Recent Advances in Food Process Engineering

Alternative protein manufacture has moved from conceptual advocacy to an engineering discipline in which ingredient fractionation, thermomechanical structuring, recombinant protein expression and mammalian cell culture are being developed as parallel routes to foods that displace conventional animal products. This critical narrative review examines the engineering evidence base across four platforms that are usually treated separately: plant protein extraction and fractionation, high-moisture extrusion and related shear-structuring technologies, precision fermentation of recombinant food proteins, and cultivated meat. Literature was identified through structured searching of open scholarly indexes and registries, supplemented by backward and forward citation tracking and by examination of authoritative institutional documents, with critical appraisal directed at methodological transparency, replication, scale relevance and the alignment between reported measurements and the claims they are used to support. Four cross-cutting problems emerge. First, ingredient purity is treated as a proxy for functionality even though comparative fractionation studies show that less-refined concentrates can outperform isolates in structuring, so purification frequently imposes environmental and economic costs without commensurate technical return. Second, mechanistic accounts of fibre formation during high-moisture extrusion remain contested, and the diversity of non-standardised texture measurements prevents quantitative comparison between laboratories. Third, recombinant food proteins are widely described as identical to their animal-derived counterparts, whereas the available structural and functional characterisations record systematic deviations in post-translational modification, aggregation state and interfacial behaviour. Fourth, techno-economic and life-cycle assessments of cultivated meat diverge by orders of magnitude because they encode incompatible assumptions about cell density, medium cost, facility design and energy supply, and the recent appearance of empirical pilot-scale data has narrowed rather than resolved that disagreement. Confidence is strongest for descriptive process–structure relationships and weakest for projected cost, environmental performance and long-term nutritional adequacy. Progress will depend less on new platforms than on standardised measurement, transparent assumption reporting and independent replication at pilot scale.