Page 388 - Natural Antioxidants, Applications in Foods of Animal Origin

Control of Lipid Oxidation in Muscle Food 367
VetBooks.ir effect. Concentrations of 20–60% of CO are necessary for complete inhibi-

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tion of aerobic spoilage microorganism, but slight or no effect is observed
with CO values above 50–60% (Gill & Tan, 1980). In relation to CO,
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the shelf life is extended by adding CO at levels above 0.5% (Clark et al.,
1976). However, the effect of CO is variable on pure microbial cultures
as reported by Gee and Brown (1980). Numerous works have studied the
effect of concrete gas mixtures on the microbiology of MAP meat and on
the growth of particular microbial groups or relevant spoiling or pathogenic
species (McMillin, 2008). Viana et al. (2005) reported that counts of lactic
acid bacteria increased during storage in pork loin packed in oxygen-free
atmospheres, while they reached the lowest counts in 100% O atmosphere
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after 20 days of storage; the growth of Pseudomonas was limited in 100%
CO and 1% CO + 99% CO atmospheres, with the highest counts in 100%
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O . According these authors, pork treated with the 1% CO + 99% CO atmo-
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sphere received the greatest acceptance by the consumers.
Regarding the gas mixtures commonly used, the high O MAP can have
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25–90% O and 15–80% CO in the headspaces (Blakistone, 1999), being
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80% O + 20% CO the most used gas mixture (Eilert, 2005). In relation to
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color, the oxymyoglobin levels of minced meat were similar after four days
of storage in 20, 40, 60, and 80% O atmospheres, but in all the cases higher
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than in meat stored in air, although after seven days of storage the oxymyo-
globin content decreased with the O decrease. At the 10th day of storage,
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lipid oxidation slightly increased as the O percentage was higher (O’Grady
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et al., 2000). Luño et al. (1998) studied the effect of a low O atmosphere
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containing CO (24% O + 50% CO + 25% N + 1% CO) in comparison
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with a high O atmosphere containing CO (70% O + 20% CO + 9% N +
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1% CO) and with a high O atmosphere without CO (70% O + 20% CO +
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10% N ) on the psychrotrophic counts and color stability throughout storage
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of loin steaks and ground meat. Psychrotrophic counts were greatly reduced
by the low O atmosphere containing CO, while the bright-red color was
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more stable in both atmospheres containing CO, reaching 29 days of storage
without signs of oxidation, which was confirmed using sensory analysis.
9.5 ACTIVE PACKAGING
The function of food packaging has evolved from simple preserva-
tion methods to include such aspects as convenience, point of purchase
marketing, material reduction, safety, tamper-proofing, and environmental
issues (Han, 2014). Active packaging is a novel technology which is designed