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250 Natural Antioxidants: Applications in Foods of Animal Origin
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Colorimetry Frozen Restructured Beef Steaks
95% Cl for the Mean
26
22 I
24
ro
'iii
0 20
* ro
c 18
(;) 16
E
·g 14
0 I I I I I
u 12 I
10 I I

Minolta CR300 colorimeter C light source 8mm aperature

FIGURE 6.35 Colorimetry data (a*) complement GCMS and sensory data. Raw meat color
of frozen restructured steaks in non-barrier packaging decreases over time. The data suggest
when raw meat color is a critical consumer attribute, barrier packaging may be required.

6.3 MEASURING THE CONSEQUENCES OF LIPID OXIDATION

6.3.1 WATER HOLDING CAPACITY (WHC)

Consequences of lipid oxidation is not limited to flavor, aroma, and color,
WHC is also adversely affected (Figure 6.36). As WHC decreases during
frozen storage, meat products will lose moisture during cooking resulting in
dry, “tough,” and chewy steaks.
Studies (Lund et al., 2007) conducted by meat scientists have deter-
mined that myofibrillar proteins are susceptible to chemical modification
due to oxidation. It is myofibrillar protein oxidation that has been a factor
in observed loss of WHC in raw and cooked value-added meats. Our study
was designed to determine the effect of natural antioxidants on meat protein
oxidation in raw frozen restructured beef steaks during 90 days of frozen
(–10 °F, –23 °C) storage. After 30, 60, and 90 days of frozen storage the
restructured steaks were thawed at 38 °F (6 °C) overnight and evaluated for
raw meat color (oxidation of sarcoplasmic protein) and WHC (a measure of
myofibrillar protein function). The trend in the data shows WHC decreases