Menlo Park-based private equity firm Accel-KKR said Tuesday that it has acquired a majority stake in Pleasanton-based iTradeNtework. iTradeNetwork is a provider of software-as-a-service for the food industry. Financial terms of the acquisition were not disclosed. According to Accel-KKR, the firm now holds a majority of the equity, with private equity firm ABRY Partners and employees holding the remainder of the firm.