In my column #2, I mentioned the difference of food-hygiene circumstances between nations. I concluded that it is important for Japanese, who already have high-level hygiene, to cherish and preserve the proud tradition without easily adopting foreign standards as they are.
Food hygiene control in Japan should aim at an even higher level, and its concept and operation need to be very delicate. My column #1 is a case example that shows the importance of this attitude.
To keep the level of Japanese food hygiene and quality control high, cold chain plays an important role.
Cold chain in Japan is very extensive. It has a wide variety of forms from domestic trucking of vegetables to overseas ship transportation.
When and where did the cold chain come about? It seems to be around 1920 in the United States. In a movie “East of Eden” which is set in that period, the main character’s father started a business of delivering vegetables with ice by train. However, the term “cold chain” was first used by Europeans who visited the United States to inspect the method to deliver foods over a long distance. Their report was the first appearance of this word.
If the food delivery with ice in the United States should be called “cold chain”, Japanese people had started something like cold chain well before then. It has been recorded that Kaga Domain (current Ishikawa Prefecture) used to present ice to the Shogun together with sea breams caught in the Japan Sea. People in snowy region including Kaga had already been preserving foods with ice. This delivery from Kaga to Edo might be called cold chain in the Edo Period.
In the late 1950s, cold chain became more and more popular with the widespread of electric refrigerators primarily in developed countries. As for Japan, Resources Council of Science and Technology Agency issued a recommendation so-called “Cold Chain Recommendation”. This was aimed at raising an alarm over negative health effects of poorly-balanced meals caused by diversification and advancement of diet in the course of rapid economic growth. Also, this recommendation was intended to inform the people of the need to put low-temperature distribution in place in order to ensure healthy and rich diet.
After the issuance of this recommendation, then Ministry of Agriculture and Forestry played the main role in building production and distribution facilities for vegetables, fruits, livestock products and seafood all over Japan. The Cold Chain Recommendation added momentum to the development of technology such as precooling and distribution/storage at low temperature. This shifted Japanese diet from “quantitative fulfillment” to “qualitative satisfaction”.
Japanese people realized easy access to a wide variety of quality foods and this led us to the age of plenty.
Preservation of freshness and quality of food slightly reduced the number of food poisoning cases temporarily, but the number of sufferers has been staying almost the same. This might be regarded as a result that the scale of food poisoning incidents has become ever larger.
The effect of the recommendation cannot be completely denied because circumstances surrounding food distribution of the time were changing very rapidly and many other factors do trigger food poisoning. In those days, minimum infective dose of many food-poisoning microorganisms was believed hundred thousand or million. That is to say, people of that time believed refrigeration of food could prevent food poisoning.
The food poisoning incident in 1999 caused by enterohemorrhagic Escherichia coli O157 revealed the existence of microorganisms that infect humans with a small amount. Recently in Japan, more than 80% of food poisoning incidents are caused by small-amount infecting microorganisms. Also, most of the incidents are due to cross-contamination.