Natasha Marie Harris, 30, of Invercargill, died on February 25, 2010 after a cardiac arrest. There was also a lack of potassium in her blood.
At the time of her death her partner, Chris Hodgkinson, said it was the result of drinking too much Coca-Cola - a claim the company has rejected.
In a ruling made public today, Otago-Southland Coroner David Crerar noted Coca-Cola was more than a week late in advising it would attend an inquest into her death.
Counsel for the company was present at the hearing and chose not to submit any evidence.
But the company later applied to submit evidence, noting it was "surprised'' that pathologist Dan Mornin had gone further than merely reading his autopsy report at the hearing.
Coca-Cola also requested samples, taken at Ms Harris' post-mortem examination, so they could be assessed by another forensic pathologist.
Coroner Crerar granted the request, noting a refusal would be a breach of natural justice, and gave the company until July 31 to report back.
"The additional distress to the family of Natasha Harris this delay will necessarily create is regrettable,'' he noted.
But the company did not report back by July 31 and, in a ruling dated the day before the deadline, Coroner Crerar gave Coca-Cola a one-month extension.
No reason for the extension was given, although the ruling noted "all actions required'' for the transfer of samples had been completed by July 25.
Coroner Crerar said in his ruling that all costs of the extra testing were being met by Coca-Cola.
