Go to the Article: Getting Bubbles in Your Beverage
Now this is good info. Wish the other episodes had as much scientific explanation. I wondered why one had to charge and then vent. Obvious now, in order to get air out because CO2 is heavier than air
excellent, very informative. Thank you
Good info! We've been carbonating water in 5 gallon soda kegs (instead of importing San Pelligrino) and the first few liters aren't sparkling; it gets carbonated after that, and wondered why. Now I see we need to vent the air in order to get actual CO2 pressure to carbonate.
I tried making a plain club soda with just water. I vented the first cartridge, and then used two more (in a .25L siphon), but the water was still very flat after opening. Any thoughts on what I may have done wrong? How long does it typically take to carbonate liquid?
When they say ice cold water they mean it. I tried it just now. Room temp water in the shell, flat barely bubbling stuff. Ice water and a good shake-- instant fizzy soda water.
This seems like a good place to ask my question. I've been researching how to use a CO2 tank and regulator to pressurize my whipping siphon instead of the individual chargers. This guy does it with a soda siphon http://www.amazon.com/gp/customer-reviews/R35XKX16LHTYB4/ref=cm_cr_pr_rvw_ttl?ie=UTF8&ASIN=B00007JXR7 like this:
I'm trying to figure out what pressure to set the regulator for carbonating in the whipping siphon. I've seen conflicting advice online, some in the 30-50 psi range, and some around 130 psi or more. Commensurately, there are two types of regulators I've seen, a lower pressure one intended for draft beer, and a higher pressure one for soda. Do you have any advice?
I inquired from iSi directly about the regular operating pressure; below is the response I received. The short version is that an empty 1 liter whipping siphon is 46.4 psi (1 charger) or 92.8 psi (2 chargers). With 1 liter of chilled water inside, it's 188.5 psi (1 charger) or 246.5 psi (2 chargers). Those pressures will drop slightly as the water absorbs the N2O or CO2 (though CO2, being more soluble in water, will drop more).
Here's the full response from iSi:
If you charge an empty 1 liter cream whipper bottle with 1 x iSi cream charger the pressure inside the whipper will be approximately 46.4 psi (3.2 bar). If instead you charge the whipper bottle with 2 x iSi cream chargers you will simply get double the pressure (92.8 psi or 6.4 bar). If instead of using cream chargers you decided to use soda chargers the pressure will be almost the same.
Determining the pressure inside a 1 liter cream whipper when it is filled with either heavy cream or water turns out to be a very difficult thing to calculate without specialized measure equipment. Luckily iSi has the equipment needed to measure this so I was able to get you some answers:
A 1 liter cream whipper bottle filled with 1 liter of chilled water (t= 7.5°C) and charged with either 1 or 2 cream or soda chargers:
1 x iSi cream or soda charger (whipper not shaken) = the pressure inside the whipper is approximately 188.5 psi (13 bar).
2 x iSi cream or soda chargers (whipper not shaken) = the pressure inside the whipper is approximately 246.5 psi (17 bar).
NOTE- If you shake the cream whipper bottle (say 5 times) the pressure will reduce due to the solubility of CO2 or N2O gas in water. In this scenario, the shaken bottle pressure will be less when using soda chargers than when using cream chargers due to the higher solubility of CO2 in water (compared to than of N2O). If the 1 liter cream whipper bottle is instead filled with heavy cream the pressures will be similar as above with the exception that the pressure of the N2O (cream charger) filled bottle will be slightly lower. Again this has to do with the high solubility of N2O in fat (cream). Simply put N2O dissolves better in fat than CO2.
The biggest influences on the internal pressure of a cream whipper are as follows:
1. The quantity of filled cream/water in the canister. The less cream/water in the bottle, the less the internal pressure will end up being.
2. The temperature also influences the internal pressure. In general, the lower the temperature of the liquid the lower the pressure will be.
3. The type of liquid…this has to do with the solubility of the gas in the liquid. The higher the solubility of the gas in the liquid the lower the internal pressure. Note- the solubility of N2O in cream depends on the fat content…the higher the solubility, the lower the internal pressure of the bottle.
There is another aspect many are missing. dissolve gasses in the water before it is introduced to the charger. Easily corrected. When Ice Sculptors freeze their medium, they first boil it (or otherwise force out dissolved gasses.) When you freeze water, you see all the bubbles? that is the dissolved gas in the water. boil it, then pop into the freezer and you don't have that problem. you can also achieve the same end with a microwave. obviously, you don't want to put boiling water straight in to the fridge. I zap mine, then pour it still steaming, into a flexible container, let it come to room temp (or drop into an ice bath) then into the freezer, if you want ice.
For the purposes of carbonated beverages, hang onto old 2 liter bottles, boil the water and store it in the 2 liter bottles. It can also be chilled in those bottles and poured straight from them into the Charging container. I found a really neat little one on amazon, hand held, for $15. If you are willing to take the extra steps, you can save a lot of money and not a little trash, making your own sodas. and the flavors you can create are really terrific!
