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Question about gravity and sediments

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I'm a retired mining engineer. Heavy media separation is sometimes used to separate minerals by specific gravity. From https://www.911metallurgist.com/blog/dense-heavy-medium-separation-hms-dms: "Since most of the liquids used in the laboratory are expensive or toxic, the dense medium used in industrial separations is a thick suspension, or pulp, of some heavy solid in water, which behaves as a heavy liquid."

For this method to work, the solids must be very fine so that it stays in suspension long enough for the separation to take place. This is the same effect as floating a hydrometer in wort that has very fine yeast suspended - the water with yeast acts as a heavy liquid. I have no idea what the overall specific gravity increase with yeast in water would be - probably extremely small. But the principle is valid.
 
On top of all this what I read as 1.050 might be read as 1.052 using the hygrometer. It is all subjective to the person and their eyes. Maybe we need to add a centrifuge to our list of 'necessary' equipment. One more thing to geek out about.
 
It would be more vital on the FG side, because 0.99 vs .988 etc is more dry by almost 300% less sugar. Yea parallax and margin of eyeball error is huge.
Cool.
Srinath.
 
Well milk has a whole mess of protein and sugars like lactose that will keep fat suspended in the colloid that is milk. However, mechanically separating fat makes it a basic not dissolved, just there along with type of suspension. Yea emulsion - not for fat, but the rest of milk can not be mechanically separated - you need to break it with rennet or lemon or acetic acid etc. or bacteria etc.
So milk is a colloid or emulsion (just a colloid with 2 liquids) but fat is just there in the mix, held in by some minimal cohesion, mechanically disturb it by beating it and gravity takes over and floats up.
Sorry trying to remember 9th grade chemistry/physics here. Not googled up now. So some errors may be present.
Cool.
Srinath.
 
I guess milk is a colloid - From annenbergs chemistry learner - https://www.learner.org/courses/che...s=U&num=Ym5WdElUQS9PU289&sec=YzJWaklUQS9NaW89

A solution is more than just a homogenous mixture. It is a homogenous mixture down to the molecular level. So, even if it looks homogeneous to the human eye, there can still be groups of molecules clumped together that make it not a solution. Homogenized milk isn't a solution. Rather, it is a colloid—a mixture in which very small particles of one substance are distributed evenly throughout another substance. The clumps of fat in the milk, while small, are still in groups of fat molecules. If individual fat molecules were uniformly spread throughout the milk, homogenized milk would be a solution.

I guess by whipping it, we get the fat globules to collide (hey is that why its called a collide ??? LOL.) and they break their protein bonds free and join up with other fat and there on gravity takes up and they float up.

Cool.
Srinath.
 
What about the friction factor on the glass hydrometer submerged in a solution of varying size and density particulate matter that will constantly change with brew process, ingredients, type of minerals in the water, temperate, and gravitational pull based on sample location from the equator?
 
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What about the friction factor on the glass hydrometer submerged in a solution of varying size and density particulate matter that will constantly change with brew process, ingredients, type of minerals in the water, temperate, and gravitational pull based on sample location from the equator?
I can't tell if you're being serious or just taking the piss, I still "liked" your post. Either way.
 
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