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Coffee for Justice: Chemistry in service to small-holder coffee farmers ACS Science and Human Rights Webinar presented October 9, 2012 Susan C. Jackels Seattle University. Telling the story of collaboration with Nicaraguan small-holder coffee farmers. The “Coffee Crisis” of 2001
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Coffee for Justice:Chemistry in service to small-holder coffee farmersACS Science and Human Rights WebinarpresentedOctober 9, 2012 Susan C. JackelsSeattle University
Telling the story of collaboration with Nicaraguan small-holder coffee farmers • The “Coffee Crisis” of 2001 • Nicaraguan Farmers’ response • Involvement in coffee quality improvement with farmers, using chemistry
Coffee Crisis: Volatility in the Price of Coffee on the World Market “Coffee Crisis” N. Luttinger and G. Dicum, “The Coffee Book,” Norton, 2006
Response to the Coffee Crisis in Nicaragua since 2001 • Small holder producers have strengthened cooperative organizations in order to: • Improve coffee quality (hope for access to specialty quality market) • Gain certification (Fair Trade and Organic) • Gain access to international markets • International relief and development organizations began providing assistance. (USAID, Catholic Relief Services, others) • In 2002, I became involved through association with ISJACHEM, University of Central America Managua and Catholic Relief Services
Why improve coffee quality at some expense to quantity? • Gain access to specialty market (quality must be higher than 80 on a 100 point scale so the global buyers get interested) • Hope for a relationship with a buyer that persists year-to-year • Direct trade can get a good price but must have a connection and good quality
Why improve coffee quality at some expense to quantity? • Organic/Fair Trade market: producers still can’t find a buyer for all organic coffee (our coffee coops this year sold 70% of their coffee on conventional market) • Small differential between organic and conventional market prices (2012)
A research /service project in service to Nicaraguan small-holder coffee producers • The goal is to help producers get out of the Coffee Crisis by improving their coffee so it can be sold on the Organic /Fair Trade or Specialty market (or direct trade).
Partner Organizations • Catholic Relief Services Nicaragua/ Caritas Matagalpa • Nicaraguan farmer coops CECOSEMAC and ADDAC • University of Central America Managua • National Science Foundation • Seattle U • UW Bothell • Winds of Peace • MJ Murdock Charitable Trust
Nicaragua Locations of Cooperatives We were connected with these coffee farm cooperatives through Catholic Relief Services
First and foremost, make good relationship with the community
Focus groups: We asked the farmers for their questions • What is the effect of over-fermentation on coffee quality? • How can fermentation be controlled to optimize coffee quality and maintain consistency?
What did you say? Fermentation in coffee processing? Coffee Cherry Anatomy Mucilage Layer removed by fermentation after outer skin and pulp are removed mechanically.
How can we answer the farmers’ question about over fermentation and whether it affects their coffee quality?We began by doing a field study on the farms to find out changes happening during coffee fermentation.
A field study of coffee fermentation on small farms in Matagalpa in 2004 SC Jackels and CF Jackels, Journal of Food Science, 2005, Vol. 70, pages C321 – C325.
All batches were ready to wash at the same pH. pH profiles of coffee fermentation
Conclusions from field study • The regular pattern of pH change during fermentation may be useful for producers. • The results provide the basis for a simple method to control fermentation on the farm by monitoring pH. • Necessary to determine the relationship between roasted coffee quality in the cup and fermentation time (over fermentation).
2006 controlled fermentation experiments • On each of eleven days divided one large batch of pulped coffee into six small buckets for fermentation • Each day: Fermentation stopped at three different pH ranges • “Cupped” the coffee to determine quality Does a relationship exist between fermentation pH at time of washing and coffee quality?
Three pH ranges each day • Wash 2 buckets in each pH range: • Range 1: pH = 4.5-4.8 • Range 2: pH = 4.1-4.4 • Range 3: pH = 4.0-3.6 Ph during the time of fermentation 1 2 3 Time
pH monitoring and washing Stephanie Kleven and Roberto Rivas, washing coffee. Stephanie Kleven, testing in lab.
Coffee Quality by Cupping in Laboratories • Scores on 66 coffee batches are in the range 75- 88 • “Good coffee, but not outstanding” • Are there significant changes with systematic over fermentation? Sol Café Laboratory Cupper with international reputation
Cupping Results Qualities: Fragrance and Aroma Acidity Flavor Body After-taste Balance Ranges: 90 – 100 (excellent); 80 – 89 (very good); 70 – 79 (commercial); 60 – 69 (poor); <60 (not acceptable)
Paired sample t-test Do the averages differ significantly? One-tail probability
Quality changes of individual paired samples Wilcoxon Signed Rank Test (one-tail): Range 1 2 (p = 0.043) Range 1 3 (p = 0.055)
Controlled fermentation experiments: Conclusions Does a relationship exist between fermentation pH at time of washing and coffee quality? • Weak relationship is observed: lower values of pHterm (over-fermentation) correspond to reduced coffee quality: -1.5 point change in quality for pH change of approximately -0.5 units. • A more powerful study, with more replicates would strengthen this conclusion. S. Jackels, C. Jackels, C. Vallejos, S. Kleven, R. Rivas and S. Fraser-Dauphinee, Proceedings of the 21st ASIC (Association Scientifique Internationale du Café) Meeting 2006, pp. 434 – 442.
Can producers themselves use pH measurements to improve coffee quality through “fermentation optimization”? Fermentation optimization by coffee producers 100 kits for small farmers: pH paper, watch, instructions, materials
Treatment applied by producers • Before:Measure pH at time of washing coffee, making no change from usual routine. Then submit a sample for drying, roasting and cupping. • Make changes in fermentation to optimize. • After:Measure pH at time of washing an optimized batch. Then submit a sample for drying, roasting and cupping.
The producers’ changes in pH and fermentation time were correlated Fermentation Time versus pH: “After” – “Before” Spearman rank correlation: rho = -0.341, N = 69 Inverse Correlation is significant (P = 0.004)
Did the coffee quality improve?Average Cup Scores All Samples Included Damaged Samples Removed
Answer: Maybe • Farmers successfully controlled fermentation with kits • No statistically significant change in quality, however. • Crop quality problem: Before-step was mid-harvest at peak of quality, After-step was end of harvest when quality diminished. Was the fermentation optimized by coffee producers? S. Jackels and C. Jackels, Proceedings of the 21st ASIC (Association Scientifique Internationale du Café) Meeting (Montpelier) 2006, pp. 434 – 442 (2006)
Cup scores by cooperative 2012 harvest: all of these cooperatives were in the 82 – 83 range.
Social Analysis: What did the coffee producers learn from us? • Increased awareness of the importance of quality control and potential for improvement • Increased involvement and interest of the children • Higher morale and more hope for the future
2009 Engineering project to build a coffee mill M.D. Marsolek, J.T. Alcantara, P. Cummings, L. Quintero, M. Wynne, C. Vallejos, C.F. Jackels, S.C. Jackels, International Journal for Service Learning in Engineering, June 2012.
Acknowledgements to International Scientific Teams • Faculty • Prof. Susan Jackels, Seattle University (USA) • Prof. Charles Jackels, Univ. of Washington Bothell (USA) • Prof. Carlos Vallejos, Univ. of Central America Managua (Nicaragua) • Prof. Cipriano Lopez, Univ. of Central America Managua (Nicaragua) • Prof. Michael Marsolek, Seattle University (USA) • Students • Seattle University: Stephanie Kleven, Jack Chacon, Joshua Alcantara, Patrick Cummings, Luis Quintero, Michael Wynne, Angelica Omaiye, Zachary Kamine, Kathleen Bacarro, Czarina Franco, Diana Heaney, Spencer Ubben, Stella Navia, Jody Cook, Britt Mueller, Tam Pham, Ivon Octavia, Jessica Angginasah, Fera Widjaja, Amy Sly, Kerina Powell • University of British Columbia (Canada): Scott Fraser-Dauphinee • University of Central America Managua (Nicaragua): Roberto Rivas, Diana Zelaya, Gema Medina, Maria Auxiliadora Castillo, Ervin Garcia • Farmers and NGO’s • Coffee farms and families of Matagalpa, Nicaragua • CECOSEMAC and ADDAC Cooperatives and Caritas Matagalpa • Catholic Relief Services/Nicaragua
Acknowledgements for Support • US National Science Foundation (CHE-0512867) • Engineers Without Borders • Tetra Tech, Inc. • Winds of Peace Foundation • MJ Murdock Charitable Trust • Seattle University • University of Central America Managua • Catholic Relief Services/Nicaragua