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DryCardTM — A Low-Cost Dryness Indicator for Dried Products

1 Department of Biological & Agricultural Engineering, University of California, Davis, One Shields Ave, Davis, CA 95616, USA.
2 Department of Plant Sciences, University of California, Davis, One Shields Ave, Davis, CA 95616, USA.
3 Prime Minister’s Office, Marketing Infrastructure, Value Addition and Rural Finance Support Programme, P.O. Box 14416, Arusha, Tanzania
4 Department of Plant Science and Crop Protection, University of Nairobi, University Way, Nairobi, Kenya.

Mycotoxin contamination of food and feed is a significant health hazard in humid areas of the world. Fungal development can be halted if the water activity of dried products is kept below 0.65. This preliminary study evaluates the color response and response time of a low-cost humidity indicator that estimates water activity. The DryCardTM has a consistent color response to relative humidity and its response time is fast enough to be used in practical situations for estimating water activity. The card comes with use instructions and it can be reused many times. It is a crucial tool to assist smallholder farmers and traders in ensuring their crops have been adequately dried.
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Keywords Aflatoxin; water activity; equilibrium relative humidity; grains; dried food

Citation: James F. Thompson, Michael S. Reid, Lucia Felix, Irwin Donis-Gonzalez, Bertha Mjawa, and Jane Ambuko. DryCardTM — A Low-Cost Dryness Indicator for Dried Products. AIMS Agriculture and Food, 2017, 2(4): 339-344. doi: 10.3934/agrfood.2017.4.339


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Copyright Info: 2017, James F. Thompson, et al., licensee AIMS Press. This is an open access article distributed under the terms of the Creative Commons Attribution Licese (http://creativecommons.org/licenses/by/4.0)

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