Modified Atmosphere Packaging for Baked Goods
The principal spoilage mechanisms for non-dairy bakery products are mould growth, staling, and moisture migration. Yeasts may cause a problem in certain filled or iced products. Since non-dairy bakery products are generally less than 0.96, bacterial growth is inhibited and rarely a problem. However, some species of bacteria may be able to grow in certain products and hence pose a potential food poisoning hazard.
The food industry, always pursuing techniques to enhance product shelf life and retain the intrinsic quality of goods, has used MAP for its myriad benefits, with the constant demands of consumers for fresher, safer, and more natural products—devoid of preservatives. It provides an extended shelf life and ensures that food remains flavorful, moist, and nutritionally intact, making it a vital tool in the industry’s arsenal against waste, return rates, and compromised quality.
The Science Behind MAP
Modified atmosphere packaging, commonly known as MAP, is a food preservation and presentation method. At its core, MAP involves altering or modifying the internal atmosphere of a package to better preserve and protect the food product within. This is accomplished by replacing the ambient air inside a package with a carefully selected mixture of gases, creating an environment that can dramatically slow down the natural degradation processes.
Every food item undergoes natural processes that can lead to spoilage, and the primary culprits behind this degradation are microorganisms, enzymatic reactions, and oxidation. MAP strategically modifies the internal environment of a food package by adjusting the concentrations of specific gases, making it less conducive for these spoilage agents to thrive.
The key gases typically involved in MAP are:
- Nitrogen (N2): An inert gas that doesn’t easily react with food components. It’s primarily used to displace oxygen, preventing oxidative spoilage and inhibiting the growth of aerobic bacteria and fungi.
- Carbon Dioxide (CO2): Effective against a broad spectrum of bacteria and fungi. CO2 permeates the cell membranes of microorganisms, disrupting their normal function and inhibiting growth.
- Oxygen (O2): Though often reduced or eliminated due to its role in oxidative spoilage, oxygen is sometimes used in specific concentrations to maintain the colour of certain meats or support the growth of aerobic bacteria, which can outcompete spoilage organisms in certain products.
Benefits of Using MAP for Baked Goods
Baked goods hold a place in the culinary world with their enticing aromas, delicate textures, and delightful flavours. As consumers increasingly seek fresh, flavorful, and lasting products, MAP for baked goods has many benefits.
Extending Shelf Life: MAP extends shelf life as microbial growth is restricted by carefully controlling the mixture of these gases inside a package. Mould growth is one of the primary spoilage concerns for baked goods. By optimizing the gas mixture, MAP can significantly delay the onset of moulds, ensuring the product remains safe for consumption for extended periods.
As mentioned, certain gases can directly inhibit the growth of spoilage organisms. Oxidative reactions are also minimized by reducing or eliminating oxygen, the oxidation of fats (leading to rancidity) and the browning of fruits and vegetables are curtailed. Some enzymatic reactions that degrade food can be slowed down in altered atmospheric conditions.
Preserving Flavor, Texture, and Freshness: Beyond shelf life, MAP plays a pivotal role in preserving the intrinsic quality of the food. By halting or slowing down degradation processes, the flavorful components of food, especially volatile compounds, remain intact longer. For many food items, texture is as vital as taste. MAP ensures products remain crisp or soft as intended. Certain nutrients, especially some vitamins, are sensitive to oxidation and microbial activity. By slowing these processes, MAP can help maintain the nutritional profile of food.
Flavours in baked goods can deteriorate or change over time, especially in the presence of oxygen. By reducing or eliminating oxygen, MAP ensures that the taste remains as close to the “just-baked” flavour as possible. By manipulating the internal environment, MAP ensures that the moisture content remains stable, preserving the intended texture of the baked item. The colours of certain baked products can fade or change due to oxidation or other reactions. With MAP, the visual appeal, which often influences consumer choice, remains vibrant and fresh-looking.
Reducing Waste and Product Returns: Extending the edible life of baked goods means less food is in the bin. This is good for the environment and economically beneficial for retailers and consumers. Products that go stale or spoil before their expected date often lead to unhappy customers and product returns.
With the extended freshness offered by MAP, the rate of product returns diminishes, leading to better customer satisfaction and reduced logistical hassles for businesses. Retailers can also maintain a more flexible inventory with longer shelf lives, reducing the pressure of fast turnovers and potentially reducing frequent restocking costs.
Specific Gases for Baked Goods
The careful selection of gases and their precise proportions in modified atmosphere packaging (MAP) helps enhance baked goods’ shelf life and quality. While the gases used in MAP for baked goods might be common across the food industry, the specific proportions and combinations are meticulously chosen based on the unique requirements of each baked product. The result is an optimal environment that maintains these delectable treats’ freshness, taste, and quality.
- Nitrogen (N2):
- Inert Nature: Nitrogen, an inert gas, doesn’t react with the components of baked goods. This makes it ideal for MAP as it ensures no unintended chemical reactions occur within the packaging.
- Displacement of Oxygen: Nitrogen’s primary role in MAP for baked goods is to displace oxygen. By flushing the package with nitrogen, the amount of oxygen, which can lead to spoilage and oxidation, is significantly reduced or eliminated.
- Preventing Staleness: By displacing oxygen, nitrogen helps prevent the staling of baked goods, ensuring they remain fresh for a more extended period.
- Carbon Dioxide (CO2):
- Microbial Inhibition: Carbon dioxide is excellent at inhibiting the growth of various spoilage organisms, including moulds and bacteria, which are common culprits in the spoilage of baked goods.
- Permeability: CO2 can permeate through certain packaging materials over time. Thus, the initial concentration might be higher than the desired equilibrium concentration to account for this loss.
- Balancing Act: While CO2 is beneficial, its concentration must be optimized. High levels can lead to package ballooning, while too little may not provide sufficient microbial protection.
- Oxygen (O2) and its Limited Role:
- Oxidative Reactions: Oxygen is often seen as a problematic gas in food packaging due to its role in promoting oxidative spoilage. Oxidation can lead to rancidity in fat-containing baked goods and colour changes in certain products.
- Selected Uses: In some instances, a controlled amount of oxygen might be included in the MAP mix, especially if the baked product contains compounds that can benefit from it, like maintaining the red colour in some meat-inclusive pastries.
- Mould Growth: Oxygen can support the growth of aerobic moulds, which is another reason its presence is often minimized or eliminated in MAP for baked goods.
- Optimal Gas Mixtures for Different Products:
- Bread: Often packed with a high proportion of nitrogen to displace oxygen, combined with a smaller amount of CO2 to inhibit mould growth.
- Cakes and Pastries with Cream Fillings: Might have a mix that’s slightly higher in CO2 due to the moisture content and susceptibility to certain spoilage organisms.
- Dry Baked Goods (e.g., Crackers): Primarily nitrogen to prevent staling and maintain crispness.
- Pies and Meat Pastries: The mixture might be more complex, balancing the needs of the baked crust with the fillings, which might have fats and meats requiring specific gas combinations to prevent spoilage and maintain colour.
Modified atmosphere packaging (MAP) is becoming more commonly used in baking. Its primary benefits include extended shelf life, preserved quality, and reduced food waste. These advantages translate to consistent product quality for consumers and fewer returns for retailers.
However, the full potential of MAP remains untapped. Ongoing research is essential to optimize gas mixtures for diverse products and to understand MAP’s long-term implications. As more bakeries adopt MAP, it’s set to become a standard, elevating expectations for baked goods’ shelf life and quality.
Stream Peak supplies Modified Atmosphere Packaging (MAP) films designed to preserve freshness and extend the shelf life of perishable products. This packaging solution is engineered to create an optimal gas composition within the package, tailored to the specific requirements.