https://www.engineersedge.com/h2o_boil_pressure.htm
Here is a link to a table of the boiling point of water at different amount of vacuum.
I generally SV between 131-140* for longer times, but for those who cook above 145* with a full vacuum this might be interesting.
I looked up a couple videos of people testing the vacuum on their vac sealers. These were the common Food Saver types. In the tests I saw, they were able to pull between 18 and 22 inches of vacuum. A Vacmaster might be able to pull slightly more, I don’t know. Anyway, according to the chart in the link water will start to boil around 145* with 22 inches of vacuum. The higher the temp the more likely this is happening.
I read a food science study where they tested chicken and fish at different rates of vacuum. They were using a chamber style machine common in commercial kitchens. They vacuumed chicken and fish at 90%, 95% and 99% plus 15 seconds Vacuum. I’m guessing on the high side they had 28-29 inches of vacuum much more than you could produce at home. They cook these different pieces at the same temp and time in SV bath. The results were with the 99% vacuum the meat was watery, but dry to the mouth and mushy. The 90% vacuum was described as perfectly cooked And was preferred by all in the test. Beef was also tested the same way, and while no significant texture difference was noted, they all preferred the 90% vacuum.
Im wondering if varying the amount of vacuum from cook to cook can change the finish product given time and temp stay the same? Since it’s hard to know how much vacuum is applied from seal to next I just don’t know. What say you?
For the most part I use ziploc type bags and use the submersion method to expel the air.
Here is a link to a table of the boiling point of water at different amount of vacuum.
I generally SV between 131-140* for longer times, but for those who cook above 145* with a full vacuum this might be interesting.
I looked up a couple videos of people testing the vacuum on their vac sealers. These were the common Food Saver types. In the tests I saw, they were able to pull between 18 and 22 inches of vacuum. A Vacmaster might be able to pull slightly more, I don’t know. Anyway, according to the chart in the link water will start to boil around 145* with 22 inches of vacuum. The higher the temp the more likely this is happening.
I read a food science study where they tested chicken and fish at different rates of vacuum. They were using a chamber style machine common in commercial kitchens. They vacuumed chicken and fish at 90%, 95% and 99% plus 15 seconds Vacuum. I’m guessing on the high side they had 28-29 inches of vacuum much more than you could produce at home. They cook these different pieces at the same temp and time in SV bath. The results were with the 99% vacuum the meat was watery, but dry to the mouth and mushy. The 90% vacuum was described as perfectly cooked And was preferred by all in the test. Beef was also tested the same way, and while no significant texture difference was noted, they all preferred the 90% vacuum.
Im wondering if varying the amount of vacuum from cook to cook can change the finish product given time and temp stay the same? Since it’s hard to know how much vacuum is applied from seal to next I just don’t know. What say you?
For the most part I use ziploc type bags and use the submersion method to expel the air.