Opportunities exist for industry to develop technologies with much greater flexibility
Frozen food manufacturers and cold store operators could cut CO2 consumption by 4,800 tonnes annually, according to a new report from the British Frozen Food Federation.
Researchers from Enviros Consulting analysed cold storage at eight food manufacturers and five logistic service providers for the report ‘Improving the energy efficiency of the cold chain’.
Enviros put forward eight areas for energy saving. Among the recommendations were reducing temperature differences between air and refrigerant. Coldstore temperatures were around -21 deg C, but the evaporating temperature of two of the plants was excessively low at -36 deg C and -40 deg C.
Secondly, researchers suggested splitting blast freezers and cold stores and avoiding over-cooling in blast freezers, or “lowest common denominator cooling”.
The researchers said raising cold store air temperature and suction pressure control by about 6 deg C would give energy savings of more than 15 per cent. Similarly, if the evaporating temperature can be raised by 4 deg C from -32 to -28 deg C, savings of about 11 per cent can be achieved.
The report also noted that some frozen food manufacturers and cold store operators will set their cold stores well below -18 deg C as there is concern that products will be exposed to warmer temperatures later in the supply chain – over chilling acts as insurance, the report concludes.
The quick frozen food directive has a required storage temperature of -18 deg C to preserve quality and hygiene.
Brian Young, director-general of the BFFF says the survey’s findings are a good opportunity for the industry to develop technologies that both food producers and logistic service providers can use with much greater flexibility.
He said: “Our survey has found that too often plant rooms are inflexible and do not happily allow producer blast freezing and store freezing to happily co-exist.”
“The report has identified significant carbon saving opportunities and therefore I would expect both food manufacturers and refrigeration technology suppliers to treat this as a priority. The project findings show there is scope to improve cold chain efficiency with relatively little capital investment. We hope our findings will initiate dialogue so the industry as a whole can work together to improve its sustainability.”
Eight ways to improve the cold chain
- Raising of cold store air temperature
- Reduction of temperature difference air - refrigerant
- Seasonal adjustment of evaporating temperature
- Avoiding air temperature fluctuations
- Splitting blast freezers and cold stores
- Avoiding over-cooling in blast freezers
- Using variable speed drive fans
- Ensuring a flexible and effective defrost system