To have a successful interview, whether in person or by phone, you must be thoroughly conversant about the interviewing company and its products. This calls for you to put all your best research skills to work, including talking with acquaintances who have worked for or with the firm in question.
Food scientists have one major advantage over job seekers in other fields. A tremendous amount of industry intelligence can be gathered while you pick up a bottle of milk at the corner store.
(The Internet is a useful tool, but don't trust it to be comprehensive or totally accurate. Plan to spend at least a few hours in library stacks scanning in-depth articles and industry directories.)