Monday, December 21, 2009

Clear Sugar Experiment - Bottling

Over the weekend I bottled the "Clear" Sugar Experiment that I posted about last week.  Sunday I wanted to brew a Belgian Strong Dark based on De Struise Pannepot, and I needed the yeast harvested from the experiment to pitch into it.  The experimental beers had hit a gravity around 1.006 (~90% AA) and they looked clear, so I didn't think it was necessary for them to sit longer than two weeks in primary.

The experimental sugars were used for the priming dosage for their respective batches.  I haven't done this two previous sugar experiments, but when we are talking such minute differences, the extra work seemed worth it.  I weighed out the sugars based on how much would be needed to give the equivalent carbonation of 1 oz (28 g) of sucrose.  This worked out to: 28 g of table sugar, 28 g of clear candi rocks, 39 g clear candi syrup, and 33 g of corn sugar.  Finally for the batch that received no sugar I went with 46 g of DME, just to keep it completely sugar free.  I am a bit concerned that priming in this way could induce some variability if I didn't work things out exactly right, but it seemed worth doing since the amount of sugar added for carbonation is equivalent to 28% of the sugar added to the wort initially.

After the sugars were weighed out, I dissolved them in enough water to make ~10 tbls of liquid.  Each glass got two minutes in the microwave to dissolve the sugars and make sure everything was sanitary (as usual the candi rocks were the biggest pain to get dissolved).

Each sweet syrup had enough sugar to carbonate 120 oz of beer to 3 volumes of CO2 (assuming I did my math correctly). Since each contained 10 tbls of liquid this means that 1 tbls would be enough to carbonate 12 oz of beer (convenient how that worked out).  So I used a tablespoon and funnel to dose all of the bottles with the sugar solution (2 tbls in each bomber).

Next I siphoned directly from the five jugs into the bottles (a Mini Auto-siphon is a must if you want to do something like this since it fits into the mouth of 1 gallon jugs), and capped them.  The yield was a perfectly even two bombers and five 12 oz bottles per jug (just over 4 gallons total). The small amount of leftover beer tasted pretty good (fruity, clean pils malt, hint of hops etc...), if still a bit yeasty. 

I'm looking forward to a full blind taste test on these in a couple weeks.


Lee said...

I'm not sure the candi sugar will behave the same. The sugar part of clear candi sugar is just sucrose, but it's got a higher water content per weight. According to BeerSmith, Clear Candi sugar has 36 points per pound per gallon, while table sugar has 46ppg. I think it'll end up being a little undercarbonated. I can't think of any references to this off the top of my head though I know they talk about this on the Ommegang/Randy Thiel episode of the Brewing Network in 2007 when he explains why he doesn't use clear rock sugar.

On the other hand, corn sugar has the same ppg, but since it's dextrose (monosacharide basically glucose) instead of sucrose (disachharide of glucose and fructose), I think it provides slightly more CO2 as it doesn't require energy to break down the disacharide. I don't know as much about that. I think palmer explains it pretty well if I remember correctly.

The Mad Fermentationist (Mike) said...

As far as I am aware sucrose gives more gravity and CO2 than glucose because it gets a water molecule added onto it as part of the fermentation process (C12H22O11 + H2O → 4 CH3CH2OH + 4 CO2 ). Most priming sugar calculations suggest using 15% less sucrose than glucose for the same amount of carbonation.

As for the candi sugar as far as I was aware it is nearly 100% sucrose, although I certainly could be wrong (I didn’t check the gravity numbers as part of the experiment). It would be hard for it to be more than a tiny bit water because it is so hard, more water and it would be at a softer candy making stage (softball, thread etc…). This chart ( ) suggests that the hard crack stage isn’t reached until 99% of the water is removed from the sugar.

Lee said...

I could be wrong, but I've heard that from multiple sources. Table sugar is mostly pure sugar, candi sugar crystals are Sugar/Water crystals. I've consistently read that it gets a lower ppg than table sugar. An easy way to test would be disolve an equal weight in water and just use a hydrometer to measure it (or probably a Brix refractometer). In the BN podcast Randy Thiels says that didn't like using rock sugar because of the high water content (infact makes it prone to mold) resulting in inconsistent yield. He infact calls it "sucrose with extra water content. Also it was a pain to disolve and he got no flavor difference from corn sugar or sucrose. (Sunday Session, 5/20/2007 around 1:04:00 or so).

You're partially right about the difference between sucrose and dextrose. Forgive me if this is technical. As far as adding the water, that wouldn't cost any energy. Hydrolysis of a glycolytic bond is an exergonic reaction (energetically favorable, gives off energy) and just needs a catalyist (sucrase enzyme) to bring it about. It becomes higher yield than dextrose, because the same amount of energy yielding sugar has a molecular weight of 340 as a disacharide and 360 as a monosacharide. However, that's only a 5% difference in weight, but there's a 15% difference in CO2 generation ( Since CO2 generation is directly proportional to the amount of fermentation, I was guessing that it was a difference in fermentability of fruc and gluc. However, reviewing my bochem text, they yield the same amount of EtOH and CO2, so I bet it's because there is some water in the dextrose crystals, making them even heavier than they should be (and thus lower yield). This would suggest that BeerSmith is wrong that both have the same ppg, and we should also do the hydrometer/refractometer test on them!

The Mad Fermentationist (Mike) said...

Using my scale, measuring cup, and hydrometer, 1 ounce of candi or table sugar dissolved in tap water to make 8 oz of sugar solution yielded an identical gravity (1.040 @75 F, 1.042 adjusted). Which is pretty much spot on (1.045) considering my hydrometer reads pure water at ~.997, but they are the same which is really the only thing that matters here. Feel free to repeat the test yourself, but that is good enough for me to call candi sugar "essentially" 100% sucrose.

I don't have any more corn sugar on hand, so I can't test that one.

Lee said...

I guess you can't trust everything you hear/read! Thanks for figuring it out for everyone!

The Mad Fermentationist (Mike) said...

I wonder if different brands are made in different ways, might be that some contain a bit of water, and some do not.

It will also be interesting to see if the flavors, in addition to the gravities, are identical.

Lee said...

The amount of sugar you're using amounts to just over .25#/5gallons. I'm interested to see how much flavor you get there, and how that would compare to adding the syrups to the primary fermentation after a couple days (as you probably can't boil them all in separate pots and keep them the same).

The Mad Fermentationist (Mike) said...

I am expecting the sugars added for priming to have a very minor impact on the overall flavor of the beer. 4-5 oz in 5 gallons is pretty standard for priming, but you are right that doesn't sound like much from a flavor stand point (particuarly for such light sugars) that doesn't sound like much.

So far the few sample bottles I have opened have all had pretty good carbonation, although one had quite a bit of sulfur going on (which will hopefully fade).