{"id":5443,"date":"2025-05-30T16:02:20","date_gmt":"2025-05-30T16:02:20","guid":{"rendered":"https:\/\/blog.mealnstock.com\/milk-and-color-experiment-the-magic-of-an-invisible-emulsion\/"},"modified":"2025-10-15T01:48:59","modified_gmt":"2025-10-15T01:48:59","slug":"magic-milk-experiment","status":"publish","type":"post","link":"https:\/\/blog.mealnstock.com\/en\/magic-milk-experiment\/","title":{"rendered":"Milk and color experiment: the magic of an invisible emulsion"},"content":{"rendered":"\t\t<div data-elementor-type=\"wp-post\" data-elementor-id=\"5443\" class=\"elementor elementor-5443 elementor-5382\" data-elementor-post-type=\"post\">\n\t\t\t\t<div class=\"elementor-element elementor-element-b94bcff e-con-full e-flex e-con e-parent\" data-id=\"b94bcff\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t<div class=\"elementor-element elementor-element-1907228 e-con-full e-flex e-con e-child\" data-id=\"1907228\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t<div class=\"elementor-element elementor-element-603afc7 e-con-full e-flex e-con e-child\" data-id=\"603afc7\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t<div class=\"elementor-element elementor-element-9d49796 elementor-widget elementor-widget-heading\" data-id=\"9d49796\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"heading.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t<h1 class=\"elementor-heading-title elementor-size-default\">Milk and color experiment: the magic of an invisible emulsion<\/h1>\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-5a1a559 e-con-full e-flex e-con e-child\" data-id=\"5a1a559\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t<div class=\"elementor-element elementor-element-824ccfb elementor-hidden-desktop elementor-hidden-tablet elementor-hidden-mobile elementor-widget elementor-widget-text-editor\" data-id=\"824ccfb\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-start=\"130\" data-end=\"205\">Discover why milk is a natural emulsion with this magical experiment. Fun activity to observe how soap breaks down fat.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-55172a5 elementor-align-center elementor-widget elementor-widget-post-info\" data-id=\"55172a5\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"post-info.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<ul class=\"elementor-inline-items elementor-icon-list-items elementor-post-info\">\n\t\t\t\t\t\t\t\t<li class=\"elementor-icon-list-item elementor-repeater-item-4db0cb4 elementor-inline-item\" itemprop=\"datePublished\">\n\t\t\t\t\t\t<a href=\"https:\/\/blog.mealnstock.com\/en\/2025\/05\/30\/\">\n\t\t\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-icon\">\n\t\t\t\t\t\t\t\t<svg aria-hidden=\"true\" class=\"e-font-icon-svg e-fas-calendar\" viewBox=\"0 0 448 512\" xmlns=\"http:\/\/www.w3.org\/2000\/svg\"><path d=\"M12 192h424c6.6 0 12 5.4 12 12v260c0 26.5-21.5 48-48 48H48c-26.5 0-48-21.5-48-48V204c0-6.6 5.4-12 12-12zm436-44v-36c0-26.5-21.5-48-48-48h-48V12c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v52H160V12c0-6.6-5.4-12-12-12h-40c-6.6 0-12 5.4-12 12v52H48C21.5 64 0 85.5 0 112v36c0 6.6 5.4 12 12 12h424c6.6 0 12-5.4 12-12z\"><\/path><\/svg>\t\t\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<span class=\"elementor-icon-list-text elementor-post-info__item elementor-post-info__item--type-date\">\n\t\t\t\t\t\t\t\t\t\t<time>May 30, 2025<\/time>\t\t\t\t\t<\/span>\n\t\t\t\t\t\t\t\t\t<\/a>\n\t\t\t\t<\/li>\n\t\t\t\t<\/ul>\n\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-27326ac elementor-widget elementor-widget-text-editor\" data-id=\"27326ac\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<p data-start=\"230\" data-end=\"607\"><img fetchpriority=\"high\" decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5390 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-17.jpg?resize=800%2C601&#038;ssl=1\" alt=\"magic milk experiment\" width=\"800\" height=\"601\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-17.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-17.jpg?resize=300%2C225&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-17.jpg?resize=768%2C577&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-17.jpg?resize=750%2C563&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-17.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/p><p>In this post, we are going to explore one of the lesser-known and perhaps most surprising properties of<strong> milk<\/strong>, the fact that it is a <strong>natural emulsion<\/strong>. With the help of food colouring and some liquid soap, we are not only going to observe what happens when the soap comes into contact with the milk and the colours disperse all at once, but we will also discover how this so-called <strong>magic milk experiment <\/strong>works.<\/p><p>It is an ideal activity to awaken the scientific curiosity of children (and why not, also adults). That white liquid you may have in your refrigerator, whether it is whole, skimmed or lactose-free, hides a complex structure that is worth knowing.<\/p><figure id=\"attachment_5411\" aria-describedby=\"caption-attachment-5411\" style=\"width: 533px\" class=\"wp-caption aligncenter\"><img decoding=\"async\" data-recalc-dims=\"1\" class=\"wp-image-5411 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-33.jpg?resize=533%2C800&#038;ssl=1\" alt=\"Milk is an emulsion\" width=\"533\" height=\"800\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-33.jpg?w=533&amp;ssl=1 533w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-33.jpg?resize=200%2C300&amp;ssl=1 200w\" sizes=\"(max-width: 533px) 100vw, 533px\" \/><figcaption id=\"caption-attachment-5411\" class=\"wp-caption-text\">Photo by Kim Leary on Unsplash<\/figcaption><\/figure><p>No matter where in the world we live, <strong>milk is our first food,<\/strong> and our bodies are designed to feed on breast milk from birth. It is not surprising, then, that at some point in history, we began consuming the <strong>milk of other mammals<\/strong>. From the <a href=\"https:\/\/www.researchgate.net\/publication\/363118819_Author_Correction_Dairying_diseases_and_the_evolution_of_lactase_persistence_in_Europe\" target=\"_blank\" rel=\"noopener\">analysis of organic residues on prehistoric ceramics<\/a> at several archaeological sites in Europe and Southwest Asia, we know that their consumption began <strong>about 9000 years ago.<\/strong><\/p><p>Over time, some humans developed the ability to process lactose beyond infancy, an ability that most people lose as they grow older. It is currently estimated that approximately <strong><a href=\"https:\/\/www.mdpi.com\/2673-4060\/6\/1\/27\" target=\"_blank\" rel=\"noopener\">30% of the global population<\/a> tolerates lactose in adulthood<\/strong>, especially in countries in Northern Europe and some traditional cattle-raising communities in Africa and Asia. In addition,<strong> milk from other mammals is not the same as human milk<\/strong>: its protein, fat and sugar content, for example, is different.<\/p><p>Milk may seem like a simple liquid, and although we know that it has a sweet, neutral taste and a characteristic whitish colour, it is not just colored water. In fact, it has no molecule or pigment that directly produces that colour; instead, <strong>its appearance is the result of the dispersion of fat and protein particles in suspension<\/strong> (we\u2019ll talk more about this in another post). In reality, <strong>milk is an<\/strong> <strong>emulsion<\/strong>, like mayonnaise, and if you want to know more about what an emulsion is, you can read this other experiment:<br \/>\ud83d\udc49 <a href=\"https:\/\/blog.mealnstock.com\/en\/homemade-mayo-vs-store-bought-comparison\/\" target=\"_blank\" rel=\"noopener\">https:\/\/blog.mealnstock.com\/mayonesa-casera-vs-comprada-comparacion<\/a><\/p><div class=\"elementor-element elementor-element-47df228 e-con-full e-flex e-con e-parent e-lazyloaded\" data-id=\"47df228\" data-element_type=\"container\"><div class=\"elementor-element elementor-element-aa9f35e elementor-widget__width-initial elementor-widget elementor-widget-text-editor\" data-id=\"aa9f35e\" data-element_type=\"widget\" data-widget_type=\"text-editor.default\"><div class=\"elementor-widget-container\"><h2><strong>So, milk is an emulsion?<\/strong><\/h2><p>Yes, <strong>milk has a high water content<\/strong> (almost 90%), but it also contains fats or lipids (what is the difference? Good question for another post). As we know, water and lipids do not mix, and fat floats because it has a lower density than water. However, in the case of milk, we don&#8217;t see a visible separation between the water and the fat it contains; instead, it looks like a homogeneous substance. This is <strong>because milk is a natural emulsion<\/strong> of the <strong>\u201coil-in-water\u201d <\/strong>type &#8211; that is, small <strong>droplets of fat suspended in water<\/strong> &#8211; and because of this, the mixture looks fluid and stable.<\/p><p>Besides water and fat (mostly triglycerides), milk contains other ingredients such as lactose, which is a type of sugar, as well as proteins, minerals and vitamins. What allows milk to appear uniform and stable is a tiny structure of <strong>nanometric<\/strong> size, that is, much smaller than anything we can see under a microscope. To give you an idea, a nanometer is almost <strong>a hundred thousand times smaller than the thickness of a human hair<\/strong> or about <strong>a thousand times thinner than a bacterium<\/strong>. This structure is called <a href=\"https:\/\/pmc.ncbi.nlm.nih.gov\/articles\/PMC6836175\/\" target=\"_blank\" rel=\"nofollow noopener\"><strong>MFGM<\/strong><\/a> ( <em>Milk Fat Globule Membrane).<\/em><\/p><p>The MFGM membrane acts like small fluffs stuck to the fat particles, preventing them from binding to each other and floating to the surface. This membrane is made up of special compounds called <strong>phospholipids<\/strong>, <strong>sphingolipids<\/strong> and <strong>glycoproteins<\/strong>, which act as a natural barrier between water and fat.<\/p><p>It has also been observed that some milk proteins, such as <strong>caseins<\/strong>, contribute to the stability of the emulsion, even though they are not a direct part of the membrane. Thanks to this invisible organization, milk not only looks white and fluid, but also plays important roles in fat digestion and infant nutrition, especially in the early stages of life.<\/p><p><img decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5417 size-large\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=1024%2C576&#038;ssl=1\" alt=\"milk is an emulsion\" width=\"1024\" height=\"576\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?w=1920&amp;ssl=1 1920w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=300%2C169&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=1024%2C576&amp;ssl=1 1024w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=768%2C432&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=1536%2C864&amp;ssl=1 1536w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=750%2C422&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=1500%2C844&amp;ssl=1 1500w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_membrana.png?resize=480%2C270&amp;ssl=1 480w\" sizes=\"(max-width: 1024px) 100vw, 1024px\" \/><\/p><h2><strong>What happens to milk when we apply heat?<\/strong><\/h2><p>Thanks to <strong>the interaction between fat globules and milk proteins<\/strong> (casein and whey), <strong>milk has a high heat tolerance<\/strong>. This means that, if we heat the milk slowly to reduce it, the emulsion does not break. The MFGM membrane remains stable, while the whey proteins react to heat and change the milk&#8217;s texture. As <strong>the temperature rises<\/strong>, <strong>these proteins begin to clump together and thicken the mixture.<\/strong> The result is a creamier milk, slightly more yellow in colour, but still a stable emulsion. This is the basis for products such as <strong>evaporated milk.<\/strong><\/p><p>We have already seen that milk is an emulsion, thanks to the <strong>MFGM<\/strong> membrane, and that this membrane remains intact even when we heat the milk. But what happens if something external attacks this membrane?<\/p><p><strong>Here is a step-by-step activity for you to try at home.<\/strong><\/p><\/div><\/div><\/div>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-f619ee8 elementor-widget elementor-widget-text-editor\" data-id=\"f619ee8\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<h2><strong>Activity: Breaking the emulsion, the real magic milk experiment<\/strong><\/h2><p>This fun and visual experiment allows us to <strong>easily see something that is not normally seen with the naked eye<\/strong>: the invisible structure of milk. Here is the step-by-step activity for you to try at home, and the explanation of the magic milk experiment.<\/p><h3><strong>Materials:<\/strong><\/h3><ul><li>3-4 tablespoons (45-60 ml) <strong>whole cow&#8217;s milk<\/strong><\/li><li>4-5 drops of <strong>food colouring<\/strong> (you can use several colours)<\/li><li>1 tablespoon <strong>liquid soap<\/strong> (can be dishwashing or hand soap)<\/li><li>1 flat-bottomed <strong>plate <\/strong><\/li><li>2-3 <strong>cotton swabs<\/strong> (Q-tips)<\/li><\/ul><p><img loading=\"lazy\" decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5396 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-23.jpg?resize=800%2C602&#038;ssl=1\" alt=\"Ingredients for magic milk experiment\" width=\"800\" height=\"602\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-23.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-23.jpg?resize=300%2C226&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-23.jpg?resize=768%2C578&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-23.jpg?resize=750%2C564&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-23.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/p><h3><strong>Procedure:<\/strong><\/h3><h4><strong>Step 1. Pour the milk<\/strong><strong>\u00a0into the plate<\/strong><\/h4><p>You only need to cover the bottom with a thin layer of milk.<\/p><p><img loading=\"lazy\" decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5399 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-26.jpg?resize=800%2C602&#038;ssl=1\" alt=\"\" width=\"800\" height=\"602\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-26.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-26.jpg?resize=300%2C226&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-26.jpg?resize=768%2C578&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-26.jpg?resize=750%2C564&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-26.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/p><h4><strong>Step 2. Add the food coloring<\/strong><\/h4><p>Place three or four drops of each color near the center of the plate.<img loading=\"lazy\" decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5402 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-28.jpg?resize=800%2C602&#038;ssl=1\" alt=\"\" width=\"800\" height=\"602\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-28.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-28.jpg?resize=300%2C226&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-28.jpg?resize=768%2C578&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-28.jpg?resize=750%2C564&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-28.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/p><h4><strong>Step 3. Dip the swab in soap<\/strong><\/h4><p>All you need is a swab tip lightly moistened with liquid soap.<\/p><p><img loading=\"lazy\" decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5414 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-40.jpg?resize=800%2C464&#038;ssl=1\" alt=\"\" width=\"800\" height=\"464\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-40.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-40.jpg?resize=300%2C174&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-40.jpg?resize=768%2C445&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-40.jpg?resize=750%2C435&amp;ssl=1 750w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/><\/p><h4><strong>Step 4. Touch the milk with the swab <\/strong><\/h4><p>Place the tip of the soapy swab in the center of the dish, where the colour drops are. Do not remove it until it stops flowing. Observe the reaction! You can test in different spots or with new swabs moistened with soap.<\/p><p><strong><img loading=\"lazy\" decoding=\"async\" data-recalc-dims=\"1\" class=\"aligncenter wp-image-5393 size-full\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-02.jpg?resize=800%2C601&#038;ssl=1\" alt=\"explanation of the magic milk experiment\" width=\"800\" height=\"601\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-02.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-02.jpg?resize=300%2C225&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-02.jpg?resize=768%2C577&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-02.jpg?resize=750%2C563&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-02.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 800px) 100vw, 800px\" \/> <\/strong><\/p><h3><strong>Questions for discussion<\/strong><\/h3><ul><li>What happened when we touched the swab?<\/li><li>Why did the colours start to move just at that moment?<\/li><li>What happens if we do not add colourant? Does it make any difference?<\/li><li>Do you think the effect would be the same with vegetable milk or skim milk?<\/li><li>What happens if instead of cow&#8217;s milk we use vegetable or skim milk?<\/li><\/ul>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<div class=\"elementor-element elementor-element-71a6346 elementor-widget elementor-widget-video\" data-id=\"71a6346\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;youtube_url&quot;:&quot;https:\\\/\\\/www.youtube.com\\\/shorts\\\/q-9xoNT02wc&quot;,&quot;mute&quot;:&quot;yes&quot;,&quot;video_type&quot;:&quot;youtube&quot;,&quot;controls&quot;:&quot;yes&quot;}\" data-widget_type=\"video.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-wrapper elementor-open-inline\">\n\t\t\t<div class=\"elementor-video\"><\/div>\t\t<\/div>\n\t\t\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-bc7bef1 elementor-widget elementor-widget-text-editor\" data-id=\"bc7bef1\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<hr><p class=\"elementor-heading-title elementor-size-default\"> <\/p>\t\t\t\t\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-c2f30d6 e-con-full e-flex e-con e-child\" data-id=\"c2f30d6\" data-element_type=\"container\" data-e-type=\"container\">\n\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-12e22c6 e-flex e-con-boxed e-con e-parent\" data-id=\"12e22c6\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t<div class=\"elementor-element elementor-element-1076b72 e-con-full e-flex e-con e-child\" data-id=\"1076b72\" data-element_type=\"container\" data-e-type=\"container\">\n\t\t\t\t<div class=\"elementor-element elementor-element-fb9ee0f elementor-widget__width-initial elementor-widget elementor-widget-text-editor\" data-id=\"fb9ee0f\" data-element_type=\"widget\" data-e-type=\"widget\" data-widget_type=\"text-editor.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t\t\t<h3 data-start=\"0\" data-end=\"41\"><strong data-start=\"0\" data-end=\"39\">What do we learn from this experiment?<\/strong><\/h3><p><strong>Soap<\/strong> (or liquid detergent) contains a substance called <strong>surfactant,<\/strong> and it is a very special molecule, one part of the molecule \u201cloves\u201d water (it is hydrophilic), and the other part \u201cloves\u201d fat (it is lipophilic). It is a kind of \u201cinvisible force\u201d that holds the water together and also holds the fat droplets in the milk together.<\/p><p data-pm-slice=\"1 1 []\"><strong>Two phenomena<\/strong> occur at the same time when <strong>we add soap to milk<\/strong>: on one hand, <strong>the soap breaks the surface tension of the liquid<\/strong>, causing an <strong>immediate movement on the surface<\/strong> that pushes the food coloring in different directions; on the other hand,<strong> it interferes with the MFGM membrane<\/strong>, which is responsible for keeping the fat suspended in water and for allowing milk to behave like a stable emulsion. As this membrane weakens and breaks, <strong>the fat droplets are released and begin to spread out<\/strong>, creating the <strong>colourful swirls on the surface<\/strong> of the milk. It\u2019s not magic; what we\u2019re observing is how a natural emulsion transforms when its invisible structure is broken apart.<\/p>\t\t\t\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-ef90404 e-flex e-con-boxed e-con e-parent\" data-id=\"ef90404\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t\t<div class=\"e-con-inner\">\n\t\t\t\t\t<\/div>\n\t\t\t\t<\/div>\n\t\t<div class=\"elementor-element elementor-element-fd75762 e-con-full e-flex e-con e-parent\" data-id=\"fd75762\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t<div class=\"elementor-element elementor-element-637d7df elementor-headline--style-rotate elementor-widget elementor-widget-animated-headline\" data-id=\"637d7df\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;rotating_text&quot;:&quot;Experiments\\nActivities&quot;,&quot;headline_style&quot;:&quot;rotate&quot;,&quot;rotate_iteration_delay&quot;:2491,&quot;animation_type&quot;:&quot;typing&quot;,&quot;loop&quot;:&quot;yes&quot;}\" data-widget_type=\"animated-headline.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<h3 class=\"elementor-headline elementor-headline-animation-type-typing elementor-headline-letters\">\n\t\t\t\t\t<span class=\"elementor-headline-plain-text elementor-headline-text-wrapper\">Explore more<\/span>\n\t\t\t\t<span class=\"elementor-headline-dynamic-wrapper elementor-headline-text-wrapper\">\n\t\t\t\t\t<span class=\"elementor-headline-dynamic-text elementor-headline-text-active\">\n\t\t\t\tExperiments\t\t\t<\/span>\n\t\t\t\t\t<span class=\"elementor-headline-dynamic-text\">\n\t\t\t\tActivities\t\t\t<\/span>\n\t\t\t\t\t\t<\/span>\n\t\t\t\t<\/h3>\n\t\t\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-01ed7c3 e-con-full e-flex e-con e-parent\" data-id=\"01ed7c3\" data-element_type=\"container\" data-e-type=\"container\" data-settings=\"{&quot;background_background&quot;:&quot;classic&quot;}\">\n\t\t\t\t<div class=\"elementor-element elementor-element-cdf71bc elementor-widget__width-initial elementor-grid-tablet-3 elementor-grid-3 elementor-grid-mobile-1 elementor-widget elementor-widget-portfolio\" data-id=\"cdf71bc\" data-element_type=\"widget\" data-e-type=\"widget\" data-settings=\"{&quot;item_ratio&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:1.0500000000000000444089209850062616169452667236328125,&quot;sizes&quot;:[]},&quot;row_gap&quot;:{&quot;unit&quot;:&quot;em&quot;,&quot;size&quot;:1,&quot;sizes&quot;:[]},&quot;columns_tablet&quot;:&quot;3&quot;,&quot;columns&quot;:&quot;3&quot;,&quot;columns_mobile&quot;:&quot;1&quot;,&quot;item_gap&quot;:{&quot;unit&quot;:&quot;px&quot;,&quot;size&quot;:&quot;&quot;,&quot;sizes&quot;:[]}}\" data-widget_type=\"portfolio.default\">\n\t\t\t\t<div class=\"elementor-widget-container\">\n\t\t\t\t\t\t\t<div class=\"elementor-portfolio elementor-grid elementor-posts-container\" role=\"list\">\n\t\t\t\t<article class=\"elementor-portfolio-item elementor-post elementor-filter-873 post-5564 post type-post status-publish format-standard has-post-thumbnail hentry category-experiments\" role=\"listitem\">\n\t\t\t<a class=\"elementor-post__thumbnail__link\" href=\"https:\/\/blog.mealnstock.com\/en\/why-oil-and-water-dont-mix-the-science-of-emulsions-in-cooking\/\">\n\t\t\t\t<div class=\"elementor-portfolio-item__img elementor-post__thumbnail\">\n\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"577\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/01\/exp-08.jpg?fit=768%2C577&amp;ssl=1\" class=\"attachment-medium_large size-medium_large wp-image-5565\" alt=\"\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/01\/exp-08.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/01\/exp-08.jpg?resize=300%2C225&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/01\/exp-08.jpg?resize=768%2C577&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/01\/exp-08.jpg?resize=750%2C563&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/01\/exp-08.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t<\/div>\n\t\t\t\t<div class=\"elementor-portfolio-item__overlay\">\n\t\t\t\t<h2 class=\"elementor-portfolio-item__title\">\n\t\tWhy oil and water don&#8217;t mix: the science of emulsions in cooking\t\t<\/h2>\n\t\t\t\t<\/div>\n\t\t\t\t<\/a>\n\t\t<\/article>\n\t\t\t\t<article class=\"elementor-portfolio-item elementor-post elementor-filter-873 post-3857 post type-post status-publish format-standard has-post-thumbnail hentry category-experiments\" role=\"listitem\">\n\t\t\t<a class=\"elementor-post__thumbnail__link\" href=\"https:\/\/blog.mealnstock.com\/en\/homemade-playdough-texture-experiment\/\">\n\t\t\t\t<div class=\"elementor-portfolio-item__img elementor-post__thumbnail\">\n\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"578\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/02\/crust_pie_post-39.jpg?fit=768%2C578&amp;ssl=1\" class=\"attachment-medium_large size-medium_large wp-image-3846\" alt=\"\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/02\/crust_pie_post-39.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/02\/crust_pie_post-39.jpg?resize=300%2C226&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/02\/crust_pie_post-39.jpg?resize=768%2C578&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/02\/crust_pie_post-39.jpg?resize=750%2C564&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/02\/crust_pie_post-39.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t<\/div>\n\t\t\t\t<div class=\"elementor-portfolio-item__overlay\">\n\t\t\t\t<h2 class=\"elementor-portfolio-item__title\">\n\t\tFrom Flaky Pastry to Homemade Playdough: Experiment with Texture\t\t<\/h2>\n\t\t\t\t<\/div>\n\t\t\t\t<\/a>\n\t\t<\/article>\n\t\t\t\t<article class=\"elementor-portfolio-item elementor-post elementor-filter-873 post-4795 post type-post status-publish format-standard has-post-thumbnail hentry category-experiments\" role=\"listitem\">\n\t\t\t<a class=\"elementor-post__thumbnail__link\" href=\"https:\/\/blog.mealnstock.com\/en\/is-mustard-acidic-purple-cabbage-ph-test\/\">\n\t\t\t\t<div class=\"elementor-portfolio-item__img elementor-post__thumbnail\">\n\t\t\t<img loading=\"lazy\" decoding=\"async\" width=\"768\" height=\"578\" src=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/03\/ph_experiment-25.jpg?fit=768%2C578&amp;ssl=1\" class=\"attachment-medium_large size-medium_large wp-image-4770\" alt=\"\" srcset=\"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/03\/ph_experiment-25.jpg?w=800&amp;ssl=1 800w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/03\/ph_experiment-25.jpg?resize=300%2C226&amp;ssl=1 300w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/03\/ph_experiment-25.jpg?resize=768%2C578&amp;ssl=1 768w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/03\/ph_experiment-25.jpg?resize=750%2C564&amp;ssl=1 750w, https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/03\/ph_experiment-25.jpg?resize=500%2C375&amp;ssl=1 500w\" sizes=\"(max-width: 768px) 100vw, 768px\" \/>\t\t<\/div>\n\t\t\t\t<div class=\"elementor-portfolio-item__overlay\">\n\t\t\t\t<h2 class=\"elementor-portfolio-item__title\">\n\t\tEasy Purple Cabbage pH Experiment: How acidic is mustard?\t\t<\/h2>\n\t\t\t\t<\/div>\n\t\t\t\t<\/a>\n\t\t<\/article>\n\t\t\t\t<\/div>\n\t\t\t\t\t\t<\/div>\n\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>Discover why milk is a natural emulsion with this magical experiment. Fun activity to observe how soap breaks down fat. <\/p>\n","protected":false},"author":1,"featured_media":5409,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"elementor_header_footer","format":"standard","meta":{"nf_dc_page":"","_monsterinsights_skip_tracking":false,"_monsterinsights_sitenote_active":false,"_monsterinsights_sitenote_note":"","_monsterinsights_sitenote_category":0,"_jetpack_memberships_contains_paid_content":false,"footnotes":""},"categories":[],"tags":[],"class_list":["post-5443","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry"],"blocksy_meta":[],"jetpack_featured_media_url":"https:\/\/i0.wp.com\/blog.mealnstock.com\/wp-content\/uploads\/2025\/05\/milk_experiment-19.jpg?fit=800%2C601&ssl=1","jetpack_sharing_enabled":true,"_links":{"self":[{"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/posts\/5443","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/comments?post=5443"}],"version-history":[{"count":3,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/posts\/5443\/revisions"}],"predecessor-version":[{"id":5662,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/posts\/5443\/revisions\/5662"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/media\/5409"}],"wp:attachment":[{"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/media?parent=5443"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/categories?post=5443"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/blog.mealnstock.com\/en\/wp-json\/wp\/v2\/tags?post=5443"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}