Thursday, 30 October 2014

German brewing in 1966 - malting

Now we've got barley out of the way we can turn to the business of turning it into malt.

First some general stuff:

"Many German breweries, particularly in the south, have their own maltings. The increasing demand is being filled by existing commercial maltings.

The five-day week has forced maltings to adjust to a 7-day germination period, and malting methods must be adjusted accordingly. A germination period of 8-9 days was normal some years ago and for dark malts it was even longer. However, as a day was usually lost after casting the steep before the barley began to grow, we really only had a 7-day germination period in an 8-day malting period."
Journal of the Institute of Brewing, Volume 72, Issue 1, January-February 1966, page 15.

Narziss keeps moaning about the trouble the introduction of a 5-day, 40-hour working week. As if it were the work of the devil.

I think it's much rarer now for German breweries to have their own maltings, as in the UK. Come to think of it, about the only place I can think of where this does still happen is the Czech Republic. In the 19th century all the famous Burton and Edinburgh brewers had their own maltings. This was understandable as they specialised in Pale Ales, beers where the quality and colour off the malt was paramount. But gradually they moved over to buying in all their malt during the first half of the 20th century. Presumably because it was of reliable quality.

Now steeping:

"Steeping.—As a result of a fundamental change in the concept of steeping, we have achieved a position whereby a well-modified, completely satisfactory malt can be produced in a 7-day germination period. A shorter steeping period is now possible by making use of methods such as warm-water steeping (14-18° C), frequent dry steeping, periodic removal of CO2 by suction, sprinkling of the steeped barley, and re-circulation of the barley two or three times during the steeping period. By means of these methods less damage is done to the barley and the steep is cast with the barley visibly germinating and even at times showing two or three rootlets. This results in increased utilization of the germination plant. With warm-water steeping, it is essential to maintain an even temperature throughout; the steep room has to be controlled accordingly and, when using higher temperatures, a punctual CO2 removal must be carried out, preferably controlled by a clock. If cold air is sucked into the steep this will result in delayed water absorption and uneven germination."
Journal of the Institute of Brewing, Volume 72, Issue 1, January-February 1966, page 15.

Steeping was a huge deal in Britain when malt was taxed. Because it was taxed on the volume when it came out of steeping. As this could be manipulated through the moisture content, there were strict rules about what, and for how long, maltsters were allowed to do.

I haven't the foggiest idea of steeping temperatures, so I looked it up in a modern British brewing manual. Here's what it says:

"The steep-water temperature should be controlled. At elevated temperatures water uptake is faster but microbial growth is accelerated and the grain may be damaged or killed. The best temperature for steeping immature (partly dormant) grain is low (about 12 ºC, 53.6 ºF). For less dormant grain a value of 16-18 ºC (60.8-64.4 ºF) is often used."
"Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, pages 14 - 15.

That seems pretty much in line with what Narziss derscribes. Briggs also describes CO2 extraction:

"Air rests are used between steeps. After a steep has been drained air, which should be humid and at the correct temperature, is sucked down through the grain. Such downward ventilation, or `CO2 extraction', assists drainage, provides the grain with oxygen, removes the growth-inhibiting carbon dioxide and removes some of the heat generated by the metabolizing grain. In consequence, and in contrast to traditional practice, barley leaving the steep has usually started to germinate."
"Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, page 15.

Now something about moisture content:

"A number of investigations have shown that a sufficient moisture content of the barley is absolutely essential. It is possible to reduce germination time even when a very high degree of steeping is used, provided steps are taken to avoid subsequent drying out of the barley. Formerly moisture contents of 45-46% were used only when steeping dark malts but now this level of moisture is not unusual even for pale malts. By improving the degree of steeping on the 1964 season barleys (which were of low extract and enzymically poor) results shown in Table I could be obtained."
Journal of the Institute of Brewing, Volume 72, Issue 1, January-February 1966, pages 15 - 16.

Why would you have a greater moisture content in dark malts?

Here's that table.

Effect of Steeping on Analysis

Degree of steeping

43% 46%
Moisture content 4.60% 4.80%
Extract (dry) 80.10% 80.80%
Coarse/fine grind difference 2.70% 1.70%
Protein content 11.90% 11.70%
Degree of protein modification 33.80% 35.40%
Colour (E.B.C.) 2.2 2
Conversion (min.) 10.15 10.15
Malting loss 9.50% 12.70%
Germination loss 4.70% 4.10%
Steeping time (hr.) 62 74

Want to know how British malt compares? Briggs reckons the dry extract of pale malt is 77-83%*. The German malt is smack in the middle of that range. For darker British malts the extract was lower, 75-78%**. Briggs states that malting losses account to 6.5% - 14%, but breaks them down differently to Narziss:

"Malting losses can be defined in several ways. If they are defined in terms of the losses in dry weight, which occur when cleaned barley entering the steep is recovered as kilned malt and has been de-culmed (dressed), then the losses sustained in making conventional malts are usually in the ranges: steeping losses, 0.5 - 1.5%; germination losses, 3.5 - 7.5%; rootlets, 2.5 - 5.0%. These divisions are artificial, since some respiration and growth occur in the steeping phase and in the initial stages of kilning."
"Brewing: science and practice", by Dennis E. Briggs, Chris A. Boulton, Peter A. Brookes and Roger Stevens, 2004, page 17.

That leaves the German losses right at the top end, or a little beyond, of the British range.

More about malting and malts next time.

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