{"id":7531,"date":"2023-11-27T18:44:55","date_gmt":"2023-11-27T17:44:55","guid":{"rendered":"https:\/\/agora.xtec.cat\/zer-riuiserra\/?p=7531"},"modified":"2024-10-02T18:19:55","modified_gmt":"2024-10-02T16:19:55","slug":"descobrim-els-llevats","status":"publish","type":"post","link":"https:\/\/agora.xtec.cat\/zer-riuiserra\/general\/descobrim-els-llevats\/","title":{"rendered":"DESCOBRIM ELS LLEVATS"},"content":{"rendered":"

A la classe dels grans ens hem endinsat en el m\u00f3n dels fongs. Hem descobert els fongs que no fan bolets. Els primers que vam observar van ser observar les floridures que s\u00f3n fongs microsc\u00f2pics que les podem veure a simple vista perqu\u00e8 son organismes multicel\u00b7lulars.
\nAix\u00ed va ser la primera descoberta que vam fer al sostre de la biblioteca i a les parets de l’escala. Fins i tot ho vam
\nveure als llibres!. La humitat despr\u00e9s de les filtracions dels aiguats del setembre van permetre el desenvolupament d’aquests fongs.
\nEl segon grup de fongs que hem treballat han estat els llevats, especialment els que intervenen en l’elaboraci\u00f3 del pa. Ens vam plantejar una s\u00e8rie de preguntes pr\u00e8vies a partir de la imatge d’una llesca de pa: perqu\u00e8 el pa t\u00e9 forats, de que deuen estar plens aquests forats i de qu\u00e8 deu estar fet el pa per tenir aquets forats.
\nLa nostra tasca de la setmana de la Ci\u00e8ncia acabava de comen\u00e7ar.
\nPer descobrir-ho que millor que visitar el forn de pa Miquel Cortijos del poble.
\nDurant la visita, Miquel ens va explicar com el llevat \u00e9s un organisme viu que necessita una s\u00e8rie de condicions \u00f2ptimes d’humitat i una temperatura adequada. Durant el proc\u00e9s de fermentaci\u00f3, el llevat transforma els sucres presents a la farina.
\nEn aquest proc\u00e9s els milers de microorganismes del llevat desprenen com a residus bombolles de di\u00f2xid de carboni i alcohol. Les bombolles de di\u00f2xid de carboni s\u00f3n les que fan que la massa de pa s’infli i quedi esponjosa, mentre que l’alcohol s’evapora durant la cocci\u00f3. Ja hav\u00edem trobat resposta a les preguntes que ens hav\u00edem plantejat!
\nEns van endur cap a classe una bossa massa de pa amb llevat, i una altra sense llevat El nostre proc\u00e9s d’investigaci\u00f3 s’anava ampliant!.
\nMiquel tamb\u00e9 ens va parlar de Louis Pasteur. Investigant a classe, vam con\u00e8ixer que els seus treballs van permetre explicar cient\u00edficament els fen\u00f2mens de la fermentaci\u00f3, l’any 1857. Per fer-ho, va utilitzar un instrument clau: el microscopi. Aix\u00ed \u00e9s com es van descobrir que els llevats s\u00f3n uns petits fongs, unicel\u00b7lulars, de forma ovalada o rodona i d\u2019un di\u00e0metre d\u2019entre 3 i 12 micres, de l\u2019esp\u00e8cie Saccharomyces cerevisiae.<\/p>\n\n\n\n\n
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 <\/p>\n","protected":false},"excerpt":{"rendered":"

Els i les grans ens hem endinsat en el m\u00f3n dels fongs, i hem descobert que n’hi ha que no fan bolets.
\nS\u00f3n els llevats que intervenen en l’elaboraci\u00f3 del pa.<\/p>\n","protected":false},"author":10,"featured_media":7532,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"_bbp_topic_count":0,"_bbp_reply_count":0,"_bbp_total_topic_count":0,"_bbp_total_reply_count":0,"_bbp_voice_count":0,"_bbp_anonymous_reply_count":0,"_bbp_topic_count_hidden":0,"_bbp_reply_count_hidden":0,"_bbp_forum_subforum_count":0,"site-sidebar-layout":"default","site-content-layout":"","ast-site-content-layout":"","site-content-style":"default","site-sidebar-style":"default","ast-global-header-display":"","ast-banner-title-visibility":"","ast-main-header-display":"","ast-hfb-above-header-display":"","ast-hfb-below-header-display":"","ast-hfb-mobile-header-display":"","site-post-title":"","ast-breadcrumbs-content":"","ast-featured-img":"","footer-sml-layout":"","theme-transparent-header-meta":"","adv-header-id-meta":"","stick-header-meta":"","header-above-stick-meta":"","header-main-stick-meta":"","header-below-stick-meta":"","astra-migrate-meta-layouts":"default","ast-page-background-enabled":"default","ast-page-background-meta":{"desktop":{"background-color":"var(--ast-global-color-4)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"ast-content-background-meta":{"desktop":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"tablet":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""},"mobile":{"background-color":"var(--ast-global-color-5)","background-image":"","background-repeat":"repeat","background-position":"center center","background-size":"auto","background-attachment":"scroll","background-type":"","background-media":"","overlay-type":"","overlay-color":"","overlay-opacity":"","overlay-gradient":""}},"footnotes":""},"categories":[94,156,157,149,1,29],"tags":[],"class_list":["post-7531","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-blocs-zer","category-cicle-mitja-aldover","category-cicle-superior-aldover","category-escola-aldover-2","category-general","category-portada"],"post_mailing_queue_ids":[],"_links":{"self":[{"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/posts\/7531","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/users\/10"}],"replies":[{"embeddable":true,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/comments?post=7531"}],"version-history":[{"count":6,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/posts\/7531\/revisions"}],"predecessor-version":[{"id":8133,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/posts\/7531\/revisions\/8133"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/media\/7532"}],"wp:attachment":[{"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/media?parent=7531"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/categories?post=7531"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/agora.xtec.cat\/zer-riuiserra\/wp-json\/wp\/v2\/tags?post=7531"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}