ABSTRACT
The glass transition concept was advanced further by the development of state diagrams for foods. A state diagram is a stability map of different states and phases of a food as a function of water or solids content and temperature. Most probably, Levine and Slade [1] presented the first state diagram in the food science literature by illustrating glass line, freezing curve, and the intersection of these lines as T g ʹʹ by extrapolation of the extended freezing curve by maintaining similar curvature (Figure 24.1). The main advantage of drawing a map is to help in understanding the complex changes that occur when the solids content (or water content) and temperature of foods are changed. It also assists in identifying the stability of foods during storage as well as selecting suitable conditions in terms of temperature and moisture content for processing to achieve the desired product characteristics. This chapter provides the components of the state diagram by discussing macro- and micro-regions, and by explaining selected applications in determining food’s stability during processing and storage. Macro-region state diagram; 1, 2, 3, 4 indicate the degree of stability, 1: most stable and 4: least stable. (From Levine and Slade [<xref ref-type="bibr" rid="CH024_CIT00001">1</xref>].) https://s3-euw1-ap-pe-df-pch-content-public-u.s3.eu-west-1.amazonaws.com/9780429091483/664b9b5a-638a-4ec7-b69b-5d34889988bd/content/fig24_1_B.tif" xmlns:xlink="https://www.w3.org/1999/xlink"/>
