Dear Ecolog-Listers: A colleague who prefers to remain anonymous sent this message, re. use of water in chocolate production.
Apologies for potential duplicate emails. With gratefulness, Jorge *** Hi Jorge - Don't know of how much you this will be to you but I recently led a number of tutorials on water use and water conservation. Below is a link from a website we had students refer to when preparing for the tutorial. cheers Mark http://waterfootprint.org/en/resources/interactive-tools/product-gallery/ On average, cocoa beans have a water footprint of 20,000 litre/kg. Cocoa beans are first made into cocoa paste, with cocoa shells as rest product. About 97% of the total water footprint of cocoa beans is allocated to the cocoa paste that is derived from the beans; the rest is attributed to the by-products. One kilogram of cocoa beans gives about 800 gram of paste, so that the water footprint of cocoa paste is about 24,000 litre/kg. Cocoa paste is separated into cocoa butter and cocoa powder. About 66% of the water footprint of cocoa paste is allocated to the cocoa butter and 34% to the cocoa powder (this attribution is done based on the relative value of the two products). One kilogram cocoa paste gives 470 gram cocoa butter and 530 gram cocoa powder. On the basis of these figures we calculate that cocoa butter has a water footprint of 34,000 litre/kg and cocoa powder a water footprint of 15,600 litre/kg. When we assume that chocolate consists of 40% cocoa paste (with a water footprint of 24,000 litre/kg), 20% cocoa butter (34,000 litre/kg) and 40% cane sugar (1800 litre/kg), we can calculate that chocolate has a water footprint of about 17,000 litre/kg. A 100-gram chocolate bar costs 1700 litres. This is the global average; the figure in a specific case will depend on the precise origin of the cocoa and the production circumstances Publications 2011 Mekonnen, M.M. and Hoekstra, A.Y. (2011) The green, blue and grey water footprint of crops and derived crop products, *Hydrology and Earth System Sciences*, 15(5): 1577-1600. [image: download] <http://wfn.project-platforms.com/Reports/Mekonnen-Hoekstra-2011-WaterFootprintCrops.pdf>1.2 MB 2010 Mekonnen, M.M. and Hoekstra, A.Y. (2010) The green, blue and grey water footprint of crops and derived crop products, Value of Water Research Report Series No.47, UNESCO-IHE. Main Report Volume 1 [image: download] <http://wfn.project-platforms.com/Reports/Report47-WaterFootprintCrops-Vol1.pdf>1.2 MB Appendices Volume 2 [image: download] <http://wfn.project-platforms.com/Reports/Report47-WaterFootprintCrops-Vol2.pdf>9.7 MB -- Jorge A. Santiago-Blay, PhD blaypublishers.com 1. Positive experiences for authors of papers published in *LEB* http://blaypublishers.com/testimonials/ 2. Free examples of papers published in *LEB*: http://blaypublishers.com/category/previous-issues/. 3. *Guidelines for Authors* and page charges of *LEB*: http://blaypublishers.com/archives/ *.* 4. Want to subscribe to *LEB*? http://blaypublishers.com/subscriptions/ http://blayjorge.wordpress.com/ http://paleobiology.si.edu/staff/individuals/santiagoblay.cfm
