Why should milk boil to the rim?
In some cases hot milk is needed.
My example is a ready made mixture for milk rice.
The direction says I should heat the milk until it shows foam raising, which often raises up to the rim (or more).
I would think it is enough to heat to 2 °C below boiling should be ok, for example? Or to when it almost boils, from experience?
Why is this needed?
Just to assure the milk is heated to it's boiling point?
Or maybe to have some specific reactions taking place?
Best Answer
There are some applications where actually boiling the milk is needed, for example when you want to precipitate out some of the proteins - they build that fuzzy film on the bottom and the skin on top during cooling. In other cases, it is about sterilization - for example for yogurt, you keep the milk boiling for longer time, and it is almost impossible to keep it at just under boiling, unless you make a sophisticated thermoregulated setup and take the extra time needed to heat it slowly so you don't overshoot.
You also have to consider whether the temperature is needed by ingredients other than the milk and the starch. For example, if you are making a pudding with both starch and yolks, you have to hold it a couple of minutes at boiling to deactivate the amylase.
For milk rice, you don't strictly need boiling, but you have to get really close. Different starches thicken at different temperatures, but practivally all I have read about are between 94 and 100 Celsius. So if your starch hits the sweet spot at 97.2 C, then just watching it and noticing that it is very close to a boil is not of much help. First, you run the risk of stopping too early, which will ruin the milk rice(as opposed to stopping after it boils, which will result in good milk rice). Second, the last few degrees of milk boiling go so fast, you may not manage to remove it from the heat before boiling anyway.
If you know the exact temperature for the starch you are using, you could in principle get away with making milk rice a couple of degrees lower. It is rather impractical, but possible.
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Why is the boiling point of milk?
The boiling point of cow's milk is around 203\xb0F (95\xb0C) ( 1 ). That means if you're adding milk to a recipe that'll be cooked or baked, such as one for pudding or cake, it will technically reach its boiling point during the cooking process.How do you boil milk properly?
When milk is heated further, the water vapour expands, pressure builds up and lifts the creamy layer up and thus the milk spills out. But in case of water, the water vapour escapes very easily on boiling since it does not have any layer on the surface to interrupt till complete evaporation of the liquid.Why does boiling milk overflow?
On the stove Heat just until bubbles form around the edge and steam begins to rise from the milk. Stirring frequently will prevent a film layer from forming.FOOD FAQ #10 : Kacha doodh? Can you drink milk directly without boiling? Dr.Education.
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