MAP machines
 Vacuum
chambers (VC)
These machines use preformed bags and utilise the compensated
vacuum technique to replace air. Preformed high-barrier
bags are manually placed within the chamber before evacuation,
back-flushing with the desired gas mixture, and heat
sealing. These machines can be used for small scale production
of vacuum or gas flushed catering packs.
The product to be packaged is put into a film pouch
and placed in the vacuum chamber. When the lid has been
closed, the programmed level of vacuum is produced in
both the vacuum chamber and the pouch. The pouch is then
either sealed in a vacuum (vacuum package) or the chamber
(and thus the pouch as well) is filled with a Freshline® MAP gas before the sealing operation (modified atmosphere
package)
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 Snorkel
Type (ST)
These machines use the compensated vacuum technique
to produce bulk MA catering bag-in-box packs. Alternatively,
they can gas flush conventionally packaged retail products,
such as overwrapped packs of red meat, into large master
packs. In these machines, preformed plastic bags are
positioned on a heat seal mandrel and retractable snorkels
pull a vacuum and then back-flush with a desired gas
mixture before heat sealing. |
Tray lidding
A traysealer uses ready-made trays that are sealed in
much the same way as a thermoformer. The top web of packaging
material (lid film) covers the filled pockets/trays.
The air is evacuated from the sealing die and protective
gas is added. Then the pack is sealed by the application
of heat and pressure. Tray lidding machines are available
from tabletop (manual) for the small producer, to fully
automatic inline versions for larger processors.
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Horizontal form-fill-seal
(HFFS)
These so-called flow-pack machines (see diagram above)
are capable of making flexible pillow-pack pouches
from only one reel of film. Horizontal form-fill-seal
machines can also overwrap a pre-filled tray of product.
The air from the package is removed by a pulse of gas
or continuous gas flushing, but gas mixtures containing
levels of O2 > 21%
cannot be used due to the use of hot sealing jaws at
the end of the machine. For certain very porous products
(e.g. some bakery goods), gas flushing is not capable
of reducing the residual O2 within the package to low
levels. In some cases, a gas injection station can
be fitted to the machine infeed so that the product
itself is purged with gas immediately prior to packaging.
Vertical form-fill-seal (VFFS)
A vertical machine forms a tube, it then fills with product
(in most cases dropped from an overhead multi-weigher),
purges with gas and then seals. At the same time film
is transported vertically downwards. VFFS machines are
predominantly used for packaging foods in powder, granular,
shredded and dried form. |
Thermoform-fill-seal
(TFFS)
Packaging material for the base web (thermoformable film)
is unwound from the reel. It is heated in the forming
die and formed into pockets/trays. The formed pockets
are loaded manually or automatically. The top web of
packaging material (lid film) covers the filled pockets/trays.
The air is evacuated from the sealing die and protective
gas is added. Then the pack is sealed by the application
of heat and pressure. The web of packs is cut across
the machine direction initially. Production of the individual
packs has been completed after the longitudinal cutting
operation.
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| Contact us : |
 |
Freshline® Hotline
+44 (0) 1270 614111 |
| or click here |
|
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| Chambers are
available in a wide range of capacities; from tabletop
to freestanding swing-lid versions. |
|
| HFFS/flowrap
rotary jaws are generally not compatible with MAP. |
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