar
26th Jun	Li	Licht Lagerbier	70.00%	1.88%			28.13%
26th Jun	Beiersche	Münchener	49.69%	10.94%	5.63%	5.63%	28.13%
29th Jun	Do	Donker Lagerbier	49.69%	10.94%	5.63%	5.63%	28.13%
28th Jun	P dun	Pils	68.75%	3.13%			28.13%
1st Jul	P	Pils	69.37%	0.90%			29.73%
Source:
Heineken brewing record held at the Amsterdamse Stadsarchief, document number 834 - 1760.