La Bolsa de Café, Buenos Aires, Argentina 2008
©EOP
The interconnectedness of water supply, food supply and the human population was the basic idea prompting this set of courses, and I hope at least a few OLLI members will enroll in all three even if each course is designed to stand independently. The topics of three courses are interdependent in many ways, but we are often inclined to ignore those connections. Over the past few days I have been doing some research on the connections between water supply and food production, and I have discovered a true cornucopia of material (pun intended).
We need water directly for hygiene and sanitation, but by far the largest human use of water is for agriculture and the production and processing of food. Each food unit we consume is composed of various inputs of which water is a crucial one. Even the crops most tolerant of aridity demand at least a little water to grow and produce food. Many foodstuffs are ravenous consumers of water requiring hundreds or even thousands of liters of water for each kilogram or liter of product. That is a subject we shall look at in some detail in the course and perhaps in future blog postings. Today I would like to introduce the water demands just one thing many people consume regularly, coffee.
Coffee is not really food, and with a little pain - a couple of days of caffeine deprivation headaches - most of us could probably stop drinking it (though I really like the taste of good coffee). Coffee is an obvious user of water, for each cup brewed requires us to draw water from the tap. That single cup of coffee requires not just the cup (125 ml) we put in the coffee maker but a total of 140 liters of water! Not so obvious when we brew the pot is the large amount of water needed to grow, process, and transport the beans to us as well as the water needed to produce the electricity, dispose of the waste, etc. The Dutch, who are known for their fine coffee and their coffee drinking tradition, have studied the issue and in a paper titled "The water needed to have the Dutch drink coffee" two Dutch scholars have outlined the demand for water related to coffee drinking in the Netherlands, the water footprint of Dutch coffee. It makes for fascinating and thought provoking reading!
By comparison to most meat products, our liquid refreshments, including coffee, tea (30 liters per cup) , and beer (75 liters per 250 ml glass) demand fairly modest quantities of water. The Water Footprint Network, operated from the University of Twente in the Netherlands in cooperation with UNESCO,offers a great set of webpages and downloadable publications on the water demands of lots of different foods and other products and the issue of water footprints.
By comparison to most meat products, our liquid refreshments, including coffee, tea (30 liters per cup) , and beer (75 liters per 250 ml glass) demand fairly modest quantities of water. The Water Footprint Network, operated from the University of Twente in the Netherlands in cooperation with UNESCO,offers a great set of webpages and downloadable publications on the water demands of lots of different foods and other products and the issue of water footprints.
