Today, we are talking about the life cycle of the humble raisin, from farm to fork. Across the world, raisins (and sultanas, for that matter) are produced largely in the same way, from the same group of grape varieties. This accounts for all of the major origins, but the ones we will be focusing on are Turkey and South Africa, as these two origins make up the majority of UK and EU imports.
To get started, let’s have a look at the type of grape used to make raisins. Typically, the raisins and sultanas that you see on shelves and in baked goods are dried Thompson Seedless grapes. This white grape is primarily used because its high sugar content and thin skin make drying easy, alongside the fact that they are abundant on the vine. Other grape types are used, but in far smaller volumes than Thompson Seedless. One of these is the Flame variety. This is a red grape, often used for wine in Chile and South Africa, that produces larger fruit than the Thompson Seedless. This has a knock-on effect on the raisins, making them far larger than your average Turkish raisin. Now that you’re awake, let’s move on to the drying processes.
Traditionally, grapes are dried in two main ways, and there are no ovens involved. The most prevalent method is sun drying. Once grapes have reached their desired sugar level, they are harvested, usually by shaking the vines, and laid out on drying beds on the ground in the vineyards. Over the course of two to three weeks, the sun dries out the fruit, concentrating the natural sugars and turning the grapes into raisins.
In Turkey in particular, a large portion of the crop is turned into sultanas. Sultanas are raisins that have been dipped in potassium carbonate, which helps them dry faster. This is because the solution makes the skin of the fruit thinner, providing less insulation from the heat of the sun and allowing the grape to dry more quickly. This is also the reason that sultanas are lighter in colour, as the thinner skin means that more visible light passes through the fruit, making the sultana appear lighter in colour.
The second method of drying that is widely used is drying on the vine. As the name suggests, the grapes remain attached to the plant while the drying takes place. Growers partially cut or treat the branch supplying the grape bunches, reducing the flow of nutrients and moisture. With the reduction in nutrients and moisture, the fruit then begins to dry naturally while still hanging on the vine. While this method can reduce labour requirements and often produces a cleaner-looking raisin, it is very condition-dependent and requires careful vineyard management and favourable weather conditions.
So, raisins are dried grapes. Before being ready for eating, raisins need to undergo some processing, primarily cleaning and sorting. This process removes stems, cap stems, foreign materials and any other loose matter. Primarily, this is done using a series of washes, blowers, X-rays, metal detectors and manual checks on the line. Processors, like our suppliers, are capable of sorting fruit by size, colour and quality with truly remarkable accuracy, given the small size of the fruit.
Our suppliers specialise in tight specifications, so things like the lowest possible microbiological levels, specific moisture levels and pasteurisation are all possible for companies that we can supply in the UK.
From here, the journey is nearly complete. The fruit is packaged, shipped and unpacked, ready for use on production lines across the UK and Europe. Whether from vineyards in Manisa, Turkey, or along South Africa’s Orange River, each raisin begins on a vine before travelling by road, sea and distribution networks to factories, bakeries and supermarkets. Ultimately, it arrives in front of you, ready to eat.