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"The Basic Prune Juice Manufacturing Process
1. The prunes are washed and placed in a cooking tank along with the appropriate quantity of water.
2. The contents of the cook tank are then heated and stirred until the prunes mostly dissolve and the sugars go into the water to make juice. This can take from several hours to as much as a half a day (12 hours).
3. If viscosity reduction is required, enzyme is added at this point.
4. The juice is then strained or filtered to remove the pits and the un-dissolved solids.
5. The finished juice is then canned, bottled or made into prune juice concentrate.
6. For canning and bottling, the process is a hot fill and hold at 190°F. "