Snack foods comprise one of the strongest categories in the entire packaged food marketplace, with robust growth projected to continue for the next several years. Snack food manufacturers stand to benefit from a number of consumer trends, though there will be challenges as well.
Clean and Green Drive Sales
Three strong trends in the larger food world have a significant bearing on the snack food industry. One is the continued interest in high-protein and high-nutrition offerings, especially in single-serving sizes that can double as conveniently portable meals. A second is the continued rise of novel ingredients and preparations, inspired by chefs, Instagram influencers and the ongoing search for healthier, more sustainable foods. A third is the push toward “cleaner” foods, with consumers placing a high value on foods with short, comprehensible ingredient lists.
This creates a good news/bad news scenario for snack food producers. On the positive side, many consumers are increasingly open to premium, high-value snack foods with unfamiliar ingredients or combinations of ingredients. The negative is that they are less willing to tolerate additives and preservatives, especially in the form of polysyllabic chemicals, which makes it more difficult to maintain those novel ingredients at their peak levels of freshness and flavor.
Packaging, Not Preservatives
Flexible packaging can help compensate for the de-emphasis on conventional preservatives. Each of the ingredients in these gourmet snack foods can have specific requirements for maintaining their best shelf life. Some require oxygen to be shut out entirely, while others need carefully controlled levels of oxygen flow. The same holds true for the transmission of moisture in or out of packaging. Flexible packaging can provide meticulously engineered control of the environment, maximizing flavor and shelf life while still avoiding chemical additives.
The key is to identify which ingredients require a high-barrier film, which almost completely blocks the passage of oxygen and moisture, and which require a film that allows moderate or high transmission of oxygen and water vapor. Most snack foods, even innovative gourmet snack foods, rely on a relatively small handful of ingredient types with similar characteristics. For example, the following classes of ingredients require these storage conditions:
- Nuts, seeds and nut products. Nuts and seeds contain high levels of lipids that are susceptible to oxidative damage. They require high-barrier packaging and do well in modified atmospheres as low as 5 percent oxygen.
- Dried fruits and vegetables. Dried fruits, and dried vegetables such as vegan “jerky” made from mushrooms or kelp, also require high-barrier packaging Moisture absorbed from the surrounding environment can lead to molds and spoilage, while losing moisture could result in less than optimal texture.
- Fresh Produce. Fresh fruits and vegetables can be kept in a “snackable” condition as well, but they’re more challenging, partly because they’re living organisms that change the atmosphere they’re packaged in, and partly because shelf life is secondary to the customer’s perception of quality and freshness. For some fresh product items, atmospheres work well to slow browning and textural changes, while other fresh produce items require high OTR rates to maintain product freshness
- Chocolate and cocoa. Though chocolate and cocoa are high-fat ingredients, they’re relatively stable and less susceptible to oxidative damage. Milk chocolate, white chocolate and chocolates mixed with nuts are more perishable, because they contain ingredients that can become rancid more quickly than cocoa butter alone. They do best in packaging that minimizes their exposure to oxygen.
- Dry-cured sausage and meat products. Dry-cured sausages and other meat products containing fats are susceptible to rancidity caused by oxidative damage, and these products do best in high-barrier packaging. Vacuum sealing and modified atmospheres are helpful.
- Jerky and Dried Meats. Jerky is low in fat and resistant to rancidity, but its durability is founded on its low moisture content. It’s susceptible to spoilage if moisture is trapped in the package or if atmospheric moisture can penetrate the packaging, so it requires a high-barrier film. Loss of quality through odor absorption is also possible and should be factored into the package’s engineering.
- Meat-based protein snack bars. These are functionally equivalent to jerky made from ground meats and can be packaged in much the same way as conventional jerky.
Coping with Combinations
Choosing the right packaging and the right atmosphere for your snack food (when applicable) becomes more complicated when your snack contains multiple ingredients with oxygen or moisture requirements that don’t coincide neatly. Trail mixes and snack bars are obvious examples, combining nuts, dried fruits, chocolate, grains and potentially even nuggets of jerky or other high-protein add-ins.
A good general rule is to work from the needs of your most perishable ingredient, or the ingredient most susceptible to a consumer-perceived loss of flavor or texture.
There’s Serious Science Involved
Calculating the correct barrier properties for your packaging isn’t a simple back-of-the-napkin exercise. It starts with understanding the required oxygen and moisture levels of your ingredients, and, in the case of a snack food with mixed ingredients, how to optimally prioritize the various requirements. From there, though, it’s also necessary to understand how to achieve and maintain those levels by providing the appropriate laminated / COEX substrates.
Oxygen transmission rates are expressed in cubic centimeters of oxygen that can pass through a given area of film–either a square meter or 100 inches squared–in a 24-hour period. The abbreviation is cc/m2/24hr or cc/100 in2/24hr, depending on the area measurement used.
Oxygen isn’t the only gas that needs to be accounted for. Many foods preserve their freshness and quality best in modified atmosphere packaging, which pairs suitable films with a custom mixture of inert gases. These gases, most often nitrogen and carbon dioxide, minimize spoilage by replacing most or all of the oxygen within the package. MAP packaging requires both a gas supplier capable of furnishing an exactly appropriate mixture for your specific product, and a packaging supplier capable of creating a suitable film to contain it.
The atmosphere and chosen packaging work together to provide the maximum in product life, because transmission rates of these gases can differ. CO2 has a higher transmission rate than oxygen, for example, and over time your packaging can lose enough gas to look flaccid and deflated. The barrier films chosen must also take water vapor transmission into account. The water vapor transmission rate is measured as the weight of water in grams that can pass through 1 m2 or 100 in2 of a film within the same period.
To complicate things further, those measurements are taken under different conditions. Oxygen transfer rates are typically sampled at a temperature of 23°C or 73°F, and at 0 percent relative humidity. Water vapor transfer rates are measured at 38°C or about 100°F, and at 98 percent relative humidity. In the real world, however, your products will be sold and stored in environments that will seldom correspond to either condition.
Get the Help You Need
Balancing these considerations effectively requires a high level of experience and expertise with packaging methods and materials. Contact Flair Packaging today for more details about how our dedicated team of experts can help you with every step, from the design of your packaging to implementation and process management.
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