Posts Tagged ‘critical limits’

Food Manufacturing Challenges – HACCP Design Principle No. 7

Sunday, November 27th, 2011
     Ever overdraw on your checking account or max out a credit card?  It’s not hard to do if you’re not keeping track of things.  How can we manage household expenses without some sort of record keeping?

      Away from home, in the business sector, record keeping becomes even more important.  In fact, it’s the very thing covered by HACCP Design Principle No. 7. 

     Principle 7:  Establish record keeping procedures. – This HACCP principle requires that all food manufacturing plants maintain records to show they implemented a HACCP plan, are following all principles, and the plan is working effectively.

     Let’s look at an example.  In keeping with the directive of HACCP Design Principle 7, the engineering department of a food manufacturing plant must keep records for each design project.  The design record for a new cookie forming machine would contain things like engineering calculations to determine strength requirements of machine parts and supports, as well as power requirements for the electric motor that drives the machine.  This design record would also contain documentation concerning materials selected to construct the machine, as well as dimensioned mechanical drawings of the machine and its parts.  These dimensioned drawings will show all physical dimensions of the machine and its constituent parts. 

     The record would also contain test results and analysis of the results.  Lastly, the design record must include a risk analysis of potential hazards that could result.  Other activities include identification of CCPs, establishment of critical limits, and other factors in accordance with HACCP Design Principles 1 through 5.  In other words, the record must be complete, bearing witness to an effective adherence to HACCP Design Principles 1 through 5. 

     Principle 7 also encompasses guidelines set in place through Design Principle 6, which calls for the establishment of procedures to govern Principles 1 through 5.  A complete record would contain the procedures themselves, along with any revisions.  It would also contain documentation that the procedures were reviewed and approved by management along the way.

     Finally, of what use would records be if they were incomplete, disorganized, and outdated?  A document control system not only establishes procedures, but assigns responsibilities to personnel within the department for filing design records to make sure that everything is up to snuff.  This system would encompass everything, from the creation of engineering documents, to their timely entry into the record keeping system.

     We have now exhausted our discussion on HACCP Design Principles.  We’ll switch to a new topic next time, examining some basic concepts behind the control of industrial equipment and machinery. 



Food Manufacturing Challenges – HACCP Design Principle No. 6

Sunday, November 20th, 2011
     My daughter’s boy friend stayed for dinner recently and was impressed with our after-dinner cleanup.  He watched as each of us carried out our individual assigned tasks, my wife putting away leftovers and condiments, my daughter rinsing and stacking plates into the dishwasher, and me at the sink hand washing.  To him we seemed a model of efficiency.  It didn’t take long to return the kitchen to its usual state of pristine evening cleanliness.  “Our kitchen is always a mess,” he complained, “probably because we’re so disorganized.”

     You can imagine what would happen if a food manufacturing plant operated like a disorganized household kitchen.  Although employees may know they are responsible for delivering safe products to consumers, without the right procedures in place an unsafe chaotic mess may result.  To get everyone moving in the right direction we look to guidelines established in HACCP Design Principle No. 6.

     Principle 6:  Establish procedures for ensuring the HACCP system is working as intended. –   In large part this Principle acts as a report card.  It follows up on the guidelines established in Principles l through 5, organizing activities into written procedures. 

     For example, design engineers must routinely analyze important identified stages within a design project, then write procedures, that is, a step-by-step instruction guide, which encompasses them.  In this way personnel involved in the design process make best use of the safeguards put in place by HACCP Design Principles 1 through 5.  These steps include things like preparing design proposals, analyzing risks and hazards, creating preliminary designs, conducting design reviews, building prototype equipment and tooling, running tests, collecting test data, and analyzing test results.  For each step, responsibilities of key individuals involved must be clearly defined and sequentially ordered.

     But writing department procedures is only part of Principle 6.  Procedures are no good if they’re just thrown into a file cabinet and no one ever looks at them.  What good are guidelines without a full understanding of how to use them?  Training may be necessary, and management must decide what form that educational process takes to be most effective.   

     Engineering management must verify that established procedures are adequate to the task.  This typically involves taking a hard look at finished design projects and checking critical factors.  Was an adequate risk analysis performed?  Were sufficient critical control points established and critical limits monitored for effectiveness? 

     Next time we’ll wrap up our discussion on HACCP Design Principles by examining No. 7.  It’s the last of the Principles and it’s concerned with establishing record keeping procedures.



Food Manufacturing Challenges – HACCP Design Principle No. 4

Sunday, November 6th, 2011
     Imagine going on a diet and not having a scale to check your progress, or going to the doctor and not having your temperature taken.  Feedback is important in our daily lives, and industry benefits by it, too.

      Generally speaking, feedback, or monitoring, is a tool that provides relevant information on a timely basis as to whether things are working as they were intended to.   It’s an indispensable tool within the food manufacturing industry.  Without it, entire plants could be erected exposing workers to injury and consumers to bacteria-laden products.  It’s just plain common sense to monitor activities all along the way, starting with the design process.  Now let’s see how monitoring is applied in HACCP Design Principle No. 4.

     Principle 4:  Establish critical control point monitoring requirements. – Monitoring activities are necessary to ensure that the critical limits established at each critical control point (CCP) established under Principle 3 discussed last week are working as intended.  In other words, if the engineer identifies significant risks in the design of a piece of food processing equipment and establishes critical limits at CCPs to eliminate the risk, then the CCPs must be monitored to see if the risk has actually been eliminated.

     Monitoring can and should be performed in food manufacturing plants by a variety of personnel, including design engineers, the manager of the engineering department, production line workers, maintenance workers, and quality control inspectors.  For example, engineering department procedures in a food manufacturing plant should require the engineering manager to monitor CCPs established by the staff during the design of food processing equipment and production lines.  Monitoring would include reviewing the design engineer’s plans, checking things like assumptions made concerning processes, calculations, material selections, and proposed physical dimensions.

     In short, monitoring should be a part of nearly every process, starting with the review of design documents, mechanical and electrical drawings, validation test data for machine prototypes, and technical specifications for mechanical and electrical components.  This monitoring would be conducted by the engineering manager during all phases of the design process and before the finished equipment is turned over to the production department to start production. 

     To illustrate, suppose the engineering manager is reviewing the logic in a programmable controller for a cooker on a production line.  She discovers a problem with the lower critical limits established by her engineer at a CCP in the design of a cooker temperature control loop.  You see, the time and temperature in the logic is sufficient to thoroughly cook smaller cuts of meat in most of the products that will be made on the line, however the larger cuts will be undercooked.  The time and temperature settings within the logic are insufficient to account for the difference.  

     This situation illustrates the fact that monitoring does no good unless feedback is provided with immediacy.  In our example, the design engineer who first established the CCP and the critical limits was not informed in a timely manner of the difference in cooking times that different size meats would require, resulting in the writing of erroneous software logic.  Fortunately, continued monitoring by the engineering manager caught the error, leading her to provide feedback about it to the design engineer, who can then make the necessary corrections to the software.

     Next week we’ll see what design engineers do with the feedback they’ve received, as seen through the eyes of HACCP Principle 5, covering the establishment of corrective actions. 

Food Manufacturing Challenges – HACCP Design Principle No. 3

Sunday, October 30th, 2011
     How do parents make life safer and healthier for their kids?  One of the ways is to  impose limits on things like roaming distance within the neighborhood, curfews, and insisting that you eat your vegetables.  Just common sense, right?  Let’s take a look at some more of it.

     Limits are also necessary within the food manufacturing industry.  Let’s take a look at Hazard Analysis and Critical Control Point (HACCP) Principle No. 3 to see how they’re established and why.

     Principle 3: Establish critical limits for each critical control point. – You can think of a critical limit as a boundary of safety for each critical control point (CCP).  So how do you determine that boundary of safety?  It’s difficult to generalize, but if you’ve ever watched the TV show Hoarders, you have an excellent example of one that has not only been breeched, but torn asunder.   

     In order to prevent things in the commercial food industry from getting anywhere near Hoarders bad, maximum and minimum values are set in place, representing safeguards to physical, biological, and chemical parameters at play within the industry.  Critical limits can be obtained from regulatory standards and guidelines, scientific literature, experimental studies, as well as information provided by consultants.  These critical limits come into play with issues as varied as machine design, raw material temperatures, and overall safe processing times.

     How could the hoarders let things get so bad?  If you listen carefully, you’ll hear bits of information that provide a clue.  They’ll say it started with a few things falling to the floor which they didn’t feel like picking up and it escalated from there. 

     Now all of us live within environments which differ as to their cleanliness, but by and large we live within space where we feel comfortable and consider to be reasonably clean.  We don’t all habitually move stoves and refrigerators to clean, for example.  But if we were so inclined, refrigerators do come with front access panels that are easily removed.  Trouble is the space they provide access to often isn’t large enough to accommodate hands and a vacuum cleaner nozzle comfortably.  You can imagine how frustrating and potentially dangerous it would be to public health to have commercial machinery that provided such limited access for cleaning.    

     To cope with this problem design engineers institute minimum and maximum parameters, such as in the critical limit dimensions of a removable cover.  Their guideline would ensure that enough space is provided so that personnel can fully access all aspects of machinery with tools for cleaning.  That same cover can also have established maximum critical limits, so that dimensions aren’t too large and heavy to be manipulated by hand.  Human nature being what it is, something that is too difficult to remove may be “forgotten” and parts of the machine may never get cleaned.

     Raw meats and many produce can contain hazards like salmonella, E. coli, and other nasty critters that are dangerous to human health.  One of the ways the commercial food industry works to ensure that these contaminants aren’t unleashed on the public is to install programmable control systems into processing machinery that essentially cooks the meat at an established minimum temperature for a minimum amount of time.  Utilizing this type of temperature control in conjunction with an established maximum cooking parameter for temperature and time will virtually eliminate the possibility of overcooked or burnt food products.  When you buy that frozen dinner in most cases it’s completely cooked, but it’s a rarity to find it’s been burned.  

     Another situation in which critical limits are utilized is in the maintenance of machinery, such as when they limit the number of hours a machine can be operated before it is shut down for servicing.

     Next week we’ll move on to Principle No. 4 and see how it establishes monitoring requirements for each CCP.  ____________________________________________