Chickpea protein isolates obtained by wet extraction as emulsifying agents.
BACKGROUND
Wet extraction of protein from defatted chickpea (variety Thiva (T), Greece) flour, at alkaline or slightly acidic pH, followed by isoelectric precipitation (pI) or ultrafiltration (UF) to recover the protein, was employed to obtain a number of chickpea protein isolates, enriched either in protein constituents belonging to the globulin (TpI, TUF, TUFG) or to the albumin fraction (TUFA).


RESULTS
The interfacial activity and film-forming ability of the isolate protein constituents as well as their emulsifying properties were evaluated. The method applied for chickpea protein isolate preparation influenced to an appreciable extent their composition, adsorption behaviour to oil-water interfaces and emulsion formation and stabilization characteristics, especially with respect to oil droplet flocculation and coalescence. The isolates also differed in their ability to stabilize emulsions subjected to thermal processing or following storage under freezing conditions. The results are discussed in terms of compositional and, possibly, structural differences existing between the protein constituents of the chickpea isolates that may influence their functional behaviour in emulsion systems.


CONCLUSIONS
The method applied for isolate preparation influenced to an appreciable extent the ability of proteins to adsorb to the oil-water interface and stabilize emulsions during long-time ageing or following heat treatment or freezing.
Papalamprou
Evdoxia M
EM
Laboratory of Food Chemistry and Technology, School of Chemistry, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
Doxastakis
Georgios I
GI
Kiosseoglou
Vassilios
V
D000327:Adsorption; D000418:Albumins / Q000737:chemistry; D002623:Chemistry Techniques, Analytical / Q000379:methods; D029863:Cicer / Q000737:chemistry*; D045703:Emulsifying Agents; D004655:Emulsions; D005916:Globulins / Q000737:chemistry; D009821:Oils; D010936:Plant Extracts / Q000737:chemistry*; D011506:Proteins / Q000302:isolation & purification*; D012639:Seeds / Q000737:chemistry*; D012995:Solubility; D013696:Temperature
D000418:Albumins; D045703:Emulsifying Agents; D004655:Emulsions; D005916:Globulins; D009821:Oils; D010936:Plant Extracts; D011506:Proteins