| Introduction | | | | (starch), and other materials to give it wet |
| Packaging fresh fruits and vegetables is one of | | | | strength and printability. Most fiberboard contains |
| the more important steps in the long and | | | | some recycled fibers. Minimum amounts of |
| complicated journey from grower to consumer. | | | | recycled materials may be specified by law and |
| Bags, crates, hampers, baskets, cartons, bulk bins, | | | | the percentage is expected to increase in the |
| and palletized containers are convenient containers | | | | future. Tests have shown that cartons of fully |
| for handling, transporting, and marketing fresh | | | | recycled pulp have about 75 percent of the |
| produce. More than 1,500 different types of | | | | stacking strength of virgin fiber containers. The |
| packages are used for produce in the U.S. and the | | | | use of recycled fibers will inevitably lead to the |
| number continues to increase as the industry | | | | use of thicker walled containers. |
| introduces new packaging materials and concepts. | | | | Double-faced corrugated fiberboard is the |
| Although the industry generally agrees that | | | | predominant form used for produce containers. It |
| container standardization is one way to reduce | | | | is produced by sandwiching a layer of corrugated |
| cost, the trend in recent years has moved | | | | paperboard between an inner and outer liner |
| toward a wider range of package sizes to | | | | (facing) of paper-board. The inner and outer liner |
| accommodate the diverse needs of wholesalers, | | | | may be identical, or the outer layer may be |
| consumers, food service buyers, and processing | | | | preprinted or coated to better accept printing. |
| operations. | | | | The inner layer may be given a special coating to |
| Packing and packaging materials contribute a | | | | resist moisture. Heavy-duty shipping containers, |
| significant cost to the produce industry; therefore | | | | such as corrugated bulk bins that are required to |
| it is important that packers, shippers, buyers, and | | | | have high stacking strength, may have double- or |
| consumers have a clear understanding of the | | | | even triple-wall construction. Corrugated fiberboard |
| wide range of packaging options available. This | | | | manufacturers print box certificates on the |
| fact sheet describes some of the many types of | | | | bottom of containers to certify certain strength |
| packaging, including their functions, uses, and | | | | characteristics and limitations. There are two |
| limitations. Also included is a listing, by commodity, | | | | types of certification. |
| of the common produce containers standard to | | | | The first certifies the minimum combined weight |
| the industry. | | | | of both the inner and outer facings and that the |
| The Function of Packaging or Why package | | | | corrugated fiberboard material is of a minimum |
| Produce? | | | | bursting strength. The second certifies minimum |
| A significant percentage of produce buyer and | | | | edge crush test (ETC) strength. Edge crush |
| consumer complaints may be traced to container | | | | strength is a much better predictor of stacking |
| failure because of poor design or inappropriate | | | | strength than is bursting strength. For this reason, |
| selection and use. A properly designed produce | | | | users of corrugated fiberboard containers should |
| container should contain, protect, and identify the | | | | insist on ECT certification to compare the |
| produce, satisfying everyone from grower to | | | | stackability of various containers. Both certificates |
| consumer. | | | | give a maximum size limit for the container (sum |
| PACKAGING POINTS | | | | of length, width, and height) and the maximum |
| Recyclability/Biodegradability. | | | | gross weight of the contents. |
| A growing number of U.S. markets and many | | | | Both cold temperatures and high humidities reduce |
| export markets have waste disposal restrictions | | | | the strength of fiberboard containers. Unless the |
| for packaging materials. In the near future, almost | | | | container is specially treated, moisture absorbed |
| all produce packaging will be recyclable or | | | | from the surrounding air and the contents can |
| biodegradable, or both. Many of the largest buyers | | | | reduce the strength of the container by as much |
| of fresh produce are also those most concerned | | | | as 75 percent. New anti-moisture coatings (both |
| about environmental issues. | | | | wax and plastic) are now available to substantially |
| Variety. | | | | reduce the effects of moisture. |
| The trend is toward greater use of bulk packages | | | | Waxed fiberboard cartons (the wax is about 20 |
| for processors and wholesale buyers and smaller | | | | percent of fiber weight) are used for many |
| packages for consumers. There are now more | | | | produce items that must be either hydrocooled or |
| than 1,500 different sizes and styles of produce | | | | iced. The main objection to wax cartons is |
| packages. | | | | disposal after use- wax cartons cannot be |
| Sales Appeal.High quality graphics are increasingly | | | | recycled and are increasingly being refused at |
| being used to boost sales appeal. Multi-color | | | | landfills. Several states and municipalities have |
| printing, distinctive lettering, and logos are now | | | | recently taxed wax cartons or have instituted |
| common. | | | | rigid back haul regulations. Industry sources |
| Shelf Life. | | | | suggest that wax cartons will eventually be |
| Modern produce packaging can be custom | | | | replaced by plastic or, more likely, the use of ice |
| engineered for each commodity to extend shelf | | | | and hydrocooling will be replaced by highly |
| life and reduce waste. | | | | controlled forced-air cooling and rigid temperature |
| Containment | | | | and humidity maintenance on many commodities. |
| The container must enclose the produce in | | | | In many applications for corrugated fiberboard |
| convenient units for handling and distribution. The | | | | containers, the stacking strength of the container |
| produce should fit well inside the container, with | | | | is a minor consideration. For example, canned |
| little wasted space. Small produce items that are | | | | goods carry the majority of their own weight |
| spherical or oblong (such as potatoes, onions, and | | | | when stacked. Fresh produce usually cannot carry |
| apples) may be packaged efficiently utilizing a | | | | much of the vertical load without some damage. |
| variety of different package shapes and sizes. | | | | Therefore, one of the primarily desired |
| However, many produce items such as | | | | characteristics of corrugated fiberboard containers |
| asparagus, berries, or soft fruit may require | | | | is stacking strength to protect the produce from |
| containers specially designed for that item. | | | | crushing. Because of their geometry, most of the |
| packages of produce commonly handled by hand | | | | stacking strength of corrugated containers is |
| are usually limited to 50 pounds. Bulk packages | | | | carried by the corners. For this reason, hand holes |
| moved by fork lifts may weigh as much as 1,200 | | | | and ventilation slots should never be positioned |
| pounds. | | | | near the corners of produce containers and be |
| Protection | | | | limited to no more than 5 to 7 percent of the |
| The package must protect the produce from | | | | side area. |
| mechanical damage and poor environmental | | | | Interlocking the packages (cross stacking) is |
| conditions during handling and distribution. To | | | | universally practiced to stabilize pallets. Cross |
| produce buyers, torn, dented, or collapsed | | | | stacking places the corner of one produce |
| produce packages usually indicate lack of care in | | | | package at the middle of the one below it, thus |
| handling the contents. Produce containers must be | | | | reducing its stacking strength. To reduce the |
| sturdy enough to resist damage during packaging, | | | | possibility of collapse, the first several layers of |
| storage, and transportation to market. | | | | each pallet should be column stacked (one |
| Because almost all produce packages are | | | | package directly above the other). The upper |
| palletized, produce containers should have | | | | layers of packages may be cross stacked as |
| sufficient stacking strength to resist crushing in a | | | | usual with very little loss of pallet stability. |
| low temperature, high humidity environment. | | | | There are numerous styles of corrugated |
| Although the cost of packaging materials has | | | | fiberboard containers. The two most used in the |
| escalated sharply in recent years, poor quality, | | | | produce industry are the one piece, regular slotted |
| lightweight containers that are easily damaged by | | | | container (RSC) and the two piece, full telescoping |
| handling or moisture are no longer tolerated by | | | | container (FTC). The RSC is the most popular |
| packers or buyers. | | | | because it is simple and economical. |
| Produce destined for export markets requires | | | | However, the RSC has relatively low stacking |
| that containers to be extra sturdy. Air-freighted | | | | strength and therefore must be used with |
| produce may require special packing, package | | | | produce, such as potatoes, that can carry some |
| sizes, and insulation. Marketers who export fresh | | | | of the stacking load. The FTC, actually one |
| produce should consult with freight companies | | | | container inside another, is used when greater |
| about any special packaging requirements. | | | | stack- ing strength and resistance to bulging is |
| Additionally, the USDA and various state export | | | | required. A third type of container is the Bliss box, |
| agencies may be able to provide specific | | | | which is - constructed from three separate pieces |
| packaging information. | | | | of corrugated fiberboard. The Bliss box was |
| Damage resulting from poor environmental control | | | | developed to be used when maximum stacking |
| during handling and transit is one of the leading | | | | strength is required. The bottoms and tops of all |
| causes of rejected produce and low buyer and | | | | three types of containers may be closed by glue, |
| consumer satisfaction. Each fresh fruit and | | | | staples, or interlocking slots. |
| vegetable commodity has its own requirements | | | | Almost all corrugated fiberboard containers are |
| for temperature, humidity, and environmental gas | | | | shipped to the packer flat and assembled at the |
| composition. Produce containers should be produce | | | | packing house. To conserve space, assembly is |
| friendly - helping to maintain an optimum | | | | usually performed just before use. Assembly may |
| environment for the longest shelf life. This may | | | | be by hand, machine, or a combination of both. |
| include special materials to slow the loss of water | | | | Ease of assembly should be carefully investigated |
| from the produce, insulation materials to keep out | | | | when considering a particular style of package. |
| the heat, or engineered plastic liners that maintain | | | | In recent years, large double-wall or even triple- |
| a favorable mix of oxygen and carbon dioxide. | | | | wall corrugated fiberboard containers have |
| Identification | | | | increasingly been used as one-way pallet bins to |
| The package must identify and provide useful | | | | ship bulk produce to processors and retailers. |
| information about the produce. It is customary | | | | Cabbage, melons, potatoes, pumpkins, and citrus |
| (and may be required in some cases) to provide | | | | have all been shipped successfully in these |
| information such as the produce name, brand, | | | | containers. The container cost per pound of |
| size, grade, variety, net weight, count, grower, | | | | produce is as little as one fourth of traditional size |
| shipper, and country of origin. It is also becoming | | | | containers. Some bulk containers may be |
| more common to find included on the package, | | | | collapsed and re-used. |
| nutritional information, recipes, and other useful | | | | For many years, labels were printed on heavy |
| information directed specifically at the consumer. | | | | paper and glued or stapled to the produce |
| In consumer marketing, pack- age appearance | | | | package. The high cost of materials and labor has |
| has also become an important part of point of | | | | all but eliminated this practice. The ability to print |
| sale displays. | | | | the brand, size, and grade information directly on |
| Universal Product Codes (UPC or bar codes) may | | | | the container is one of the greatest benefits of |
| be included as part of the labeling. The UPCs used | | | | corrugated fiberboard containers. There are |
| in the food industry consist of a ten-digit machine | | | | basically two methods used to print corrugated |
| readable code. The first five digits are a number | | | | fiberboard containers: |
| assigned to the specific producer (packer or | | | | Post Printed. When the liner is printed after the |
| shipper) and the second five digits represent | | | | corrugated fiberboard has been formed, the |
| specific product information such as type of | | | | process is known as post printing. |
| produce and size of package. Although no price | | | | Post printing is the most widely used printing |
| information is included, UPCs are used more and | | | | method for corrugated fiberboard containers |
| more by packers, shippers, buyers, and Example | | | | because it is economical and may be used for |
| of a UPC retailers as a fast and convenient | | | | small press runs. However, postprinting produces |
| method of inventory control and cost accounting. | | | | graphics with less detail and is usually limited to |
| Efficient use of UPCs requires coordination with | | | | one or two colors. |
| everyone who handles the package. | | | | Preprinted. High quality, full-color graphics may be |
| Types of Packaging Materials | | | | obtained by preprinting the linerboard before it is |
| Wood | | | | attached to the corrugated paperboard. Whereas |
| Pallets literally form the base on which most fresh | | | | the cost is about 15 percent more than standard |
| produce is delivered to the consumer. Pallets were | | | | two color containers, the eye catching quality of |
| first used during World War II as an efficient way | | | | the graphics makes it very useful for many |
| to move goods. The produce industry uses | | | | situations. The visual quality of the package |
| approximately 190 of the 700 million pallets | | | | influences the perception of the product because |
| produced per year in the U.S.. About 40 percent | | | | the buyer's first impression is of the outside of |
| of these are single-use pallets. Because many are | | | | the package. Produce managers especially like high |
| of a non-standard size, the pallets are built as | | | | quality graphics that they can use in super market |
| inexpensively as possible and discarded after a | | | | floor displays. |
| single use. Although standardization efforts have | | | | Preprinted cartons are usually reserved for the |
| been slowly under way for many years, the | | | | introduction of new products or new brands. |
| efforts have been accelerated by pressure from | | | | Market research has shown that exporters may |
| environmental groups, in addition to the rising cost | | | | benefit from sophisticated graphics. The increased |
| of pallets and landfill tipping fees. | | | | cost usually does not justify use for mature |
| Over the years, the 40-inch wide, by 48-inch long | | | | products in a stable market, but this may change |
| pallet has evolved as the unofficial standard size. | | | | as the cost of these containers becomes more |
| Standardization encourages re-use, which has | | | | competitive. |
| many benefits. Besides reducing cost because | | | | Pulp Containers. Containers made from recycled |
| they may be used many times, most pallet racks | | | | paper pulp and a starch binder are mainly used for |
| and automated pallet handling equipment are | | | | small consumer packages of fresh produce. |
| designed for standard-size pallets. Standard size | | | | Pulp containers are available in a large variety of |
| pallets make efficient use of truck and van space | | | | shapes and sizes and are relatively inexpensive in |
| and can accommodate heavier loads and more | | | | standard sizes. Pulp containers can absorb surface |
| stress than lighter single-use pallets. | | | | moisture from the product, which is a benefit for |
| Additionally, the use of a single pallet size could | | | | small fruit and berries that are easily harmed by |
| substantially reduce pallet inventory and | | | | water. Pulp containers are also biodegradable, |
| warehousing costs along with pallet repair and | | | | made from recycled materials, and recyclable. |
| disposal costs. The adoption of a pallet standard | | | | Paper and Mesh Bags. Consumer packs of |
| throughout the produce industry would also aid | | | | potatoes and onions are about the only produce |
| efforts toward standardization of produce | | | | items now packed in paper bags. The more |
| containers. | | | | sturdy mesh bag has much wider use. In addition |
| In the early 1950s, an alternative to the pallet | | | | to potatoes and onions, cabbage, turnips, citrus, |
| was introduced. It is a pallet-size sheet (slipsheet) | | | | and some specialty items are packed in mesh |
| of corrugated fiberboard or plastic (or a | | | | bags. Sweet corn may still be packaged in mesh |
| combination of these materials) with a narrow lip | | | | bags in some markets. In addition to its low cost, |
| along one or more sides. packages of produce are | | | | mesh has the advantage of uninhibited air flow. |
| stacked directly on this sheet as if it were a pallet. | | | | Good ventilation is particularly beneficial to onions. |
| Once the packages are in place, they are moved | | | | Supermarket produce managers like small mesh |
| by a specially equipped fork lift equipped with a | | | | bags because they make attractive displays that |
| thin metal sheet instead of forks. | | | | stimulate purchases. |
| Slipsheets are considerably less expensive than | | | | However, bags of any type have several serious |
| pallets to buy, store, and maintain; they may be | | | | disadvantages. Large bags do not palletize well and |
| re-used many times; and they reduce the tare | | | | small bags do not efficiently fill the space inside |
| weight of the load. However, they require the use | | | | corrugated fiberboard containers. Bags do not |
| of a special fork-lift attachment at each handling | | | | offer protection from rough handling. Mesh bags |
| point from packer to retailer. | | | | provide little protection from light or contaminants. |
| Depending on the size of produce package, a | | | | In addition, produce packed in bags is correctly |
| single pallet may carry from 20 to over 100 | | | | perceived by the consumer to be less than the |
| individual packages. Because these packages are | | | | best grade. Few consumers are willing to pay |
| often loosely stacked to allow for air circulation, or | | | | premium price for bagged produce. |
| are bulging and difficult to stack evenly, they | | | | Plastic Bags. Plastic bags (polyethylene film) are |
| must be secured (unitized) to prevent shifting | | | | the predominant material for fruit and vegetable |
| during handling and transit. Although widely used, | | | | consumer packaging. Besides the very low |
| plastic straps and tapes may not have completely | | | | material costs, automated bagging machines |
| satisfactory results. Plastic or paper corner tabs | | | | further reduce packing costs. Film bags are clear, |
| should always be used to prevent the straps | | | | allowing for easy inspection of the contents, and |
| from crushing the corners of packages. | | | | readily accept high quality graphics. Plastic films are |
| Plastic stretch film is also widely used to secure | | | | available in a wide range of thicknesses and |
| produce packages. A good film must stretch, | | | | grades and may be engineered to control the |
| retain its elasticity, and cling to the packages. | | | | environmental gases inside the bag. The film |
| Plastic film may conform easily to various size | | | | material "breathes" at a rate necessary to |
| loads. It helps protect the packages from loss of | | | | maintain the correct mix of oxygen, carbon |
| moisture, makes the pallet more secure against | | | | dioxide, and water vapor inside the bag. Since |
| pilferage, and can be applied using partial | | | | each produce item has its own unique |
| automation. However, plastic film severely | | | | requirement for environmental gases, modified |
| restricts proper ventilation. A common alternative | | | | atmosphere packaging material must be specially |
| to stretch film is plastic netting, which is much | | | | engineered for each item. Research has shown |
| better for stabilizing some pallet loads, such as | | | | that the shelf life of fresh produce is extended |
| those that require forced-air cooling. Used stretch | | | | considerably by this packaging. The explosive |
| film and plastic netting may be difficult to properly | | | | growth of precut produce is due in part to the |
| handle and recycle. | | | | availability of modified atmosphere packaging. |
| A very low-cost and almost fully automated | | | | In addition to engineered plastic films, various |
| method of pallet stabilization is the application of a | | | | patches and valves have been developed that |
| small amount of special glue to the top of each | | | | affix to low-cost ordinary plastic film bags. These |
| package. As the packages are stacked, the glue | | | | devices respond to temperature and control the |
| secures all cartons together. This glue has a low | | | | mix of environmental gases. |
| tensile strength so cartons may be easily | | | | Shrink Wrap. One of the newest trends in |
| separated or repositioned, but a high shear | | | | produce packaging is the shrink wrapping of |
| strength so they will not slide. The glue does not | | | | individual produce items. Shrink wrapping has been |
| present disposal or recycling problems. | | | | used successfully to package potatoes, |
| Pallet Bins. Substantial wooden pallet bins of milled | | | | sweetpotatoes, apples, onions, sweet corn, |
| lumber or.plywood are primarily used to move | | | | cucumbers and a variety of tropical fruit. Shrink |
| produce from the field or orchard to the packing | | | | wrapping with an engineered plastic wrap can |
| house. Depending on the application, capacities | | | | reduce shrinkage, protect the produce from |
| may range from 12 to more than 50 bushels. | | | | disease, reduce mechanical damage and provide a |
| Although the height may vary, the length and | | | | good surface for stick-on labels. |
| width is generally the same as a standard pallet | | | | Rigid Plastic Packages. packages with a top and |
| (48 inches by 40 inches). More efficient | | | | bottom that are heat formed from one or two |
| double-wide pallet bins (48 inches by 80 inches) | | | | pieces of plastic are known as clamshells. |
| are becoming more common in some produce | | | | Clamshells are gaining in popularity because they |
| operations. | | | | are inexpensive, versatile, provide excellent |
| Most pallet bins are locally made; therefore it is | | | | protection to the produce, and present a very |
| very important that they be consistent from lot | | | | pleasing consumer package. Clamshells are most |
| to lot in materials, construction, and especially size. | | | | often used with consumer packs of high value |
| For example, small differences in overall | | | | produce items like small fruit, berries, mushrooms, |
| dimensions Pallet bin can add up to big problems | | | | etc., or items that are easily damaged by crushing. |
| when several hundred are stacked together for | | | | Clamshells are used extensively with precut |
| cooling, ventilation, or storage. It is also important | | | | produce and prepared salads. Molded polystyrene |
| that stress points be adequately reinforced. The | | | | and corrugated polystyrene containers have been |
| average life of a hardwood pallet bin that is | | | | test marketed as a substitute for waxed |
| stored outside is approximately five years. When | | | | corrugated fiberboard. At present they are not |
| properly protected from the weather, pallets bins | | | | generally cost competitive, but as environmental |
| may have a useful life of 10 years or more. | | | | pressures grow, they may be more common. |
| Uniform voluntary standards for wood pallets and | | | | Heavy-molded polystyrene pallet bins have been |
| other wood containers are administered by the | | | | adopted by a number of growers as a substitute |
| National Wooden Pallet and Container Association, | | | | for wooden pallet bins. Although at present their |
| Washington, DC. Additionally, the American | | | | cost is over double that of wooden bins, they |
| Society of Agricultural Engineers, St. Joseph, | | | | have a longer service life, are easier to clean, are |
| Michigan, publishes standards for agricultural pallet | | | | recyclable, do not decay when wet, do not harbor |
| bins (ASAE S337.1). | | | | disease, and may be nested and made collapsible. |
| Wire-Bound Crates. Although alternatives are | | | | As environmental pressures continue to grow, the |
| available, wooden wire-bound crates are used | | | | disposal and recyclability of packaging material of |
| extensively for snap beans, sweet corn and | | | | all kinds will become a very important issue. |
| several other commodities that require | | | | Common polyethylene may take from 200 to |
| hydrocooling. Wire-bound crates are sturdy, rigid | | | | 400 years to breakdown in a landfill. The addition |
| and have very high stacking strength that is | | | | of 6 percent starch will reduce the time to 20 |
| essentially unaffected by water. Wire-bound | | | | years or less. packaging material companies are |
| crates come in many different sizes from half- | | | | developing starch-based polyethylene substitutes |
| bushel to pallet-bin size and have a great deal of | | | | that will break down in a landfill as fast as ordinary |
| open space to facilitate cooling and ventilation. | | | | paper. |
| Although few are re-used, wire-bound crates may | | | | The move to biodegradable or recyclable plastic |
| be dissembled after use and shipped back to the | | | | packaging materials may be driven by cost in the |
| packer (flat). In some areas, used containers may | | | | long term, but by legislation in the near term. |
| pose a significant disposal problem. Wirebound | | | | Some authorities have proposed a total ban on |
| crates are not generally acceptable for consumer | | | | plastics. In this case, the supermarket of the early |
| packaging because of the difficulty in affixing | | | | 21st century may resemble the grocery markets |
| suitable labels. | | | | of the early 20th century. |
| Wooden Crates and Lugs. Wooden crates, once | | | | Standardization of Packaging |
| extensively used for apples, stone fruit, and | | | | Produce package standardization is interpreted |
| potatoes have been almost totally replaced by | | | | differently by different groups. The wide variety |
| other types of containers. The relative expense | | | | of package sizes and material combinations is a |
| of the container, a greater concern for tare | | | | result of the market responding to demands from |
| weight, and advances in material handling have | | | | many different segments of the produce industry. |
| reduced their use to a few specialty items, such | | | | For example, many of the large-volume buyers of |
| as expensive tropical fruit. The 15-, 20-, and | | | | fresh produce are those most concerned with the |
| 25-pound wooden lugs still used for bunch grapes | | | | environment. They demand less packaging and |
| and some specialty crops are being gradually | | | | the use of more recyclable and biodegradable |
| replaced with less costly alternatives. | | | | materials, yet would also like to have many |
| Wooden Baskets and Hampers. Wire-reinforced | | | | different sizes of packages for convenience. |
| wood veneer baskets and hampers of different | | | | packers want to limit the variety of packages |
| sizes were once used for a wide variety of crops | | | | they must carry in stock, yet they have driven |
| from strawberries to sweetpotatoes. They are | | | | the trend toward preprinted, individualized |
| durable and may be nested for efficient transport | | | | containers. Shippers and trucking companies want |
| when empty. However, cost, disposal problems, | | | | to standardize sizes so the packages may be |
| and difficulty in efficient palletization have severely | | | | better palletized and handled. |
| limited their use to mostly local grower markets | | | | Produce buyers are not a homogeneous group. |
| where they may be re-used many times. | | | | Buyers for grocery chains have different needs |
| Corrugated Fiberboard | | | | than buyers for food service. For grocery items |
| Corrugated fiberboard (often mistakenly called | | | | normally sold in bulk, processors want largest size |
| cardboard or pasteboard) is manufactured in | | | | packages that they can handle efficiently - to |
| many different styles and weights. Because of its | | | | minimize unpacking time and reduce the cost of |
| relativity low cost and versatility, it is the | | | | handling or disposing of the used containers. |
| dominant produce container material and will | | | | Produce managers, on the other hand, want |
| probably remain so in the near future. The | | | | individualized, high quality graphics to entice retail |
| strength and serviceability of corrugated | | | | buyers with in-store displays. |
| fiberboard have been improving in recent years. | | | | Selecting the right container for fresh produce is |
| Most corrugated fiberboard is made from three | | | | seldom a matter of personal choice for the |
| or more layers of paperboard manufactured by | | | | packer. For each commodity, the market has |
| the kraft process. To be considered paperboard, | | | | unofficial, but nevertheless rigid standards for |
| the paper must be thicker than 0.008 inches. The | | | | packaging; therefore it is very risky to use a |
| grades of paperboard are differentiated by their | | | | nonstandard package. packaging technology, |
| weight (in pounds per 1,000 square feet) and their | | | | market acceptability, and disposal regulations are |
| thickness. Kraft paper made from unbleached pulp | | | | constantly changing. When choosing a package for |
| has a characteristic brown color and is | | | | fresh fruits and vegetables, packers must consult |
| exceptionally strong. In addition to virgin wood | | | | the market, and in some markets, standard |
| fibers, Kraft paper may have some portion of | | | | packages may be required by law. |
| synthetic fibers for additional strength, sizing | | | | |