Using Vacuum Sealers At Higher Altitudes

have a look at this report re high-altitude canning ( nothing on sealing mentioned ) :

http://www.ext.colostate.edu/pubs/foodnut/p41.html#3k

you might want to contact thecompany here :

https://secure.foodsaver.com/ContactUs.aspx

Thanks, Hamburger. I was doing that at the same time I wrote the post. Pretty much sent them the same question via their customer service email desk.

If I hear anything, I'll post it here.

I was just wondering if there was any scientific reason that a vacuum would not occur at the higher elevation. I know that some things have to be packaged differently for higher elevations and that it takes water a few minutes less to reach the boiling point. I don't understand why the elevation would effect the ability to form a vacuum... Maybe the motor on the sealer just needs to be more powerful for higher elevations.

Thanks again. That's a good reference site. I've bookmarked it for future use.

From the Colorado site, I find these facts:

At altitudes above 3,000 feet, preparation of food may require changes in time, temperature or recipe. The reason, lower atmospheric pressure due to a thinner blanket of air above. At sea level, atmospheric pressure is 14.7 pounds per square inch (psi), at 5,000 feet it’s 12.3 psi, and at 10,000 feet only 10.2 psi - a decrease of about 1/2 pound per 1,000 feet. This decreased pressure affects food preparation in two ways:

1. Water and other liquids evaporate faster and boil at lower temperatures.
2. Leavening gases in breads and cakes expand more quickly.

The temperature at which water boils declines as elevation rises (Table 1). Because of this, foods prepared by boiling or simmering cook at a lower temperature at high altitude than at sea level, and thus, require a longer cooking time. Meats cooked by simmering or braising may require one-fourth more time at 5,000 feet than at sea level. Oven temperatures, however, are not affected by altitude, so sea-level instructions work for oven-roasted meats. Hard-cooked eggs will also take longer to cook. A “three-minute” egg may take five minutes to cook at 5,000 feet. High altitude areas are also prone to low humidity, which causes the moisture in foods to evaporate more quickly during cooking. Covering foods during cooking will help hold in moisture.

Fruits, tomatoes and pickled vegetables can be safely canned in a boiling water bath. However, because the temperature of boiling water is lower at higher elevations, you need to increase the processing time by one minute for each 1,000 feet above sea level if the sea level time is 20 minutes or less. If the processing time is more than 20 minutes, increase by two minutes per 1,000 feet.

Other vegetables, meats and poultry (low-acid foods) must be canned in a steam pressure canner at 240 degrees F for the appropriate time to destroy heat-resistant bacteria. At sea level to 2000 feet, 11 pounds of steam pressure will produce this temperature. Above 2,000 feet, steam pressure must be increased to reach 240 degrees F as illustrated in Table 2.

I suspect the vacuum sealer doesn't create an actual vacuum; it probably just reduces the air pressure inside the bag to about the same pressure as there is at 5000 feet....

i don't know the scientific/technical reasons for the difference in cooking time ... but this caught my attention in wiki :



( i doubt that you want to get into a philosophical debate about this subject but just want to seal the food properly ... smiles )

canning tomatoes surely brings back lots of memories as both my mother and my grandmother canned tomatoes every year. each batch (about 20 lbs=7 quarts) would take all day and they usually canned around 50 quarts every season. they did the same with green beans so it seems there was canning going on for months. This was all in colorado but I don't remember anything about changes for elevation, I suppose they knew by experience.

so I'm wondering, is this question answered? I'm curious myself.

I got a form letter back from the customer service that was basically a cut and paste from the manual. They said they'd be better able to help me if I'd call their customer service (rather than emailing) and have the food saver with me so they can troubleshoot it. No mention of anything related to altitude.

Haven't had the time to devote to it yet. Hopefully, tomorrow things will lighten up around here and I can do that.

Meanwhile, I've been doing some more research on the model of Foodsaver I bought and apparently there are hundreds of people with similar problems with it only sealing and not vacuuming. Apparently there is some packing material hidden way up in the inner workings that a lot of people have trouble spotting and removing. I checked as best I could without taking the thing totally apart and found nothing. The older models have the better reputation.

That doesn't explain why the old one doesn't work here though.

If I hear anything related to altitude from customer service, I'll post it here.

It seems to me we are at the borderline re serious altitude concerns, even if there is a progression re worries about vacuum and altitude (my memory is that we are at approx 5100, maybe you have better info) so I'm figuring maybe there is some other answer.

This reminds me of the miserable printer/scanner I bought a year or so ago - customer service was out to lunch in a big way, in that situation. Luckily I could return the thing.
Time has erased my memory of sureness of what the company was.

Didn't have time to hang on the phone with customer service while they had me repeat all the steps I already did before determining it wasn't working right.

Yesterday, I finally had some time to tear apart the machine and look at all the inner workings. Noticed one of the gaskets around the vacuum mechanism deep inside the machine had not been assembled properly at the factory; it was all twisted rather than smooth on one side. I neatened it up and put the thing back together again and behold! We now have a food saver that works!

Still no explanation for why the old one that worked for 10 years in the SF Bay Area does not work here in ABQ. Oh well...

So, I guess the answer is that the high altitude could or could not have an effect on the mechanism. It is possible that the older model can not handle the high altitude while the newer model, once properly assembled, is able to handle the higher altitude.

Note to Osso: In all the references I've seen, they have Albuquerque as being at 5,312 feet. Wikipedia goes into more detail:




High altitude cooking/baking adjustment charts start at 3,000 feet. For canning, for instance, we're supposed to add 1 minute of processing time for every 1,000 feet above sea level unless the processing time is more than 20 minutes. If more than 20 minutes, then it is 2 minutes of processing time for every 1,000 feet above sea level.