Traditional fermentation processes are increasingly attracting the attention of scientists and policy makers as a vital part of food security strategies. New opportunities provided by biotechnology are opening up possibilities to improve or upgrade traditional small-scale processes and make better use of agricultural products. A straightforward transfer-of-technology approach, characteristic for mainstream development assistance to developing countries, is inappropriate to upgrade and improve the traditional food processing sector in developing countries. In this paper, the case of soy sauce fermentation in Indonesia is presented to illustrate the dangers of narrowing traditional food processing to a sequence of operations. These processes and their operations reflect the social, political, cultural and ethnical relations in which they emerged and evolved. Successful upgrading requires that these relations are understood and that, based on such an understanding, modern technologies build upon their traditional predecessors. Any technology or project that neglects the coherence between these relations or is unable to meet social, political and cultural requirements in addition to technical ones, is doomed to fail.