Greggs try to donate as much unsold food to charity as possible, including soup kitchens, food banks, and shelters for the homeless and vulnerable. If you are a good cause which would like to be considered for their food donation programme, use the link below to find their application form:
Unsold Food Donations | Greggs Foundation

Warburtons provide one off food donations for some charity events; click here to find details and their application form: 
Product Donation | Community | Warburtons

Work with food retailers and businesses to redistribute surplus food to social enterprises:
Neighbourly.com

Here are some useful links to help you recruit and manage volunteers:
How to manage your charity's volunteers - GOV.UK
Training volunteers | NCVO
Find a Volunteer Centre | NCVO

25% Discount

for all charity and volunteer organisations on training courses