FDSC 305 Study Guide - Midterm Guide: Ammonium Sulfate, Food Browning, Epimerase And Racemase

• School: McGill University
• Department: Food Science
• Course: FDSC 305
• Professor: Benjamin Simpson

Document Summary

Both are isomerase enzymes that catalyze the reverse stereochemistry of biological molecules. Racemases act on compounds with one asymmetric center whereas epimerases act on compounds with more than one asymmetric center (epimers). Chlorophyllase eliminates the phytyl group from chlorophyll, turning it into the bright green water soluble pigment chlorophyllide. 4 ways to stop discoloration/destruction of chlorophyll - 1/v0 . how did you get to this using the km equation. Reduce contact with oxygen (to prevent oxidation- add liquid such as water or other without oxygen, add additives such as edta), reduce ph to decrease rate of enzymatic browning, avoiding high temperatures (freezing) Guiacol turns from colorless to brown after reacting with oxygen. Peroxidases converts hydrogen peroxide to water and oxygen. The concentration of this pigment is therefore related to peroxidase activity and can be measured by using a spectrophotometer. Measures we can take to stop green discoloration of chlorophyll. Avoid contact to air and light, avoid heating of chlorophyll, avoid.