CHICAGO - Wakefern Food Corp., Elizabeth, N.J., is expanding its Partners in Training program to Philadelphia next month with ABO Haven, a social service agency that provides job training for people in the inner city. Martin Glass, Wakefern’s senior manager, human resources, detailed the program, which won the Food Marketing Institutes Maxx Award last year, to FMI attendees yesterday. Wakefern invests $80,000 to set up job training sites through agencies, including Good Will Industries and New Community Corp., to train unemployed and underemployed people. In the seven years that Wakefern has run the partnerships, the co-op wholesaler, which serves nearly 200 ShopRite stores, has placed over 600 people in 17 ShopRite supermarkets in New Jersey and Delaware. Wakefern initially expects to train between 12 to 15 people as cashiers to work in the Philadelphia area.