# Calculating the concentration of solutions intended for food preservation, processing and the importance of measuring them

The food processing requires both at home processing Or within the factories to use Large amounts of sugar and salt reach thousands of kilograms per day. and we know that sugar is expensive and the increase or decrease in the necessary amount of sugar and salt harm the product And it is classified from the factors of

A suitable method had to be found to prepare the solutions are meticulously accurate without making mistakes and the calculation method is simple and fast

we consider that the concentration of sugary and brine solutions Which is included in the food manufacturing process is one of the most important things that must be taken care of because

A - Increasing consumption of raw materials, which raises the productive unit ..For example ... a factory consumes 5 tons of sugar.. 1% mistake of calculating It causes a loss of about 50 kg of sugar The more quantity used, the greater the loss.

B - mistaking in the measurement of  solutions concentration  leads to use less    preservative concentrated solution so that , this leads to damage and corruption in the products As it is known, by mistake in Calculating the concentration , the product controverts food standards

## How to measure the concentration of sugary  and saline solutions

It depends on two bases
• Determination of the density of sugary and saline solutions Because there is a relationship between the concentration and the density of the solution, The density of sugary and saline solutions is directly proportional with its concentration, In the alcohol solution, the density is inversely proportional to the concentration
• Measurement of the refractive index of light

### Methods of measuring and estimating density

Density is the mass of one volumetric and it  is known about G / cm3, kg / dm3, tons/ m3 are calculated

•  As the density of pure water is equal to one At a temperature of 4 ° C
• The density of pure sucrose is 1.588g / cm3 The temperature is 25 ° C Any 1 cm3 mass of sucrose is equivalent 1.588 g
•  The density of NaCl is 2.165g / cm3 At a temperature of 25 ° C

the density estimation is correct If the solutions are made of one dissolved matter  and one solvent
Sugar and water or salt and water

and it is difficult to calculate Density if it is solid and gaseous materials, so the specific weight is calculated due to the effect of density by heat Specific weight

Weigh a specific volume of solution
= ___________________________________
Weigh the same volume of distilled water

at a certain temperature

Note:

The density of distilled water   = 1g / cm3 at Temperature {4+ C} ،
The specific weight of the material (Solution) = density of substance (solution) At a temperature of +4 Where there is a relationship between the density of the solutions and their concentration
Or its specific weight at different temperatures

#### Methods of measuring the density and concentration of sugary and saline solutions

1. pycno  meter
2. Hydrometers
3. Westphal Balance
4.  Refracto meter

### pycno meter

•  It is one of the methods of very accurate measurement in measuring specific weights. First, a specific volume of the liquid that we want to know is weighed in addition to the weight the Same volume of distilled water And that is at a constant temperature
•  The pycno meter is known to be precisely sized and its size is 50 cm3..it has a neck made of fine polished  glass in addition to a stopper inside which there is a capillary tube  to get rid of any solution in excess of the size 50 cm3

#### For the work steps:

•  First - We weigh the previous bottle, which is empty, clean and dry. We record the weight ... we symbolize it for example (a
•  Second - we fill the bottle with distilled water We dry it from the outside and record the weight... we symbolize it (b
• Third - We empty the bottle and wash it with the liquid whose specific weight is to be known several times, then fill it with this liquid, dry it and then weigh it. . We denote the resulting weight (c

We have the specific weight as follows:

Weigh a specific volume of solution
= ____________________________________

Weigh the same volume of distilled water