Topic: Calling New Zealanders! (Read 696 times)

The addition of salt to the gallon jug leaves less room for water, and the lower freezing point means that the temperature difference across the insulation is a greater span.  I.E. keeping food below 40 degrees is about a 35 degree span to maintain, but keeping the frozen foods frozen needs to be around 15 degrees to be certain that all of it stays frozen, so the span is a 55 degree difference.  That's my theory, anyway.  I didn't expect the salt ice performance to be so poor.


I have a pretty big cooler, so I can fit four gallon jugs (one at each corner) at about 32 pounds of ice and another 20 pounds or so of loose ice cubes; this will keep the food below 40 degrees for at least 4 days in 75-80 degree weather, out of the sun.  I have a large deep freezer, so I can keep much more than that.


Considered it.  Can't stand it.  Won't even bother to ask my wife to try it.

Salt will lower the freezing point, but I wouldn't expect salt to have an effect on temperature retention. Perhaps it has something to do with an earlier phase change from ice to water? Water is more dense than ice (at least the ice you are dealing with), saltwater can be colder than fresh water, and water completely surrounding your food will keep it colder longer than pockets of air and ice at the same temperature. But of course locking the food in solid pieces of ice with no air will keep it coldest.

I think the big gallon ice cubes are good as they should melt slowly, but their size and shape may make it difficult to pack tightly. You want to limit total surface area of your food and ice.

Have you considered clarified (ghee) butter? It last longer, might not need refrigeration, sautes well, tastes nutty, and you can make it yourself.

Not quite, just trying to stock my pantry for my own comfort for the next power outage.  In the Fall of 2008 there was a huge windstorm that ripped across my area, knocking out power to half the city and littering the entire city with debris.  I didn't have power for 4 days, and I live in an urban area.  Others didn't have power for two weeks, out beyond the suburbs.  I'm using that four day mark as my target.  We managed okay on peanut butter and crackers, but if canned butter can generally live up to expectations, it would be a great addition.  I just have to show my wife that it actually tastes and cooks like butter, and without the metallic taste that some canned foods have.  In order to do so, I need a can to test. 

During the outage, I came to realize that what we needed most was refrigeration, since we just read by candlelight rather than stare at the tv.  I bought a Colman brand Xtreme cooler, and have taken to filling the spare space in our deep freezer with old milk jugs filled with tapwater.  I've used a refrigerator thermometer to test the cooler to see if it can live up to the hype and keep the inside of the cooler below 40 degrees F. for four days with less than half the internal volume as ice.  It can, but barely.  I also tried doping the jugs of water with salt of different measured amounts, in order to see if I could do the same thing with frozen items, and thus use two coolers; one to keep things refrigerator cold, another to keep frozen things frozen.  The salt doped jugs couldn't seem to keep the inside of the cooler below freezing form more than a full day even at one cup salt per gallon jug, and salt doping reduced the cooling power of the jug to such a degree that at one quarter cup salt per gallon jug couldn't quite keep the same cooler under 40 degrees for two days, all other conditions being equal to the freshwater experiment.

Are you preparing for the Great Flood?

I'm looking for Red Feather brand canned butter, in small cans.  I can get it by the case via several sites online, but have not been able to find it locally.  I want to buy one small can, for a taste test.  I'm trying to compare some canned butters, for my long term pantry, that my wife won't reject; and I've found some high reviews for Red Feather.