Totally Wasted, Dude
Every once in a while, I see a news story that relates to the subject of food preservation that underlies the products we’ve made on this blog. The latest one: “Up to Half of All Food Wasted“. This story is based on a report by the Institution of Mechanical Engineers (IMECHE). One visit to their web site showed me that I should’ve been taking this subject more seriously a long time ago. Which is to say, I had no idea that entire trays of glazed danishes were hanging in the balance.
My first question was why IMECHE was interested in this subject. The answer came when I read the report: “Controlling and reducing the level of wastage is frequently beyond the capability of the individual farmer, distributor or consumer, since it depends on market philosophies, security of energy supply, quality of roads and the presence of transport hubs.” Yes, it’s true that engineer job security increases every time the words “inadequate infrastructure” are uttered. But they may have a point. As inputs become more dear and energy costs go up, the real cost of wasted food is bound to increase.
How can water activity help? Well, first, it would help for the concept of water activity to have a high enough profile that IMECHE would see fit to include it in their report. Sadly, they say only: “Moulds and fungi will quickly affect most foodstuffs if their (insert sound of screeching tires as brakes are applied) moisture content is too high” (crash). Technically, it’s true that moisture content affects mold and fungi growth, but only because it’s related to water activity. Note that 2 silos of wheat that are both at 12% moisture will behave differently if one of those silos was dried down to reach 12%, and the other one was wetted up (the one that was wetted up will mold because its water activity is too high).
To the extent that mold and yeast are problems for stored foods around the world, monitoring water activity can pinpoint when to harvest crops and when to leave them in the field. It can also predict which piles of grains or other commodities will spoil. It won’t tell you whether rodents are devouring your stored grain (a problem in many developing countries, says there report) but mold and yeast tend to be bigger problems than mice. This report is another indication of the importance of water in food, even if they did fumble one or two details. Please excuse me now while I polish off a plate-sized glazed danish – I’d hate to see it go to waste.