Yield: 1 Batch
To obtain good quality in the canned juice, use only freshly picked, tree-ripened fruit. Ream the juice from the fruit by using a cone shaped juice extractor. This will help to keep rag, cell tissue and oil out of the juice. These will affect the color and flavor of the canned juice. After extraction, the juice must not be allowed to stand exposed to the air. The entire procedure from extraction of the juice to processing must be carried on without delay.
Wash the grapefruit, cut in half and extract the juice. Strain out seed and coarse pulp. Work rapidly to avoid exposure to air. Pour into clean jars to within ½ inch of top of jar. Put on cap, screwing the band tight. Process in water bath for 20 minutes at simmering temperature.
Source: Kerr Canning Book