Methodological Protocol - Digital Twin Implementations in Food Processing Unit Operations (PRISMA-2020 Systematic Review Protocol)

This document presents the methodological protocol for the systematic review titled “Digital Twin Implementations in Food Processing Unit Operations: Data Integration Maturity, Analytical Capability, and Readiness.” The protocol was developed according to the PRISMA 2020 guidelines and outlines the procedures for literature search, eligibility assessment using a PICO-derived PICOS framework, study screening, quality assessment using a four-criterion appraisal scale (0, 0.5, and 1; minimum threshold 3.0/4.0), data extraction, and synthesis. The review classifies digital twin maturity following Kritzinger et al. (digital model, digital shadow, and digital twin), analytical capability (descriptive, diagnostic, predictive, prescriptive, and autonomous), and modelling approaches (white-box, black-box, and hybrid). Statistical analyses include the Fisher–Freeman–Halton exact test, Kendall's tau-b, Cramér's V, and temporal robustness checks. The study aims to map digital twin readiness in food processing unit operations, identify implementation gaps, and establish future research directions.