Talk:Cassava

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Contents 1 Two elements 2 Philippino tragedy 3 Indonesian fermented cassava 4 Suggested changes 5 Possible featured article nomination 6 Excessivie wikification 7 Pre-Columbian cassava usage 8 Chicha 9 Origin of Cassava 10 Different Languages? 11 Processing section pertaining to toxicity

[edit] Two elements

two elements in this article need clarification. First, the claim that it is now extinct in the wild. When did this happen? What is the evidence that this plant used to be wild? Is it possible that this particular species is domesticated (like corn)?

--> "Dicionário das Plantas Úteis do Brasil" (Pio Corrêa) states: (1) there are several wild species of Manihot, (2) that one form of the domesticated plant can be found growing spontaneously in the south of Brazil and in Paraguay, (3) the plant was domesticated before recorded history (pre-Columbian times) by native inhabitants.--Beanmf 14:52, 30 December 2005 (UTC)

The first external link contains an explanation. --Robert Merkel

Second, I do not believe that the plant contains cyanide. I believe it contains a chemical which, when oxidized, converts to prussic acid (or maybe cyanide) -- does someone know for sure? Also, not all varieties contain excessive ammounts of this chemical. That is, there is a difference between sweet and bitter manioc. I am not putting this information into the article myself because I do not know if this is two varieties of the same species, or two species. In any event, the article in its current state is a little misleading. Slrubenstein

--> "Plantas e Substâncias Vegetais Tóxicas e Medicinais" (F.C.Hoehne) states that there is a water-soluble glycoside which releases HCN (hydrogen cyanide or prussic acid). This book may be too old (1930's) to contain modern chemical evidence.--Beanmf 14:52, 30 December 2005 (UTC)

I believe the sweet and bitter are just different cultivars, not species. I've never heard of a cultagen 67.185.72.68 07:25, 17 December 2005 (UTC)a student of cassava

I do not think the first link provides an adequate explanation. Whether it does nor not, an encyclopedia should. The first link does, however, clarify that cassava does not contain cyanide and that not all varieties of cassava require processing; I have fixed this part up, SR

The sweet and bitter are just different cultivars. Some people say there is no wild cassava, but the debate rages. The plant contains linamarin and an some enzymes linamarase and hydroxynitrile lyase. Linamarase hydrolyzes the linamarin, making acetone cyanohydrin. Hydroxynitrile lyase breaks that down into acetone and cyanide. This breakdown occurs spontaneously when the pH is below 5 and the temperature is lower than 35 degrees Celsius, 95 degrees Fahrenheit. (UTC) EWU cassava student [1] Jan 2004 accessed Apr 2005

[edit] Philippino tragedy

Reuter announced at 12:47 AM ET of 3/12/05 that the cause of the death of the Philippino children was more likely organophosphate. Rat poisoning was found at the site but organophosphates are used as insecticide so it's unlikely that rat poison was the cause. As a Vietnamese physician who loves to eat cassava, I tend to agree with this presumption because I have never knew any massive poisoning by cassava and even improper preparation of the root would not leave enough linamarin to produce large amount of cyanide to cause the reported acute symptoms.

Thanks for the update. According to news reports at 3/12/05 there is still some uncertainty since the symptoms and facts could be explained by either theory, though the positive response of some of the victims to atropine suggests that you're probably correct. We'll know for sure when test results come in probably later today. --206.183.3.40 12:10, 13 Mar 2005 (UTC)

Update here. Testing confirmed that the Filipino tragedy wasn't due to wasn't cyanide from the cassava. It was due to pesticide. (That's pesticide that somehow ended up directly mixed into the food, rather than pesticide applied to a crop.) Singkong2005 05:01, 20 October 2005 (UTC)

[edit] Indonesian fermented cassava

I added a paragraph on Indonesian uses. Question is, does tape deserve its own article? If so I can translate the recipe from the Indo wiki article. Singkong2005 05:59, 20 October 2005 (UTC)

[edit] Suggested changes

The current text reads "may be called the "potato of the tropics". All known species and varieties are cultigens." Potatoes are already tropical in origin (Peru), so calling manioc the potato of the tropics only confuses the information; I suggest that this statement be eliminated. All known species of the species M.esculenta? It might be better to say that while there are several wild Manihot species, all varieties of M. Esculenta are cultigens. I have made these edits.--Beanmf 15:06, 30 December 2005 (UTC)

Can anyone help align the Processing to the left please?

Thanks for the changes. Indeed, "the potato of the tropics" sounds like the "the American Elvis" 8-) I have reordered the text (the head parag had become too heavy) and merged your text on flour processing with the existing parag; see if it is OK. All the best, Jorge Stolfi 17:06, 30 December 2005 (UTC)

[edit] Possible featured article nomination

This article is good. Have you considered a featured article nomination? I would do it, but I'm not willing to take on the responsibility of "making good-faith effort to address objections that are raised".

The article needs a lot of work. Cassava has major potential to spark rural development. [2] Aside from being human foodstuff, such uses as animal feed and industrial starch may be expanded through research and public-private partnerships. Cassava is a poor source of protein, especially compared to rice, and much protein is lost by peeling, but its protein quality is fairly good.[3] What protein source would ideally complement cassava (i.e., provide methionine) in regions where other sources of calories are hard to come by? Cassava root is a useful dietary source of calcium and phosphorus. Raw cassava root contains vitamin C, thiamine, riboflavin and nicotinic acid, but the extensive processing usually required for human consumption destroys much of this vitamin content. Use of cultivars with low levels of the cyanogenic glycosides linamarin and lotaustralin may make less processing safe, enable better use of the leaves (they are high in vitamin A) and increase use of cassava for animal feed, particularly poultry. However, what is the latest word on the long-term toxicity of low levels of HCN in animals, in humans and in the developing fetus? Marketing to the developed world can be enhanced by developing attractive food products aside from "tapioca". I'm not clear on whether cassava could be a good source of fibre, and non-digestible starch, prehaps with pro-biotic properties that could gain favor in diets for health-conscious consumers. We need some expert input here and broader perspective to make this a featured article, but cassava itself certainly deserves such honor. Myron 12:40, 21 February 2006 (UTC)

[edit] Excessivie wikification

Designation of certain wikilinks as "excessive" and removing them calls for explanation. I thought that everything possible gets wikified on its first appearance in a article so that an inquisitive visitor would be helped in clarifying uncertainty, in taking a quick glance at something not well-known or understood and in exploring novel topics. That certainly works for me as I read Wiki articles. Lots of articles have links when units of measure are introduced (as in mm or cm)... why make Cassava and exception? I'll revert if no timely justification is presented. Myron 18:12, 21 February 2006 (UTC)

[edit] Pre-Columbian cassava usage

The following text of the pre-columbian section reads:

[Cassava] was peeled, grated into flour and made into pancakes. Bitter varieties were detoxified by peeling and grating the root, straining the flour, then washing or boiling for 4-8 hours. The boiled cassava could be diluted to produce a drink called caxiri. Caxiri was often left to ferment for several days and even months. Alternatively, chewing and fermentation of cassava gruel produced cauim, a mild alcoholic beverage, which was consumed in vast quantities at parties and ceremonies. These practices are still current in many indian tribes.

I suspect that some of the information above is specific to the indigenous peoples of Brazil, perhaps only of certain regions. What was the general picture for the Americas? Where was Cassava cultivated? Were there regional variations in processing methods, dishes, drinks, etc?

Also, is caxiri a distinct beverage from cauim? The description sounds different (according to y sources, for cauim the root was cooked without grating, then chewed to add saliva enzymes, left to stand, then cooked, fermented, etc. Caxiri seems to be just cassava flour diluted in water.

Also, ist the bit about fermented caxiri correct? I thought that, without chewing, fermentation of cassava would just spoil it without producing ethanol.

All the best, Jorge Stolfi 04:13, 5 March 2006 (UTC)

[edit] Chicha

I see that someone changed the statement that Cassava is used along with beer in Peru to say that it is used along with chicha, which I know from nothing. Can someone verify this change? --Slashme 08:17, 4 August 2006 (UTC)

• Chicha is basically a type of beer. -THB

[edit] Origin of Cassava

Your introduction to the History of Cassava tells us that Cassava Originated in South America! However, we in Africa, having our indignous name to this plant (in Bete i.e. the Obudu area, it is called Ulogo) and still having several wild specie relatives of Cassava in the Cross-River State area, in Nigeria. We think that it is more reasonable to assume that being a tropical plant, this plant must have grown in most tropical areas of its own accord. How then could it have originated in South America? Could it be that several different specicies of this plant were originally local to different parts of the World?

[edit] Different Languages?

Is it necessary to list all these other languages? I was about to add the dutch name, but then I asked myself what the added value was for the English Wikipedia. I can understand adding yuca and manioc (which ar used in some English speaking countries), but why add the French and German name or the Haitian? Links to the other language wiki's should be enough, no?HichamVanborm 15:15, 26 October 2006 (UTC)

Maybe I'm not a typical user, but I was pleased to see the various translations as I was compiling a terminological record for this term. UrsusMaximus 12:21, 14 November 2006 (UTC)

I also found it very useful, since it is prevalent in many Caribbean islands, which have French, Dutch, and Spanish histories. Interestingly, no mention of where the word "cassava" comes from, since the Guarani (indigenous) word is closer to "manioc" I wonder why cassava became common usage. Jtone 16:16, 2 December 2006 (UTC)

[edit] Processing section pertaining to toxicity

The article states that one cannot eat manioc raw due to the presence of cyanogenic glucosides which convert to cyanide. While this may make it inadvisable and hazardous to eat manioc raw, it is not impossible. In certain countries in Africa it is eaten raw often, as a snack, with no side affects that could be discerned. This part should be changed, even if it is a little semantic, because it is nonetheless quite possible to eat manioc raw. Oneanddone 19:18, 1 December 2006 (UTC)