Page 254 - Natural Antioxidants, Applications in Foods of Animal Origin

Methods and Their Applications for Measuring 233
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Diffuse Reflectance Spectroscopy Colorimetry, 95% Lean Ground Beef
Minolta 3500d at T+l4 days at 36°F (2°C) - 38°F (3°C)

FIGURE 6.21(b) Colorimetry data show a shift in the concentration of brown metmyoglobin
(Mbg) during storage.

Generally, for raw ground meat products, development of oxidized or
rancid flavors lags behind degradation of raw meat pigments. Pairing colo-
rimetry with methods for measuring the level of secondary oxidation prod-
ucts (e.g., TBARS or gas chromatography mass spectroscopy (GCMS)
headspace) defines whether the meat needs to be discounted or discarded.
Although visual appearance and flavor are the main drivers for consumer
acceptance of value-added meat products, nutritional value and wholesome-
ness are becoming influential considerations. The inherent nutritional value
of meat products (low caloric content and high biological value proteins
and source of essential minerals and B vitamins) is known; however, some
conventional meat products are being reformulated to respond to consumer’s
interests. For example, nutritionists and physicians are advising that calories
derived from fat be reduced to 25–35%, with less than 10% of the calories
from saturated fats (SFA), the ω-6 to ω-3 fatty acids be reduced to improve the
thrombogenicity and atherogenicity indicies (abbreviated IT and AI, respec-
tively). Based on these guidelines (American Dietetic Association, 2007), the
demand for conventional value-added meats could be marginalized unless
addressed through product reformulation and placement (Fig. 6.22).
The objectives for reformulating value-added meats to improve the
following.

1. The ω-3 to ω-6 fatty acid ratios
2. IT and AI
3. Shelf-life stability

Sodium reduction in value-added meats is of considerable interest to
consumers and health professionals. However, the role of salt (NaCl) as an