Please register ( or log-in ) to create and edit pages

User Tools

    Please register ( or log-in ) to create and edit pages
  • Register

Site Tools

Main Menu

Main menu
[ Click categories to expand ]

Other categories

For tests only

Also see:

Content Guidelinesplugin-autotooltip__plain plugin-autotooltip_bigContent guidelines

Ideas for new topics are always welcomed, from experts and non-experts alike - if you're not sure if they'll be accepted by other editors, put them in the 'Proposed content' section for approval. The easiest way to create a new page is to use the

Registrationplugin-autotooltip__plain plugin-autotooltip_bigRegistration

At present, only registered users can create and edit articles. The registration process is very straightforward. Just click the 'Register' link at the top right of any page.

After you've registered, you'll be able to login with your password at any time…

How to edit pagesplugin-autotooltip__plain plugin-autotooltip_bigEditing pages

Once you're logged in, a grey floating 'Tool' menu at the right hand side of the screen enables access to all the main 'Content Pages' for editing. (Note: Some pages, such as the site info etc. are locked)

Like most Wikis, the site doesn't use

Importance Ratingsplugin-autotooltip__plain plugin-autotooltip_bigImportance ratings

In a departure from the usual Wiki format, Wikenigma assigns 'Importance Ratings' to some pages.

The idea is to separate articles which are considered (by the editors) to cover exceptionally important unknown issues from those which (although also u…

Faqplugin-autotooltip__plain plugin-autotooltip_bigFrequently Asked Questions

Q. Why the weird syntax? A. Like most Wikis, the site doesn't use HTML for formatting (security reasons etc). A guide to the special syntax can be found here. Unfortunately it can be quite confusing at first - but there's now a new 'Visual …

Newsplugin-autotooltip__plain plugin-autotooltip_bigNews

[ newest at the top ]

• Oct 2020 : A milestone of 500 unknown articles has been reached.

• Aug 2020 : Currently (beta) testing the new 'WYSIWYG' (What You See Is What You Get) page editor. It greatly simplifies the editing process, avoiding the need to learn th…

Contactsplugin-autotooltip__plain plugin-autotooltip_bigContacts

Use this form to send a message to Wikenigma . . . [ * note: all fields must be completed ]

Legalplugin-autotooltip__plain plugin-autotooltip_bigLegal

Content in general

Please note that in common with other publicly editable wikis, this website is not responsible for content posted by the public. Nevertheless, the ongoing editing process should be able to remove unsuitable content in a reasonable time. If you…

538 unknowns listed

Wikenigma supports:

plugin-autotooltip__plain plugin-autotooltip_bigDonate to Wikenigma . . .

The best way to donate is by adding new original content !

That can either be by contributing to an existing article, or by creating a new page with an as-yet-unlisted 'Known Unknown'.

Any registered user can create content.

A-Z listing
rss / xml feed
sitemap file

Wikenigma - an Encyclopaedia of Unknowns Wikenigma - an Encyclopaedia of the Unknown Science


Current theory lists five main taste receptor categories : sweetness, bitterness, sourness, saltiness, and umami. source Wikipedia.

The physical mechanisms for detection of each of these main flavour types have been extensively investigated, and the corresponding tongue 'receptors' have (mostly) been identified.

A common misconception, however, is that any taste can therefore be described as a mixture of these elements (in the way that any visible colour can be formed by mixing red / green / blue).

“Defining taste as being limited to five categories suggests that taste is s simple sensation: this is not true.[…] How each taste is recognised, specificity by taste cells, and how tastes are coded and interpreted are still largely unknown.” source Flavor Chemistry and Technology, Second Edition, p.3, introduction

Even adding-in other taste sensations such as pungency, coolness, astringency,'metallicness', fattiness, and 'heartiness' (kokumi), the mechanisms by which highly complex mixtures of chemicals (e.g. chocolate) can be readily identified and classified are still a mystery.

Update Sep. 2016. A new study performed at Oregon State University suggests that a new 'basic taste' category might be added to the list -'Starchy'. Info. here at New Scientist. More accurately, the full paper describes experiments in which some people were able to taste glucose oligomer preparations (average degree of polymerization 7 and 14) - and a subsequent focus-group agreed to describe the taste as 'starchy'.

• Note regarding smell. The current estimates for the number of smells that humans can identify could be in the region of 1 Trillion. The figures are currently under dispute. See : The number of olfactory stimuli that humans can discriminate is still unknown eLife. 2015; 4: e08127.

    Share this page :