From Lab to Line
May 2, 2011
by Laurie Gorton
Bakery formulations call for many ingredients with diverse parameters. But flour tops the list, and it can vary year to year according to growth and harvest conditions. So it’s not surprising that specialized instruments have developed to characterize flour’s performance.
“Flour quality control is not an easy task,” said Charles Loubersac d’Hotel, export sales manager, Chopin Technologies SAS, Villeneuve-la-Garenne Cedex, France. “Many parameters have an influence, starting with the protein, the starch, the enzymes and many other components.”
Some of these units are unique to the milling and baking laboratory, while others have wide applications in the food, chemical and pharmaceutical industries. But all have been touched — and improved — by advances in electronic controls and software and made more robust with beefed-up motors and enhanced sampling systems.
“The high-speed and high-torque capabilities [of new instrument designs] provide analysis capabilities of new food products that could not be analyzed before,” said Wes Shadow, business development manager, Perten Instruments, Inc., Springfield, IL.
Rugged construction makes several of these new instruments suitable for at-line use in plants. “While the Farinograph-AT is engineered for R&D applications, it is quite rugged enough to withstand daily use,” explained Michael DiNatale, marketing manager, C.W. Brabender Instruments, Inc., South Hackensack, NJ. “It can be used at-line in the plant to test dough taken directly from the production line for quality control.”
Preparation and handling of samples has improved greatly. Many manual processes depend on glassware and are very labor-intensive. For example, measuring nitrogen (a marker of protein content) previously required the difficult, time-consuming, wet-chemistry Kjeldahl method. Today, it can be done by the Dumas method of quantitative combustion digestion. Wrap the 1-g sample in foil, insert it in the elementar Rapid N Cube, cue the high-temperature (900°C, 1,652°F) combustion process, and get the reading in just a few minutes. Elimination of caustic materials provides environmental and employee safety advantages, too.
Automatically sequencing crucial steps improves the accuracy of readings. Mr. DiNatale noted that the automatic water dosing system of the new model Farinograph-AT reduces operator error during addition of water to the flour in the mixer measuring head.
Faster results mean quicker decisions about dough ingredients. “A pending AACC method with the Perten doughLAB reduces analysis time from 20 minutes to just nine,” said Mr. Shadow. The instrument is a dough rheometer capable of varying temperature and energy inputs to mimic commercial mixing. It determines water absorption, dough mixing profile, development time and stability for doughs made with wheat, rye and durum flours. It can test finished dough right out of the mixer or proofing room.
Time and resource savings apply to measuring finished product characteristics, too. Handheld color meters take the subjectivity out of judging color, the first perception used by customers in purchasing goods. “Simple, easy-to-use color meters eliminate the need for comparing a product color to a visual standard, which were once common,” said Lou Carulli, marketing manager, Konica Minolta Sensing Americas, Ramsey, NJ. “For more experienced users, optional software can keep historic data and further analyze results, making the color meter the perfect tool for lab and production staff alike.”
Good volume is a mark of quality for many baked foods, and it’s a necessary aspect of consistent performance. But variety products, including artisan-inspired items, challenge seed displacement methods, the traditional way for determining volume. When electronic scanning is applied, full 3D results are possible, even for light-textured and delicate products. “With the Volscan Profiler, bakers can control production more rigorously and rapidly eliminate inconsistency, resulting in greater consumer satisfaction and increased profitability,” observed Jo Smewing, applications manager, Stable Micro Systems, Godalming, Surrey, UK. (The Volscan is marketed in the US by Texture Technologies Corp., Scarsdale, NY.) The noncontact assessment of volume is ready in fewer than 60 seconds, and the 3D digitization can be viewed with rotation in all planes and archived for further analysis.
Going deeper into texture, units such as the Brookfield CT3 texture analyzer have been adapted for the mill and bakery environment. “The CT3’s success in commercial baking is due to its high resistance to dust intrusion, eliminating the need for frequent maintenance,” said Kathy Durant, marketing/media assistant, Brookfield Engineering Laboratories, Inc., Middleboro, MA. “And its low price allows this technology to be used in areas not traditionally set up with such analytical equipment. Texture profile analysis is built into the CT3; no computer is required.”
Wireless technology, new to this field, enables better communications between instrument and technician. For example, the ANKOM RF gas production system measures yeast activity, remotely captures pressure and temperature data and stores it on a PC for data analysis. “Automatic graphing capability within the PC software allows the user to quickly see what is happening at any point during a study,” said Greg Coutant, strategic marketing director, ANKOM Technology, Macedon, NY. The system handles up to 50 wireless modules located anywhere within the radio frequency distance to simultaneously run multiple samples in various environments while minimizing bench space and cost.
Far and away the most critical application for lab instruments is to identify flour’s functional and baking characteristics, performance in doughs and chemical profile. Chopin developed its Profiler based on the company’s Mixolab to offer a matrix of six axes, numerically ranked 0 to 9, each representing a different quality index: absorption, mixing, gluten quality, viscosity, amylase and retrogradation. “The flour tested is identified on these indexes, which becomes its fingerprint,” Mr. Loubersac d’Hotel explained. Using this profile, or fingerprint, the baker can test flour and know immediately whether it is in or out of specification. “This one single test allows bakers to gain better understanding, avoid troubleshooting and communicate precisely with suppliers,” he said.
Because they need only small quantities of materials, these newer instruments are finding use for early analysis of samples in wheat breeding studies, according to Mr. Shadow, who described this use of the Perten RVA 4500 rapid visco analyzer. “It allows testing of many different products and parameters, including new formulations, blends, varieties and ingredients,” he added.
Besides fingerprinting flour, quality labs must also characterize the full range of bakery ingredients. The instruments address everyday targets such as dough consistency, while others manage R&D goals that encompass new ingredient testing — even testing of new wheat breeds, according to Mr. Shadow.
“Automated determination of total dietary fiber (TDF) will soon be a reality,” Mr. Coutant said. The company has been developing and designing an automated instrument for TDF for about four years, a system about to receive its market launch. To date, determining soluble and insoluble dietary fiber content has been a long, multistep, manual process. The TDF system he described automates the AOAC 991.43 method using filter bag technology under computer control. The result lower labor costs and less opportunity for error because there’s no need for manual transfer of materials between containers.
The intended function of many instruments specialized to the milling and baking industries is to give the lab results that are as close as possible to what happens during the actual bakery processes. Mr. Loubersac d’Hotel compared the Chopin Mixolab to general-application rheological instruments and said, “Most [other approaches] focus on the gluten alone, with few considering the starch. The water absorption you obtain with common rheological methods doesn’t translate precisely into actual absorption in an industrial mixer. We measure consistency of a dough — a real dough, not a slurry or batter.” He explained that in the presence of limited water, gluten quality influences starch behavior.
Near infrared (NIR) technologies continue to make inroads. A new inline NIR-based system monitors flour, powdered ingredients and even whole grains as they move through the processing system. The ProFoss system uses an NIR analyzer mounted directly in the miller’s production piping to check flour flowing at up to 25 m (82 ft) per second. Measurements can be made every few seconds, rather than taking samples back to a lab, according to Richard Mills, journalist, marketing and communications support, Foss, Hillerød, Denmark.
Easy sample preparation and calibration characterize the Brabender Kernelyzer-F, an NIR instrument that Marion Klee, marketing, Brabender Gmbh & Co., Duisburg, Germany, described as suitable for both lab and at-line production use. “Just put the sample in the sampling cup, place it on top of the instrument’s rotating sample tray and start the analysis,” she said. The unit features preset calibrations and software that allows users to adjust and create calibrations for their own operation.
Quantifying quality, which can be a vague concept, requires precise analytical rigor. That’s where lab instruments can make a difference. “In a world where customers’ requirements are moving fast, new product development is a critical competitive point for industrial bakers,” Mr. Loubersac d’Hotel observed. Especially with trends such as gluten free, high fiber, whole grain and fortification, “their tools must help assess not only quality but also functionality.” In other words, instruments used in the lab must yield results translatable to the line. Read More on the Subject: Online Exclusive: Instrumentation Tech Showcase