Flat beer with table sugar?

Question

I brewed this Ale Oktoberfest beer and I thought everything went perfectly, but the bottles are flat (have tried 4 of them)

Some details:

• 2 weeks in the primary
• 1 week in secondary (5 gal carboy)
• FG of 1.012
• Priming solution: boiled & cooled solution of 5 oz. table sugar, mixed well into bottling bucket.

The bottles have sat for 3 weeks. They started out at over 70 but lately it has been cooler and they have been around 65 degrees.

I asked my homebrew shop and they said the problem is likely that I used table sugar instead of corn sugar. They said that disaccharides are harder to break down than straight glucose and maybe the yeast just couldn't do it.

However, looking online it seems lots of people use table sugar. This is my second batch, for my first batch I also used table sugar and it had perfect carbonation.

Here are all the possible problems that I can imagine:

1. Too much yeast dropped out after secondary fermentation, so not enough was left in suspension to carbonate? (counterpoint: 3 weeks is not very long, if anything it's on the shorter side)
2. Maybe they indeed had trouble with the disaccharide sugar (or maybe combination of 1 and 2)
3. During my first batch I used vegan sugar from Whole Foods, my second batch I used Domino sugar
4. I pitched the yeast a little warm (80-85 degrees). But the bottles have mostly been conditioning around 65. Maybe fermentation encouraged the growth of more yeast that preferred the warmer temp, and they don't like the cooler bottling temp.

Possible solutions:

1. Bring bottles up to 70 degrees, wait longer
2. Pour everything into bottling bucket, add CBC yeast and 5 oz. corn sugar solution, rebottle. (Problem with this: if the initial priming sugar was never fermented, would this create bottle bombs once healthy yeast is re-introduced? Would the priming sugar cause a measurable change in gravity, so that I could measure whether it fermented?)

Any other advice or thoughts?

Update

I have a few more data points:

• I tried more bottles: some have a tiny amount of fizz, others practically flat.
• Immediately after bottling, 4 bottles went down to Virginia. When they were opened, they were all carbonated, with a head even.

I performed the following experiment:

• I opened two 22 oz. bottles and added 1/4 tsp CBC yeast rehydrated in 1 1/2 tsp water
• To one of these bottles I also added a solution of 3/4 tsp corn sugar

One week later, both were carbonated. The one with sugar more than the other, and maybe a tad overcarbonated but not by much.

I plan to add the same amount of yeast and 1/2 tsp corn sugar to the remaining bottles.

Thank you everyone for your help and suggestions. I'm not sure if there is one answer I can accept but I will read through them again and see.

Update #2

Here I was ready to add a yeast / sugar solution to each bottle. It has now been 7 weeks in the bottle and I last tried one maybe 2 weeks ago and was still pretty much flat.

I opened 7 bottles to re-yeast, all of them were carbonated. SMH.

Answer 1

It's probably just too cool. I had lots of problems with carbonation when I left my bottles in my 65-70 degree basement. In fact, I had one batch where the bottles on the concrete floor did not carbonate but the ones sitting on top of those, off the floor, did carbonate. Eventually, I started putting them in the laundry room on a shelf above the dryer, where it's in the mid-eighties, and everything carbonated fine after that.

Answer 2

If you saw a beer head during the 2nd fermentation, you likely just let the beer get too cold. Ales tend to like 70F+ bottle fermenting conditions.

You can tell if your beer's yeast has died by the foam created when mixing in sugar. The reaction will always create alcohol and CO2. The reaction creates bubbles, which make the foam during fermentation. No bubbles = no yeast.

I doubt using table sugar is the problem. I have no idea why home-brew shops tend to universally disdain table sugar (except to up-sell you the expensive fermenting sugar). I have always used table sugar bought from Wal-mart and never experienced any problems.

In summary, you can either

1. Keep the beers in a slightly warmer place.

2. Make Lagers, which ferment a little colder.

3. Your homebrew store will sell carbonation pills you can add to your bottles, but you'll have to open and reseal each of them to do this, your mileage may (and likely will) vary.

Edits to clarify questions about fermenation process, and better explain what to expect

Answer 3

Ehhhh, not having 50 points... Either way, I would HIGHLY recommend not opening up the bottles and adding anything, or taking anything else out. This is just asking for contamination or at least oxygenation. Warm the bottles up a bit should work. Or letting them sit longer works too.

Also, the yeast that is left in suspension when bottling is normally the strongest/most hyper yeasts from your brew. They should be fine with a little cooler temperatures, higher abv, etc.

Answer 4

You can always leave them longer at the lower temperature, or bring them up to 70ish. Which Yeast did you use specifically? Did you re-pitch yeast during bottling or it was warm for the initial pitch? 80-85 is pretty warm for Ale Yeasts. Wouldn't kill it, but might give off some flavors that aren't wanted. Prior to bottling were you still getting bubbles coming through the airlock?

I don't do much homebrewing since brewing professionally for 5+ years in the San Diego Craft Brewing Industry. But I still have plenty of knowledge of brewing in general.

Answer 5

It might be that your beer is quite strong (you didn't mention the OG), and the yeast has bowed out. (what yeast did you use?)

What's the current reading on the brew?

I'd open up a couple of bottles, add a few crumbs of dehydrated yeast with a high alcohol tolerance (at this stage, using champagne yeast is quite ok, try it on a few bottles). Close it up again, put in a warm spot for a week, then cool it in the fridge for a day or two and open it to test.

I would not remove the beer from the bottles, it only oxidises the beer and introduces infections (plus extra work).

Also don't feed it more sugar unless you are sure it really needs it, exploding bottles are no fun.

FWIW, the only difference I can tell between cane sugar / beet sugar and brewing sugar is that cane or beet tastes most 'citrussi'.

EDIT: (to keep Stackexchange ettiquette happy):

Re: aerating, shaking the beer or water isn't all that effective, but if you get a fish tank air pump (with a little air filter, although I've used it w/o it and had no problems) and tie a weight to the 3mm tube that comes with it so it stays at the bottom, leaving this on over night starts the fermentation pretty quickly, probably because the wort gets moved around by the bubbles and the yeasts don't get stuck in areas they already munched empty in the initial time when the wort stays quite still. And don't bother with a buying fancy aeration stone thingy, just the tube as is works wonders enough.

Wassail!

Answer 6

I have only ever used table sugar for priming my beer and never had an issue(40+ batches).

If you are struggling with temperatures I find that the hot water cupboard normally has a good temperature to help them carbonate. Put a few in there and see if you can get the temperature raised a bit. Another place would be on top of the fridge because they give off a little heat too.