Solute-polymer-water interactions and their manifestations.
This paper reviews recent work on the interactions among solutes, polymers, and water in model food systems. Four possible combinations of ionic or non-ionic solutes and polymers are discussed in terms of their water sorption behavior. Comparisons between experimental values and values calculated by a mass balance equation are made. The salt-protein, sucrose-starch, and salt-starch combinations sorbed less water than that predicted by calculated sorption values. This was attributed to the inability of the interacted solutes to sorb their full complement of water. On the other hand, the sucrose-protein combination exhibited an increase in the amount of water sorbed over that calculated by the mass balance equation. This was attributed to the increased hydration of the protein component, due to an effect of the sucrose. One of the major factors involved in these solute-polymer interactions is the competition for water among the solutes and polymers. This competition, in turn, is greatly influenced by the "state" of the water associated with these components. Lastly, examples of how biological, chemical, and physico-chemical phenomena in foods are affected by these factors are also given. The phenomena discussed include mold germination, the Maillard reaction, ascorbic acid oxidation, protein functionality, starch gelatinization and retrogradation, and the complication of the order of mixing.
Chinachoti
P
P
Department of Food Science, University of Massachusetts, Amherst 01003.
Schmidt
S J
SJ
D002241:Carbohydrates / Q000737:chemistry; D055598:Chemical Phenomena; D002627:Chemistry, Physical; D005502:Food; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000737:chemistry; D012492:Salts / Q000737:chemistry; D012996:Solutions; D013213:Starch / Q000737:chemistry; D014867:Water / Q000737:chemistry*
D002241:Carbohydrates; D011108:Polymers; D011506:Proteins; D012492:Salts; D012996:Solutions; D014867:Water; D013213:Starch