See quotations.

1

1883.  In the Far West, as Down East, sugar bears the name of long and short sweetening, according as it is the product of the cane (known also as store-sugar) or of the maple tree.—‘Supplement to the Encyclopædia Britannica,’ i. 199/2, ‘Americanisms.’ (N.E.D.) (Italics in the original.)

2

1904.  Only cornbread, peas, and sorghum were plentiful. The latter took the place of molasses, and at the same time was known as “long sweetening.”—J. H. Claiborne, ‘Seventy-Five Years in Old Virginia,’ p. 201.

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