Protein Denaturation Exam Questions Solved Correctly Latest Update 2025

Protein Denaturation Exam Questions Solved Correctly Latest Update 2025 Denaturation - Answers process causing changes in protein structure without breaking the covalent peptide bonds in the polypeptide backbone Denaturation occurs whereby - Answers protein unfolds and changes shape but amino acid sequence remains Which protein structure does it not cause changes to - Answers primary Undesirable factor of denaturation - Answers loss of biological activity Desirable factor of denaturation - Answers affects physical and chemical properties for food processing like improved digestibility, foams, emulsifiers Effects of denaturation include - Answers 1. decreased solubility 2. water holding capacity 3. viscosity 4. critilisabillity 5. reactivity of peptide bond 6. loss of protein biological activity 7. improves protein digestibility What occurs due to hydrophobic groups exposure as protein unfolds? - Answers aggregation due to exposed side chains interacting with adjacent denatured protein the precipitation causing decreased solubility How does water holding capacity operate? - Answers increases or decreases depending on a system e.g.) denaturation of milk causes it to increase How does denaturation affect viscosity? - Answers increases it - increased volume and hydrodynamic radius= more volume and continuous movement of proteins - increased hydration as internal polar amino acids that interact with water are exposed What does denaturation cause to crystalisability? - Answers decreases it as disorder increases What conditions needed for reversible denaturation? - Answers mild e.g.) pH change, low urea, mild heat and rapid cooling Irreversible denaturation causes - Answers - loss of solubility - change in R group activity - drastic unfolding - difficult reversal Denaturing agents are either - Answers - physical e.g.) temp - cold/hot, pressure, mechanical shearing - chemical e.g.) pH, organic solvents, reducing agents Most common denaturation agent - Answers heat Rate of denaturing depends on - Answers temperature Denaturation Q10 - Answers measures rate of temperature increase x2-3 every 10 degree increase, effect of rising temperature 10 degrees on the rate of the chemical reaction What does a high Q10 mean? - Answers occurs over a narrow temperature range (2-3 degrees) What does heat do to bonds? - Answers destabilizes How does heat denaturation contribute to food processing? - Answers - improves/reduces sensory properties, protein digestibility - used in food analysis What pressure does high pressure processing occur at - Answers ~ 200- 600 mPa Proteins denatured by cold temperatures - Answers - glycine, storage protein in soybeans, aggregates and precipitates at 2 degrees - casein destabilisation as pH decreases and calcium increases Protein molecules are absorbed at interfaces of - Answers - water/air = foams