Page 262 - Natural Antioxidants, Applications in Foods of Animal Origin

Methods and Their Applications for Measuring 241
VetBooks.ir

Colorimetric Data 80% Lean Ground Beef
HOX MAPackaged , n= 20

T=O T+3 T+6
Days Stored in 38°F (3°C) Cooler

• Control • Anti ox # 1 :;: Anti ox #2
FIGURE 6.28 Colorimetry data (C*, Chroma) shows the addition of an antioxidant
improves the stability of raw meat pigments during storage. Negative oxidation reduction
potentials relates to higher color stability.

The ORP method for determining the oxidative status of meat products
is precise to within 5%; however, the following factors can reduce precision
and repeatability:

1. Temperature and ionic strength
2. Concentration of myoglobin (i.e., heme-iron) in the meat sample
3. Presence of oxygen in the homogenate
4. Time for potentiometer to reach a steady state

6.2.7 HEADSPACE ANALYSIS OF VOLATILE LIPID OXIDATION
PRODUCTS (GCMS)

TBARS method for quantifying secondary oxidation products in value-
added meats has stood the test of time, the need for faster turn-around, sensi-
tivity, and precision has become a bigger. GCMS headspace advantages
include reduced sample preparation time, increased sensitivity (LOQ), and
reduced analytical time. The GCMS method is gaining wider acceptance in
research and industry. Coupling the components of GC and MS allows for
the identification and quantification of a wide range of secondary oxidation
products in a meat sample.