Barriers to implementing process analytical technology in keg cleaning: a multi-stakeholder qualitative study in the brewing industry

Keg cleaning is essential for hygiene but requires substantial water, energy, and chemicals. Process analytical technology (PAT) could adapt cleaning to actual contamination levels. In adjacent sectors, PAT-based cleaning has demonstrated water savings up to 35% and energy reductions exceeding 50%. However, despite this potential, we identified no documented sensor-based keg cleaning implementation in the literature or among experts, and therefore no comparable savings figures for kegs. To understand this gap, we conducted semi-structured interviews with 14 experts from breweries, OEMs, suppliers and research. The technology-organisation-environment framework served as the principal analytical lens, with transition and collective-action concepts used to interpret how the three domains interact. Our findings reveal a striking paradox. Although PAT-based cleaning is established in adjacent industries, strong cross-stakeholder convergence emerged around four enablers still missing, namely validated pilot projects, transparent sensor concepts to dispel black-box concerns, flexible validation standards, and targeted training to bridge automation and data-analytics gaps. The interviewees located the barriers not in technology but in coordination, validation, and governance across the value chain. Overall, the study suggests non-adoption as a possible coordination lock-in, without claiming a sector-wide mechanism. Thus, it provides a first multistakeholder analysis of barriers to sensor-based keg cleaning.