Product quality biochemical degradation

Typical attributes for evaluating food quality are safety, shelf life, color, taste, flavor, texture, health, and convenience. The level of a quality attribute is determined by levels of physical, microbial, physiological, chemical, and biochemical food processes, product composition, and applied technological conditions. For example, a combination of enzyme-degrading colorants, compositions and concentrations of pigments, and food structure properties contribute to a certain color level perceived by consumers. Depending on the match of expectation and experience, certain attributes will or will not be perceived as quality. ... 

For all analytical testing, standard substances are required as reference material. These standards exhibit defined quality, and serve for all types of identity, purity, degradation product and potency assays as reference quantity. In QC, reference and working standards are used. Reference standards are highly purified and extensively characterized by all appropriate physico-chemical, biochemical and immunochemical methods. Working standards are used in daily practice, and are calibrated against reference standard for routine use. 

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