The son of Russian immigrants, Eisenstadt was born in 1906 on the Lower East Side of Manhattan and appeared headed for a career as a lawyer after he graduated from St John's University law school in 1929. The Depression spoiled his chances and he took a job working in his father- in-law's cafeteria before opening one of his own, the Cumberland, near the naval shipyard in Brooklyn in 1940.
Providence struck again when the end of the Second World War left Eisenstadt bereft of customers and, recalling an uncle who had once operated a company that filled tea-bags, he turned the cafeteria into a tea-bag factory, the Cumberland Packing Company. Overwhelmed by existing suppliers and faced with another business failure, Eisenstadt realised that the same equipment could be used to put sugar in little paper bags.
At a time when restaurants still used open sugar bowls and sugar spoons his idea was revolutionary. Unfortunately Eisenstadt was still naive and showed his invention to the existing sugar giants who promptly set up their own sugar-packet productions and soon had America, and later the world, shaking its sugar before sweetening its hot drinks.
Eisenstadt's luck changed in 1957 when, tinkering with his chemistry-educated son, he mixed saccharin, which was only available as a liquid or pill and restricted for use for diabetics and the obese, with dextrose. Taking care to patent what was the first granulated low-calorie sugar substitute, he named the product Sweet'N Low after the Tennyson poem and distinguished it from white sugar packets with a pink packet printed with a treble-clef musical logo.
This time his timing was perfect and he rode the crest of the 1960s health craze to fortune. He later developed an even lower-calorie sugar substitute branded Equal and sold in blue packets, as well as a butter substitute, Butter Buds, and a salt substitute, Nu-Salt.
Despite increased competition, the company, which still manufactures on the site of the cafeteria, turns over $100m a year, employs 400 people and turns out 50 million packets of Sweet'N Low a day from a global web of plants including ones in England, India, Israel and Canada.
Benjamin Eisenstadt, entrepreneur and philanthropist: born New York 23 December 1906; married Betty Gellman (two sons, two daughters); died New York 8 April 1996.