Geoffrey Hocking, 55, and Patricia Davis, 53, made unsuccessful, self-represented bail applications in Warrnambool Magistrates Court on Monday and were remanded in custody until August 21.

The pair were arrested at Tyrendarra at the weekend after police allegedly found a commercial quantity of heroin in their possession.

Portland police Senior Constable Alex Gettens alleged the pair were "a big part of the heroin trafficking scene" in Portland and surrounding areas.

He said on May 8 police intercepted a white Toyota in Tyrendarra about 10am.

Ms Davis was driving the vehicle and Mr Hocking was a passenger.

Senior Constable Gettens said police announced that a search would be conducted and the pair exited the vehicle.

Ms Davis told police she needed to go to the toilet before crouching behind a tree.

A search of the area later located a small box tucked into grass near the tree.

Police uncovered 59 grams of heroin and a small amount of cannabis inside the box.

The heroin had an estimated street value of nearly $30,000, the court heard.

Ms Davis allegedly told police she purchased the heroin from a Melbourne man for "a couple of thousand (dollars)".

She said she had no intention to sell the drugs and that it was for personal use.

But Senior Constable Gettens said it was unlikely one person would be able to consume 59 grams of heroin, which he said would amount to up to 500 "hits".

"It was a significant amount, I'm not sure an individual would be able to use it in a reasonable amount of time," he said.

Meanwhile, Mr Hocking denied the offending, stating he was simply a passenger in the vehicle and wasn't in possession of the drugs.

He urged the magistrate to grant him bail, stating he needed to get home to collect his pet python that was free-range in his bedroom.

Magistrate Mark Stratmann said the pair failed to show exceptional circumstances why they should be released from custody and bail was refused.

Portland Sergeant Ash Rawlings said the seizing of a commercial quantity of heroine was a great result.

"This is a large amount of heroine, you can't get more serious than this," he said.

"It's a great result for us.

"This was proactive policing at its best."

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