He attracted a bidding war for the purveyor of Ball Park frankfurters and Jimmy Dean sausages, and eventually sold it to Tyson Foods last year for $7.7 billion. There may be some appetite for ConAgra's various morsels. Analysts at Credit Suisse estimate that the various parts — including branded and frozen foods, private-label goods and another division that sells French fries to fast-food chains — could be worth $42 to $43 a share in a full breakup. The rise in ConAgra's shares on Friday put them right in that zone.