Here's a list of businesses (and their ratings) in the Manufacturers/packers category.
In England, Wales and Northern Ireland food hygiene ratings are provided by the The Food Hygiene Rating Scheme (FHRS). Ratings in Scotland are provided by a similar scheme called the Food Hygiene Information Scheme (FHIS).
You can read more about FHRS and FHIS food ratings here.
Click on a establishment below for more information:
Radwell Mill House Radwell Lane, Radwell, Hertfordshire, SG7 5ET

Total Score: 10 (lower is better)
14 Green Lane Industrial Estate Green Lane, Letchworth Garden City, Hertfordshire, SG6 1HP

Total Score: 5 (lower is better)
Lannock Manor Farm Hitchin Road, Weston, Hertfordshire, SG4 7EE

Total Score: 5 (lower is better)
Greys Farm Therfield Road, Royston, Hertfordshire, SG8 9NW

Total Score: 20 (lower is better)

Total Score: 10 (lower is better)