India is one of the largest producers of commodities like foodgrains, sugar, fruits, vegetables and tea. Due to varied crop pattern, localized production of commodities, safe and hygienic storage, transportation and distribution and protection against wastage, hence packaging is of utmost importance. Huge losses have been observed in agriculture produce in India. Wastage varies from 5 to 35% depending on nature of crops.
Majority of wastage takes place in each of the above steps viz. storage, transportation and at retail market due to improper packaging. Bulk Packaging provides a solution for commodities weighing 10 to 50 Kg during handling, storage and transportation.
The present paper describes trends in Bulk Packaging for various commodities, suitability of Polypropylene (PP) Woven Sacks for packaging of foodgrains, sugar, tea, similarly for packaging and transport of vegetables and other horticulture produce PP leno bag is an effective packaging system. With changing packaging need, optimization of packaging role of Flexible Intermediate Bulk Container (FIBC) and its future has been highlighted as trend. PP Woven sacks are worldwide material of choice for bulk packaging of edible commodities for domestic use and exports.
Trends in Bulk Packaging:
PP Woven Sacks / FIBC, Jute, Paper bags/ box are most widely used packaging systems for Bulk Commodities. Cement, fertilizer and most of the chemicals are already packed woven sacks while Foodgrains and sugar use both woven sacks and jute bags. Plastics are the material of choice because of inherent advantages of functional performance and cost benefits. Relative merits with respect to functional requirement for bulk packaging using these three prime packaging materials are summarized in Table-1
| Functional Requirement for Bulk Packaging (Table-1) | |||
| Parameter | Jute |
Paper |
PP Woven Sacks |
| Seepage | Relatively High |
Low |
Low |
| Moisture Prevention | Nil |
Nil |
Excellent |
Contamination / Infestation |
Very High |
Nil |
Low to Moderate |
| Organoleptic deterioration | Very High |
Moderate |
Minimum |
| Aesthetics | Poor |
Good |
Good |
| Availability | Seasonal |
Limited |
Abundant and Easy |
| Cost | High |
High |
Low |
| Seam Strength | Strong |
Strong |
Low |
| Operational Convenience | Good but Abrasive |
Good |
Good |
| Stack Stability | Good |
Good |
Good |
| Drop Test Performance | Fair |
Poor |
Very Good |
| Microbial attack | Very High |
High |
Nil |
| Air borne pollution | Very High |
None |
None |
| Biodegradability | Yes |
Yes |
No |
| Energy Recovery | Low |
Low |
High |
| Reusability | Good |
Nil |
Good |
Production of PP Woven Sacks:
Polypropylene (PP) is used as the basic raw material and is fed to the hopper of extruder and melted to pass through a T- die in film form which is then slit into tapes, which are then oriented by stretching and wound in cheese winders. Tapes are then fed into circular / flat looms and woven into tubular or flat fabric respectively. These fabrics can then be laminated based on functional need of the packaging. Finally fabrics are cut into pieces as per bag specification with stitching in bottom and top as per requirement followed by printing.
Plastic Woven Sack Industry:
Globally woven sack production is 6.25 mln tpa. This industry is growing at 5.6% CAGR over last 5 years. India, one of the leading woven sack producer, consumes 0.7 mln tpa and is growing at 8.7% CAGR, much faster than world average.
Bulk Packaging of foodgrains, sugar, tea and fruits and vegetables are taken as case studies to establish suitability of PP Woven Sacks and leno over other material of choice.
PP Woven Sacks for foodgrain and sugar packaging:
Packaging and storage of foodgrains and sugar is a challenging job. Both are hygroscopic and thermally active. Ideal Packaging System for these commodities should have adequate mechanical properties and should sustain the quality on long-term storage as shown in fig. 1
Considering the packaging need both International and Indian standards are used. In India BIS standards have been formulated for plastic woven sacks for foodgrain (IS 14887:2000) and sugar (IS: 14968: 2001) Packaging.
Various studies and field trial have been conducted both in food storage godowns and laboratories to establish suitability of PP Woven Sacks for long-term storage of Foodgrains and sugar. The studies have been conducted from institute of repute like Indian Agricultural Research Institute (IARI), Indian Grain Storage Management and Research Institute (IGMRI), Industrial Toxicological Research Centre (ITRC), and Indian Council for Agricultural Research (ICAR) etc. Test and trial parameters were selected in view of most important parameters with respect to Foodgrains storage and packaging.
Outcome of these studies and trial compared to other conventional material of packaging can be summarized as under:
• PP Woven Sacks restrict moisture permeation and insect penetration.
• Lower temperature during storage hence lesser insect germination
• Better insecticide persistency to reduce its application and cost
• Odour of the stored commodity is not altered
• From Entomological aspects PP Woven Sacks are superior
• CFTRI certification of raw materials used for PP Woven Sacks from safety angle for food contact applications.
• ITRC has certified these bags suitable and meet all the physico-chemical and biological tests required for food grain storage.
• Food grains stored in PP Woven Sacks conform to ‘Prevention of food adulteration act and rules’ as per Delhi Test House report.
• Mechanical properties of PP Woven Sacks (tensile strength and stretchability) are superior
• Drop impact strength and slip tendencies of bags stacked are better and comparable respectively with stack height up to 35 layers.
All these studies clearly indicate PP Woven Sacks as an ideal bulk packaging solution for food grains and sugar.
PP Woven Sacks for Bulk Auction Tea Packaging:
India produces about 820 Million Kg of Tea every year. Out of this ~ 475 Mn Kg tea is auctioned through six auctioning centers. Auction tea is packed either in jute, paper or PP Woven Sacks. With changing packaging requirement, better protection of the tea and viability of packaging cost reduction, Tea Board of India, Calcutta Tea Traders Association (CTTA), Indian Tea Association (ITA), approached IIP for a packaging evaluation study. All the required parameters of tea packaging were evaluated which included mechanical properties of the bags, organoleptic properties of liquor and leaf, Chemical quality of the tea.
Comparative study indicates PP Woven Sacks as the most suitable material for packaging of auction tea as under:
• Shelf life evaluation on moisture content and organoleptic properties of tea stored in PP Woven Sacks also found to be better than in jute bags
• Chemical quality of tea stored in jute and PP Woven Sacks were comparable
• Mechanical properties of PP Woven Sacks have been found to be better than jute bags in all respect
• Transport worthiness and stackability found to be comparable to that of jute bags.
All the above test reports and findings indicate PP Woven Sacks as better and much cheaper option for bulk auction tea packaging.
Fruits and Vegetable Packaging: Leno bags the Ideal Choice:
India is the second largest producer of fruits and vegetables in the world. But our national loss of F and V is staggering as high as 35%. Lack of cold storages, PHM, improper packaging and abusive handling of farm produce are major reason of losses. Horticulture produces are sent to various Mandis by trucks without any packaging or mainly in wooden box, paper cartons, jute bags and crates.
Leno with following features over traditional materials is excellent fit for them.
• Excellent breathability, No rotting, sweating of vegetables.
o Increase the shelf life of contents.
o Lower wastage and spillage.
• No Fungal growth, hence hygienic
• Good aesthetics and visibility hence quality product
• Good strength of the bags
• Lighter in weight -more can be transported at lower cost.
• Does not impart Odour to packed contents.
• Insects and chemical resistant.
Coupled with cost advantages of leno over jute bags it has become world choice for fresh fruit and vegetable packaging. Export norms by some counties too specify use of leno as packaging material particularly for onion, potatoes etc.
FIBC as Future Bulk Packaging Solution:
Flexible Intermediate Bulk Containers (FIBC) is a relatively new entrant in bulk packaging concept in India. It has already gained huge success and being extensively used in all the developed countries as most inexpensive but effective storage, transportation and packaging solution for food grains, chemicals, pharmaceuticals, bakery products and as well as Industrial products. Capacities ranges from 500- Kg to 2000 Kg). The growing use of FIBC in different markets is partly caused by users changing their packaging solutions (eg. woven sacks, multi-wall paper bags, kraft octabins, metal bins and plastic RBC) to FIBC - in Europe this could have been a result of the EU Packaging Directives. Increased availability of specifically designed filling and discharging machines is also another reason for shift from conventional packaging to FIBC. Popularity and use of FIBC will continue to grow as handling becomes increasingly easier and cost savings are even more readily identifiable over other types of packaging. In our environmentally conscious world, FIBC offer an excellent alternative to the traditional packaging solutions as they can be reused as well as recycled and therefore minimize disposal problems.
Conclusion:
Bulk Packaging has to be strong, durable, light in weight, provide adequate protection with increased storage/ shelf life, easily handled, cost effective, reusable, recyclable and impact on environment should be minimum on holistic approach considering life cycle analysis of the packaging material.
Considering all above we can summarise PP woven sacks
FIBC and leno bags are ideal for Bulk Packaging.
(Author: Dr UK Saroop, Reliance Industries Ltd.)
References Courtesy:
• Studies on suitability of plastic woven sacks for foodgrain packaging (a) Engineering aspects (b) Entomological aspects by Indian Council of Agricultural Research- Sponsored by CPMA
• Suitability of PP/HDPE Bags for storage of Paddy in Commercial Godowns by Indian Grain Storage Management and Research Institute (IGMRI) – sponsored by CPMA
• Conformation to” The prevention of Food adulteration Act and Rules- 1955 (PFA), 2001 and fit for human consumption study by Delhi Test House – Sponsored by CPMA
• Report on suitability of PP woven sacks for packaging of Bulk Tea by IIP- Sponsored by CPMA
• Life Cycle Analysis of PP-HDPE Woven sacks vis-ŕ-vis Jute/Paper sacks in terms of Environmental studies.