Priming per bottle Calculations...

[bigdaddybrew]

So I did some searching and find lots or varying opinions for per bottle priming. For starters...yes priming the entire batch is better. This is not that thread. I keg my beers but I like to bottle carb a few bombers so a per bottle calculator would be nice. So I figured out you can use the various calculators like this one...
http://www.northernbrewer.com/priming-sugar-calculator/

Enter specific information for your batch and divide that by number of bottles...
Desired Carbonation 2.5, temperature of beer 68F, Batch volume 5 gallons...
4.42 ounces of corn sugar

Convert ounces to grams
1oz=28.4grams
4.42 x 28.4=125.5 total grams of corn sugar

1 gallon = 128 ounces
5 gallons x 128oz= 640oz total batch size

Divide batch size by bottle size..
640/12oz = 53 bottles
16oz = 40 bottles
22oz = 29 bottles

Divide total grams of corn sugar by the number of bottles...
125.5/53= 2.4 grams per 12oz bottle.
3.1g per 16oz
4.3g per 22oz

How many grams of Corn Sugar per teaspoon? OMG! This was not easy info to find. But I found the label on dextrose (corn sugar) used by Bodybuilders...
1 teaspoon = 3.3 g
3/4 teaspoon = 2.5g
1/2 teaspoon = 1.7g
1/4 teaspoon = 0.9g

Bottle prime with Corn Sugar...
12oz 3/4 teaspoon
16oz 1 teaspoon
22oz 1tsp + 1/4tsp

Same calculations for Table Sugar...
1 teaspoon of Table Sugar = 4.2 grams
3/4 teaspoon = 3.2g
1/2 teaspoon = 2g
1/4 teaspoon = 1g

4.03oz = 114g of total table sugar...
2.2g per 12oz
2.9g per 16oz
3.9g per 22oz

Bottle prime with Table Sugar...
12oz bottle 1/2 teaspoon
16oz bottle 3/4 teaspoon
22oz bottle 1 teaspoon

I have not yet tried bottle priming using these amounts.
Any errors?
Do you see any issues?
Any thoughts?

 

[Qhrumphf]

I would never trust measuring sugar by volume. The volume of sugar can change substantially depending on how coarse the grain of the sugar is. Most folks quote 3/4 cup as being 5 oz of corn sugar. With the corn sugar I get from myLHBS, 5 oz of corn sugar is actually closer to 1/2 cup (maybe it was 2/3, I don't recall since I haven't gone by volume in a long time, but it was less than 3/4 cup). Point is, get yourself a proper high-resolution scale, and go by grams. For my polypins (1 gallon each) I prime individually and am usually looking at about 9 grams of corn sugar (for 1.4 volumes, nice and bright for cask ale).

Your math seems good. Simply dividing by the appropriate conversion. But use weight, not volume. At the levels you're going for, small changes can have drastic consequences.

 

[ChefRex]

Over the winter I have been drinking a lot of stragglers that I have bottled after kegging, I thought I was doing good at 2 grams per 12 ozs but now I am finding them to be overcarbed with a little more time on them so next time I will be reducing to say 1.7 grams.
I use an accurate scale, measuring using spoons may be asking for trouble, bottle bombs and all. YMMV

 

[bigdaddybrew]

I am not buying a tiny scale just to bottle a couple of bombers. If you have a tiny scale accurate enough to measure small amounts like these then that is probably better than measuring spoons but you still have to decide how much and in my search I found very little agreement. Some say this much, others say that much, some by weight, some by volume, one cube, 1/2 teaspoon, 2.1 grams, 1 Coppers drop, I do this, I heard that etc.

I did this to make a solid a starting point based on a trusted Calculator. Since I started using the calculator instead of just dumping in 4oz, my batch bottled beers have been consistently carbed. Now that I keg I wanted a quick way to bottle carb a few bombers or whatever. I will use the same measuring spoons, carefully level them and try to get every crystal in the bottle using a funnel. I will make adjustments based on outcomes. From all the reading I did over the last few years these measurements don't seem too far off from the general rules you see repeated in various Brewing Forums.

This is just a starting point and as I said I haven't tried these measurements yet. I'll let you know when I get results.

 

[ChefRex]

A blade scale is cheap and of good quality,
http://www.amazon.com/dp/B0012N1NAA/?tag=skimlinks_replacement-20

What do you use to measure hops?

 

[Qhrumphf]

As long as you're being consistent then it should be fine. But you need to use the exact same sugar (not just kind but brand). And if carb is too high or too low then adjust.

 

[bigdaddybrew]

I buy my hops by the ounce, put it on a plate a separate into to equal piles...1/2 ounce. Divide again...1/4 ounce. Brewing is more are art than science for me.

$9 aint bad if it's precise enough for tiny amounts of sugar. If you buy bulk hops it would be essential. I don't use enough of any one type of hops throughout the year to buy bulk.

Some brew kits come with a tiny two sided scoop for bottle priming and I have read positive reports. Others use sugar cubes with good results. I have tried this and it works, one cube per 12oz bottle but like Carb drops it doesn't allow you to scale up very well. Domino sugar cubes are listed as 2.5 grams each on the package. They report 198 cubes per pound. 1 pound = 454.4 grams so more accurately 454.4/198 = 2.3 grams and this is close to my calculations. I was careful to use the best cubes and not use the irregular ones.

Corn sugar seems to easily absorb moisture. I think moisture absorption is why brewers report so much variability in the weight vs volume. Think about it, if sugar absorbs water it will gain weight but should not gain volume as the water will fit in the space between the molecules? So weighing may not be as accurate as you think especially if the sugar has been stored improperly or is just old. Every time you open the container it absorbs moisture. When using a tiny amount of sugar what matters more? The variation in density by brand or the amount of moisture it has absorbed? Volume vs weight? Maybe this is why Ohrumpfh is finding that a 1/2 cup of corn sugar weighs 5oz?

Perhaps some experiments are in order. Weighing a given volume of fresh dry sugar different brands and types. How much does the density of the sugar really vary? Then let them sit out in an open container in the moisture of the bathroom for month and then weigh them again. How much did it vary? Did it gain volume? Did it gain weight? Not sure I care this much. Using fresh dry sugar should eliminate this variability and I don't think there can be that much difference brand to brand but I've never checked.

I think consistency is the key. I will use table sugar as it is always fresh at my house. I'll use the same measuring spoons and make adjustments based on results. I aint scared to try.

 

[bigdaddybrew]

Weight vs Volume?

After some more specific reading on the topic, I have come to some conclusions...

In chemistry you weigh powders, and measure liquids by volume.

Corn sugar is fairly "fluffy" and especially susceptible to "packing" and easily absorbs moisture.

Table sugar is more of a crystal and less susceptible to packing however it also absorbs moisture.

Weight is best but having a precise scale and fresh dry sugar is vital to accuracy.

Measuring spoons are going to be less accurate so using the same spoons and leveling technique as well as fresh dry sugar is vital.

Measuring small amounts for per bottle priming is difficult either way...

Corn sugar seems more susceptible to moisture absorption and "packability" so if your going to do some per bottle priming fresh dry table sugar is probably the better product whether you are measuring weight or volume.

My two cents. Now to put it to the test.

 

[mscroggi]

Thats a good read.. I am getting ready to do the exact same thing.. Keg my beer but bottle some bombers as well.. When I was at my homebrew store buying the ingredients, I asked the very question 'how much priming sugar for a bomber' ... the guy helping me grabbed a book, flipped a few pages and replied '1 1/4 tsp', which is exactly the value you came up with .. I agree with one of the posts that it's more important to be consistent in your method and ingredients and adjust if it doesn't come exactly like you would like.. This is where I am headed.. I am going to try the 1 1/4tsp and see how it does..

 

[z-bob]

I bought one of these scales last year, mostly to weigh hops. It works fine for weighing priming sugar too. https://www.amazon.com/gp/product/B000O37TDO/?tag=skimlinks_replacement-20

7 grams of sucrose (table sugar) per liter seems about right for most beer styles.

 

[El Nino]

I just throw in 1/2 a tsp of cane sugar in each bottle (with a funnel) and that works perfect for me. No need to worry if I mixed the priming sugar evenly, it's consistent carbonation in every bottle.