In the last few decades blister packaging has been widely used for packaging of food products. The use of pre-formed plastic containers helps in portion control and protection of several foods with preservation of their freshness and safety.
What is Blister Packaging?
Blister packs also known as clamshell packaging, are made of pre-formed plastic and lidding seal attached to a cardboard base. The plastic forms little cups or “blisters” that contain the product like candies, nuts and bolts, or even food. The final piece, the lidding Seal which is in plastic or foil form, opens up to show the product.
Blister packaging can be traced back to the 1950s where the candy companies adapted the format for the selling of gums and chocolates. It was evident that the packaging ensured visibility of the products within the packaging as well as keeping them hygienically sealed and secure. Others industries followed and they started to use blister packs for packaging a variety of items ranging from tools and hardware to easily available drugs without prescription.
Over the past few years, the use of blister packaging food products has grown rapidly due to the flexibility, practicality and reduced cost involved in the manufacturing of this type of packaging. From fruits, nuts, and other dry produce to sandwiches, blister packs maintain the integrity of food and its portions. This makes it possible for the shoppers to view the contents with ease as a result of the high level of transparency.
Advantages of Blister Packs on Foods
Blister packs offer significant advantages when used for food packaging:Blister packs offer significant advantages when used for food packaging:
Portion Control
Another advantage of the blister pack is that the pre-formed compartments give measured single doses. This assists consumers to moderate portion size and avoiding taking more than the required amount of food. Whether it be catering for snack items such as nuts, candies, dried fruits or crackers to the main meals such as sandwiches or salads, blister packs do away with the element of guess work and portion control.
Freshness
This is because the lidding foil or plastic forms a lock to prevent compromise of the food to external factors that may lead to its deterioration. By sealing off air, blister packs help encapsulate tastes and maintain structure for a longer time. The packaging also helps prevent damages, contaminations, and even the impact of light exposure to the contents. The remaining portions of the pack also retain the same freshness even after the pack has been opened.
Easy to See Contents
The blisters are transparent plastic ones; therefore, the contents of the blister packaging are clearly visible. This means that consumers can easily know the available products in the market and what to look out for when it comes to quality. Products such as nuts and dried fruits cannot be selected or ‘picked’ since the pack has to be bought in its entirety.
Tamper Evidence
Typical for all sorts of well sealed packaging materials, the blister packs offer clear indications of tampering or product damage. Lidding that has been punctured or destroyed is evidently going to signal consumers against purchasing. The full opening of the contents also enables the users to check for things like, damaged crackers, or any other items that may have been crushed in the compartments.
Compact and Lightweight
In this way, compared to other forms of packaging that may require excessive packaging material, blister packs make products neat, thin, and light. It also contributes to cutting transportation expenses for sellers, and also, items become more convenient for consumers to move around, store and even use portably.
Resealable
Most blister pack products have resealable interlocking backing that enable the packaging to be closed again after the initial opening. This assists in protecting the parts that are not used during a particular time of snacking. Other products that can benefit from resealable blister packs are those that are used repeatedly such as hardware or medication products.
Sustainable
Since plastic remains to pose an issue in the environment, the packaging formats like the blister packs will be sensible offerings that reduce on material. The acts of forming, sealing and printing on to the plastic obviates the need for boxes, bags or wraps. Reduced amount of material used and increased product exposure lead to less clutter in the end.
Stackable and Displayable
The compact and thin nature of blister packs also enables them to be arranged in a manner that is compact and easily stored on shelves and display stands. This assists retailers get the most out of the available selling area. These are also effectively conveyed through the see-through presentation with ‘try me’ visibility, thereby grabbing the attention of consumers.
Blister Packaging Food Applications
Technological improvements in the plastic thermoforming and overall packaging manufacturing have made the blister packaging more accessible to even more food types. Packagers are not only in snacks but also ready-to-eat meals, fruits and vegetables, breads, etc. Popular blister pack food items include:Popular blister pack food items include:
- Nuts and seeds, and snacks and trail mixes
- Fruits, vegetables in dried form and jerky
- Snacks such as crackers, granola bar, energy bars
- Sandwiches, salads, fresh fruits
- Sandwiches, cookies, muffins, doughnuts
- Cheese, sausage, and deli meats
- Sweets, mints, gums, and choco bars
- Cereals, oat meal packets, dried soups
Microwave and oven-safe blister packs also enable the consumers to warm the goods in case of necessity.
MAP is also distinguished in blisters used for specific products such as sandwiches and fruits and vegetables. This makes it possible for packagers to scrub all the air within it and replace it with set proportions of oxygen, carbon dioxide, and nitrogen. This in turn reduces rate of ripening and rotting that assist in increasing shelf life significantly.
Blister Pack Production
Producing blister packs involves three key components:Producing blister packs involves three key components:
- Plastic thermoforming to form blisters
- Seal application
- Product insertion and sealing
Thermoforming begins with a roll or sheet of the material that can be PVC, which is heated to the point where it becomes flexible. The softened plastic is then vacuumed formed over specific molds to create the various blister shapes. Machines in the process give accurate time, pressure, and temperature to form blisters of a specific size and depth as required by the product.
Lidding foil or plastic is applied to the formed blisters through heat sealing or sonic welding, which binds the materials together without the use of adhesives. This forms a barrier that is tight and airtight around every blister compartment.
Food items are then packaged in blisters through automatic or manual methods before completing the sealing process. Certain machines include indexing conveyors that stop blister forms exactly on pneumatic plungers for quick insertion of the products depending on their weight or size. These fully automated systems have the capability of packaging hundreds of blister packs every sixty seconds.
Other equipment uses manual filling where operators gently place the products into blisters. Portion control may involve counting, weighing or even volumetrically portioning the food items to be served. Manual filling is useful when packing products with unusual shapes or which can easily be damaged as automated equipment cannot handle such products well.
Blister Package Sustainability
With consumers and regulatory authorities paying more attention towards the sustainability of packaging materials, blister packs are also being made more environmentally friendly. Replacing PVC plastic packaging with recyclable PET plastic is a good development. When forming blisters, thinner films are also employed, further decreasing the amount of plastic used.
When it comes to packaging, blister packaging takes less material than boxes, bags, jars, cans, or wraps. The proportion of plastic to product is as low as 10 percent, which is significantly lower than most packaging materials. This maximizes efficiency.
As the process of lightweighting and slimming blister materials has been defined, this process has advantages to sustainability in two aspects. First, it reduces production impacts that are associated with less energy and water usage and also fewer emissions compared to the rigid plastic tubs or thick material formats. Secondly, reducing the volume of plastic used per pack decreases the general amount of waste. This also reduces landfilling since the materials used in the product are releasable for recycling.
Most producers today employ blister materials that incorporate post-consumer recycled content or bio-based materials derived from renewable resources. Further advancements of compostable seal films will offer more opportunities to enhance the end-of-life footprint.
Blister pack foods in the future
Continuous advancements made on blister packaging that would target shelf life, product visibility, ease of opening, and eco-friendly material will increase the adoption of food products.
Some examples include antimicrobial addition into films that fights off bacteria and molds to enhance the shelf life of the food. Laser-perforated lidding foils assist to regulate the rate of oxygen permeability to allow slow respiration of sealed commodities. Such shelf life extending technologies give producers confidence with blister packaging goods that were previously limited to rigid packages and refrigerated supply chains.
Recent developments in in-line printing solutions not only enable packagers to modify graphics, but also to include tracking features such as barcodes and QR codes, NFC tags for connected consumer experience. A clear example of interactive retail media is through augmented reality and video packaging that offer virtual experiences. These features make the consumer focus on the product while at the same time highlighting essential product details.
These features include easy open and reclosable backs such as zippered and gusseted backings to protect parts not in use. Some of the sealing films used for the packs are luminescent or even have color changing abilities that show that the packs have been tampered with. Some of these features go on to cement consumer trust in blister packaged foods.
As methodologies continue to be developed for enhancing the recyclability, the use of post-consumer recycled material, and reducing material content and material protection methods, blister packaging will naturally increase as the most suitable format for an increasingly greater number of foods. In a world where most products are packed in difficult to recycle material and popular frivolous packaging, blister packs are ideal for presentation, practical, sustainable and performant.