Every consumer co-op in Japan uses blue ice, the cold storage agent, hereafter, "agent" that keeps the proper temperature when delivering refrigerated goods, fresh vegetables and fruit to the members' homes.
The Palsystem Consumers' Cooperative Union also uses the same agent but has now developed a new one exclusively for fresh produce in collaboration with its business connections and started using it since last July. The aim of this new agent is not only for delivery at the appropriate temperature but also for goods' quality maintenance and lowering the operation cost.
new cold storage agent
Palsystem keeps dairy products, delicatessen and meats, etc. refrigerated throughout the year and vegetables and fruits between April and November, in an insulating container which has appropriate temperature inside using the 0℃ (the point of fusion is -1℃ to 1℃) cold storage agent. Fresh produce are damaged being frozen or changing color at low temperature when they directly touch the agent. So far the delivery staff prevented the goods' quality from deteriorating by putting a buffer material between the agent and the fresh produce.
However, the appropriate temperature for vegetables and fruit was found to be 12℃ and the new agent to preserve the fresh produce with appropriate temperature range was developed through the Palsystem's research with the business partners. The cold storage agent starts to melt at 12℃ and changes from solid to liquid. At that time it absorbs the heat inside the container and functions to keep the temperature of the air and the fresh produce inside the container appropriate.
For Zero degree cold storage agent（Left）→Change in color or bruise (Chilling disorder)
For cold storage agent with appropriate temperature of 12°C（Right）→No change
Furthermore, Palsystem tries to drastically reduce electricity consumption with the introduction of the new cold storage agent. The former agent took 18 hours to get frozen using a powerful freezing apparatus. On the other hand, the new one takes 12 hours and it is estimated that the power consumption to freeze will be reduced by 40% of the former one, which is equivalent to around 2,000 tons of CO2 that will be reduced (*1).
(*1) Calculated from the Ministry of the Environments "Fact-finding Survey on the Estimation of Carbon Dioxide Emissions from Households, National Test Survey (October 2014-September 2015)", and "Emission Factor by Electric Utility Operator for greenhouse gas emission of Specified Emitters (Calculated from FY2018 results for CO2 emission conversion)