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Chaff
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<h2 id="etymology">Etymology</h2> Look up <i>chaff</i> or <i>glume</i> in Wiktionary, the free dictionary. <p>"Chaff" comes from <a href="/facts/Middle_English/dj1wHvwd">Middle English</a> <i>chaf</i>, from <a href="/facts/Old_English_language/9rsmQG2a">Old English</a> <i>ceaf</i>, related to <a href="/facts/Old_High_German/Vr3YC8sW">Old High German</a> <i><i>cheva</i></i>, "husk". </p> <h2 id="grain-chaff">Grain chaff</h2> <p>In <a href="/facts/Poaceae/q2CRK8q0">grasses</a> (including <a href="/facts/Cereal/ao2WcFdM">cereals</a> such as <a href="/facts/Rice/wvL1hBCz">rice</a>, <a href="/facts/Barley/GH7X2qtG">barley</a>, <a href="/facts/Oat/wn3vnCnT">oats</a>, and <a href="/facts/Wheat/lrk6HdV3">wheat</a>), the ripe seed is surrounded by thin, dry, scaly <a href="/facts/Bracts/pnMGNMdn">bracts</a> (called <a href="/facts/Glume/HVqQd6KV">glumes</a>, <a href="/facts/Lemma_(botany)/21A1twVk">lemmas</a>, and <a href="/facts/Palea_(botany)/21A1twVk">paleas</a>), forming a dry <a href="/facts/Husk/YAnnCM14">husk</a> (or hull) around the grain. Once it is removed, it is often referred to as chaff. </p><p>In wild cereals and in the primitive domesticated <a href="/facts/Einkorn/tQ3MtIJN">einkorn</a>,<a class="footnote-ref" id="fnref:2" href="#fn:2"><sup>2</sup></a> <a href="/facts/Emmer/htap49YH">emmer</a><a class="footnote-ref" id="fnref:3" href="#fn:3"><sup>3</sup></a> and <a href="/facts/Spelt/KeAWWpVv">spelt</a><a class="footnote-ref" id="fnref:4" href="#fn:4"><sup>4</sup></a> wheats, the husks enclose each seed tightly. Before the grain can be used, the husks must be removed. </p><p>The process of loosening the chaff from the grain so as to remove it is called "<a href="/facts/Threshing/YnrVYFnG">threshing</a>" before "<a href="/facts/Drying/hRBvapJN">drying</a>" – traditionally done by milling or pounding, making it finer like "<a href="/facts/Flour/dY1Lx5RQ">flour</a>". Separating remaining loose chaff from the grain is called "<a href="/facts/Winnowing/53xCFPLz">winnowing</a>" – traditionally done by repeatedly tossing the grain up into a light wind, which gradually blows the lighter chaff away. This method typically uses a broad, plate-shaped basket or similar receptacle to hold and collect the winnowed grain as it falls back down.<a class="footnote-ref" id="fnref:5" href="#fn:5"><sup>5</sup></a> </p><p>Domesticated grains such as <a href="/facts/Durum_wheat/rSKjJ1K3">durum</a> and <a href="/facts/Common_wheat/kmtLeodc">common wheat</a> have been bred to have chaff that is easily removed. These varieties are known as "free-threshing" or "naked".<a class="footnote-ref" id="fnref:6" href="#fn:6"><sup>6</sup></a><a class="footnote-ref" id="fnref:7" href="#fn:7"><sup>7</sup></a><a class="footnote-ref" id="fnref:8" href="#fn:8"><sup>8</sup></a> </p><p>Chaff should not be confused with <a href="/facts/Bran/BIdpgSwl">bran</a>, which is a finer, scaly material that is part of the grain itself. </p> <h2 id="straw-chaff">Straw chaff</h2> <p>Chaff is also made by chopping <a href="/facts/Straw/hqULAcwx">straw</a> (or sometimes coarse <a href="/facts/Hay/eKrHnGhl">hay</a>) into very short lengths, using a machine called a <a href="/facts/Chaff_cutter/4PEJSaw0">chaff cutter</a>. Like grain chaff, it is used as animal feed and is a way of making coarse fodder more palatable for livestock.<a class="footnote-ref" id="fnref:9" href="#fn:9"><sup>9</sup></a><a class="footnote-ref" id="fnref:10" href="#fn:10"><sup>10</sup></a><a class="footnote-ref" id="fnref:11" href="#fn:11"><sup>11</sup></a> </p> <h2 id="coffee-chaff">Coffee chaff</h2> <p><i>Coffee chaff</i> is produced from the so called <i>silverskin</i>, the thin inner-parchment layer on dried coffee beans, in the process of <a href="/facts/Coffee_grinder/6azR0oKn">grinding coffee</a> beans. </p> <h2 id="botany">Botany</h2> <p>In <a href="/facts/Botany/PaIRoxnb">botany</a>, chaff refers to the thin <a href="/facts/List_of_plant_morphology_terms/JwfMYURn">receptacular</a> <a href="/facts/Bracts/pnMGNMdn">bracts</a> of many species in the sunflower family <a href="/facts/Asteraceae/bouc6v8C">Asteraceae</a> and related families. They are modified scale-like <a href="/facts/Leaves/1m6wCNTg">leaves</a> surrounding single <a href="/facts/Floret/RjjcIGWp">florets</a> in the flower-head.<a class="footnote-ref" id="fnref:12" href="#fn:12"><sup>12</sup></a> </p> <h2 id="metaphor">Metaphor</h2> <p>Chaff as a waste product from grain processing leads to a <a href="/facts/Metaphor/xwsLaqJI">metaphorical</a> use of the term, to refer to something seen as worthless. In the <a href="/facts/Bible/SqkRTKCh">Bible</a>, such use is found in Job 13:25,<a class="footnote-ref" id="fnref:13" href="#fn:13"><sup>13</sup></a> Isaiah 33:11,<a class="footnote-ref" id="fnref:14" href="#fn:14"><sup>14</sup></a> Psalm 83:13-15,<a class="footnote-ref" id="fnref:15" href="#fn:15"><sup>15</sup></a> and other places. Chaff also lends its name to <a href="/facts/Chaff_(countermeasure)/V8TAMysf">a radar countermeasure</a>, composed of small particles dropped from an aircraft. </p> <h2 id="use">Use</h2> <p>Hungarian engineer László Schremmer has discovered that the use of chaff-based filters can reduce the <a href="/facts/Arsenic/k1c4f44D">arsenic</a> content of water to 3 microgram/litre. This is especially important in areas where the potable water is provided by filtering the water extracted from an underground <a href="/facts/Aquifer/UwG6ksdG">aquifer</a>.<a class="footnote-ref" id="fnref:16" href="#fn:16"><sup>16</sup></a> </p> <h2 id="see-also">See also</h2> <ul><li><a href="/facts/Awn_(botany)/5v3etQ2S">Awn (botany)</a></li> <li><a href="/facts/Bran/BIdpgSwl">Bran</a></li> <li><a href="/facts/Biomass/4VHjaya3">Biomass</a></li> <li><a href="/facts/Combine_harvester/g28hasTJ">Combine harvester</a></li> <li><a href="/facts/Rice_hulls/zhp9nNAq">Rice hulls</a></li> <li><a href="/facts/Rice_huller/4H943xlG">Rice huller</a></li> <li><a href="/facts/Sifting/LJBztC9f">Sifting</a></li></ul> <h2 id="references">References</h2> <ol> <li id="fn:1"><p>Daniel Jones (2006). Peter Roach; James Hartman; Jane Setter (eds.). Cambridge Pronouncing Dictionary. Cambridge University Press. <a href="#fnref:1" class="footnote-back-ref">↩</a></p></li> <li id="fn:2"><p>Potts, D. T. (1996) Mesopotamia Civilization: The Material Foundations Cornell University Press. p. 62. ISBN 0-8014-3339-8. <a href="/wiki/Cornell_University_Press" target="_blank">/wiki/Cornell_University_Press</a> <a href="#fnref:2" class="footnote-back-ref">↩</a></p></li> <li id="fn:3"><p>Nevo, Eviatar & A. B. Korol & A. Beiles & T. Fahima. (2002) Evolution of Wild Emmer and Wheat Improvement: Population Genetics, Genetic Resources, and Genome.... Springer. p. 8. ISBN 3-540-41750-8. <a href="/wiki/ISBN_(identifier)" target="_blank">/wiki/ISBN_(identifier)</a> <a href="#fnref:3" class="footnote-back-ref">↩</a></p></li> <li id="fn:4"><p>Vaughan, J. G. & P. A. Judd. (2003) The Oxford Book of Health Foods. Oxford University Press. p. 35. ISBN 0-19-850459-4. <a href="/wiki/Oxford_University_Press" target="_blank">/wiki/Oxford_University_Press</a> <a href="#fnref:4" class="footnote-back-ref">↩</a></p></li> <li id="fn:5"><p>"What Is Chaff: Learn How To Winnow Seeds From Chaff". Gardening Know How. 7 September 2019. Retrieved 2022-10-07. <a href="https://www.gardeningknowhow.com/edible/grains/general-grains/chaff-and-winnowing-information.htm" target="_blank">https://www.gardeningknowhow.com/edible/grains/general-grains/chaff-and-winnowing-information.htm</a> <a href="#fnref:5" class="footnote-back-ref">↩</a></p></li> <li id="fn:6"><p>"Cereals & Grains Association". www.cerealsgrains.org. Retrieved 2024-07-11. <a href="https://www.cerealsgrains.org/Pages/default.aspx" target="_blank">https://www.cerealsgrains.org/Pages/default.aspx</a> <a href="#fnref:6" class="footnote-back-ref">↩</a></p></li> <li id="fn:7"><p>Tzarfati, Raanan; Saranga, Yehoshua; Barak, Vered; Gopher, Avi; Korol, Abraham B.; Abbo, Shahal (September 2013). "Threshing efficiency as an incentive for rapid domestication of emmer wheat". Annals of Botany. 112 (5): 829–837. doi:10.1093/aob/mct148. ISSN 0305-7364. PMC 3747801. PMID 23884398. <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747801" target="_blank">https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3747801</a> <a href="#fnref:7" class="footnote-back-ref">↩</a></p></li> <li id="fn:8"><p>Watanabe, N. (2017-08-04). "Breeding opportunities for early, free-threshing and semi-dwarf Triticum monococcum L." Euphytica. 213 (8): 201. doi:10.1007/s10681-017-1987-0. ISSN 1573-5060. <a href="https://doi.org/10.1007/s10681-017-1987-0" target="_blank">https://doi.org/10.1007/s10681-017-1987-0</a> <a href="#fnref:8" class="footnote-back-ref">↩</a></p></li> <li id="fn:9"><p>"The Chaff cutter". Archived from the original on 2006-01-03. Retrieved 2005-09-06. <a href="https://web.archive.org/web/20060103083512/http://www.dulwichpicturegallery.org.uk/collection/search/display.aspx?irn=56" target="_blank">https://web.archive.org/web/20060103083512/http://www.dulwichpicturegallery.org.uk/collection/search/display.aspx?irn=56</a> <a href="#fnref:9" class="footnote-back-ref">↩</a></p></li> <li id="fn:10"><p>Cutting chaff by hand: detail of painting by David Teniers the Younger <a href="http://www.antiquefarmtools.info/" target="_blank">http://www.antiquefarmtools.info/</a> <a href="#fnref:10" class="footnote-back-ref">↩</a></p></li> <li id="fn:11"><p>A Victorian chaff cutter Archived March 21, 2008, at the Wayback Machine <a href="http://www.victorians.asp-host.co.uk/themes/agriculture/chaffcutterobj.htm" target="_blank">http://www.victorians.asp-host.co.uk/themes/agriculture/chaffcutterobj.htm</a> <a href="#fnref:11" class="footnote-back-ref">↩</a></p></li> <li id="fn:12"><p>Ronald Jones (25 March 2005). Plant Life of Kentucky: An Illustrated Guide to the Vascular Flora. University Press of Kentucky. pp. 751–. ISBN 0-8131-7194-6. <a href="0-8131-7194-6" target="_blank">0-8131-7194-6</a> <a href="#fnref:12" class="footnote-back-ref">↩</a></p></li> <li id="fn:13"><p>"Job 13:25 Would You frighten a windblown leaf? Would You chase after dry chaff?". biblehub.com. Retrieved 2022-10-07. <a href="https://biblehub.com/job/13-25.htm" target="_blank">https://biblehub.com/job/13-25.htm</a> <a href="#fnref:13" class="footnote-back-ref">↩</a></p></li> <li id="fn:14"><p>"Bible Gateway passage: Isaiah 33:11 - New International Version". Bible Gateway. Retrieved 2022-10-07. <a href="https://www.biblegateway.com/passage/?search=Isaiah%2033%3A11&version=NIV" target="_blank">https://www.biblegateway.com/passage/?search=Isaiah%2033%3A11&version=NIV</a> <a href="#fnref:14" class="footnote-back-ref">↩</a></p></li> <li id="fn:15"><p>"Bible Gateway passage: Psalm 83:13-15 - New International Version". Bible Gateway. Retrieved 2022-10-07. <a href="https://www.biblegateway.com/passage/?search=Psalm%2083%3A13-15&version=NIV" target="_blank">https://www.biblegateway.com/passage/?search=Psalm%2083%3A13-15&version=NIV</a> <a href="#fnref:15" class="footnote-back-ref">↩</a></p></li> <li id="fn:16"><p>Newspaper article Archived 2012-04-17 at the Wayback Machine (in Hungarian) published by Magyar Nemzet on April 15, 2012. <a href="http://mno.hu/gazdasag/szenzacios-magyar-talalmany-1068315" target="_blank">http://mno.hu/gazdasag/szenzacios-magyar-talalmany-1068315</a> <a href="#fnref:16" class="footnote-back-ref">↩</a></p></li> </ol>