Tomato Juice

The Tomato juice obtained by grinding and sieving and by removal of waste is a suspension of finely divided pulp in a yellowish liquid (serum), containing the tomato savory, compounds and aromas. The pulp is mainly formed by the membranes of the fruit's cell; the substances dissolved and suspended in the juice contribute to the total dry matter content (4 to 7%). Average composition of tomato juice:

		%
water	93.00	-	96.00
sugars (glucose, fructose)	02.00	-	03.50
acids	00.25	-	00.50
insolubles (cell, pect.)	00.70	-	01.00
amino acids & proteins	00.60	-	01.20
mineral elements	00.30	-	00.60
sod. chloride	00.05	-	00.15

The yield in juice extracted from the tomato depends on variety, form and dimensions of the berry. Furthermore it depends on the conditions of ripeness integrity, and on the preparation technique. This does not take into account the tomatoes rejected in the sorting line as not suitable for transformation.

In the humid state, one can value a yield in 97%, in respect to the tomato, with the remaining 3% being waste (peels and seeds).

Tomato juice is utilized as a beverage, either directly or in a mixture, such as cocktail drinks. The Italian legislation defines it as a non-concentrated juice, obtained by squeezing and refining pressed tomatoes.

A tomato beverage must have the following characteristics:

• color, taste, and aroma typical of the fresh fruit
• correct fluidity
• maximum preservation of nutritional properties of the fresh fruit
• it is generally produced with the addition of salt to increase the sapidity and is packaged in cans, aseptic cartons, or glass bottles.

A production line of drinkable juice includes:

washing and sorting

trituration

possible reheating

extraction & refining

de-aerating

de-aerating

HOMOGENIZATION

filing & sterilization (or vice versa)

cooling

High Pressure Homogenization

High Pressure homogenization is an entirely mechanical process; the product is forced by a high pressure piston pump through homogenizing valve. The Niro Soavi homogenizer is suitable for treatment of products having aggressive chemical characteristics (due to the presence of organic acids) and can stand the mechanical action caused by the presence of solid particles in the product.

During homogenization, particles of various nature are crushed:

• single cells
• cellular aggregates
• agglomerate crystals (sugars and salts)
• globules of essential oils
• various other structures (fats, woods, fibers, etc.)

By homogenizing, the dimension of the suspended particles is reduced. At the end of the process, the suspension presents a uniform distribution, according to a "Gaussian" curve, which varies with operating conditions.