HTM 2700 Lecture Notes - Lecture 18: Lecithin, Bain-Marie, Georgian Lari

• School: University of Guelph
• Department: Hospitality and Tourism Management
• Course: HTM 2700
• Professor: Alison Crerar

Document Summary

Specific ph where the electrical charge on a protein is neutralized. The point where the amino acid (a protein molecule) no longer has an electrical charge. The like charges of the protein are no longer repelling each other. Protein molecules are attracted to each other & form hydrogen bonds with each other creating larger molecules. When proteins are no longer colloidally dispersed they precipitate out of colloidal dispersion. Sometimes this is something we want (e. g. making cheese) Proteins in food exist at a ph different from their iep. Therefore, they exist as stable colloidal dispersions. E. g. milk has a ph of 6. 5-6. 7, casein proteins in milk have an iep of 4. 6. Sometimes it is a (cid:494)culinary catastrophe(cid:495) (e. g. curdled soft custard: ph least stable at their iep, mechanical action beating of egg whites. = change from the naturally ordered configuration (shape) of a protein molecule to a more randomly structured molecule.