Tatyana Granada was found guilty last year of mischief and trespassing for placing needles, pins, nails and other objects into bread, cheese and produce at the city's Oakridge Co-op.
She was sentenced to three years in prison.
She was challenging the mischief convictions in part by suggesting the judge wrongly considered evidence from an expert in body mechanics.
The expert was brought in to comment on Granada's arm movements that were caught on video while she was in the store.
The Alberta Court of Appeal ruled the judge did not err in accepting the expert's opinion.
The food tampering began after Granada had been charged with shoplifting at the store and barred from it and all other Co-ops.
Co-op estimated it lost at least $600,000 in business and in costs associated with the investigation.
(CHQR, The Canadian Press)
Also on HuffPost