A Subway spokesperson has said immediate action has been taken to rectify the issue highlighted by officers.
The store on Town Lane was found to have an unsatisfactory level of hygiene, with inspectors requesting it be thoroughly cleaned.
In their report, officers noted:
Inspectors were told that the bread cutting knives should be changed every 20 minutes but during the inspection, they had not been and were dirty with old food debris.
Another problem inspectors highlighted was a lack of hygienic hand drying materials at the wash handbasin and advised alcohol-based sanitiser could not replace hand washing.
The wash handbasin in the food preparation area had a bag of frozen chicken defrosting in it.
Officers had noted at previous inspections issues with food being stored at unsuitable temperatures and found it again at their latest visit. Turkey, a high-risk food that should not be stored above 8C, was stored at 9.6C and the salsa sauce was also probed out of temperature.
All food that had been identified out of temperature was disposed of voluntarily during the visit.
During the inspection, there was no manager or supervisor present and officers said it was clear the staff had not been provided with instruction in food hygiene policies and practices in relation to hazard analysis.
Inspectors also found there was not a suitable hazard analysis in place but were told after the visit it was being rectified.
A spokesperson for Subway has said: "The health and safety of all guests is of paramount importance to Subway and all stores are regularly audited to ensure compliance.
"Subway Franchise Owners are expected to maintain high food safety standards in their stores, and the franchisee of this particular store has taken immediate action to resolve this issue and another inspection has been scheduled and paid for.
"Once available we look forward to sharing the result of the reinspection."