{"id":10801,"date":"2026-07-10T07:29:53","date_gmt":"2026-07-10T07:29:53","guid":{"rendered":"https:\/\/rafsol.eu\/oxidative-stability-of-frying-fat-how-to-effectively-extend-fat-life-in-a-frying-operation\/"},"modified":"2026-08-15T20:11:34","modified_gmt":"2026-08-15T20:11:34","slug":"oxidative-stability-of-frying-fat-how-to-effectively-extend-fat-life-in-a-frying-operation","status":"publish","type":"post","link":"https:\/\/rafsol.eu\/en\/oxidative-stability-of-frying-fat-how-to-effectively-extend-fat-life-in-a-frying-operation\/","title":{"rendered":"Oxidative stability of frying fat \u2013 how to effectively extend fat life in a frying operation"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"10801\" class=\"elementor elementor-10801 elementor-10600\">\n\t\t\t\t<div class=\"elementor-element elementor-element-4974f66 e-flex e-con-boxed e-con e-parent\" data-id=\"4974f66\" data-element_type=\"container\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t<div class=\"elementor-element elementor-element-f19506e elementor-widget elementor-widget-text-editor\" data-id=\"f19506e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-size: 18px;\"><b>The oxidative stability of frying fat<\/b> determines how many frying cycles the fat will withstand before it loses its technological properties and becomes a source of quality problems. In professional frying operations, catering establishments and production lines, this is one of the key parameters directly affecting operating costs and the safety of the final product.<\/span><\/p>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-a83653f e-con-full e-flex e-con e-child\" data-id=\"a83653f\" data-element_type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-3a2c221 elementor-hidden-tablet elementor-hidden-mobile aleft elementor-widget-image-box wgl-image-box wgl-view-default button-left elementor-invisible elementor-widget elementor-widget-wgl-infobox\" data-id=\"3a2c221\" data-element_type=\"widget\" data-settings=\"{&quot;_animation&quot;:&quot;wgl_fade_up&quot;,&quot;_animation_delay&quot;:100}\" data-widget_type=\"wgl-infobox.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"wgl-infobox_bg_wrapper\"><\/div><div class=\"wgl-infobox\"><a class=\"wgl-infobox__link\" href=\"https:\/\/rafsol.eu\/en\/offer\/frying-fats\/\"><\/a><div class=\"wgl-infobox_wrapper wgl-layout-right\"><div class=\"wgl-infobox-media_wrapper\"><span class=\"media-wrapper img-wrapper\"><span class=\"wgl-image-box_img\"><span ><img fetchpriority=\"high\" decoding=\"async\" width=\"300\" height=\"214\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/frytury-do-smazenia-ikonka-2-300x214.jpg\" class=\"attachment-medium size-medium wp-image-6849\" alt=\"Frytury do sma\u017cenia\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/frytury-do-smazenia-ikonka-2-300x214.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/frytury-do-smazenia-ikonka-2.jpg 350w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/span><\/span><\/span><\/div><div class=\"content_wrapper\"><div class=\"wgl-infobox-title_wrapper\"><h3 class=\"wgl-infobox_title\"><span class=\"wgl-infobox_title-idle\"><span class=\"elementor-repeater-item-3e07555\">Frying fats<\/span><\/span><\/h3><\/div><div class=\"wgl-button-wrapper\"><div  class=\"wgl-infobox_button wgl-button \"><div class=\"button__content\"><div class=\"icon-wrapper\"><span class=\"wgl-icon\"> <span class=\"read-more-icon read-more-svg\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"18\" height=\"16\" viewBox=\"0 0 18 16\"><path fill-rule=\"evenodd\" clip-rule=\"evenodd\" d=\"M0 7.99999C0 7.70162 0.118527 7.41547 0.329505 7.20449C0.540484 6.99351 0.826631 6.87499 1.125 6.87499H14.1593L9.3285 2.04649C9.11726 1.83524 8.99858 1.54873 8.99858 1.24999C8.99858 0.951242 9.11726 0.664732 9.3285 0.453487C9.53974 0.242242 9.82625 0.123566 10.125 0.123566C10.4237 0.123566 10.7103 0.242242 10.9215 0.453487L17.6715 7.20349C17.7763 7.30799 17.8594 7.43213 17.9161 7.56881C17.9728 7.70549 18.002 7.85201 18.002 7.99999C18.002 8.14796 17.9728 8.29449 17.9161 8.43116C17.8594 8.56784 17.7763 8.69199 17.6715 8.79649L10.9215 15.5465C10.7103 15.7577 10.4237 15.8764 10.125 15.8764C9.82625 15.8764 9.53974 15.7577 9.3285 15.5465C9.11726 15.3352 8.99858 15.0487 8.99858 14.75C8.99858 14.4512 9.11726 14.1647 9.3285 13.9535L14.1593 9.12499H1.125C0.826631 9.12499 0.540484 9.00646 0.329505 8.79548C0.118527 8.58451 0 8.29836 0 7.99999Z\"><\/path><\/svg><\/span><\/span><\/div><span class=\"button__text\">View offer<\/span><\/div><\/div><\/div><\/div><\/div><\/div>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-940c1d7 elementor-hidden-desktop aleft elementor-widget-image-box wgl-image-box wgl-view-default button-left elementor-invisible elementor-widget elementor-widget-wgl-infobox\" data-id=\"940c1d7\" data-element_type=\"widget\" data-settings=\"{&quot;_animation&quot;:&quot;wgl_fade_up&quot;,&quot;_animation_delay&quot;:100}\" data-widget_type=\"wgl-infobox.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"wgl-infobox_bg_wrapper\"><\/div><div class=\"wgl-infobox\"><a class=\"wgl-infobox__link\" href=\"https:\/\/rafsol.eu\/en\/offer\/frying-fats\/\"><\/a><div class=\"wgl-infobox_wrapper wgl-layout-top\"><div class=\"wgl-infobox-media_wrapper\"><span class=\"media-wrapper img-wrapper\"><span class=\"wgl-image-box_img\"><span ><img fetchpriority=\"high\" decoding=\"async\" width=\"300\" height=\"214\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/frytury-do-smazenia-ikonka-2-300x214.jpg\" class=\"attachment-medium size-medium wp-image-6849\" alt=\"Frytury do sma\u017cenia\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/frytury-do-smazenia-ikonka-2-300x214.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/frytury-do-smazenia-ikonka-2.jpg 350w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/span><\/span><\/span><\/div><div class=\"content_wrapper\"><div class=\"wgl-infobox-title_wrapper\"><h3 class=\"wgl-infobox_title\"><span class=\"wgl-infobox_title-idle\"><span class=\"elementor-repeater-item-3e07555\">Frying fats<\/span><\/span><\/h3><\/div><div class=\"wgl-button-wrapper\"><div  class=\"wgl-infobox_button wgl-button \"><div class=\"button__content\"><div class=\"icon-wrapper\"><span class=\"wgl-icon\"> <span class=\"read-more-icon read-more-svg\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"18\" height=\"16\" viewBox=\"0 0 18 16\"><path fill-rule=\"evenodd\" clip-rule=\"evenodd\" d=\"M0 7.99999C0 7.70162 0.118527 7.41547 0.329505 7.20449C0.540484 6.99351 0.826631 6.87499 1.125 6.87499H14.1593L9.3285 2.04649C9.11726 1.83524 8.99858 1.54873 8.99858 1.24999C8.99858 0.951242 9.11726 0.664732 9.3285 0.453487C9.53974 0.242242 9.82625 0.123566 10.125 0.123566C10.4237 0.123566 10.7103 0.242242 10.9215 0.453487L17.6715 7.20349C17.7763 7.30799 17.8594 7.43213 17.9161 7.56881C17.9728 7.70549 18.002 7.85201 18.002 7.99999C18.002 8.14796 17.9728 8.29449 17.9161 8.43116C17.8594 8.56784 17.7763 8.69199 17.6715 8.79649L10.9215 15.5465C10.7103 15.7577 10.4237 15.8764 10.125 15.8764C9.82625 15.8764 9.53974 15.7577 9.3285 15.5465C9.11726 15.3352 8.99858 15.0487 8.99858 14.75C8.99858 14.4512 9.11726 14.1647 9.3285 13.9535L14.1593 9.12499H1.125C0.826631 9.12499 0.540484 9.00646 0.329505 8.79548C0.118527 8.58451 0 8.29836 0 7.99999Z\"><\/path><\/svg><\/span><\/span><\/div><span class=\"button__text\">View offer<\/span><\/div><\/div><\/div><\/div><\/div><\/div>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-2e0244c e-con-full e-flex e-con e-child\" data-id=\"2e0244c\" data-element_type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-2d47ea6 elementor-hidden-tablet elementor-hidden-mobile aleft elementor-widget-image-box wgl-image-box wgl-view-default button-left elementor-invisible elementor-widget elementor-widget-wgl-infobox\" data-id=\"2d47ea6\" data-element_type=\"widget\" data-settings=\"{&quot;_animation&quot;:&quot;wgl_fade_up&quot;,&quot;_animation_delay&quot;:100}\" data-widget_type=\"wgl-infobox.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"wgl-infobox_bg_wrapper\"><\/div><div class=\"wgl-infobox\"><a class=\"wgl-infobox__link\" href=\"https:\/\/rafsol.eu\/en\/offer\/oils-for-frying-and-salads\/\"><\/a><div class=\"wgl-infobox_wrapper wgl-layout-right\"><div class=\"wgl-infobox-media_wrapper\"><span class=\"media-wrapper img-wrapper\"><span class=\"wgl-image-box_img\"><span ><img decoding=\"async\" width=\"300\" height=\"214\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/oleje-do-smazenia-salatek-ikonka-2-300x214.jpg\" class=\"attachment-medium size-medium wp-image-6850\" alt=\"Oleje do sma\u017cenia i sa\u0142atek dla produkcji spo\u017cywczej\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/oleje-do-smazenia-salatek-ikonka-2-300x214.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/oleje-do-smazenia-salatek-ikonka-2.jpg 350w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/span><\/span><\/span><\/div><div class=\"content_wrapper\"><div class=\"wgl-infobox-title_wrapper\"><h3 class=\"wgl-infobox_title\"><span class=\"wgl-infobox_title-idle\"><span class=\"elementor-repeater-item-3e07555\">Oils for frying and salads<\/span><\/span><\/h3><\/div><div class=\"wgl-button-wrapper\"><div  class=\"wgl-infobox_button wgl-button \"><div class=\"button__content\"><div class=\"icon-wrapper\"><span class=\"wgl-icon\"> <span class=\"read-more-icon read-more-svg\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"18\" height=\"16\" viewBox=\"0 0 18 16\"><path fill-rule=\"evenodd\" clip-rule=\"evenodd\" d=\"M0 7.99999C0 7.70162 0.118527 7.41547 0.329505 7.20449C0.540484 6.99351 0.826631 6.87499 1.125 6.87499H14.1593L9.3285 2.04649C9.11726 1.83524 8.99858 1.54873 8.99858 1.24999C8.99858 0.951242 9.11726 0.664732 9.3285 0.453487C9.53974 0.242242 9.82625 0.123566 10.125 0.123566C10.4237 0.123566 10.7103 0.242242 10.9215 0.453487L17.6715 7.20349C17.7763 7.30799 17.8594 7.43213 17.9161 7.56881C17.9728 7.70549 18.002 7.85201 18.002 7.99999C18.002 8.14796 17.9728 8.29449 17.9161 8.43116C17.8594 8.56784 17.7763 8.69199 17.6715 8.79649L10.9215 15.5465C10.7103 15.7577 10.4237 15.8764 10.125 15.8764C9.82625 15.8764 9.53974 15.7577 9.3285 15.5465C9.11726 15.3352 8.99858 15.0487 8.99858 14.75C8.99858 14.4512 9.11726 14.1647 9.3285 13.9535L14.1593 9.12499H1.125C0.826631 9.12499 0.540484 9.00646 0.329505 8.79548C0.118527 8.58451 0 8.29836 0 7.99999Z\"><\/path><\/svg><\/span><\/span><\/div><span class=\"button__text\">View offer<\/span><\/div><\/div><\/div><\/div><\/div><\/div>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f4bf496 elementor-hidden-desktop aleft elementor-widget-image-box wgl-image-box wgl-view-default button-left elementor-invisible elementor-widget elementor-widget-wgl-infobox\" data-id=\"f4bf496\" data-element_type=\"widget\" data-settings=\"{&quot;_animation&quot;:&quot;wgl_fade_up&quot;,&quot;_animation_delay&quot;:100}\" data-widget_type=\"wgl-infobox.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<div class=\"wgl-infobox_bg_wrapper\"><\/div><div class=\"wgl-infobox\"><a class=\"wgl-infobox__link\" href=\"https:\/\/rafsol.eu\/en\/offer\/oils-for-frying-and-salads\/\"><\/a><div class=\"wgl-infobox_wrapper wgl-layout-top\"><div class=\"wgl-infobox-media_wrapper\"><span class=\"media-wrapper img-wrapper\"><span class=\"wgl-image-box_img\"><span ><img decoding=\"async\" width=\"300\" height=\"214\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/oleje-do-smazenia-salatek-ikonka-2-300x214.jpg\" class=\"attachment-medium size-medium wp-image-6850\" alt=\"Oleje do sma\u017cenia i sa\u0142atek dla produkcji spo\u017cywczej\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/oleje-do-smazenia-salatek-ikonka-2-300x214.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/11\/oleje-do-smazenia-salatek-ikonka-2.jpg 350w\" sizes=\"(max-width: 300px) 100vw, 300px\" \/><\/span><\/span><\/span><\/div><div class=\"content_wrapper\"><div class=\"wgl-infobox-title_wrapper\"><h3 class=\"wgl-infobox_title\"><span class=\"wgl-infobox_title-idle\"><span class=\"elementor-repeater-item-3e07555\">Oils for frying and salads<\/span><\/span><\/h3><\/div><div class=\"wgl-button-wrapper\"><div  class=\"wgl-infobox_button wgl-button \"><div class=\"button__content\"><div class=\"icon-wrapper\"><span class=\"wgl-icon\"> <span class=\"read-more-icon read-more-svg\"><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" width=\"18\" height=\"16\" viewBox=\"0 0 18 16\"><path fill-rule=\"evenodd\" clip-rule=\"evenodd\" d=\"M0 7.99999C0 7.70162 0.118527 7.41547 0.329505 7.20449C0.540484 6.99351 0.826631 6.87499 1.125 6.87499H14.1593L9.3285 2.04649C9.11726 1.83524 8.99858 1.54873 8.99858 1.24999C8.99858 0.951242 9.11726 0.664732 9.3285 0.453487C9.53974 0.242242 9.82625 0.123566 10.125 0.123566C10.4237 0.123566 10.7103 0.242242 10.9215 0.453487L17.6715 7.20349C17.7763 7.30799 17.8594 7.43213 17.9161 7.56881C17.9728 7.70549 18.002 7.85201 18.002 7.99999C18.002 8.14796 17.9728 8.29449 17.9161 8.43116C17.8594 8.56784 17.7763 8.69199 17.6715 8.79649L10.9215 15.5465C10.7103 15.7577 10.4237 15.8764 10.125 15.8764C9.82625 15.8764 9.53974 15.7577 9.3285 15.5465C9.11726 15.3352 8.99858 15.0487 8.99858 14.75C8.99858 14.4512 9.11726 14.1647 9.3285 13.9535L14.1593 9.12499H1.125C0.826631 9.12499 0.540484 9.00646 0.329505 8.79548C0.118527 8.58451 0 8.29836 0 7.99999Z\"><\/path><\/svg><\/span><\/span><\/div><span class=\"button__text\">View offer<\/span><\/div><\/div><\/div><\/div><\/div><\/div>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-4fde327 elementor-widget elementor-widget-text-editor\" data-id=\"4fde327\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t\t\t\t\t\t<p><span style=\"font-weight: 400;\">Key takeaways:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Fat degradation during frying<\/b><span style=\"font-weight: 400;\"> proceeds along several routes at once \u2013 through oxidation, hydrolysis and polymerisation. Understanding these mechanisms allows frying fat to be selected deliberately for specific process conditions.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>The durability of <a href=\"https:\/\/rafsol.eu\/en\/offer\/frying-fats\/\">frying fat<\/a><\/b><span style=\"font-weight: 400;\"> depends not only on the composition of the raw material but also on temperature, the presence of water, the type of product being fried and the quality of oil management in the equipment.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">The key parameters for assessing stability are the total polar materials (TPM) figure, the acid value (FFA) and the fatty acid profile \u2013 in particular the content of polyunsaturated fatty acids.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>How often to change frying fat<\/b><span style=\"font-weight: 400;\"> \u2013 there is no single rule, but there are measurable thresholds: European standards indicate 25% TPM as the point at which fat is disqualified. Regular measurement takes the guesswork out of the decision.<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Extending frying fat life is a genuine cost optimisation measure \u2013 appropriate fat selection and operational discipline can reduce feedstock consumption by as much as 30\u201340% (indicative figure).<\/span><\/li>\n<\/ul>\n<p><\/p>\n<h2>What is the oxidative stability of frying fat and why does it matter in production?<\/h2>\n<p><span style=\"font-weight: 400;\">The oxidative stability of frying fat is the ability of the fat to resist oxidation at elevated temperature in the presence of oxygen. The higher the stability, the more slowly degradation processes advance, the longer the fat retains its technological and sensory parameters \u2013 and the lower the unit cost of frying.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">This parameter is directly linked to fatty acid composition. <\/span><b>Fats rich in saturated fatty acids<\/b><span style=\"font-weight: 400;\"> (palmitic, stearic) or in monounsaturated fatty acids (oleic) exhibit considerably higher stability than those with a high proportion of polyunsaturated fatty acids such as linoleic (C18:2) or linolenic (C18:3). This is why <a href=\"https:\/\/rafsol.eu\/en\/offer\/frying-fats\/\"><strong>industrial frying fats<\/strong><\/a> are formulated to minimise PUFA content rather than maximise nutritional value.\u00a0<\/span><\/p>\n<h3>The Rancimat test \u2013 how oxidative stability is measured<\/h3>\n<p><span style=\"font-weight: 400;\">The standard laboratory tool for assessing oxidative stability is the Rancimat test (EN ISO 6886). The result \u2013 expressed as an induction time in hours \u2013 makes it possible to compare frying fats with one another under controlled conditions. For fats intended for intensive industrial frying, the desirable values are usually above 20\u201330 hours, although some specialised frying fats achieve considerably more.<\/span><\/p>\n<p><img decoding=\"async\" class=\"aligncenter wp-image-7422 size-full\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/12\/Projektowanie-tluszczow-na-zamowienie.jpg\" alt=\"The Rancimat test \u2013 how oxidative stability is measured\" width=\"1024\" height=\"680\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/12\/Projektowanie-tluszczow-na-zamowienie.jpg 1024w, https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/12\/Projektowanie-tluszczow-na-zamowienie-300x199.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2025\/12\/Projektowanie-tluszczow-na-zamowienie-768x510.jpg 768w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/p>\n<h2>Fat degradation during frying \u2013 three parallel processes<\/h2>\n<p><b>Fat degradation during frying<\/b><span style=\"font-weight: 400;\"> is not a single process \u2013 it consists of overlapping chemical reactions whose rate depends on process conditions. Understanding each of them is a prerequisite for effective management of frying fat quality.<\/span><\/p>\n<h3>Thermal oxidation<\/h3>\n<p><span style=\"font-weight: 400;\">Oxidation takes place where the fat comes into contact with atmospheric oxygen and is accelerated by high temperature. It produces primarily hydroperoxides, which then undergo further transformation into aldehydes, ketones and carboxylic acids. These compounds are responsible for the deterioration of the sensory characteristics of the fat \u2013 including the appearance of undesirable odours and flavours \u2013 and, as degradation advances, may lead to the formation of products with a potentially adverse effect on health. The more unsaturated double bonds there are in the triacylglycerol molecule, the faster oxidation proceeds.<\/span><\/p>\n<h3>Hydrolysis<\/h3>\n<p><span style=\"font-weight: 400;\">Moisture released from the product being fried reacts with the fat, breaking down ester bonds and releasing free fatty acids (FFA). A rise in FFA lowers the smoke point of the frying fat and accelerates its further degradation. <\/span><b>High-moisture foods<\/b><span style=\"font-weight: 400;\"> \u2013 for example frozen chips or breaded fish \u2013 is one of the main factors accelerating fat consumption.<\/span><\/p>\n<h3>Polymerisation<\/h3>\n<p><span style=\"font-weight: 400;\">At high temperatures, fat molecules combine to form dimers and polymers of high molecular weight. It is precisely these compounds that are responsible for the characteristic darkening of frying fat, the increase in viscosity and the foaming of the oil. They are among the most visible organoleptic indicators of fat exhaustion and can be assessed without measuring equipment. At an advanced stage of degradation, polymerisation leads to the formation of deposits and lacquering, which further reduce heat transfer efficiency and impair the stability of the frying process.<\/span><\/p>\n<table>\n<thead>\n<tr>\n<th><b>Process<\/b><\/th>\n<th><b>Main cause<\/b><\/th>\n<th><b>Analytical indicator<\/b><\/th>\n<th><b>Operational consequence<\/b><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><span style=\"font-weight: 400;\">Oxidation<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Oxygen + high temperature<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Peroxide value, p-AV<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Deterioration of taste and odour, formation of potentially harmful substances<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Hydrolysis<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Water from the product<\/span><\/td>\n<td><span style=\"font-weight: 400;\">FFA<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Lower smoke point, accelerated degradation<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Polymerisation<\/span><\/td>\n<td><span style=\"font-weight: 400;\">High temperature and time<\/span><\/td>\n<td><span style=\"font-weight: 400;\">TPM, viscosity<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Foaming, darkening, increased viscosity, formation of deposits<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<h2>The durability of frying fat \u2013 what actually shortens frying fat life<\/h2>\n<p><b>The durability of frying fat<\/b><span style=\"font-weight: 400;\"> is the net result of feedstock-related and process-related factors. Even the highest-quality frying fats will degrade rapidly under incorrect operating conditions.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Factors that shorten frying fat life:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Excessive temperature<\/b><span style=\"font-weight: 400;\"> \u2013 every 10\u00b0C above the recommended range can significantly increase the rate of oxidation; frying at 185\u2013190\u00b0C instead of 170\u2013175\u00b0C drastically shortens the service life of the fat<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Running the fryer idle<\/b><span style=\"font-weight: 400;\"> \u2013 heated fat with no product in it oxidises more intensively; equipment should be switched off or run at a lower temperature during breaks<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Product residues and crumbs<\/b><span style=\"font-weight: 400;\"> \u2013 these catalyse oxidation and polymerisation reactions, so regular filtration is essential<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Contact with metals<\/b><span style=\"font-weight: 400;\"> \u2013 copper and iron act as pro-oxidants; the material the equipment is made of matters<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Overloading with product at once<\/b><span style=\"font-weight: 400;\"> \u2013 the sudden release of water causes a local increase in free fatty acids (FFA)<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>Unsuitable frying fat composition<\/b><span style=\"font-weight: 400;\"> \u2013 a high PUFA content and the absence of natural or added antioxidants<\/span><\/li>\n<\/ul>\n<h2>How often to change frying fat \u2013 thresholds and control methods<\/h2>\n<p><b>How often to change frying fat<\/b><span style=\"font-weight: 400;\"> is a question that, in a professional production environment, should not be answered intuitively \u2013 it should be based on measurement. Changing too early generates unnecessary costs; changing too late creates quality and legal risk.<\/span><\/p>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-10603 size-full\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-1.jpg\" alt=\"How often to change frying fat \u2013 thresholds and control methods\" width=\"1000\" height=\"600\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-1.jpg 1000w, https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-1-300x180.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-1-768x461.jpg 768w\" sizes=\"(max-width: 1000px) 100vw, 1000px\" \/><\/p>\n<h3>Standards and disqualifying indicators<\/h3>\n<p><span style=\"font-weight: 400;\">European legislation (including Codex Alimentarius guidelines and national sanitary regulations) indicates a level of <\/span><b>25% TPM (Total Polar Materials)<\/b><span style=\"font-weight: 400;\"> as the threshold above which the fat should be replaced. In Germany this limit is enforced through inspections; in Poland it is commonly used as a reference in HACCP systems.<\/span><\/p>\n<p><span style=\"font-weight: 400;\">Supporting indicators:<\/span><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>FFA above 1.0\u20132.5%<\/b><span style=\"font-weight: 400;\"> (depending on the type of fat and the requirements of the plant)<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><b>An acid value above 2\u20135 mg KOH\/g<\/b><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Visible foaming, dark colour and an intense unpleasant odour \u2013 visual and sensory signals as a supplement to measurement<\/span><\/li>\n<\/ul>\n<h3>Field tests \u2013 rapid checks without a laboratory<\/h3>\n<p><span style=\"font-weight: 400;\">Test strips and digital TPM meters (such as the testo 270 or Fri-Check) are available on the market and make it possible to check the condition of the fat directly at the fryer within seconds. In plants with a high turnover of fried products, measurement is recommended at least twice a day, at the beginning and towards the end of the production shift.<\/span><\/p>\n<h2>Extending frying fat life \u2013 practical operational measures<\/h2>\n<p><b>Extending frying fat life<\/b><span style=\"font-weight: 400;\"> is achievable without changing supplier or rebuilding the production line \u2013 consistent operational discipline and the right choice of feedstock are enough.<\/span><\/p>\n<p><b>Measures relating to equipment management:<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Filter the fat at least once a day (or after every shift in intensive production) \u2013 removing solid particles reduces the rate of polymerisation<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Keep the frying temperature within the range recommended by the frying fat manufacturer \u2013 no higher than necessary<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Switch off the fryer or reduce its temperature during breaks longer than 20\u201330 minutes<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Top up with fresh fat as levels fall rather than carrying out infrequent full changes \u2013 continuous replenishment keeps the average age of the fat low<\/span><\/li>\n<\/ul>\n<p><b>Measures relating to feedstock selection:<\/b><\/p>\n<ul>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Choose a frying fat with a high proportion of monounsaturated fatty acids (oleic, C18:1) \u2013 for example frying fats based on high-oleic (HO) sunflower oil or palm olein<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Frying fats with natural antioxidants (tocopherols) or synthetic ones (TBHQ, BHA \u2013 at legally permitted concentrations) \u2013 these slow oxidation down<\/span><\/li>\n<li style=\"font-weight: 400;\" aria-level=\"1\"><span style=\"font-weight: 400;\">Match the frying fat to the specific application: a wet breaded product requires a different specification from dry snack products<\/span><\/li>\n<\/ul>\n<p style=\"text-align: center;\"><strong>\u2014<\/strong><\/p>\n<p style=\"text-align: center;\"><span style=\"font-size: 22px;\"><em>Also read:<a href=\"https:\/\/rafsol.eu\/en\/frying-fat-how-to-select-the-right-frying-medium-and-where-to-buy-foodservice-frying-fats\/\"><strong> Frying fat \u2013 how to select the right frying medium and where to buy foodservice frying fats<\/strong><\/a><i><span>\u00a0<\/span>and<a href=\"https:\/\/rafsol.eu\/en\/from-seed-to-bottle-how-the-vegetable-oil-that-reaches-your-table-is-made\/\"><strong> How the Vegetable Oil Is Made<\/strong><\/a><\/i><\/em><\/span><\/p>\n<p><\/p>\n<p style=\"text-align: center;\"><strong>\u2014<\/strong><\/p>\n<h2>Frying fat composition and stability \u2013 what to check when selecting a supplier<\/h2>\n<p><span style=\"font-weight: 400;\">The oxidative stability of frying fat should be verifiable through documentation, not merely declared verbally. When comparing supplier offers, it is worth requiring the following data:<\/span><\/p>\n<table>\n<thead>\n<tr>\n<th><b>Parameter<\/b><\/th>\n<th><b>What to check<\/b><\/th>\n<th><b>Benchmark for industrial frying fat<\/b><\/th>\n<\/tr>\n<\/thead>\n<tbody>\n<tr>\n<td><span style=\"font-weight: 400;\">Fatty acid profile<\/span><\/td>\n<td><span style=\"font-weight: 400;\">C18:2 (linoleic) content<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Below 15\u201320% for a stable frying fat<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">FFA (free fatty acids)<\/span><\/td>\n<td><span style=\"font-weight: 400;\">% as oleic acid in the fresh product<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Below 0.1% for refined oil<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Smoke point<\/span><\/td>\n<td><span style=\"font-weight: 400;\">\u00b0C<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Min. 210\u2013220\u00b0C<\/span><\/td>\n<\/tr>\n<tr>\n<td><span style=\"font-weight: 400;\">Antioxidant content<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Type and concentration<\/span><\/td>\n<td><span style=\"font-weight: 400;\">Compliance with EU Regulation 1333\/2008<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n<p><img loading=\"lazy\" decoding=\"async\" class=\"aligncenter wp-image-10607 size-full\" src=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-3.jpg\" alt=\"Frying fat composition and stability \u2013 what to check when selecting a supplier\" width=\"1000\" height=\"600\" srcset=\"https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-3.jpg 1000w, https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-3-300x180.jpg 300w, https:\/\/rafsol.eu\/wp-content\/uploads\/2026\/07\/stabilnosc-oksydacyjna-frutyry-3-768x461.jpg 768w\" sizes=\"(max-width: 1000px) 100vw, 1000px\" \/><\/p>\n<h2>FAQ \u2013 oxidative stability of frying fat<\/h2>\n<p><\/p>\n<h3>What is the difference between frying fat and frying oil in terms of oxidative stability?<\/h3>\n<p><span style=\"font-weight: 400;\">Industrial frying fats are deliberately formulated for high oxidative stability \u2013 often through fractionation, enzymatic or chemical interesterification and the selection of feedstocks with a low PUFA content. Standard vegetable oils (such as classic refined sunflower oil) have a higher proportion of polyunsaturated fatty acids and degrade more quickly at frying temperature. In professional catering and production applications the difference in operating costs can be significant.<\/span><\/p>\n<h3>Do hydrogenated frying fats have higher stability than non-hydrogenated ones?<\/h3>\n<p><span style=\"font-weight: 400;\">Historically, yes \u2013 partial or full hydrogenation increases oxidative stability by reducing double bonds. However, traditional partial hydrogenation generates trans isomers, which are limited or eliminated in modern frying fats. An alternative is frying fats based on interesterification and fractionation, which combine high stability with a trans-free profile.<\/span><\/p>\n<h3>What does TPM mean and how is it measured in practice in a production plant?<\/h3>\n<p><span style=\"font-weight: 400;\">TPM (Total Polar Materials) is the combined content of polar compounds formed as a result of fat degradation \u2013 hydrolysis, oxidation and polymerisation. The 25% TPM threshold is the European standard for disqualifying frying fat. In practice it is measured with a digital meter (such as the testo 270) directly in the fryer \u2013 the measurement takes a few seconds and requires no laboratory.<\/span><\/p>\n<h3>Does the type of product being fried affect the rate of frying fat degradation?<\/h3>\n<p><span style=\"font-weight: 400;\">Very much so. Products with a high moisture content (frozen chips, fish, vegetables) hydrolyse the fat intensively and shorten its life. Dry products (crisps, snacks) are far gentler on the frying fat. The choice of frying fat should take account of the specific range of products being fried \u2013 frying fats for wet applications usually have a different composition and a higher smoke point.<\/span><\/p>\n<h3>Does topping up with fresh fat really extend frying fat life?<\/h3>\n<p><span style=\"font-weight: 400;\">Yes \u2013 systematically topping up losses with fresh fat (the continuous replenishment method) maintains a lower average TPM level than a strategy of infrequent full changes. In large production plants and high-turnover frying operations this is a standard optimisation practice.<\/span><\/p>\n<blockquote><p><span style=\"font-weight: 400;\">Selecting the right frying fat for a specific frying process \u2013 taking into account composition, oxidative stability and operating conditions \u2013 is a decision with a real impact on production costs and on the quality of the final product. If your plant is struggling with rapid fat degradation, foaming of the frying fat or difficulties in maintaining consistent quality in the fried product, <a href=\"https:\/\/rafsol.eu\/en\/quote-request\/\"><strong>please get in touch<\/strong><\/a>.<\/span><\/p>\n<p><b>Our technologists will analyse your application and propose a frying fat matched to your process, certification and cost requirements.<\/b><\/p><\/blockquote>\n\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t","protected":false},"excerpt":{"rendered":"<p>The oxidative stability of frying fat determines how many frying cycles the fat will withstand before it loses its technological properties and becomes a source of quality problems. In professional frying operations, catering establishments and production lines, this is one of the key parameters directly affecting operating costs and the safety of the final product. [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":10610,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[104],"tags":[],"class_list":["post-10801","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-knowledge-base-rafsol"],"_links":{"self":[{"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/posts\/10801","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/comments?post=10801"}],"version-history":[{"count":1,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/posts\/10801\/revisions"}],"predecessor-version":[{"id":10802,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/posts\/10801\/revisions\/10802"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/media\/10610"}],"wp:attachment":[{"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/media?parent=10801"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/categories?post=10801"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/rafsol.eu\/en\/wp-json\/wp\/v2\/tags?post=10801"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}