RSS

Category Archives: Uncategorized

The Perfect Malt?

I recently read an interesting research article pointed out to me by Bleepbloop, thanks Bleepbloop! The article is from China and published in the Wiley Online Library by The Institute of Brewing and Distilling. The title is a doozy: “Optimization of kilning progress for equilibrating multiple parameters that strictly affect malt flavour and sensory evaluation” The researchers objective was to determine what times and temperatures create the “perfect malt”. Unfortunately, to read the whole thing you have to rent it for $6 but you can get the main idea from the summary.

In their experiments they measured the levels of  positive and negative flavour compounds in relation to drying times (referred to as withering time in the article) and curing time and temperature. The compounds they were measuring were lipid oxydation or LOX activity, nonenal potential, TBZ (content of carbonyl compounds) methional, furfural, hexanol and phenylacetaldehyde. All of which I believe contribute to either stale or cardboard flavours. They also measured levels of H-hydroxy-2,5-dimethyl-3(2H) or HDMF which is the main contributor to sweetness and malty aroma. As well malt samples were given a sensory score rated by 7 professional sensory panellists from the Tsingtao Brewery

After plotting their data they’ve concluded that the ideal drying time is 14 hours: 1 hr at 45C, 5 hrs. at 55C, 5 hrs. at 65C, 3 hrs at 76C, 50% re-used air at 76C. Note: given the high temperatures I’m assuming that these would be the kiln temperatures below the bed or the “air-on” temperatures. Curing temperature is 86.35C for 3.19 hours.

Most of the article describes their methodology and what kind of testing was used for each flavour compound and it doesn’t go into that much detail about the effects of each compound. They also specify that these results would be different for different varieties of barley. The variety they were using was Gairdner barley grown in Australia. There is a lot of information in this article I don’t understand but the conclusion is interesting. I wish they had included the malt temperature during the kilning because without it, it’s impossible to replicate exactly. I do wonder how detectable these flavours are and at what point are they noticeable? The curing temperatures tested ranged from 84C to 90C, curing times ranges from 2.5-3.5 hours and drying times measured ranged from 10-14 hours. Not a wide range at all, in fact, they kind of seem on the low end of the scale. Unfortunately, there was no mention of diastatic power in the article as the study just focussed on flavour and there was no mention of moisture contents. I also find it strange that they did not include the kilning schedules for the 10 and 12 hour kilned malts. Are we to assume that the temperature increases coincided with the same moisture contents in each sample? There seems to be some key information missing here that would have made this article more useful.

This research paper makes me wonder if “perfect” is something that is worth achieving or does this goal bring with it the risk of industrial uniformity. It still seems to me that there are enough variables involved that what is considered perfect is still subjective. Of course, it’s interesting to see what is at play when making malt and it’s good to know that  the levels of those flavour compounds that cause stale or cardboard flavours are measurable. However, I have never noticed these flavours in my malts so it’s not something I’ve ever worried about. I have tried this schedule with my barley, knowing that I couldn’t actually replicate their conditions without using the same equipment, and I found I needed another hour or two curing time to become more friable, meaning my malt was not dry enough. As it was, the roots were still a little flexible and hard to shake off. It would be interesting to see this same experiment done on a greater scale, that is with wider temperature and kilning time ranges. I’m sure for large scale maltsters this is a useful article but for myself I think I prefer variety, good or bad. The best beer I’ve ever had was the pale ale I made from the diastatic brown malt that was dried over fire, very far from scientifically “perfect” I’m sure but beyond perfect in my mind.

Advertisements
 
24 Comments

Posted by on December 2, 2016 in Uncategorized

 

Tags: , , , ,

Brumalt, Honey malt, Melanoidin malt Part 2

Comparing some malts

Comparing some malts

This malt has been a real challenge. I’ve tried to make it 10 times varying the process each time. My goal has been to make a malt that tastes like Honey malt. So far I’ve come close but not close enough. I wanted to re-do this one as well because a few people had asked me and I was wondering myself, what the difference was between Brumalt and a dark Munich or Aromatic malt.  I don’t have much information on Brumalt in the textbooks that I have so I’ve been doing this mostly by trial and error. I’ve been measuring my results with store bought malts (Honey and melanoidin) comparing pH, colour,  extract and flavour.

As you may know Honey malt is made by the Gambrinus malting company right here in my home province of British Columbia Canada so I had to ask if they would give me any information on how it’s made. They wouldn’t of course, the recipe is a closely guarded secret but they were nice enough to give me a tour of the plant which you can see here. Like the name says it tastes like honey but it’s a dark honey flavour and has an almost wine-like fermented quality to it.

Barley recently emptied from the steep tank to a Saladin box at Gambrinus Malting Ltd.

Barley recently emptied from the steep tank to a Saladin box at Gambrinus Malting Ltd.

The first thing I noticed when comparing malts is that store bought melanoidin and Honey malt have a lower pH than Aromatic malt or a Munich of a similar Lovibond. So what causes this low pH if it’s not the colour?

According to the descriptions I’ve read, after a 6 day germination the green brumalt is piled up and covered with a tarpaulin or if it’s made in a box system all ventillation is cut off and the malt heats up to as much as 50C due to respiration, usually within 24 hours. (Munich is only allowed to reach 25 C). Once enough carbon dioxide builds up the malt stops growing and cools down but the enzymes continue to develop which create a malt with a lot of “low molecular weight sugars and amino acids” (Kunz 2004 p.180)  In Malts and Malting, Briggs states that this phase lasts 30-40 hours (Briggs 1998 p. 714) Kunz states 36 hours.

A few more details in Brewing and Malting include a moisture content of 48% and an increase in temperature during the last 36 hours of germination to 40-50C. Sometimes heat was added “…with a low flame”  Kunz also states “Melanoidin malt… contributes, by virtue of it’s low pH to flavour stability…” (Kunz 2004 p. 180)

In Jean DeClercks A Textbook of Brewing he describes the practice of “Thickening the Piece” “…used for the preparation of malts with a rich aroma. It simply consists of making the piece into a thick heap on the last two days of flooring. The temperature rises to 50C and enzymatic activity becomes very intense. Pre-formed sugars are formed in large amounts and there is considerable proteolysis.” (DeClerck 1957 p.177) Something else jumped out at me in the DeClerck text when he described an investigation carried out by Luers and Gottschneider on the effects of different proportions of CO2 on malting. With 20% CO2 in the air during germination the presence of ethanol was detected. (DeClerck 1957 p 175) Is this why I’m detecting a wine-like fermented flavour and aroma from Honey malt?

A while ago I made an acid malt by placing green malt into a sealed ziploc bag keeping it warm at 35-40C for 36 hours.  The ideal environment to promote the growth of Lactobacillus bacteria which is naturally present on the husks, is at 37C in an anaerobic environment.  So it makes sense that some amount of acidification is happening during this couching phase of the brumalt process.

In order to mimic these natural occurrences on a small scale I had to enclose the malt in a ziploc bag to seal out the oxygen. I then added some heat to keep the temperature at 37C This worked well and I was able to get a malt with the pH at the same level as Honey malt after 16 hours at 37C before raising the temperature to 50C to stew. But I wanted to see if I could make it in a way that was closer to the descriptions.  I tried it once in a small cooler loosely covered and the temperature rose to 42C due to respiration, but it took three days and I was concerned that the malt would overgrow. When this happens the malt will taste bitter and sprouty. I then bagged the grain for a period to acidify it just like before but this time it didn’t work. After kilning the pH was not lower, I thought that perhaps the hot couching may have killed off the  bacteria.

Honey malt left, my brumalt center, batch #7 on right. 18 hr stew at 50C vs 8 hr.

Honey malt left, my brumalt center, batch #7 on right. 18 hr stew at 50C vs 8 hr.

PH is also affected by colour of course, generally speaking the darker the malt the lower the pH, but a characteristic of Honey malt is that it lacks the roasted or toasty flavours you would get from a dark malt due to the lower curing temperature. The colour comes from the melanoidins developed during stewing.  When you add a stewing phase at  50C 122F proteolytic enzymes break down the proteins into sugars and amino acids which when combined with heat in a moist environment create melanoidins which give you malty flavours and colour. You can control the amount of colour by varying the time your malt spends at this stewing phase. After experimenting I found that 8 hours at 50C will give me a colour around 25-30 L, similar to Honey malt. Of course that will vary with the barley used and the amount of protein in the grain. Roasted malts on the other hand which are created when the malt is dry and at a higher temperature will give you more roasted flavours, sort of like the formation of toast vs. bread crust.

DSC02148

Comparing pH of my brumalt to Honey malt – just pure luck that they’re exactly the same, other batches are not.

DSC02150One test that I’ve been using to compare malts is meant to measure the soluble sugar and extract potential (sort of). It’s not a scientific test and not very consistent but since it’s just comparative it does give some insight as to how a malt is made. I’ve been using this test because it’s quick. A measured amount of grain (1.6 oz) is weighed and crushed and mixed with 250 mL of boiling water. The use of boiling water was meant to inactivate the enzymes but since the temperature of the water drops as it’s added to the sample some of the enzymes  survive and end up converting some of the starches.The sample is allowed to settle and cool and then is measured with a refractometer.

In a true cold water extract test the water is mixed with a solution of ammonia to inactivate the enzymes. Cold water extracts are used to measure the amount of soluble sugars or “pre-formed sugars” there are, which tells you how well modified a malt is, the higher the number the more thorough the modification.

The results that I’ve gotten just using boiling water are quite telling. Honey malt gets a very high brix number similar to a pale malt that I made. My Brumalt was a close second, Munich scored lower and caramel malt scores very low.  So since this test is actually showing us the diastatic power or even the extract potential it would lead me to believe that honey malt is kilned at lower temperature than Munich. Keeping the kilning temperature below 50C until the moisture content is below 10% will not destroy as many enzymes.

In a true hot water extract test the malt is mashed according to a very specific schedule and what you find out is the potential extract of a malt.  I tried my own version of this test as well with small 50g samples comparing Honey malt, Munich 30L, Aromatic, Melanoidin and my own. Although my test was crudely done Honey malt still came out on top with the highest brix reading, mine was still second. 

Here are some of the things I’ve tried with these these test batches:

Germination temperatures, 1. warm throughout, 2. warm during the last 3 days and 3. warm for the last day only.  Warm germination temperatures during the final phase of germination promote the development of proteolytic enzymes, the enzymes which act on proteins. From what I’ve read the longer the germination the more enzymes will develop and to have a long germination the temperature must be kept at 13C or 55F.  The warmer the germination the faster the grain grows. What seems to work best (for my barley) is 6 days at 13 then a day at 22C.

Couching, I’ve tried a few different lengths of time to get a lower pH and determined that with my barley, 16 hours at 37C with a shorter rest at 50C for 8 hrs, both in a sealed ziploc bag and low kilning temperatures  gives me the same pH and colour.

High kilning- raising the temperature to 60C while there is still 25-30% moisture. Usually done with Munich malt for maltier flavour and for colour, this will lower the diastatic power of the malt. I don’t seem to be having any problems achieving colour with kilning temperatures below 50C, the amount of colour is dependant of the length of time it spends stewing at 50C. This could be an indicator of a high level of protein in my barley. So I settled on using low kilning temperatures to maintain the enzymatic power as much as possible.  As well I’ve also tried different curing temperatures and I’ve found to minimize the roasty character the curing temperature must be kept below 200F. The biggest changes in colour and pH occur during the curing phase, a half hour can make a huge difference.

What I’ve achieved so far is a sweet malt, not roasty and with the same pH and colour as Honey malt. It’s very unique and I’ll be using it whenever a recipe calls for melanoidin malt but it has more of a tart flavour and is missing the deep honey-like and almost vinous flavour characteristic in Honey malt. I am not going to give up trying to figure out this malt but there are a lot of variables at every stage. Along with my procedure, the variety of barley and it’s protein content could be affecting my results as well as the scale at which it’s produced. As well since bacteria seem to be involved it’s flavour characteristics could be due to the local environment in which it is malted or where the barley was grown which is literally 1000 km away. Unfortunately I have to put this malt on hold since I’ve used almost all of the barley I grew last year. This is the schedule that comes closest so far:

This will give you a sweet yet sour malt (low pH) that’s around 30L and maintains it’s diastatic power.

Steep until 48%

Germinate at least 6 days at 13C, acrospires at 3/4  then 24 at room temp. 22C (acrospires on average are now the full length of grain)

Couch (lactic acidification phase) in a zip-loc bag sealed for 16 hours at 37C

ramp up temp to 50C (proteolysis phase) and hold for 8-10 hours for about a 30L colour, Add more time for more colour 16-18 hrs = around 60L

Kiln at 40-45C for 24 hours or until moisture is below 10%

Cure:

1 hour at 175F  79C

1 hour at 185F  85C

3 hours at 190C  88C

 

 

 

 

 
 

Tags: , , , , , , , , , ,

Garden update May 1st 2015

Looking pretty good so far. I’ve rigged up the chicken wire like last year to prevent lodging. It worked well last year, this time I’ve added a little more support with a bamboo cross bar in the middle to keep the centre up. Check out the video:

 
Leave a comment

Posted by on May 5, 2015 in Uncategorized

 

Put this on your christmas list!

Last Thursday night I got to go to a presentation by renowned beer historian Ron Pattinson who was in Vancouver promoting his book The Homebrewers Guide to Vintage Beer. Chances are if you’re reading my blog you’re interested in all things beer and already know who Ron Pattinson is. If you don’t, get the heck off my blog right now!  Go to Shut Up About Barclay Perkins for some serious reading – then come back to my blog. The event was organized by Vanbrewers and took place at the Cobalt on Main street. The focus of the talk and the book was on historical english beers and many of the facts were quite surprising to me. I had no idea that English brewers used invert sugar to such an extent and often used caramel to adjust colour. He also eplained that the purpose of the parti-gyle method of brewing was for efficiency and to allow the brewers to be able to blend the different worts in order to acheive a consistent starting gravity for every brew. Another surprising fact was the use of attemperators (which sound like large scale immersion chillers) to control the temperature of fermenting beer during the 18th century. The book is full of recipes from 1804 to 1955 based on the actual brewing records of the breweries and are all scaled down for home brewers. I can’t wait to try some of them! Of course I got him to sign my copy – it says “Hope you make nice porters with your diastatic brown malt” How cool is that?DSCN1084

 
6 Comments

Posted by on November 15, 2014 in Uncategorized

 

Smoked Pumpkin Dubbel

In the most recent edition of Brew Your Own magazine was an article on making a smoked pumpkin Saison which sounded pretty awesome. I already had some belgian yeast (Wyeast Belgian Ardennes) as I was planning to make a Dubbel before I read the article. So I thought why not add smoked pumpkin to my best dubbel recipe. The only thing I’ve grown here is the pumpkin but I figured I ought to make a brew day video since I haven’t made one yet. Something I didn’t account for was the amount of sugar in the pumpkins. The pre-boil gravity was 1.083 so I added some water to make it 1.07. I also tried to malt some of my pumpkin seeds but none of them sprouted, perhaps it’s too soon after harvesting them, I’ll try again in a few months. For this brew I did a single step mash at 152 F for an hour but half way through I pulled off about a gallon of thick mash, boiled it and added it back to the main mash to maintain the temperature as it had dropped a few degrees. So I guess it’s a single decoction mash.

 
Leave a comment

Posted by on October 12, 2012 in Uncategorized

 

Tags: , , , , ,

 
The Meandering Meadery

Cultivating fermented food and drinks one jar at a time

Sprowt

Home Malting Equipment for the Home Brewer

Brülosophy

They Who Drink Beer Will Think Beer

Immaculate Brewery

Growing, malting and brewing beer

Creative Brewing

by Scott Ickes

A Brewer's Wife

Law librarian, brewer's wife and mom of three girls (not necessarily in that order)

From Plants to Beer

The real route of beer

My Own Home Brew

My record and experience in brewing

F Words I Love

Fresh. Frugal. Fermented. Free.

Romping & Nguyening

Romping around the world and Nguyening since March 2014.

Brewing Beer The Hard Way

Growing, malting and brewing beer

Five Blades Brewing

F' Everything, We're Doing Five Blades

The Jax Beer Guy

This Guy Knows Beer -- Also visit www.JaxBeerGuy.com

East Happyland Homebrew Garden Louisiana

Gardening hops, grains, vegetables, and brewing beer in South Louisiana. And they said it couldn't be done....

Bergfast bryggeri

Et lite kjellerbryggeri blir til

The Apartment Homebrewer

Brewing small batches of craft beer in a 650 sqft apartment

Redneck Brewing

Because good beer doesn't require sophistication.

Bishop's Beer Blog

Just another WordPress.com site

The Quest for Edelstoff

Making Liquid Bread