For 23 of those years, Thelma has been in charge of the volunteer catering team.
She is ably supported by the other 25-year volunteer, Faye Loughridge, and a large group of helpers.
“Faye is also the scrambled eggs lady,” Thelma told Dairy News Australia.
The catering responsibilities have varied over time.
When the expo was at Poowong for its first 13 years, the catering was undertaken by a number of community groups and Thelma had to manage that.
“People would nominate themselves for two-hour shifts,” Thelma said.
The expo moved to Korumburra in 2013.
“Some of the sponsors used to have events in their marquees every year,” Thelma said.
“Our catering team would provide platters for them. We would take food across in baskets and lay it out for them.”
This year’s expo catered for the general public through the canteen, as well as a breakfast for sponsors on the second day.
The catering team also created lunch for a childcare centre’s children and teachers each day.
The local childcare centre took three groups of children through the expo.
Thelma has seen diet preferences change through the years.
“People will drink more water than soft drink these days,” she said.
This year’s expo saw the catering team provide meals from 400 bread rolls, 15 loaves of bread, 300 hamburger patties, 15kg of sausages, 15kg of onions, 24 2kg bags of chips, 40 dozen eggs and a large quantity of cheese, tomatoes, lettuce, tea, coffee, cold drinks and sauce.