But with some quirky advertising and some "outrageous claims", Jamie Callister said the Australian spread has "survived the test of time".
It has been 100 years since Cyril Callister invented Vegemite as an alternative to Marmite.
Marmite had become scarce due to German U-boats sinking the ships bringing the English spread.
From humble beginnings to annual sales of more than 22 million jars, the yeast-based product has become a fixture of culture down under.
Jamie Callister said there were clear differences between the two spreads - with Marmite being much sweeter than Vegemite.
But it took a while for its popularity to really take off.
"When it first rolled off the production line, no one even really liked it," he said.
It was not until entrepreneur Fred Walker, who helped create the spread, had a "stroke of genius" and began giving a jar away with his "ever popular" processed cheese that people really started to taste it.
The war played an "enormous part" too, Jamie Callister said.
"It was written into the Australian army ration book, so it's success was almost assured like a flick of a pen because Vegemite was then sent away, abroad, for the troops overseas and those at home, as you said, had to go without and people were really hooked on it by then.
"Absence makes the heart grow fonder so they really started to long for their Vegemite that they couldn't get their hands on."
Callister said people had been cooking with Vegemite for a while now and it had a real place in the kitchen.
"I use it when I cook a roast, I'll put vegemite on the top, make the gravy out of it, and use it in some other things but it goes well with cooking."
