FAQs

Frequently Asked Questions


Henkovac has dealers in almost 70 countries. Please check with our sales department for a local dealer for information about the henkovac machines and for service and parts. E-mail henkovacvietnam@gmail.com or call +84-945 252 686
Our machines last a very long time and we keep many parts in stock so there is a good chance we still can help you out.
The Henkovac vacuum machines are reliable and durable and don’t need much maintenance. Teflon tape and the seal wire of the seal beam are typical wear and tear parts which can easlily and quickly be replaced. The oil of the vacuumpump has to be replaced at certain intervals to guarantee good vacuum and a long life time of the pump. The control unit has a build in service intervention counter based on running hours or cycles. The indication signals ahead of time at the start up of the machine when the service intervention has to be planned and you may want to contact your dealer.
Soft air is an option on the sensor controlled machine that slowely brings the airpressure in the machine back to atmospheric level. This allows the plastic to wrap and stretch around sharp edges of the product wich might otherwise puncture the plastic bag. This option might later on be added on a 10 program sensor controlled machine.
Some products cannot be packaged under vacuum but may better packaged by replacing the air by an inert gas like Nitrogen (N2), Carbondioxide (Co2) or Oxygen (O2) to increase shel life bit als apperance. The suppliers of the gas are experts and can give advice wich gas or gas mxture is best suitable for the product to be packed.
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.
The vacuum bag is sealed closed by a heating wire.
  • A seal with one seal wire is called ” single seal”.
  • Most common is the double seal which provides 2 seals for extra security.
With a “trenn seal” one wire will seal the bag and the other heating wire will almost melt off the remainder off the bag. By pulling the remainder off the bag will have a nicer appearance. Also possible product that might be left in the remaining plastic is removed for better hygiene. Bi-active seal is especially used for very thick bags, mostly aluminium lined bags.
  • With a time controlled vacuum machine a time is set and the vacuum level can be monitored with an analoge vacuummeter. Excellent vacuum levels can be reached but indication of the vacuummeter is less accurate then a digital controlled unit.
     
  • With a sensor controlled machine the vacuum is measured with a sensor with very high accuracy and the results are digitally displayed. This results in shorter cycle times because when the desired vacuum level is reached the machine will immediately start the next operation. The total cycle time will be shorter than with a time controlled machine and some more options are available like H2O, MAP and soft air.
     
  • The 10 program time controlled machine can later on be equipped with a sensor. (not possible for the 1 program time controlled machine)

For vacuum packaging special vacuum bags are required. The bags are coextruded with mostly a combination of polyethelene (PE) for strength, but also for sealability, and nylon (PA) as a barrier to prevent air from penetrating the bag over time. Good quality bags will maintain vacuum in the bag over a long period. The bags are often treaded so that the don’t stick together and processed in a clean environment. Special cook bags will allow the product to be heated in a water bath inside the bag.

Please take a look at the shelflife extension table in this website. It lists many but not all products. Please take note of the hygienic conditions before packaging.