--- title: Milk, cheese and yoghurt — a lesson of Mova's school · trees and pragmatics description: «Milk, cheese and yoghurt», a lesson of the chemistry course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: Leave a glass of milk on a sunny windowsill and by evening it smells sour and has lumps in it. --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Chemistry](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/) / Milk, cheese and yoghurt # Milk, cheese and yoghurt Lesson 22 of the chemistry course of Mova's primary school: 17 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/chemistry/22-milk-cheese-and-yoghurt/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/0/) — Leave a glass of milk on a sunny windowsill and by evening it smells sour and has lumps in it. - [1](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/1/) — Bacteria have eaten the milk sugar and made acid, and the acid made the milk proteins clump. - [2](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/2/) — People learned to use this on purpose. - [3](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/3/) — Friendly bacteria turn milk into tangy yoghurt; bacteria and a substance called rennet split milk into solid curds and watery whey, and the curds become cheese, the curds and whey of Little Miss Muffet. - [4](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/4/) — Milk is also full of tiny fat droplets. - [5](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/5/) — Shake cream in a jar long enough and the droplets stick together into butter, leaving buttermilk behind; whisk it gently instead and the fat holds air bubbles as whipped cream. - [6](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/6/) — Heat milk and a skin forms on top, which traps steam until the milk suddenly rushes over the edge of the pan. - [7](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/7/) — And ice cream feels smooth because it is stirred while freezing, keeping its ice crystals tiny. - [8](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/8/) — Milk goes sour when bacteria eat the milk sugar and make acid, which makes the proteins clump; cold slows the bacteria, so milk keeps longer in the fridge. - [9](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/9/) — Cheese-makers add bacteria and rennet to milk, which separates into solid curds and watery whey; the curds become cheese. - [10](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/10/) — The blue-green veins in blue cheese are a safe mould added on purpose; other moulds on food can be harmful. - [12](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/12/) — A skin forms on hot milk as proteins and fat at the surface dry a little and join; stirring or covering the pan stops it. - [14](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/14/) — Live yoghurt contains living bacteria that are harmless or helpful; a spoonful in warm milk can make more yoghurt. - [15](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/15/) — Lactose intolerance means the body cannot digest milk sugar well, because some people stop making the enzyme that breaks it down (an enzyme is a helper substance the body makes to break food apart). - [16](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/16/) — Lactose-free milk has the enzyme added, which breaks the milk sugar into simpler sugars that taste sweeter. - [17](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/17/) — Whisking cream traps air bubbles, held by fat droplets; whisking too long turns it lumpy and then into butter. - [18](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/22-milk-cheese-and-yoghurt/18/) — Ice cream is stirred while freezing so the ice crystals stay tiny; melted and refrozen ice cream grows big crystals and feels crunchy. - ← previous: [Bread rising: yeast at work](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/21-bread-rising-yeast-at-work/) - next →: [Browning apples, rotting and mould](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/23-browning-apples-rotting-and-mould/) - ↑ back to [Chemistry](https://md.mova.elamur.ai/free/en/corpora/school/chemistry/)