bottle filling vs. thermal expansion

[nick-o-rye]

I was filling a new bottle we are about to offer (375 mL) with vodka and it went half way up the neck. When i went and showed my boss i said that the vodka was cool around 70 degrees (cool for texas) and if it sat in a trunk at over 100 degrees the cap could blow off, or at least leak. So that got me thinking about the 4 other sizes we offer (50 mL, 750 mL, 1 L, and 1.75L). If we bottle at ambient (around 85-95) and the ttb did a check and they have it in a cool room the levels are going to be off. I was wondering if there were any industry standards or guidelines to filling temps and thermal expansion. Or if anyone knows where the ttb has addressed this (chap. 6 was not helpful).I wanted to get the forums opinion before i raised any flags at the ttb. thanks for any input

-nick

[will]

nick,

your fill checks should be done by weight. if you're not doing it that way, your results will likely be wrong.

a 750ml bottle of 80 proof spirit (not a cordial containing sugar) will weigh 712 grams.

the process is simply to weigh a representative sample of bottles, and mark the weight on the glass. send them through the filling line and take them off at the other end. weigh them again, and subtract the bottle weight. this is your fill weight. convert that to mL by the formula volume = Wt * 750/712. adjust your bottle fill machinery so that over the long-term you have the same number of overfills as underfills. do this before, during, and after each bottling run. keep records of this work. this will satisfy the TTB.

you should be aware that bottles manufactured for spirits are designed to provide much more headspace than bottles made for other purposes, particularly wine. wine bottles are designed to minimize headspace because more headspace means air, and that means a greater chance of oxidation of the wine. wine at around 15% abv has very different expansion characteristics than spirits at 40% abv.

good luck,

will

[nick-o-rye]

awesome, thank you for the info it will be put to good use.

-nick

[PeteB]

This won't help you with your expansion problem, but I find it an easy way to check fill volumes.

My bottle filler draws straight from the container that is sitting on a platform scale. Every dozen bottles I record the weight in the container. At the end I divide weight used by number of bottles and that gives me weight per bottle. Then it is a simple conversion of weight (mass) to volume at "standard" temperature. No need to weigh the empty bottles before you start. Temperature of spirit at bottling doesn't matter for the calculation, but the thermal expansion will affect the fill level adjustment.

Just bragging here, the last fill test I did with 8 dozen 500 mL bottles I had an average overerfill of 0.03 mL. Probably not enough to wet the cork.

[DISTILLATEUR]

what brand and model of scale are you using?

[PeteB]

what brand and model of scale are you using?

It is a NUWEIGH JAC929

Reads 0-150 Kg in 50g steps then 150-300 in 100 g steps, can also readout in pounds

[FrEwing]

nick,

your fill checks should be done by weight. if you're not doing it that way, your results will likely be wrong.

a 750ml bottle of 80 proof spirit (not a cordial containing sugar) will weigh 712 grams.

the process is simply to weigh a representative sample of bottles, and mark the weight on the glass. send them through the filling line and take them off at the other end. weigh them again, and subtract the bottle weight. this is your fill weight. convert that to mL by the formula volume = Wt * 750/712. adjust your bottle fill machinery so that over the long-term you have the same number of overfills as underfills. do this before, during, and after each bottling run. keep records of this work. this will satisfy the TTB.

you should be aware that bottles manufactured for spirits are designed to provide much more headspace than bottles made for other purposes, particularly wine. wine bottles are designed to minimize headspace because more headspace means air, and that means a greater chance of oxidation of the wine. wine at around 15% abv has very different expansion characteristics than spirits at 40% abv.

good luck,

will

Will, you specifically differentiated between whiskey and cordials with sugar. Do you have a recommenbdation for cordials.

Thanks

Dick Garofalo

[PeteB]

Hi Dick,

Will may come back with a different method from mine.

Work out the density of your cordial by using an SG hydrometer (EDIT - I should have said DENSITY hydrometer)

I have no idea of the reading but if we say it is 1.0020 g/ml,(Kg/L) then 750 X 1.0020 = 751.5 g per 750 mL bottle

or if it is say 0.97453, then 750 mL at 60F weighs 750 X 0.97453 = 730.9 grams

Density will need to be corrected to 60 F in USA

If you only have a proof hydrometer and it does not float up past the zero, you can still convert the actual reading to density with tables.

(the proof hydrometer is reading alcohol plus sugar etc but that does not matter for this calculation)

[will]

using only the equipment mentioned in my earlier post, you can determine the check weight of a cordial using the following method:

start with a bottle and a supply of distilled water and the cordial under test at the same temperature.

weigh the bottle.

fill the bottle with a known volume of distilled water by weight using 0.9990134 as the density of pure water at 60F (use .998203 at 20c outside the USA).

for instance, 750ml weighs 749.25 grams.

mark the bottle at the fill point.

empty and dry the bottle.

fill the bottle with the cordial to the same fill point.

weigh the bottle. this is the weight you are "shooting for" in the fill check above.

adjust your equipment to have the same number of overfills as underfills using this net weight.

good luck,

will