It is generally accepted that the quality of perishable products depends on three factors: the product, the user and the market situation. It is therefore difficult to define what quality is and how to control it. Decomposition of the effects of these factors on quality leads to a distinction between the assigned quality and the acceptability of a product. Assigned quality is the quality notion a consumer has of a product, and results from evaluating that product with respect to the consumer's specific criteria. Acceptability defines whether the consumer in a particular situation is willing to buy a particular product, and is the result of relating the product's assigned quality to other products and to extrinsic factors such as the price. Product and consumer research focus on assigned quality, whereas market research focuses on product acceptability. Changes in assigned quality can be simulated with quality change models that consist of separate models for the quality assignment, for the product behaviour and for the product environment.
Sloof, M., Tijskens, L. M. M., & Wilkinson, E. C. (1996). Concepts for modelling the quality of perishable products. Trends in Food Science and Technology, 7(5), 165-171. https://doi.org/10.1016/0924-2244(96)81257-X