Which is correct, “these” or “this” molasses?

Molasses is derived through Spanish from Latin mellaceus, “honeylike.” Since, the singular and plural forms are spelled the same, the word is often construed as a plural when it should be construed as a singular. Molasses are, these molasses and those molasses are common expressions, especially in the South and West. They are incorrect except in those rare cases when the speaker or writer has in mind different kinds of molasses and really desires to use the word in the plural. “These molasses are good” is not correct when the speaker refers to molasses in a container on the breakfast table. The correct expression, of course, is, “This molasses is good.” On the other hand, it would be technically correct, though awkward, for a merchant to write, “Please send me ten gallons each of those two molasses I ordered last year,” when he refers to different kinds or brands of the product.