TOTAL Coles-brand milk sales have increased since the major supermarket discounted it's home-brand milk at the end of January.

But this recent spike indicates a trend of rising milk sales during the past decade.

This insight into Coles and its marketing strategy was provided by Coles merchandising director John Durkan at the Rural Press Club of Victoria in Melbourne this morning.

However, he would not reveal what affect this had on branded milk sales.

Mr Durkan told the crowd that the supermarket's mantra was now consumer focused - "better and cheaper quality food at Coles."

But the supermarket giant said it was still a supporter of Australian agriculture.

"Our whole aim as we said is to buy everything we can out of Australia," Mr Durkan said.

"So actually having resurgent Coles and doing what we are doing from a customer base should give us sustainability, give everyone in the supply chain sustainability."

Mr Durkan said Coles sourced all its beef, lamb and pork from Australia and tired to go as local as it could for all supply.

He said in areas such as seafood it would like to source all Australian products if it was possible.

Coles has recently come under fire from dairy industry groups, among other opposition, for discounting the price of its own-brand milk to $1 a litre.

Mr Durkan said the amount of Australia's production dedicated to drinking milk, particularly Coles supermarket-brand drinking milk which he said was 5 per cent of the nation's production, was not enough to influence the farm-gate price of milk.

"We are not the biggest driver of what happens at farm-gate, we are just not, I know that people would like to think that we are but we are not," he said.

"Actually I think we have been really responsible in how we have set up the contracts to make sure farmers get paid the right amount of money."

However, he refused to guarantee further retail milk price reductions by saying he was "not ruling anything in or anything out."

Mr Durkan said Coles had dropped the price of 5000 products in the past 12 months.

"For the last six quarters we have had deflation in our business," he said.

"We have driven that through driving prices lower and the way we have driven our prices lower is to take costs out of our own business, so we have become more efficient."

One example was optimizing the Coles supply chain.

Mr Durkan said the overhaul of Coles, in the past 2.5 years, has been about creating a "brand'' that differentiates Coles from its competitors.

Marketing strategies such as their current "down down" campaign, Mr Durkan said Coles was "starting to get some personality around the brand."

Other marketing including associating celebrity chef Curtis Stone with Coles, has inspired people to eat better quality food on a budget, Mr Durkan said.

"It's not about just cheap food, it's about quality food and cheap prices," he said.

"Our aim is to lower prices for Australian families."