Cooling methods for fruit and vegetables : Around 6.26 million tonne of fruit and vegetables are grown in Australia in each year, roughly 20% of that is for export equating to $2.6 billion dollars to the economy. A CSIRO study found that Australia loses at least an estimate 18-22% of its fruit and vegetable biomass during the production and processing/packing stages also known as ‘post-harvest’. Cooling fruits and vegetables during these crucial stages is paramount to reducing this waste.
The storage life of fresh fruit and vegetables differs with each type, variety and pre-harvest conditions. Regulation of storage life can be managed by monitoring and controlling key factors during post-harvest management. Suitable control of temperature and relative humidity is vital to maximising storage life and quality of each produce.
Temperature is the single main influence in postharvest quality of vegetables. The temperature of produce drives water loss, changes in metabolic activity, loss of flavour, texture and nutrients and the development of rots.
Temperature effects are often divided into three main classes:
- Low temperature effects
- Mid-range temperature effects
- High temperature damage
Each has its own affect on quality such as freezing damage, chilling injury, rots and mould, flavour changes, colour changes, softening, wilting and dehydration. Quality is very much in the eye of the beholder. Different members within a given supply chain will all have different ideas of what constitutes good quality.
Respiration and transpiration are the most important postharvest processes affecting storage life and quality of vegetables.
Postharvest life can be prolonged and quality can be maintained by reducing the rate of respiration and transpiration.
Pre-cooling and storage at low temperatures slow down the physiological and biochemical processes associated with deterioration and decay. Low temperatures also reduce water loss through transpiration and delay the growth of micro-organisms which cause rot. An increase in the temperature of 10°C can increase the rate of deterioration and decay by two to three times.
Here are the Top 5 cooling methods for fruit and vegetables to optimise storage life for fresh produce, along with their relative advantages and disadvantages:
OTHER PRE-COOLING TIPS:
- Do not load pre-cooling facility beyond its optimum capacity.
- When stacking produce, allow adequate air-circulation to ensure all vegetables can be evenly cooled.
- Use proper receptacles (such as vented boxes and baskets for forced-air cooling, and waxed cartons or Styrofoam boxes for hydro-cooling).
- Transfer vegetables out from the pre-cooling facility immediately after pre-cooling, to avoid overcooling or dehydration of the vegetables.
- Use potable water for precoolers to minimise any food safety concerns.
- Separate ethylene-sensitive vegetables from ethylene producing ones.
- If a chiller is used for precooling, keep it closed at all times to minimise temperature and relative humidity fluctuations.
For all pre-cooling and post-harvest needs speak to the team at Heuch Fresh.
1300 001 952