Density of milk it is accepted to call the mass of milk at its temperature in 20 wasps concluded in unit of its volume. Density of milk is considered an indicator of its naturalness. Its definition requires use of special devices.
Concept of density of milk
According to the working standards, density of milk consists of density of its such components as milk fat, lactose, proteins and salts. In fact, density reflects contents in milk everything these components. It is possible to determine by density whether milk was diluted with water or not.
At gravity test of milk it is recommended to check the used equipment. It is about galactometers which on accuracy can be absolutely unsuitable for similar measurements. Also for definition of this characteristic of milk it is accepted to use professional glass areometers. By the way, this size should be determined not earlier, than in two hours after milking of a cow.
How to determine milk density?
For determination of exact density of milk it will be required to prepare a measured cylinder on 250 ml with a diameter not less than 5 cm and the galactometer. Also it is necessary to learn whether the galactometer was checked in laboratory of measures and measuring devices. Surely study results of this check. If with the device everything is all right, it is possible to start measurement of density. Take the milk made for the analysis, accurately on a stenochka pour it in a cylinder up to 2/3 volumes. At the same time you watch that during a nalivaniye foam wasn't formed. Then take the dry galactometer and lower it in milk. The device has to be in absolutely free floating state. Approximately in a couple of minutes of fluctuation of the galactometer have to stop. It will mean that time to count density and temperature of milk on the upper edge of a meniscus came. At the same time an eye has to be at the level of the line of a meniscus. Make measurement two times. Surely slightly rock the galactometer and find an arithmetic average from two definitions. It is strongly recommended to determine the relative density of milk at its temperature in 20 wasps. If it was higher, to indications of density it will be necessary to add 0.0002 by each degree. At fall of temperature this value, on the contrary, has to be subtracted. By the way, in state standard specification there is even a special correction chart on milk test methods. It turns out that gravity test of milk won't require any specific knowledge. It is enough to study the sequence of actions only in detail.