Vacuum cooling: Ensuring product quality and optimizing storage life

Many vegetables, flowers, herbs and fruit quickly age after harvest. At harvest temperature, respiration and transpiration could be up to 25 times higher than with at optimum storage temperature. Sam Heemskerk of Weber: "It's logical that it's important to take away most of the field heat as quickly as possible after harvesting. With many products, vacuum cooling is a perfect method for this, ensuring optimal product quality, and optimizing storage or vase life."

Vacuum cooling is a pre-cooling technique with an average cooling time of only 15-30 minutes. Vacuum cooling reduces:

The degree of respiration (and thus the risk of botrytis [in flowers] and black rot [in vegetables])
Transpiration, and thus loss of fluids (maximizing your yield)
The production of ethylene and the sensitivity to this
The development of microbes (and thus the percentage of production loss)

Withdrawing heat
Vacuum cooling withdraws heat from products through forced evaporation of a small percentage (usually 2-3%) of the product's own fluids. That generally occurs under low pressure. The energy that's released in forced evaporation, lowers the product temperature. Vacuum cooling is suitable for (non-airtight) packaged products.

Constant end temperature
Sam Heemskerk: "It's the only method that guarantees an almost perfectly constant end temperature, making it the ideal solution for quickly recooling varied shipments on airports and logistical centers, without any risk of freezing. Vacuum cooling also shortens the time-to-market ("same-day delivery"). It gives a more constant and low cold store temperature, and longer storage options. Finally, vacuum cooling is energy efficient."

Sam Heemskerk, Weber Cooling, at the vacuum cooling test setup

For more information:
Weber Koudetechniek
Sam Heemskerk
M: +31 (0)6-19 834 845
E: sh@weberkoudetechniek.nl
www.weberkoudetechniek.nl