You can extract Casein out of the milk and make a rock hard polymer type plastic out of it using just vinegar. One cow produces 20,000 pounds of milk per year so with a small heard you can make a shit load of this stuff its easily mouldable when wet and hardens when it dries. SO you can make a dome house out of it and eat it if times get tough. Buttons and knitting needles and the like are made from it. I know back in the day the Canadian forces used them on the uniform buttons on combat colthing and parkas so you could eat the buttons in a jam. You can make a plastic glass out of potatoe starch or any starch for that matter that is trans lucent. Just google Plastic from milk or plastic from starch. Called bioplastics but dead easy to make and use.
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