From Tree to Picnic Blanket

What would a summer picnic be without some fancy appetizers? Whether green or black, in oil or brine, stoned or filled, olives are one such delicacy that has vacuum in its story from harvest to packet – and in these processes, vacuum pumps from Busch are used.

Olives take a lot of time and effort before they arrive on the plate. Straight from the tree, they contain a bitter chemical compound called oleuropein and go through a lengthy curing process – essentially pickling them – before they reach the familiar salty, sweet-but-bitter taste olive fans love. And in two other stages in their journey to becoming delicious antipasti, olives may meet a vacuum system: when being plucked from the tree, and when they are placed into their final packaging.

The gentle pull of vacuum

Olives grown on a commercial scale are a challenge to pick. Some orchards can have as many as 900 trees per acre, each of which can produce up to 90 kg of olives. These vast numbers need more than just a few people picking individual fruits. And here, some olives have their first brush with vacuum technology. In particularly large olive orchards, one effective and speedy mechanical solution uses a vacuum system – rather like a giant vacuum cleaner – which suctions the olives from trees. As well as increasing efficiency, this is a particularly gentle method of harvesting that causes less damage or bruising to the fruits during picking than a mechanical or manual method might. The olives are then sorted and sent to the next step in the process, either to be cured, prepared, and eaten, or to be pressed into oil.

A protective atmosphere

For the olives destined to become appetizers, packaging is where vacuum makes a second appearance in their story. Keeping such fragile antipasti fresh and looking good can be a bit of a balancing act. The olives need to stay in shape, maintain their color and flavor, and be protected from damage along the way. Tray packaging with a modified atmosphere is a good solution that fulfills these criteria. First, vacuum pumps are used to remove ambient air from the packaging. Then, to take its place, CO₂ N₂, a protective gas mixture that will extend the olives’ shelf life, is pumped in. This lower oxygen content stops the oxidation process, ensuring that the olives look and taste as good as they did when they entered the packaging. The gases in this packaging method also provide good cushioning for the olives during transport. The tray is then closed with a plastic foil lid, which acts as a gas-tight seal to keep the protective atmosphere in. Vacuum pumps from Busch can provide the necessary vacuum for modified-atmosphere food packaging, making sure the customers always receive their delicacies in the best condition.