Australia's strawberry industry, worth A$160 million (US$116 million), was rocked in September after almost 200 complaints were made of sewing needles found in strawberries and other fruits.
Detective John Walker of the State Crime Command said she worked in the strawberry industry near the town of Caboolture, north of Brisbane.
An Australian court was told on Monday that a former strawberry farm supervisor retaliated over a workplace grievance by contaminating cases of strawberries with needles in a case that gripped the country.
The woman accused of sparking the strawberry needle saga faces a maximum 10 years' in prison if found guilty of contamination of goods.
At least six brands of strawberries, Donnybrook Berries, Love Berry, Delightful Strawberries, Oasis, Berry Obsession and Berry Licious, were recalled and several chain supermarkets pulled all strawberries from their shelves.
The "unprecedented" scare spread to every Australian state and later to New Zealand, raising public alarm. Metal was also found in a banana, an apple and a mango, which the government believed to be isolated "copycat" cases or hoaxes.
The woman was arrested this afternoon and has been charged with seven counts contamination of goods under Section 238 Criminal Code, which has a three-year maximum penalty.
Strawberries made up 3% of Australia's fruit exports for the year ending June 2017, according to the Australian Bureau of Statistics.
The Queensland Strawberry Growers Association (QSGA) has welcomed Trinh's arrest, but called for copycat offenders to also face charges.
The first incident was reported in September when a man in Brisbane was hospitalised after swallowing half a needle and complaining of severe abdominal pains.
The court was told she was motivated by spite and revenge when she allegedly inserted the needles into the berries in early September, the Australian newspaper reported.
The investigation was continuing, he said.
Police did not reveal the reasons and motives behind her alleged involvement.
Superintendent Wacker said the case was finally broken open upon information received by Victoria Police as part of the interstate investigation.