Hey everybody, welcome back to Explain Macam 5, a podcast where we take the questions you always wanted to ask and talk about them in a way that's easy to understand. We're your hosts, I'm Tim. Hey everyone, I'm Kevin. So Kevin, today we're talking about a common dining table question, and that is, what made us settle on cow's milk and chicken eggs as our standard milk-egg combination?
Sounds like a great breakfast. It's a really good question, but let's take them separately, shall we? So which one do you want to start with? Okay, well let's start with your life-eye for chicken eggs then.
Aren't there lots of other animals that produce eggs that are edible? Totally, totally. But chickens are ridiculously productive and really well adapted to confined spaces, so essentially it's because they can be raised very quickly and they have a good size to egg produce ratio as well. Well, aren't there a lot of other animals that also produce large quantities of eggs?
Yeah, yeah, that's definitely true. There are totally other animals that produce clutches of edible eggs, including everything from turtles, geese, quails, and some more esoteric ones like ostriches, for example. Animals like ostriches produce really large eggs, but it also means they make less because a lot more energy has to go about to make them. And they're also more difficult to control if you've ever seen someone trying to control an ostrich before.
Quails, on the other hand, lay very, very small eggs, and eggshells are brittle, so they aren't really great for consumption and as a store of nutrients, even though they are quite delicacy and they do taste really good. Geese tend to live closer to water, and so they are harder to raise in the more inland country farms. How about ducks? Why not ducks?
So ducks could be a close competitor to the chicken, since domestic ducks lay nearly as many eggs as chickens, and it is possible that they could be bred to be as tolerant of confinement as chickens. But the problem is ducks still need water to clean themselves, while chickens clean their fetters with dry soil. So in modern times, it is possible to keep ducks indoors and use pesticides to kill things like fetter mites, but chickens have improved breeding because that just wasn't possible in the past. Chickens will also more reliably nest in a given space, even if they are allowed to free range.
With ducks, you'll likely have to go and hunt for their eggs. So why is it that chickens are so productive? Well, the chickens we think of today are descended from red jungle fowl. So in the forests where red jungle fowl originated, occasionally all the bamboo would drop a lot of edible seeds at once.
So what happened was that the red jungle fowl, they evolved to run their reproductive systems really excessively fast when there's a lot of food around, to basically take advantage of the bamboo seed crops. Oh, I see. So if you have a chicken and you feed it a lot, it'll basically lay a lot of eggs, because its biology thinks the bamboo seed crop just came in, and that means a lot of eggs for your kitchen. Okay, so let's turn to milk now.
How do we settle on cow's milk? If I apply the same criteria from chickens, it doesn't seem odd that cows are very large and difficult to manage compared to other alternatives. You are right that cows are much larger than other livestock that produce milk, and that means they also yield lots of milk. The only thing bigger would be the bison, which is bred in some Midwest states of the United States, but bison are also much more aggressive and difficult to herd compared to cows.
So with size also comes to the advantage of there being fewer animals to milk and provide veterinary care for. Would you say there's another alternative in goats to milk then? Ah, goats do work too, because they can eat any kind of vegetation, but if you have access to quality pasture and land with lots of grass, cows are much more productive. Then there's the other thing we haven't mentioned yet, is that beef and cow litter are much more highly valued than those products from goats.
How about the fact that cow's milk isn't homogenized? Oh yes, so to explain, milk often is homogenized in a treatment that prevents a cream layer from separating out the milk. However, cow's milk is not homogenous in nature, which means that the cream and fatty components in the milk rise to the top. Is that a good old bad thing?
Oh, it's very good, because it can be separated and then turned into something like butter. And this also adds another reason as to why cows are favorable to other animals. You know, sheep and goat milk is actually naturally homogenized, and this means the butter fat does not separate from the milk, whereas cow's milk does separate. So this allows for much easier production of butter, and butter was one of the more valuable commodities in the ancient world, which is like close fat for cooking.
Sorry to go back to this, but goat's milk is pretty popular in some parts of the world, right? Yes, that is true. In some parts of the world, people do raise goats for their milk, because they are better suited to the rocky terrain, and because some people just prefer goat milk and meat. But I guess I'd say cows pretty much have the best traits to fit with human diets, and it's pretty much all packed into one big animal.
You can still make butter from goat's milk, it just takes longer to separate it all out. Also, that butter has a lower melting point. Okay, since we're on butter, can you explain this thing called the butter line? Oh, that's an interesting one.
So there's this concept of the butter line in Europe, where as you go north far enough at a certain latitude, people's preference for cooking fat changes from olive oil to butter, somewhere around, you know, the line around northern Italy, southern France, and like halfway through Slovenia. Basically, after you go far enough north, butter left out at root temperature will last most of the year, but closer to the Mediterranean, it was spoiled too quickly to be useful. Isn't it also because you can't grow olives up there? That's absolutely another reason.
And also, butter was considered a thing for the rich in southern Europe, while oil was considered a rich thing in northern Europe. I see. Now, final question going back to the egg topic we started with. How do farmers control whether chicken lays an egg for eating, or a reproductive egg, and how can you tell which is which?
Oh, yes. So chickens lay eggs whether they are fertilized or not. So the easiest way to make commercial eggs, or eggs for eating, as you said, is to basically not allow the male roosters to mix with the female hens. But during production, eggs usually are quote-unquote candled to check your quality.
If you need to check an egg, you basically just hold it up to the right light. Got it. If you learned something new, if you did, send us an email. We are at eli5podcast at gmail.com.
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