After a closure of almost a month, the Hershey chocolate factory in Smiths Falls, Ont., is scheduled to reopen next week.

The plant, about 60 kilometres southwest of Ottawa, was shut down Nov. 9 after a routine inspection detected salmonella, a type of bacteria that causes food poisoning.

Twenty-six of the factory's products were later recalled, including various sizes of Oh Henry! chocolate bars, Reese Peanut Butter Cups and Hershey Chipits chocolate chips.

Company spokeswoman Stephanie Moritz said Hershey was contacting the plant's 500 employees Friday and many of them will be back on the job Monday. The rest will be back later in the week, but their start day will depend on their shifts and jobs. The chocolate shop attached to the plant will also reopen Monday.

Moritz said the plant will begin production next week using a new supplier of soy lecithin, the ingredient the company found to be the source of the contamination during its internal investigation. Soy lecithin is an emulsifying agent used to help chocolate flow during the manufacturing process.

Garfield Balsom, who is with the office of food safety and recall at Canadian Food Inspection Agency, said the agency completed its investigation of the contamination and agrees that the soy lecithin was the cause.

Moritz said the company worked closely with the agency during the shutdown in order to clean the plant.

"All of the equipment and production lines at the plant were sanitized, just to ensure that our facility meets our high-quality standards," she said.

Many of the employees temporarily laid off were brought back to help with the cleaning.

Symptoms of salmonella poisoning include high fever, severe headache, vomiting, nausea, abdominal pain and diarrhea.