More and more processors are experimenting with unique materials and designs for product packaging. Tanweer Alam and Aastha Bhardwaj focus on the variants of packaging materials that have been employed or that could be employed for proper packaging of bakery and snack foods products in this article.


Due to the continuous expansion of the bakery and snack food industry, new packaging solutions are always in demand. India’s bakery market at Rs. 49.5 billion tonnes makes it the third-largest market in the Asia Pacific after Japan and Australia. Globally, the bakery product is growing @ 4.5 -7 per cent annually with $410 billion. The bakery industry in India comprises of organized and unorganized sectors. Large, medium and small scale manufacturers constitute the organized sector producing breads as well as biscuits while the unorganized sector constitutes small bakery and household units which manufacture these products and deliver them without proper packaging. Major varieties of dried bakery products (< 6 % moisture content), include soft and hard biscuits, cookies, crackers etc, and the varieties of moist bakery products (> 12 % moisture content), include breads, buns, cakes, pastries, doughnuts, muffins etc. However, these products are highly hygroscopic and easily tend to lose their crispness and flavor. For example, the dried bakery products have low moisture content but high fat content. Also, they are easily breakable. Thus, it is essential to have them protected from physical, chemical, and microbiological spoilages.

Requirements for Packaging of Bakery and Snack Products

Snack and Bakery products typically require higher barriers to keep them fresh, coated poly or metalized materials are normally used. For some products that have high turnover rates or that are shelf-stable as-is, standard poly materials can be used to save cost. With so many different materials and thicknesses available, choosing the right one for a particular product can be confusing. Many new manufacturers follow the trend of the industry when choosing packaging for their products. For example, many potato chip companies use metalized materials for their bags, so if a similar product is being introduced, it may be wise to use the same type of material. Shelf-life testing and careful analysis of material data sheets is always strongly recommended before committing to a material that has not previously been used with a product.

More and more customers are experimenting with unique materials and designs for product packaging. Rice papers, cotton papers and various clear coated films are giving graphic artists expansive mediums to work with. These outer materials coupled with the multiple-barrier and sealing layers available are helping to create some of the most attractive packages the market has seen. Appropriate packaging material in order to maintain the keeping quality and desired shelf life of the bakery products is the need of the hour. Proper selection and optimizing of packaging are of major importance to food manufacturers too with respect to aspects such as economy, marketing, logistics, distribution, consumer demands, and the environmental impact of the packaging. This article focuses on the variants of packaging materials that have been employed or that could be employed for the proper packaging of bakery products.

The major ingredients in biscuits consist of wheat flour, fat and shortening, sugar, salt and other flavouring agents. Thus, they are very much susceptible to rancidity, moisture uptake (water vapour) and oxygen reactions. The presence of light has also been found to be detrimental to colours or cause oxidation of fats leading to rancidity producing undesirable off-flavours. On exposure to moist conditions and atmospheric oxygen, fats get oxidized, thus resulting in rancidity and decreased shelf-life. The chemical spoilage in bakery products can be prevented by adding antioxidants like butylated hydroxyanisole (BHA), and butylated hydroxy toluene (BHT), a-tocopherol, ascorbic acid, and certain gums. Nitrogen flushing in packaging may also be an alternative approach in delaying rancidity in low moisture bakery products, In addition to these, moulds are the most common type of spoilage organisms related to bakery products. Hence the suitable packaging material should be resistant to growth of yeasts or molds and also grease resistant. Moreover, the packaging material should have low oxygen permeability in order to prevent oxidation and rancidity of the fat.

Types of Packaging Materials for Biscuits and Breads

Traditionally, biscuits and breads were packed in waxed paper wrappers. However, their use was limited as they had limited barrier properties. Aluminium had also been used as a packaging material for bakery products owing to properties such as heat conductivity, durability and strength, lightness, decorative potential and sustainability.

Packaging for Biscuits

Biscuits are fed into packing machines in continuous stacks this is achieved through stacker which converts free-flowing biscuits into uniform. The oldest flexible film to be used was cellophane because of its excellent gas barrier properties and heat sealability. Moreover, the traditional packaging of biscuits also includes tin. MST, MSAT, coated cellophane (MXXT) offer excellent moisture barrier, heat sealability and gloss. Enfold Wrapping is the classic, traditional biscuit wrapper. A portion of biscuits standing on edge is roll – wrapped or fold wrapped into a heat sealable film. Type of packing material is used in biscuit industry are Primary packaging: the packaging material which comes directly contact with product known as primary packaging Laminate/Wrapper, Wax Paper and Bopp films. The longitudinal packet seal is sealed tightly in a fin seal style. The packet ends are folded neatly and heat-sealed. Due to the neat and tight surrounding of the film, this packet gives utmost mechanical protection and acceptable barrier properties for hard and semi -hard biscuits and many other cracker types. Enfold wrapping is considered the most effective in terms of presentation by many marketing specialists – not only due to neat and impeccable shape, but also due to its ability to clearly distinguish the product amongst the host of pillow pack items on the retail shelves. However, with the advent of other newer packaging materials and techniques with better properties, cellophane became less popular when it became too expensive. The major shortcomings in traditional packages include: easy contamination and spoilage, poor shelf-life, unsuitability to transport distantly and for export purposes. The gradual advancement in the packaging industries came up with the following packaging avenues for mold-free preservation of bakery products: And the Secondary Packaging: These packaging are required basically for transportation /warehouse storage /handling. Mostly these are cardboard boxes or CBB made of kraft papers or sometimes these are tins.

Packaging for Breads

One of the priorities of today’s bread-making industry is to find suitable packaging solutions to satisfy the peculiar requirements of bread, mostly appreciated by consumers for its crispy crust. The packaging material should allow for both rapid heat exchange with the environment and water vapour evaporation to prevent condensation inside the package. Perforated orientated polypropylene (OPP) films are currently the best materials available for satisfying the industry’s requirements.

The films with variable barrier effects to water evaporation. The OPP film with hole mean diameter = 0.54mm and density = 21.4 holes/cm2 played an interesting role in modulating moisture variations. Wrapping bread in this film enabled both crust crispness and crumb softness to be maintained during 48h of storage. Such performances cannot effectively be obtained by using alternative industrial bread packaging materials, such as paper bags etc.

Namkeen Packaging

Now a day’s namkeen is omnipresent around the globe. The safety and appeal of these products, choosing the most appropriate namkeen packaging is of great importance. Namkeen should be prepared hygienically and packed in moisture-free packaging to preserve the flavor, freshness and quality of products. In particular, variations in the moisture inside the namkeen during storage and their influence on changes in crumb softness effect the selection of packaging films. OPP films and multi-layer metalized film bag with different hole size characteristics are the common choices for its packaging. Because of the considerable differences in the hole size characteristics. The flexible and durable namkeen packaging pouches are able to provide convenience in storage and transportation. It also enhances the overall visibility of products on shelves. Namkeen pouches are stored with ease and more cost-effective than the rigid packaging methods. Creative packaging designs which are able to increase the point of sale transactions and contents packed within our namkeen packaging bags are protected from harmful bacteria and excess moist are another important consideration. Pouches contain the following films including are LLDPE, PPE, BOPP, PE, and MET. The formats of namkeen Packaging commonly used by Namkeen Industry are: Re-sealable zipper, Euro slot, Transparent window, Hanging hole, Tear notch. Degassing valve, Rigid packaging, etc.

Other packaging systems for Snack Foods and Bakery products

Rigid packages are formed into definite shapes from strong constructive materials so that they retain their shape when filled with product and are not deformed unless subjected to sufficient force to destroy or damage the total structure. Plain cardboard boxes are utilized by many manufactures to pack biscuits to differentiate its product from competitors. These normal paper boxes which are slightly thicker. After the primary packaging by flexible wrappers is done, display boxes are used to pack these primary packages and then these boxes are shrink-wrapped to facilitate the consumers to see-through the transparent film of the package, thus pertaining to the aesthetic appeal of the product. Tins or metallic boxes are still being used for the packaging of soft cookies as they are easily susceptible to deformation. Tube Packaging in the form of tin tubes or cylindrical structures of different heights are used for cookies and biscuits. Glass and ceramic containers also constitute rigid packaging but the limitation of using glass as a packaging material is its bulk and fragility.

Flexible packaging of bakery products (e.g. laminates, wrappers)

The flexible packaging market is estimated to be worth $351 billion by 2018, meaning that it is rapidly gaining market share from other sectors such as traditional rigid packaging. A package or a container made of flexible materials like paper, plastic, foil or any combination of these, when filled with desired contents, can readily change their overall shape is termed as a flexible package. Paper bags may be used for the packaging of breads and baguettes but these have been replaced by polybags by some artisan bakeries as it is eco-friendly. Paper bags could be plain or can have printed material on them. Common examples of flexible packaging are bags and pouches and are the majorly used variants for packing bakery products these days. Other variants include: forms of wrappers, pre-formed pouches or form-fill pouches. Along with, are provided zig-zag fissures to facilitate easy tearing of the material by consumers, contradictory to primitive packaging materials that had plain ends causing difficulty in opening. Zip Pouches are introduced as resealable pouches meant for products to be carried over to a distance or to be kept for a longer period. These pouches have zip integrated into the pouches so as to open and close it as per convenience, thus retaining the crispness of the product and preventing entry of water vapor inside. Materials such as LDPE, PP, polyester etc have also been employed for this purpose. Another type of wrapping termed as pillow pack wrapping is the standard wrapping style for smaller biscuit packs (snack packs/single-serve packs), serving as a primary package and containing one or more piles of biscuits. In addition, pillow pack wrapping is used for bigger packets with products standing on edge (slug wrapping) as well. These primary packages can then be overwrapped by a bigger carton for strength. The main advantage of pillow packs on edge is its flexibility with regard to the slug length. Additionally, the pillow packs typical fin seal style sealing is somewhat tighter than the enfold wrap. This disadvantage of pillow pack slug wrapping is its limited mechanical product protection due to its rather loose packing. Further, the presentation of products packed using the pillow pack style is considered by most to be less attractive than enfold packets. Another material, which is widely used is biaxially oriented polypropylene film commonly known as OPP. For less

Different variants of plastic films and their uses

demanding applications, OPP monofilm is used while for higher quality products, duplex OPP or OPP combinations (pearlised or metallised ) such as OPP/PE, OPP/PET etc. are used. Polyvinyl chloride (PVC) trays are employed for packing of cookies and cakes to prevent any damage for e.g. Britannia Good day choco chips are packed in PVC trays. A major market of biscuit packaging is covered by flexible laminates of composite structures. They have desirable moisture barrier and gas barrier properties, heat sealability as well as printability characteristics. The different variants of plastic films and their uses are tabulated in table 1.

 

Modified Atmosphere Packaging

Modified atmospheric packaging, in recent years, has geared up all the way, as one of the best preservation methods of bread and biscuits. It can be defined as “the enclosure of food products in a high gas barrier film in which the gaseous atmosphere has been altered to slow down the metabolic processes, in turn, extending the shelf life of the food products”.

Bread products are excellent candidates for modified atmosphere packaging (MAP) and the technology is used widely for such foodstuffs. Typical products that benefit from MAP are tortilla wraps, baguette, bagels, pita, naan bread and other types of bread. Because these products have a relatively low water content, the type of microbes that can cause spoilage are mainly moulds, as bacteria prefer more water. These moulds are aerobic, so excluding oxygen and using a high proportion of carbon dioxide – up to 100% – is a highly effective way of significantly increasing the shelf life of these bread products. A big advantage of using very high CO2 as the modified atmosphere is that it makes the packaging relatively easy to test for leaks. Leak detection systems for carbon dioxide are well developed and can be configured to work automatically during the packaging process.

Developments in polymer chemistry have led to the development of new polymeric barrier packaging films such as PVDC and EVOH which have excellent moisture and gas barrier properties. Moreover, these can be laminated to give films having higher barrier properties, strength and heat sealability property. Several other methods can be used to modify the atmosphere within the packaged products such as vacuum packaging, gas flushing and active packaging by incorporation of oxygen scavengers.

Active packaging

Active packaging is increasingly becoming popular that can prove to be an indispensable vehicle in the preservation of food items as it offers more for bread and bakery products, major active packaging systems such as moisture controllers, oxygen scavengers, ethanol emitters, antioxidants, flavor releasing/absorbing systems, antimicrobials, etc are quite relevant.

It has been well documented that the shelf life of the bread and other baked products can be increased by spraying ethanol onto the surface of the product prior to packaging. Franke et al. (2002) studied the effects of an ethanol-releasing sachet on the shelf life of prebaked buns. Without the ethanol sachet, the buns had a shelf life of 2–3 days, while upon the incorporation of the sachet into the packaging, the shelf life was extended to an appreciable level of 13 days. Furthermore, this incorporated amount of alcohol does not hinder the consumption of the buns. It is recommended to heat the buns prior to consumption as a result of which the ethanol is vaporized.

Incorporation of volatile antimicrobial substances from spices and herbs into packaging materials may provide alternative effective ways of prolonging the shelf life of bread without the use of chemical preservatives (Jideani and Vogt, 2015). Gutiérrez et al. (2011) demonstrated that cinnamon-based active packaging is a suitable alternative for conventional MAP for gluten-free bread based on both microbial and sensory criteria.

Thermoformed Plastic Trays

Thermoformed plastics are used for the packaging of bread and bakery products. These trays are made of polystyrene or PVC with multiple cavities/depressions for packing assorted biscuits, cookies, rolls, muffins, etc. They are usually closed with a snap-on lid or overwrapped or shrink-wrapped or sealed with a lidding material. These products can be kept neatly in these cavities thus appealing to the consumer. The use of active packaging with oxygen absorbent and antimicrobial properties for bakery products helps to significantly increase the shelf-life and maintain the original quality of the product.

PVDC coated nylon, polyester, LDPE, PP, ethylene vinyl alcohol, polystyrene are examples of flexible packaging material used with active sachet.

Modern Packaging Solutions for Bakery Products

Customers require fresh and frozen loaves, buns, flatbreads, and many more different types of bakery products. Modern Packaging offers custom packaging solutions for your bakery product. packaging needs, including Zipper slider, Micro-perforation, Frozen or fresh packaging consideration, Barrier protection (for oil, moisture, oxygen or aroma), 8 colour graphics for your custom packaging design, NEW High-speed wicketer packaging machine, Single-serve / Multi-packs / variety packs, Differentiating graphics, shelf-ready, Extended shelf-life technologies.

Conclusion

Bakery and snack food products include items of different packaging requirements, which are met by a range of plastic materials in the form of films, laminates and thermoformed trays. These materials provide adequate protection against moisture loss/gain, retain the taste and aroma, and are hygienic and safe for food contact. Other additional properties such as machinability, printability, and cost-effectiveness make them the ideal choice for a package.

Selected References

  1. Berenzon, S., and Saguy, I. S. (1998). Oxygen absorbers for extension of crackers shelf-life. LWT-Food Science and Technology. 31(1): 1-5.
  2. Franke, I., Wijma, E., and Bouma, K. (2002). Shelf-life extension of pre-baked buns by an active packaging ethanol emitter. Food Additives & Contaminants. 19(3): 314-322.
  3. Gutiérrez, L., Batlle, R., Andújar, S., Sánchez, C. and Nerín, C. (2011). Evaluation of antimicrobial active packaging to increase shelf life of gluten-free sliced bread. Packaging Technology Science. 24: 485-494.
  4. Guynot, M. E., Marin, S., Sanchis, V., and Ramos, A. J. (2003). Modified atmosphere packaging for the prevention of mold spoilage of bakery products with different pH and water activity levels. Journal of Food Protection, 66(10): 1864-1872.
  5. Janjarasskul, T., Tananuwong, K., Kongpensook, V., Tantratian, S., and Kokpol, S. (2016). Shelf-life extension of sponge cake by active packaging as an alternative to the direct addition of chemical preservatives. LWT-Food Science and Technology. 72: 166-174.
  6. Jideani, V. A and Vogt, K (2015): Antimicrobial Packaging for Extending the Shelf Life of Bread – A Review, Critical Reviews in Food Science and Nutrition. DOI: 10.1080/10408398. 2013.768198

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