Cranberries are grown in bogs, the plants are called vines. However they are more like small bushes. Cranberry bogs are expensive to create but use poor land, once made into bogs they can’t readily be converted back. Sand is a very important constituent of the soil makeup. At harvest the bogs are flooded and the berries are agitated from the vine, the float due to air pockets in the berries.
In the northern hemisphere the growing season is over the summer and harvest is September or so. In the southern hemisphere they harvest in March. The cranberries must be stored in the freezer for 2 months or so to break down the internal structure of the fruit which aids the infusion process.
The cranberries are harvested from the bogs and washed. This removes the stalks and leaves from the field. Washed goods are then sorted and frozen. Berries removed at this stage will be sent to make concentrate.
The sorted, frozen berries are sliced to give a good clean cut. Sweetened Dried Cranberry facilities run process concentrate in tandem. This makes both end products more financially viable. Some juice is removed from the berries before infusing.
The sliced, frozen berries are placed in a tank of hot water to remove some juice from the berries, this is taken to the concentrate facility. The berries are then added to a sugar solution to replace the lost juice with sugar solution. The sugar acts to sweeten the berry to make it palatable and also acts as a preservative.
The cranberries are drained of syrup and then washed (some processors may not wash at this stage to remove excess syrup). The syrup is cleaned and reused.
The drained, infused berries are dried in a continuous dryer to create a stable, dry product.