At any level, process control will not only improve food quality, but also enhance food safety.

Food quality and food safety go hand-in-hand. Yet it may not be obvious that applying controls, such as statistical process control (SPC), to processes not only goes a long way to producing consistent quality results, it also can minimize waste and improve food safety.¹

In a 1997 survey of UK food processors conducted by Nigel P. Grig, Glasgow Caledonian University, food processors’ adoption of SPC typically fell into three categories: “We can, and we do,” “We can, but we don’t,” and We want to, but we can’t.” Unfortunately, many processors today still fall into the last two categories. Grig points out some of these processors feel SPC is unnecessary or that it is difficult to understand and implement.²

Fortunately, the tools to fine-tune processes are much easier to use today, and they’re capable of minimizing waste, finding process problems and improving throughput and quality while maintaining food safety, provided an effective HACCP plan is in place. Many processors have more of the necessary tools than they realize—they just don’t talk to each other, and making them talk often requires the help of a system integrator.

“What we’re seeing is that food safety and quality are highly related,” says Evan Miller, Hertzler Systems president. “After all, how could you pay attention to either safety or quality, and neglect the other?”

In fact, this interrelationship should be considered in the design phase of any process and its controls. “In all our designs, food safety and food quality are both integral parts of our considerations and efforts,” says Jim Shortridge, SSOE Group senior project manager/food. “Both food safety and food quality are tightly coupled design principles, as a miss in one category will directly impact the value of the other. Both always go hand-in-hand.”

Miller points out another good reason for adopting controls. “Food processors seem to be maturing to higher standards for data traceability and trend analysis. Part of this seems to be driven by a need for accountability systems so they can go to sleep at night, knowing people are paying attention to these critical aspects of the business.”

Beyond data traceability, today’s process control equipment archives data through HMIs and historians, and the data can also be used to improve quality. Chris Farver, director of controls and information at Heat and Control, says users of its ITM-Plant iT system can call up operational data from the previous two years and play it back as though it were in real time. All the data is tracked and displayed, along with all plant personnel changes to the program, and they’re time stamped. “This also allows the quality department to help establish a ‘best-in-class’ production setup,” adds Farver.

Does controlling food quality imply food safety is under control?

The short answer, of course, is no—and neither is the inverse necessarily true. But both goals are necessary if a processor wants to stay in business. “Food safety and food quality are not one and the same, but both are interdependent and paramount to food manufacturers in safeguarding their brand reputation,” says Katie Beissel, global industry manager—food and beverage, GE Intelligent Platforms.

“Food safety and quality aren’t necessarily synonymous,” says Mike Edgett, Infor director, industry marketing, process manufacturing. “You can have a product that is poor quality (e.g., over processed) that will not taste very good but still not be a safety concern.” However, Edgett says the two are synonymous when it comes to the impact on a processor’s growth. Consumers aren’t likely to buy the same food again if the quality is poor, or if it’s unsafe.

There are, however, varying opinions of what process control is and how it should be used to achieve both food safety and quality goals. “When we use the term ‘process control’ in food manufacturing, we evoke the idea of sophisticated manufacturing control systems and elaborate statistical graphs of microbiological or other analytical data,” says Dr. Lee Johnson, vice president  of technical services, West Liberty Foods, in a paper, Control the Process, Control Food Safety. “This is certainly the mainstream method of operations when detail is critical to the food safety systems, such as temperature or pH control.”

Johnson suggested, in a separate interview, that the principles of process control in the management of food safety don’t apply just to data capture. “Process control is not confined to SPC run charts or fancy computer controllers, but as simple as making sure people entering a processing area wash their hands. Anything that you are controlling [to produce] an outcome, is by definition process control, so hopefully everything in a manufacturing area.”

Today’s SPC systems are not complicated to use, but processors have a hard time seeing value in them unless they provide a tangible business advantage, such as reducing giveaways, preventing waste and directly improving the bottom line, according to Mike Gay, Rockwell CPG industry manager. Gay says SPC will be used for other process parameters such as brix or pH to assure quality, but food safety is just assumed. “No one is going to sell a system on ROI when it comes to food safety, because there isn’t an ROI,” says Gay. “You’re in business to make a product that you sell. If you don’t make it safely, you’re not going to be in business very long.”

While there may not be an obvious ROI to any system dedicated to food safety—as opposed to quality—a limited recall to just the product affected certainly saves dollars over a blind recall consuming weeks or months of product. “Payback is not truly apparent until you have a problem and [are] forced to go after far more product than was really affected,” says West Liberty Foods’ Johnson. “The investment in advanced technologies is easy to justify for larger companies that are producing high volumes of product, as small problems get very large in a hurry without good lotting and tracking programs.”

Instrumenting HACCP

HACCP focuses specifically on food safety, and it needs to be the underlying structure of any process, whether or not the process is automated. HACCP is so critical to quality that it is the first subject discussed on the quality page of Oak State Bakery’s website. “Documented Hazard Analysis Critical Control Point (HACCP) plans are developed and in place for all products made by Oak State. HACCP—a system for food safety control employs a proactive and preventive approach to control potential hazards and provides a mechanism to reduce food safety risks.”

However, HACCP is not a standalone program and should be part of a larger food safety management program. Oak State, a contract bakery, develops prerequisite programs to control the conditions in the plant environment, which contribute to the overall safety of products. Prerequisite programs are developed, implemented and documented before putting a HACCP plan in place.³

While some processors have been dragging their feet with instrumenting their HACCP plans, they need to think about the other benefits that automation can bring. “Surprisingly, some of the old ways [chart recorders, clipboards, spreadsheets] are still prevalent, especially with the smaller, independent food providers,” says SSOE Group’s Shortridge. “When we are engaged in a new project, having a frank discussion with the client to better understand its vision of where it wants to be in one, three or five years  is paramount in our approach. While focusing on the key project needs, we bring options to the table that enhance food safety and food quality; provide a higher OEE [overall equipment effectiveness]; and take them a step closer to greater process automation and operational excellence.”

Today, instrumentation and controls are more affordable than ever, so key areas of the process (which also include, for example, refrigerator and freezer storage) can be monitored electronically and controlled. Some key process variables include temperature, pressure and pH. While a processor can pay more than $6,000 for a wireless temperature transmitter that might be used in a refinery, lower-priced solutions provide the same accuracy, durability and performance. The same is true for programmable controls. Yesterday’s $10,000-plus PLC can be replaced by mini-PLCs and controllers in the under-$500 range.

Electronic recordkeeping and audits

“We are seeing an explosion of instrumentation,” says Gary Kohrt, Iconics vice president of marketing. Every temperature and process variable that affects the food product is recorded and used for operational improvement and, most importantly, product quality and recordkeeping, adds Kohrt. Historians are a way to maintain data for years and can satisfy FDA 21 CFR Part 11 requirements for electronic recordkeeping.

For food storage, Stellar Automation provides a PLC-based system with HMI to control room temperature and pressure, according to Kevin Frantz, Stellar automation manager. “This information is viewed and stored, and we use daily reporting software to provide temperature reports that allow our customers to keep accurate records of their food storage. They use this historical data if they are audited,” says Frantz.

Two distinct advantages of electronic recordkeeping are minimizing human error and the capability to store electronic signatures. “To ensure that line operators follow HACCP procedures, for example, manufacturers can automate and manage HACCP monitoring, integrate real-time production work processes and enable faster response times to compliance issues with immediate corrective actions,” says Beissel.

The problem is that not everyone is using electronic recordkeeping. “We still find an abundance of circular chart recorders to capture temperature or cook cycles,” says Shortridge. “As we move into new automation opportunities, we look at the current data infrastructures to better understand the state of their operations from an automation/MES perspective.” Shortridge then checks whether the processor uses a data historian that will allow it to capture regulatory data when needed/able. He also provides education to introduce the processor to plant-wide data management and web-based reporting, especially for regulatory needs. If a processor is far enough along in data collection and tracking, Shortridge discusses lot tracking and reporting.

Today’s chart recorder often has a digital system running in parallel with it, so the chart recorder’s limitation is covered by digital storage of the same data, according to Gay. The chart recorder’s main limitation is that of scale. If it’s set up with 24-hour gradations on it, and a pasteurization process runs several times per hour with two-minute kill steps, most of what will be seen on the chart will look like a constant black line with up-and-down temperature swings that will be very difficult to correlate with time. Besides the inability to get precise time vs. temperature readings off the chart, other disadvantages are the storing and relocating of the chart in case of a food safety problem or recall.

Getting started with process controls to improve food safety

For processors that use manual methods to log and store process data but want to shift toward automating some of these steps, design/build services, system integrators and automation suppliers stand ready to help. “Our initial role is one of listening to gain clarity of the problems [processors] face,” says Shortridge. Jointly, key process safety parameters are defined to ensure they are monitored and controlled properly and help drive the process in general. “Where needed, we provide education on food safety and food quality including from a controls perspective,” adds Shortridge. “We orientate our controls and automation solutions to support food safety while supporting a path toward operational excellence.”

Based on its experience in helping food and beverage processors undertake this challenge, GE Intelligent Platforms developed what it calls the Operational Excellence (OpEx) Journey, which ties food quality and food safety into the overall business need to deliver value-added results. This is a five-step process, according to Beissel, that guides manufacturers in the most cost-effective way to implement a plant strategy to:

1. Provide real-time visibility and control of baseline performance metrics at line side and to supervisory staff.
2. Profile critical process parameters related to throughput to drive improvements in asset efficiency and reliability.
3. Drive production consistency by integrating manual and automated work process to reduce waste and improve quality and food safety.
4. Analyze the effects of raw materials and their impact on asset performance to improve yields of raw materials.
5. Use manufacturing effectiveness data to support supply chain optimization and production planning.

Fortunately, for manufacturers that buy OEM processing or packaging equipment, food safety and quality issues are addressed by the suppliers. For example, if a processor buys an OEM pasteurizer that uses Rockwell Automation components, Rockwell will work with the OEMs to create a unit that provides the processor with a very stable platform to run its business, says Gay. “Does the processor really care whether the pasteurizer has a lot of automation in it?” As long as the machine works and can provide acceptable information to FDA showing it hit the right product temperature and held it, and was cleaned according to specification, the processor doesn’t need to be any more involved in the unit’s workings.

“We certainly don’t expect processors to develop complex automated control systems,” says Heat and Control’s Farver. “That’s our field of expertise. We work closely with each processor to identify and pre-load all process control parameters into our software before it is activated. The processor knows what performance and product quality it wants from its equipment. We simply give it the tools and training needed to monitor and control the line in real time and to retrieve operational data for evaluation.”

Enhancements to make food safety/quality easier

Many enhancements to software systems have been developed to meet the control needs of a diverse set of applications—from track and trace/supply chain to process control/HMI/SCADA and other basic problems with equipment on the plant floor.

Hertzler’s Miller listed a few examples: data acquisition from any data source, dashboards for exception monitoring and statistical trend analysis for the early detection of process shifts. “Probably the most important tool to control a food/beverage process and demonstrate consistency and safety is the SPC chart,” says Miller. The chart, which tracks and manages food safety and quality, helps the user identify types of variation in the process (either common or special cause) so the user knows when to act, and when to leave the process alone.

Another tool is the quality/food safety line display dashboard, which can be tailored for a processor’s needs, says Miller. For example, one processor developed a color-coded display that informed the entire pack area when each machine was due for a metal detection test, and then verified the check was done.

A new version of a MES from Invensys Operations Management, Wonderware MES 2012 with Quality Software, includes a quality suite, which can reduce the cost of quality management while improving regulatory and product safety compliance by capturing complete product, equipment and process-related quality data for both automated and manual operations. “Enhancements to the software reduce distracting and difficult-to-manage operator tasks, as well as secure compliance and product safety in ever-changing environments,” says Rob McGreevy, vice president of platform and operations software. “Integrating systems, data and processes enables better operations management and increases value within manufacturing.” SPC trending and charting are available for near real-time quality monitoring, and include notifications of violations of control and specification limits.

“When it comes to overall food safety, Infor can help manufacturers maintain an active approach to HACCP management,” says Edgett. “For example, improper changeover procedures, poor sanitation measures, leaky pipes or roofs, metal shavings that fall into packaging and other asset maintenance issues have led to several high-profile recalls. These recalls could have been prevented.” Policies and software solutions that enforce preventive maintenance safeguard product quality, reduce safety risks and boost asset availability and longevity. Additionally, using alerting technologies that warn when conditions change, which may compromise food safety (such as when the temperature is too low or the humidity is too high), can also significantly reduce the risks for contamination, says Edgett.

One tool, written specifically for HACCP in USDA primary processing facilities, has been enhanced to assist processors that wish to achieve compliance with SQF, BRC and other certifications, says Pat Graham, CAT² technical sales manager. HAT or Hazard Analysis Toolkit focuses on proactively controlling processes and preventing failures. Processors can use the food safety and quality management tool to guarantee products meet HACCP, HIMP, USDA, FDA, QC, QA and SOP/GMP specifications.

“Capturing digital signatures using GE Proficy solutions can ensure accountability with electronic recordkeeping processes,” says Beissel. In addition, the software’s ability to manage specifications and use them to trigger proactive work instructions enables operators to act as fast as possible. Real-time alarming and trending notifications let manufacturers take the right corrective actions to limit liabilities and cost.

“We are not software developers,” says SSOE’s Shortridge. “In our role of making food clients successful by saving them time, trouble and money, we tailor commercially off-the-shelf software to meet food safety and food quality requirements. We ensure our systems have the ability to track and alarm on key food safety metrics such as time at temperature, food exposure times and metal detection to name a few. We use controls to monitor and ensure kill steps are met; identify, validate and alarm on critical control points; and ensure CIP steps are complete, production permissives are in place, and correct process steps are followed.”

Controlling quality and food safety through batching

When operators manually perform and log process steps for a recipe, it’s easy to get distracted through interruptions from other employees and managers, breaks, phone calls, etc. But if an operator forgets to add an ingredient or adds it twice, it can produce a quality issue (e.g., off-flavor or color), which hopefully will be picked up by the lab or a quality assurance person. Failing to achieve the right cook or pasteurization temperature or time can result in not only an off-quality product, but a potentially dangerous one. Failure to do a cleaning step at specified temperature, pH or time can cause a food safety problem as well.

“Utilizing software tools that are S-88 compliant [batching software] is a [method] to ensure consistent batch results,” says Shortridge. “They ensure the various recipes are followed to the letter and allow the identification of a ‘golden batch’ standard. These systems also support CIP operations in the same fashion as general recipes, ensuring the production of safe products.”

Shortridge likes to see “hand-adds” (the manual measuring and addition of ingredients) eliminated as much as possible but realizes getting rid of them is not always technically feasible or economically viable. Where hand-adds are deemed appropriate, the implementation of S-88 batching software is key to ensuring hand-add quantity and timing is monitored, tracked and tied to a particular operator—and if needed—signed off by a supervisor.

Kohrt adds that with batching software installed, a batch cannot be started unless all proper manual entries are made, and the process is held from continuing to the next step unless proper amounts are entered or collected.

Batching software also controls, monitors and historically tracks the recipe being followed, ensuring cooking/baking/pasteurization temperatures and hold times are correct, adds Shortridge. Plus, batching software ensures CIP operations are followed, and the end result meets the food quality and safety requirements of the process.

Batch reporting software, according to Beissel, allows manufacturing teams to review production runs side-by-side as they are being made or against prior runs. Processors can execute real-time reviews along the production process and achieve faster batch releases. Processors can also trend CCPs, such as baking temperature, and the system notifies the operator at every step to make challenge testing easier in the case of hand-adds. In short, batching software lets operators address the small issues before they escalate into bigger problems.

Integrating process control with other systems

Due to the complexity of an enterprise’s product lifecycle management, manufacturing and regulatory requirements, integrating complex testing, production, scheduling and other plant floor systems, integrating these systems provides a myriad of benefits to mid-sized and large food and consumer packaged goods companies, according to Chris Jones, vice president of consulting at Junction Solutions.

Most notably, an end-to-end systems’ integration reduces error-prone, time-consuming manual entry and data rekeying by bringing complex, diagnostic data from the LIMS directly into the ERP system at the lot/batch level. This significantly enhances the accuracy of information and reduces “time to output” of data critical for traceability and food safety at the industry, local and federal levels.

“Following the same principle, the same is true for MES,” says Jones. “By seamlessly integrating the ERP and MES systems, an organization has relevant, real-time and actionable information throughout the entire scheduling and production process.” Activities involving the management of temperature, pressure, run-times, etc. can be optimized, and course corrections rapidly implemented should the need arise. Access to this information at the product lot level minimizes the time and scope of recall trace initiatives, which can be extremely cost and labor intensive and impact customer and consumer brand confidence, adds Jones. 

For more information:

Evan Miller, Hertzler Systems, 574-533-0571, ext. 211, ejmiller@hertzler.com

Jim Shortridge, SSOE Group, 419-255-3830, jshortridge@ssoe.com

Chris Farver, Heat and Control, 469-464-2700, chrisf@heatandcontrol.com

Katie Beissel, GE Intelligent Platforms, 800-433-2682, katie.beissel@ge.com

Mike Gay, Rockwell Automation, 414-382-2000; mdgay@ra.rockwell.com

Gary Kohrt, Iconics, 508-216-1238, garyk@iconics.com

Kevin Frantz, Stellar Automation, 904-260-2900, kfrantz@stellar.net

Chris Jones, Junction Solutions, 314-475-3500, cjones@junctionsolutions.com

Mike Edgett, Infor, 646-336-1700, mike.edgett@infor.com

Pat Graham, CAT², 501-328-9178, pat.graham@catsquared.com

Robert McGreevy, Invensys Operations Management, 949-727-3200, rob.mcgreevy@invensys.com

References:

1. A. Coskun Dalgiç, Hasan Vardin and K. Bülent Belibagli (2011), “Improvement of Food Safety and Quality by Statistical Process Control (SPC) in Food Processing Systems: A Case Study of Traditional Sucuk (Sausage) Processing, Quality Control of Herbal Medicines and Related Areas,” Prof. Yukihiro Shoyama (Ed.), ISBN: 978-953-307-682-9, InTech, Available from: http://www.intechopen.com/books/quality-control-of-herbal-medicinesand-related-areas/improvement-of-food-safety-and-quality-by-statistical-process-control-spc-in-foodprocessing-systems
2. Grig, Nigel P. (1997), “Statistical process control in UK food production: an overview,” International Journal of Quality & Reliability Management, Vol. 15, No. 2, 1998; MCB University Press.
3. Linton, Richard H., “Controlling Food Safety Using the HACCP Approach and Prerequisite Programs,” Food Safety Issues, FS-13-W, 2/2001; Purdue University.