How to check the quality of staple foods: simple ways

Unfortunately, very often the quality of food leaves much to be desired. Therefore, in order to check this quality, it is good to have a couple of secrets in stock.
The freshness of eggs
You can check it with a glass of water: a fresh egg will lie on its side on the bottom. A week-old egg will turn its blunt end up, and an old one will float to the surface.
Milk
Combine milk and alcohol - 1:2, shake and pour into a saucer. In good quality milk, white flakes will appear. If the flakes appear late or not at all, the milk has been diluted with water.
If you add a few drops of iodine to the milk and it turns blue, it means that starch has been added to the milk.
Sour cream
If you mix iodine with sour cream and it turns blue, it contains starch.
You can also dilute a spoonful of sour cream in a glass of hot water: if white clots appear on the surface, it means that the sour cream contains vegetable fat.
Cottage cheese
Drop iodine on the cottage cheese - if it turns blue, it's low-quality, if it turns red, it's good, you should buy it.
You can pour a little boiling water into the cottage cheese - if greasy spots appear on the surface, the cottage cheese contains vegetable fats.
Or leave the cottage cheese at room temperature: if it becomes covered with a yellow film, but the taste and smell do not change, then it has vegetable fats.
Butter
Boiling water also helps determine the quality of the butter: good butter will melt and spread in no time, but margarine and spread will fall to pieces.
Honey
Honey is often faked: chalk, starch, water, and flour are added. Dissolve honey in water and add a little vinegar - if it starts to hiss, it contains chalk.
If you pour a little honey on paper and it spreads and forms a large wet trail around it, it contains water.
Candied fruit
Dip candied fruit in boiling water - if the water turns colored, the candied fruit is not quite natural.
If the candied fruit is slightly or even completely dissolved in water - it was gelatin + dyes, or the fruit was overcooked, it is useless.