key term - Modified atmosphere packaging

Definition

Modified atmosphere packaging (MAP) is a food preservation method that alters the composition of the internal atmosphere of a package to enhance the shelf life and quality of perishable products. By replacing the air inside the package with a specific mixture of gases, typically reduced oxygen and increased carbon dioxide, this technique helps to slow down spoilage processes, control microbial growth, and maintain the overall freshness of food items.

5 Must Know Facts For Your Next Test

1. MAP can significantly extend the shelf life of fresh fruits, vegetables, meat, and dairy products by reducing respiration rates and inhibiting spoilage organisms.
2. The specific gas composition used in MAP varies depending on the type of food being packaged; for instance, high carbon dioxide levels are effective for meats while nitrogen is often used for baked goods.
3. MAP can be combined with other preservation techniques like refrigeration or freezing to maximize shelf life and maintain product quality.
4. The success of MAP is highly dependent on the selection of appropriate packaging materials that have suitable barrier properties to control gas exchange.
5. While MAP enhances food preservation, it’s important to monitor the modified atmosphere over time to ensure that gas concentrations remain within optimal ranges for food safety and quality.

Review Questions

• How does modified atmosphere packaging influence the respiration rates of fresh produce?
  • Modified atmosphere packaging lowers the oxygen concentration inside the package while increasing carbon dioxide levels. This shift in gas composition slows down the respiration rates of fresh produce, effectively delaying ripening and spoilage. By reducing respiration, the fruits and vegetables maintain their freshness for a longer period, leading to reduced waste and better quality for consumers.
• Discuss the role of permeability in selecting packaging materials for modified atmosphere packaging.
  • Permeability is a critical factor when selecting packaging materials for modified atmosphere packaging since it determines how gases like oxygen and carbon dioxide interact with the food product. Packaging materials must provide an adequate barrier to prevent unwanted gas exchange that could disrupt the desired atmospheric conditions within the package. If the material is too permeable, it could allow oxygen in, which would negate the benefits of MAP by promoting spoilage processes and reducing shelf life.
• Evaluate the effectiveness of combining modified atmosphere packaging with refrigeration in extending the shelf life of perishable foods.
  • Combining modified atmosphere packaging with refrigeration creates a synergistic effect that greatly enhances the shelf life of perishable foods. While MAP reduces respiration rates and inhibits spoilage organisms through gas composition manipulation, refrigeration slows down biochemical reactions and microbial growth further. This dual approach not only helps maintain product quality over extended periods but also ensures safety by minimizing potential pathogen growth, making it an effective strategy in food preservation.

Related terms

Shelf-life: The length of time that food remains safe to eat and maintains its desired sensory, chemical, physical, and microbiological characteristics.

Gaseous environment: The specific combination of gases present in a packaging environment, which can influence chemical reactions and microbial activity in food.

Permeability:

The ability of packaging materials to allow gases and moisture to pass through them, impacting the effectiveness of modified atmosphere packaging.