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Module: Food Biotechnology

Technical Applications of Food Traceability

Dwiyitno1

Abstract

Traceability is the ability to trace and follow a food, feed, food-producing animal or substance intended to be or expected to be incorporated into a food or feed, through all stages of production, processing and distribution (Regulation EC No. 178/2002). The main objective of a traceability system is to record the history of a product since the raw materials used in the production and follows the process through the distribution to the consumer. Basically, there are 2 important aspects regarding the implementation of traceability, which are tracking and tracing system. GS1 (formerly EAN-UCC) is the most code system used world wide for traceability purposes. In the present time, bar code symbols are used globally as data carriers but other technologies, such as radio frequency identification (RFID) tags will be applied in the future. Nevertheless, DNA-based method, PCR in particular, is the most reliable method and widely employed in tracing back product origin. Accuracy, speed, completeness, reliability, validation and verification of the systems are important consideration in implementing traceability system.

Keywords: food traceability, barcodes, Radio Frequency Identification, polymerase chain reaction

1. Introduction

Food safety is an important part of food quality as are tracking and tracing systems

(traceability). There are several definitions for traceability. European Union (EU) defines

traceability as the ability to trace and follow a food, feed, food-producing animal or substance

intended to be or expected to be incorporated into a food or feed, through all stages of

production, processing and distribution (Regulation EC No. 178/2002). While in the U.S.

traceability is defined as the efficient and rapid tracking of physical product and traits from

and to critical points of origin or destination in the food chain necessary to achieve specific

food safety and, or, assurance goals (Golan et al., 2004). On the other hand, ISO 9001/2000

defines traceability as the ability to trace the history, application or location of that which is

under consideration. Additionally, labeling and traceability of genetically modified food

(GMF) are important issues that are considered in trade and regulation, particularly by EU

legislation (Regulation EC No. 1829 & 1839/2003).

The main objective of a traceability system is to record the history of a product since

the raw materials used in the production and follows the process through the distribution to

1 MSc in Food Science, Technology and Nutrition (SefotechNUT)   Email: dwiyitno@yahoo.com

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the consumer. Therefore, traceability system basically benefits to both producer and

consumer. Traceability system enables fewer products to be recalled and brings important

cost savings where the aim is to provide consumers with the high quality and safety products

which are produced in a cost efficient way (Asensio et al., 2007). Furthermore, benefits of an

efficient traceability system provide feedback on product quality to the supply chain and

improve consumer confidence. Currently, traceability systems can be incorporated into

information systems where consumers can get information on any product such as via

electronic data interchange/EDI (EAN, 2002).

The implementation of traceability has generated a significant amount of interest as

there is no single system accepted globally. Therefore, it is important to distinguish between

legal requirements and technologies required for providing a track and trace capability. The

traceability system should enable efficient food safety management, but it is the

responsibility of individual companies and supply chains to voluntarily take advantage of the

capabilities it provides (EAN, 2002). The aim of this paper is to review the technical

application of food traceability, particularly the common tracking techniques as well as

analytical methods availability for tracing back purposes.

2. The implementation of food traceability

Since 1 January 2005, the EU regulations oblige that all food and feed business

operators to establish traceability systems, even when their customers do not require it.

Traceability is also mandatory for beef in Japan, while exported beef in Australia, Argentina

and Brazil is obliged to be traceable. Conversely, up to date traceability is voluntary in the

U.S. (Souza-Monteiro & Caswell in Smith et al., 2005). In order to be able to trace products

and retrieve related information, producers have to provide information and keep track of

products during all stages of production, including primary production, processing,

distribution, retailing, and consumer (Schwagele, 2005). Furthermore, traceability requires a

verifiable method to identify growers, fields and produce in all its packaging and

transport/storage activities at all stages of the supply chain.

Basically, there are 2 important aspects regarding the implementation of traceability,

which are tracking and tracing system (Figure 1). Product tracking is the capability to follow

the path of a specified unit of a product through the supply chain, whereas product tracing is

the capability to identify the origin of a particular unit and/or batch of product located within

the supply chain by reference to records held upstream in the supply chain (EAN, 2002). The

implementation and maintenance of the traceability regulations require an effective and

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efficient system to track and trace back the products. Consequently, methodologies for the

analyses of the food materials combined with information technology systems are essential to

establish a working tracking and tracing system (Schwagele, 2005).

Figure 1. Tracking and tracing system along food chain

By the new EU regulation of traceability, the food processor is obliged to ensure that

the food products meet the requirements of food law in which previously it was sufficient for

a processor to be able to identify the source of an ingredient. This implies that the source of

all materials involved can be traced and a processor must therefore be able to prove that his

suppliers can provide full traceability. If any problem is suspected, tracking must go as far as

the consumer (Schwagele, 2005). Traceability covers everything that happens to the products

before, during and after the manufacturing, packaging, and distribution (Figure 2).

Figure 2. Traceability link management (GS1, 2006)

GTIN1 Lot B

GTIN1Lot A

SSCC1

SSCC2

SSCC3

SSCC4 SSCC7

SSCC5

Production

GTIN1

GTIN2

GTIN2

GTIN2

GTIN2

GTIN2

GTIN2

SSCC6

GLN1

GLN2

GLN3

GLN4

GLN6

GLN5

Logistic unit of raw materials Production line Trade item lots Grouping unit

Logistic unit of final products

Original location

Destination location

Reception Packaging Storage or Preparation for

shipping

Production

DESTINATION PRODUCTION UPSTREAM SUPPLIERS

Tracking

Provision of information downstream

Tracing

Provision of information upstream

Primary Producer

Processing Company Distributor Retail Consumer

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3. Tracking application for traceability

A product traceability system requires the identification of all the physical properties

from which the product originates, including the location where it is originated, processed,

packaged, and stocked (Regattieri et al., 2007). In order to keep track of items within a food

supply chain it is crucial to identify items in each step of the chain. This application is done

by data carriers as mark or tag that follows the item and can be read further down the supply

chain. Data carriers carry an identifier which is a character based or alphanumeric code.

There are 2 types of information are comprised within data carrier, i.e. primary and secondary

identification (CDCT, 2007). Primary identification is used to determine the identification of

a unit, by recognizing a set of features that can be considered characteristically unique for the

concerned unit. The identification method can be DNA or other molecular based analytical

methods. Nevertheless, secondary identification is an identifier to a unit, in a form that can be

attached to a unit through or partly through the supply chain. The identifier can be thought of

as a code, often as a number or an alpha-numeric string.

In recent tracking and tracing systems, GS1 (formerly EAN/UCC) is universally

accepted as an identification and communication system. Established by EU (1977),

European Article Number (EAN) International and the global partner organization for the

USA and Canada, the Uniform Code Council (UCC), today have more than 1,000,000

member companies in over 145 countries. Not only to identify goods, the code system also

provides for additional information such as best before date, serial number, location number

and batch number to be shown in a bar coded form. These identifying numbers are also used

in electronic commerce (GS1, 2007).

The GS1 system consists of three components (GS1, 2007): (1) Identification numbers;

used to identify a product (Global Trade Item Number-GTIN), location (Global Location

Number-GLN), logistic unit (Serial Shipping Container Number-SSCC), service or asset

(Global Returnable Asset Identifier-GRAI); (2) Data carriers; the barcodes or radio frequency

tags used to represent these numbers. The data carriers vary according to the level of

information required or the space available; and (3) Electronic messages; the means of

connecting the physical flow of goods with the electronic flow of information. These

technologies have been used in meat traceability, providing a robust tracking system for most

elements of the meat chain (Electronic Data Interchange/EDI) (Schwagele, 2005). Table 1

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illustrates the traceability practices in producing meat and meat product. Typically,

traceability is employed since animal production, slaughtering, processing to distribution.

Table 1. A process line of traceability of meat and meat products

SLAUGTERHOUSE 1st CUTTING HALL nth.. CUTTING HALL PROCESSING

INDUSTRY RETAIL

Carcass label Technical piece label for groupings of items

& pallets

Meat product label on bulk item,

groupings of trade items & pallets

Retail trade item labels for pure meat & meat

products

NO bar code Bar code: GS1-128 Bar code: GS1-128 Bar code: GS1-128 Bar code: GS1-13

Accompanying document of the animal SANITEL number (ear tag)

Carcass label GTIN Net weight (optional) Country of birth Country of fattening Country of slaughter Approval nr. Slaughterhouse Slaughtering date (optional) SANITEL number

Technical piece label 1. Meat from one animal Idem carcass label, but Cutting date, Best before date Country of cutting Approval nr. of cutting hall 2. Meat from more than one animal GTIN, Net weight Cutting/Best before date (optional), Lot nr.

Label on a bulk item GTIN Net weight (if variable weight ) Processing date (optional) Best before date (optional) Lot or SANITEL nr.

Label on pure (beef) meat GS1-13 + info in text format Label on meat products GS1-13 + info in text format (according to the rules of minced meat, meat preparations & food products)

Label for groupings of trade items Idem technical piece variable count Pallet label Uniform mono/multi-lot pallet SSCC GTIN content of the pallet Cutting/ Best before date variable count Net/Gross weight Lot nr. (only for mono-lot pallets) Mixed pallet SSCC + Gross weight + data identical for the whole pallet + other info via EDI

Label for groupings of trade items Idem bulk item variable count Pallet label Uniform mono/multi-lot pallet SSCC GTIN content of the pallet Processing/’Best before’ date variable count Net/ Gross weight Lot nr. (only for mono-lot pallets) Mixed pallet SSCC Gross weight data identical for the whole pallet other info via EDI

WHOLESALER /TRANSPORT OPERATOR GS1-13 for retail trade items GS1-128 for other packages Same indication requirements as the previous phase, unless other agreements with the client.

Source: EAN (2002).

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3.1. Tagging

Tagging is the most traditional way of tracking. Originally, tagging is practiced to

identify rearing animal such as cattle, goat and sheep, particularly to protect from the theft

and exchange in pasture area. Recently, tagging is also beneficial for production practice

verification. Right identification may ascertain authentication of permitted production

practices (e.g., grass-fed, free-range, raised/handled humanely) versus prohibited one (e.g.,

antibiotics, hormonal growth promotants, fed animal by-products) during rearing of the

animals (Smith et al., 2005). There are various types of animal tagging, most of which are ear

mark, neck tags, body mark and tail mark. Application of RFID technology by implanting a

chip into the body is the advanced technique employed for animal tagging (Regattieri et al.,

2007).

3.2. Alphanumerical codes

Alphanumerical codes are a sequence of numbers and letters of various sizes placed on

the labels of the product or on its packaging (Regattieri et al., 2007). The design phase of this

system is very simple and economic, but its management is so cost as requires significant

human resources for code writing and reading manually. Another limitation of

alphanumerical code is no specific standards defined and they are generally owner codes.

Consequently, the performance is not particularly good while the risk of data integrity

corruption is also high. Typically, alphanumerical code is employed for internal traceability

system.

3.3. Bar codes

Nowadays, bar codes are the most widely employed as tracking technique. Generally,

bar codes contain a series of numbers reflecting type of product and manufacturer. EAN-

UCC, now known as GS1, is the most bar coding standard employed worldwide. The

fundamental principle of bar coding system is an unambiguous numbering schema used to

identify goods or services throughout any supply chain. Using automatic data capture

techniques, this numbering system can be applied successfully at every stage of production or

transformation and distribution (GS1, 2007).

Several types of barcode are established by the different providers. The most common

bar code provided by GS1 standard are linear, stacked (multi rows), and 2 dimensional (Data

Matrix) (Figure 3). Typically, a linear bar code consists of a series of vertical parallel and

adjacent (dark-colored) bars and (light-colored) spaces. Predetermined width patterns for bars

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and spaces are used to encode and represent actual data in the bar code. This data can be the

GTIN itself or any additional information attributed to the item. A bar code reader (scanner)

decodes the width patterns of the bars and spaces. The combination of bar code labels and

scanners allows real-time data capture (EAN, 2002).

linear code (GS1-13) Stacked code (Databar) 2D code (Data matrix)

Figure 3. Different types of bar codes

Linear barcodes is the simplest and therefore the most extensively used. GS1 linear

barcode varies in the number of identity code. The most common bar codes are GS1-8, 12, 13

or 14 for retail packaging and GS1-128 for storage and shipping purposes. GS1-13 consists of

13 digit of GTIN while GS1-128 comprises 18 GTIN code and such additional information.

Beside GTIN, information possible on GS1-128 bar codes are either lot number, best before

date, price, net weight or country of origin (Figure 4). In term of beef labeling, for instance,

the label must contain the following mandatory elements: (1) reference number or reference

code ensuring the link between the meat and the animal or a group of animals; (2) country of

birth; (3) country of fattening; (4) country of slaughter; (5) country/countries of cutting; and

(6) approval number of the slaughterhouse and cutting hall. The GTIN itself does not contain

any information about the product; it is just a world wide unique and unambiguous

identification number (EAN, 2002).

Figure 4. An example of GS1-128 carcass label (EAN, 2002)

Viande Belgique N.V CARCASS bovine category XYZWeight: 425.8 kg

GTIN : 95487722000255 Reference number : BE51487721 Born in : Belgium Fattened in : Germany, Austria Slaughtered in: Belgium Approval nr slaughterhouse: UD1098H

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A stacked barcode contains between 2 and 8 rows, each separated by a separator bar.

Each row contains 16 words (which are generated from character pairs) and a start and stop

character. The last row also contains the number of rows in the symbol and the check digit

characters. There are 2400 possible words which can be generated from each pair of

characters. Symbols with less than 7 rows comprise 2 check digits in the final row. Symbols

with 7 or 8 rows contain 3 check digits in the final row. A numeric mode allows 5 digits to be

encoded in the same space as three alphanumeric characters, so offering a higher density. On

the other hand, two dimensional code is made up of square modules arranged within a finder

pattern. Data Matrix is known as 2D code provided by GS1 with symbols may be square or

rectangular. Data Matrix symbols can encode the entire ASCII character set and uses multiple

encoding modes which have the higher combination capacity i.e. 3100 digits for double digit,

2300 characters (alphanumeric text), 1550 bytes (byte values) (EAN, 2002).

3.4. Radio Frequency Identification (RFID)

The limitation of bar code tracking technique is the requirement to keep the bar code in

the proper way in order to be read by the scanner device precisely. Damage and unclean bar

are often problems on the successful application of bar code, particularly in farm purposes

(Schwagele, 2005). RFID technology may overcome this problem by using radio signals

instead of line of sight for identification, and can be integrated into a prototype recording

system. RFID technology is known more sensitive than bar code. Studies indicate that the

RFID achieve successful reads over 98% of the time, with unprotected and reused tags (Watts

et al., 2003). On the contrary, scanners can operate with a 90% success rate where

contamination levels are kept below 10% and barcodes are kept clean and undamaged

(Schwagele, 2005). Recently, RFID tags have been employed as individual track for cattle in

Japan, Canada and South Korea (Smith et al., 2005). In retail companies, RFID technology is

has been used such as in Walmart (USA), Tesco (UK) and Metro group (Germany).

RFID tags are often foreseen as the promising tracking technology to replacing

barcodes in the future. RFID tag data capacity is big enough that any tag will have a unique

code since the product may be individually tracked as it moves from one location to another

location. This may help companies to combat theft and other forms of product losses (Golan

et al., 2004). Moreover, the tracing back of products is an important feature that gets well

supported with RFID tags containing not only a unique identity of the tag but also the serial

number of the object. This may help companies to cope with quality deficiencies and

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resulting product recalls. However, product identifiers (tags) are not currently in widespread

use, and are expensive in comparison to the barcode. The storage of data associated with

tracking items will require many terabytes on all levels. Problems on penetration also arise

with respect to metals and other conductive media (Foodtrace, 2004).

3.5. Electronic Data Interchange (EDI)

Electronic Data Interchange (EDI) is the system of exchange of the data among trading

partners via electronic media. EDI offers a more efficient and reliable way of communicating

large amounts of data through the supply chain (GS1, 2007). Traditionally, documents

regarding product identity for shipment are delivered via paper documents. This conventional

system is known less effective, time consuming as well as more costly. Through EDI system,

the documents, including product identity, could be delivered via electronic means which is

faster and more effective as the data is integrated automatically with the existing online

system (Figure 5). Implementing EDI system is also beneficial for logistic management as it

automatically monitors the input-output item stock. As traceability requires a good

management system of record keeping a long whole steps of chain, implementation of EDI

system provide significant benefit in either tracking or tracing purposes by means of

computer to computer system.

Figure 5. Traceability link management (GS1, 2007)

4. Tracing methods of product origin

With respect to traceability along the full supply chain, particularly for meat and meat

products, needs such administrative implication on tracing systems. Several aspects are

importance to be involved, such as information on animal species, origin, authenticity, age,

composition and production system (Schwagele, 2005). Specifically, Regulation (EC)

2065/2001 for example, traceability on fish product requires the following information:

species of origin (fish species), geographical origin (fish from different regions), and method

Upstream supplier Production Distribution

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of production (wild or farmed, organic or intensive) (Moretti et al., 2003). Initially, products

are traced back for particular purposes such as product recall and investigating complaints.

The Sanitel system including an automatic treatment of data related to animal

identification and registration is the general way to assure animal origin. Moreover, the

Sanitel system includes an individual identification of the animal by a number present on an

earring tag. The main disadvantage of this system is that the traceability stopped at the

slaughterhouse. It is therefore almost impossible to link a piece of ear tag with the distributed

meat. Moreover, the administrative traceability is not unfailing, the lost of documents and the

risk of cheating are potentially occurred (Goffaux, et al., 2005). Therefore, it is necessary to

have reliable methods, which allow a fast and unequivocal identification of animal species.

Several techniques are available for the tracing analysis, particularly for food

authenticity. DNA-based and protein-based detection methods are the main technique

employed. Polymerase chain reaction (PCR) is the most DNA-based method employed, while

enzyme-linked immunosorbent assay (ELISA) works on protein-based method. In addition,

new methodologies are developed, including the use of microarrays, mass spectrometry, and

surface plasmon resonance (Miraglia et al., 2004; Peres et al., 2007).

4.1. DNA-based methods

DNA-based techniques have demonstrated as fast, cheap and straightforward gene

identification (Mackie et al., 1999; Weder et al., 2001). PCR has been developed into a key

technology for species identification in foods and feeds. PCR-RFLP (restriction fragment

length polymorphism) has been used for the species identification of food relevant animals

and plants. Random amplified polymorphic DNA-PCR (RAPD-PCR) as well as assays based

on single strand conformation pattern (SSCP) were developed for species and variety-specific

identification of different animals and plants (Rehbein et al., 1999; Weder, 2002).

The latest speciation techniques are the analysis based on mitochondrial DNA and

ribosomal RNA (Pineiro et al., 1999). DNA-based techniques have the advantage that one

does not need a standard for each tissue, because almost all the cells in an individual have the

same genomic DNA. Additionally, real time quantitative PCR (QPCR) has been widely

applied for the DNA amplification due to simplicity, specificity and sensitivity, chiefly for

the restriction fragment length polymorphism (RFLP) technique (Weder et al., 2001). QPCR

is the most reliable technique for the quantification of genetically modified organisms

(Schwagele, 2005).

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DNA sequence information can also be used for species identification. The

development of modern molecular biology techniques including various sequencing

techniques has led to a large number of base sequences (Schwagele, 2005). Unfortunately,

not all of them are available in the various DNA databases. For species identification, the

mitochondrial DNA (mtDNA) is the most widely used target molecule. The main reason to

use mtDNA for this kind of analysis is the availability of numerous sequences in databases

and the high genetic variability of mtDNA, which allows sophisticated primer design for

sequencing. DNA sequencing is theoretically the most informative and precise technique but

requires samples consisting only of a single species. Sequencing allows species identification

without reference material if the generated sequence is available in a database.

4.2. Protein-based methods

Proteins (enzymes, myoglobin, etc.) have been widely used as species markers.

Applicable techniques include separation of water-soluble proteins by starch, polyacrylamide

or agarose gel electrophoresis, isoelectric focusing (IEF), and two-dimensional

electrophoresis (Pineiro, et al., 1999; Martinez, 2007). Highly resolved water-soluble protein

patterns can be used to differentiate genetically close-related species. The limit of detection

of gel electrophoretical methods varies between 0.1% and 1% and depends on the

visualization procedure of the proteins bands.

Immunological techniques, on the other hand, like ELISA performed on the solid

surface of microwell plates are using suitable target proteins for analysis. A qualitative

detection of animal species is possible and the limit of detection depends upon their content

in meat products (pork 61%; poultry and beef 62%; sheep 65%) (Schwagele, 2005). Notably,

proteomics can be used to differentiate species, breeds, and varieties by their specific protein

pattern.

5. Considerations on implementing traceability system

An efficient and effective system of traceability can significantly reduce operating costs

as well as increase productivity. At the same time, such a system provides product safety

elements and thus makes consumers safer. In order to establish product traceability system,

particularly on food traceability system, there are 4 fundamental concepts must be taken in

account (Regattieri et al., 2007). Accordingly, those aspects are product identification, data to

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trace, product routing, and traceability tools (Figure 6). The implementation of traceability

system, thereby, should consider to the concerned product properties.

Figure 6. Framework for product traceability (Regattieri et al., 2007)

In practice, different technical approaches can be used for tracking system. The data

accuracy and reliability required can guide the selection of the traceability tool. Accordingly,

cost is a relevant factor and so must also be taken into account. Final choice must consider

the degree of compatibility with the product and the production process, the degree of

automation supported by the supply chain analyzed, and in general knowledge along the

supply–production chain (Regattieri et al., 2007). Traceability system has to describe

extensively to which the origin of all the raw materials used and the distribution of the

finished products can be defined precisely and thereby could be identified unambiguously.

Additionally, traceability system has to be able to identify which hazards are focused in the

system as well as the specific time of the tracking-tracing practices (online, hours, days or

weeks). Therefore, aaccuracy, speed, completeness, reliability, validation and verification of

the systems are important considerations in implementing traceability system (GS1, 2007).

Bar codes (mainly the GS1 system) are currently widespread used in tracking system as

they offer several significant advantages. With an integrated system, the process of entering

information into retailers’ systems is automated so when new information is logged into the

system by the producer, it is added in real time to all systems across a network. With such

systems, anyone along the chain can track inputs, production, and inventory by an array of

characteristics (Golan et al., 2004). However, RFID technology is known as the promising

technology due to the higher accuracy and efficiency on identifying items compare to bar

codes (Watts et al., 2003). By the time of reducing cost of production, RFID technology will

be eventually replacing bar codes technology.

PRODUCT IDENTIFICATION DATA TO TRACE PRODUCT ROUTING TRACEABILITY TOOLS

dimensions volume weight

surface conditions shortness

perishability packaging

cost life cycle length

bill of material structure

number typology

degree of detail dynamism

data storage requirements

confidentiality & publicity

checks & alarms

production cycle activities lead times

equipments manual operations

automatic operations

movement systemsstorage systems

compatibility vs productcompatibility vs process

N° of data readings N° of data writings degree of automation

data accuracy data reliability

company’s knowledge cost of system

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6. Conclusion

1. The benefits of traceability system on food production and distribution will be achieved

only if implemented comprehensively within all steps of food supply chain.

2. At the present time, bar code symbols are used globally as data carriers, but other

technologies such as radio frequency identification (RFID) tags will be applied widely in

the future.

3. DNA-based method, PCR in particular, is the most reliable method and widely employed

in tracing product origin.

4. GS1 (formerly EAN-UCC) is the most code system used world wide for traceability

purposes.

5. Accuracy, speed, completeness, reliability, validation and verification of the systems are

important considerations in implementing traceability system.

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