NUTR 20500 Lecture Notes - Lecture 4: Hydrogen Bond, Electronegativity, Covalent Bond
31 Aug 2016
School
Department
Course
Professor
Document Summary
Very short range, much weaker than other forces; important in food because larger particles (like emulsion droplets) also exhibit these forces. Between a hydrogen atom (electronegative atom) and another neighboring electronegative atom. Stronger than van der waals but weaker than ionic or covalent. Important in food because of water and the innumerable molecules with oh groups are similar. Like dissolves like; if you have dissimilar pairs, you will need an aid to dissolution. The intensity with which water associates with various non-aqueous components . Where p= water vapor pressure over sample, p0= water vapor pressure over pure water. Or aw=erh/100 where erh= equilibrium relative humidity. The closer aw of a system is to one, the more the water in that system behaves like pure water. Pure water has different properties than water that is interacting with other molecules because of hydrogen bonding. Water activity is a better predictor of reactions than water content.
