How is jam made?

Džem je proizvod odgovarajuće želirane konzistencije, proizveden od šećera, voćne pulpe i/ili voćne kaše/pirea dobijene od jedne ili više vrsta voća i vode, koje se kuvaju na temperaturi od 103-104 °C do uspostavljanja želatinaste strukture.

The amount of fruit needed to make jam

The quantity of fruit pulp and/or fruit mash/purée used for the manufacture of 1,000 g of the final product may not be less than 350 g for all types of fruit, except for 1) red currant, rowan (Sorbus aucuparia), sea-buckthorn (Hippophae rhamnoides), black currant, rosehip and quince, which require 250 g; 2) ginger, which requires 150 g; 3) cashew or cashew apple (Anacardium occidentale) for which 160 g is required; 4) passion fruit (Passiflora edulis), which requires 60 g.

If you use larger quantities of fruit, instead of industrial jam you will make extra jam, which has slightly different characteristics, and differs from industrial jam in the amount of dry matter used to make it: industrial jam must not contain less than 35% of dry fruit matter, per kilogram of the final product, while extra jam must not contain less than 45% of dry fruit matter, for the same amount of the final product.

Extra jam from rose hips, raspberries, blackberries, black and red currants, and seedless blueberries can be produced in whole or in part from non-concentrated fruit purée. In the production of extra jam, it is not allowed to mix the following types of fruit with other fruits: apples, pears, plums, melons, watermelons, grapes, pumpkins, cucumbers, and tomatoes.

The amount of fruit needed to make extra jam

The amount of fruit pulp used for the production of 1,000 g of the final product may not be less than 450 g for all types of fruit, except for 1) red currant, rowan (Sorbus aucuparia), sea-buckthorn (Hippophaerhamnoides), black currant, rose hip and quince, which requires 350 g; 2) ginger, which requires 250 g; 3) cashew or cashew apple (Anacardium occidentale) for which 230 g is required; 4) passion fruit (Passiflora edulis), which requires 80 g.

Processing the fruit before cooking the jam

Before cooking the fruit mass and sugar and adding pectin and acids, the fruits should be adequately prepared and processed. In the first place, fresh fruit must be of excellent quality, selected fruits, and well washed because it directly affects the color and aroma of the jam. After washing the fruits, the stones are being removed, if there are any. Removal (separation) of stones from plums, apricots, pears, apples, and other fruits is simply done with mashers, which, as the name suggests, mash the fruit.

They are used to produce pure fruit mass, which is ready for further use without the influence of fruit stones. When making fruit jams that need to be shredded beforehand, such as plums, quinces, apples… mills are used – machines for grinding, crushing, and shredding that speed up the process of obtaining a mass that is ready for further processing on fruit purées. For the jam to have better color, it is allowed to add up to five percent of fruit juice or other types of fruit, about the total amount of fruit substance from which you make jam.

What sugar is added to the jam?

The prepared fruits are then cooked with the addition of sugar. Sugar sucrose is used in the preparation of jam, which can replace sugar syrup, dextrose, dextrose syrup, or fructose, but also glucose and glucose syrup, which you can use up to 30 percent of the amount of sugar, to prevent its crystallization. The amount of sugar you will need will depend on the acidity of the fruit, the sugar content of the fruit, the degree of ripeness of the fruit, and the type of product.

What is the use of pectin in the production of jams?

To form a quality gelatinous structure, pectin is used in the production of jams, a dietary fiber that is found in the cell walls of plants, and which can create jelly. Pectin can be bought, but it is much healthier to make it, and jam is added to the mixture from which you cook before the end of cooking.

Use acids for a better taste of jam

In addition to pectin, to achieve a pH value that is optimal for creating a gelatinous structure, citric and malic acid are added to the jam, and sometimes tartaric. In this way, they simultaneously improve the taste of the jam and have a preserving effect because they prevent the development of pathogenic bacteria.

Jam packaging and storage

At the end of the process, the mass is heated to boiling, to perform pasteurization. After that, the jam is poured into the packaging (usually glass jars) and its temperature must not be below 80 degrees so that mold does not appear. For the same purpose, lamps with UV or IR rays can be placed above the conveyor belt through which the jam passes from the machine for filling to the machine for closing the jars. It is not necessary to store the jam at low temperatures, since it contains a large amount of sugar, which is its property due to which it is not prone to spoilage and does not require sterilization, but only pasteurization.

Signs that you made a mistake somewhere during the preparation

If the jam gets too dark and tastes like caramel, it means that you have overcooked it, but it is still edible. If you feel alcohol during the trying phase – the jam should be boiled. If you notice that the sugar has crystallized, the fruit lacks acidity, which you will solve by adding lemon juice and overcooking the jam. In case mold appears on the jam – some of the utensils and dishes you used to cook the jam were not sterilized. When this happens, you need to remove the mold, boil the jam and transfer it to clean jars.