Products with a high water content like soups and sauces need special care since at a lower air pressure (vacuum) the liquid will start to evaporate quickly, a process which looks like boiling but at a lower temperature than 1000C.
This will not cook the product (because of the low temperature) but dry it out, loose moisture and may spatter out of the bag, soiling the machine and package. A special H2O program on the control unit will exactly measure this “boiling” point, which is also the point at which vacuum is reached and all the air is out of the package, and seal the bag. Additionally the moisture will not be collected in the oil of the vacuumpump which would increase the oil changes.