Tatyana Granada's food tampering took place at this Calgary Co-op store. (CBC)

A woman accused of food tampering at a Calgary Co-op has been sentenced to three years in prison.

Tatyana Granada was found guilty in February on four counts of trespassing and four counts of mischief for putting dozens of pins and needles in food at the Oakridge Co-op in 2010.

The court heard she did this as an act of revenge against the store after being arrested for trespassing.

Granada had been given a verbal life-time ban from the store after she had been caught shoplifting prior to the incidents. That ban was later extended to all Co-ops in Alberta.

Judge Gerald Meagher cited a number of aggravating factors in sentencing, including her having no remorse or acknowledgment of wrongdoing, and noted the planned, deliberate and vindictive nature of the acts, which escalated over time.

The judge said she used dangerous items and caused serious risk to public health and safety, with no indication her behaviour would stop — and her children were present each time the crimes were committed.

"She's a risk to public safety, she lacks empathy and understanding," said Meagher.

Several Co-op employees submitted victim impact statements, saying they were all under suspicion, which was stressful for them. They also lost wages.

The mother of two was arrested in March 2010 after staff at the Co-op found the metal pins and needles in packaged deli cheese items and a package of flatbread.

The pins and needles were also found in bakery items, cheese, juices and some bulk food on at least two other occasions.