In Parliament on Tuesday Mrs Britnell said rumours of a large payment from the co-operative to her business were untrue.

It comes after former Greens MP Greg Barber questioned the family's decision in the upper house.

"There is a lot of speculation in the community ... about my family's decision to stop supplying milk to Murray Goulburn," Mrs Britnell said. "I want to set the record straight. There are rumours of a large payment to us from Murray Goulburn in an effort to retain our business.

“There is absolutely no truth to this suggestion. It is completely false, and I am quite happy to open our books to anyone to prove this point."

 She said her farm had supplied Murray Goulburn until September 14, 2017. 

"The following day we started supplying Warrnambool Cheese and Butter," Mrs Britnell said.

"There is nothing untoward, and we worked with Murray Goulburn through the transition process."

She said her family business did not benefit from staying beyond the date that was quoted in The Standard, when they publicly announced the move.

Mrs Britnell said she wished Murray Goulburn all the best.

"They are very important to the Australian dairy industry, but unfortunately we had to make a very tough call to do what was right for our family and our business," she said.

"Those who want to say otherwise ... might do well to speak to me personally rather than continuing to trade in rumour and innuendo."