Making ugly food beautiful: Consumer barriers to purchase and marketing options for Suboptimal Food at retail level-A systematic review

The commercialization of Suboptimal Food (SF) constitutes a promising lever to tackle food waste. SF describes products that are unreservedly consumable but which have an abnormal appearance, and/or are nearing or have already passed their expiration date. Consumers may show awareness on food waste, yet do not choose SF accordingly. The aim of this review is thus to support the commercialization of SF by answering two questions: 1. Which barriers prevent consumers from buying SF?; and 2. How can retailers address these barriers? A systematic literature review was conducted in online databases, using a fixed search term and 2004-2019 as timespan. Forty relevant consumer studies were found. Alphabet Theory was applied as a framework for the analysis of the barriers, while the four P's of marketing were used for the measures. The review confirmed a variety of attitude-related quality concerns, often stemming from ill-founded conclusions based on appearance or nearing expiration, leading to an expectation of price discounts. While educational measures conducted by retailers (as part of SF campaigns) might be helpful, their effects on purchase behavior has not yet been well confirmed. More evidence exists on the effectiveness of framing SF positively, e.g. with sustainability and Corporate Social Responsibility messages or by highlighting the products 'naturalness'. Contextual changes are identified to be especially effective for supporting SF. In particular, increasing the availability of SF and enhancing the attractiveness of its presentation appears crucial. In future research, more store-tests are needed as well as investigations along the entire value chain.