Food Analysis Flashcards
Define Beer’s law.
Concentration and absorbance are proportional in spectroscopy
What is ELISA used for?
Detection of aflatoxin-to detect and quantify
What is the iodine value?
Number of centigrams of iodine absorbed by 1 gram of fat
What does p mean in pH?
-log
What is the gel most common used for protein analysis?
PAGE-polyacrylamide gel electrphoresis
What is the amount of energy to raise the temperature of 1 gram of water from 14.5 C to 15.5 C?
1 Calorie
What is phenolphthalein use for?
pH indicator, acid=colorless, base=red violet
What is Ohm’s Law and what is Power Equation?
V=IR and P=VI or I x I x R
What does Reichert-Meissert Number measure?
Primary butyric acid also caproic acid.
Name the most common functional property of phospholipids in food systems.
Emulsification
What are the two underlying principals of the Babcock test?
To dissolve fat from solids-non fat (SNF). To separate fat from SNF by centrifugal force.
The Delvo test is a commonly used rapid method for detection of antibiotic residue in milk. What organism is used in this test?
Bacillus Stearothermophilus
What are the Delvo and Charm tests used for?
Testing for the presence of antibiotics in milk.
Full name of WVTR?
Water vapor transmission rate
Isotherm water activity chart, x and y axis?
X: Aw, y: moisture.
Phases of colloidal dispersion?
Continuos phase or dispersion medium and dispersed phase or internal
Colligative properties of water?
Freezing point, boiling point, vapor pressure, osmotic pressure. Properties that depend on the number of solute molecules in water.
Define triple point?
Pressure-Tº at which substance is at solid, liquid and vapour phase at same time. For water is 611.73 Pa and 273.16 K.
What does Kjeldahl and how does it quantify proteins?
Measures nitrogen content
Michaelis menten equation?
Used for many enzyme kinetic, relates the velocity of a reaction with the concentration of substrate.
Henderson- Hasselbach equation?
pH = pKa + log[dissasociated salt]/log[associated salt]
What is pH?
The negative log of the concentration of hydrogen ion in solution.
Two isotopes used for food irradiation?
Co60 and Cs137
Test to detect carcinogenic antigen?
AMES test
NMR is often used as the technique to characterize the linkage types.
False, should be methylation analysis
