Quality is assured by the tools of inspection, and food and beverage manufacturers are beneficiaries of a steady progression to bring inspection closer to the point of production.
In-line and at-line inspection is a long-running objective in food processing, although higher throughput rates have turned it into more of an imperative than a goal. As production speeds ramp up, lab testing looks more and more like a luxury the industry can ill afford. The rework and scrap created by the time that lab samples flag a problem are a serious drag on optimized production.
Sophisticated rotational viscometers for rheological and texture measurements are built by Brookfield Engineering Laboratories Inc., in Middleboro, Mass. They provide important quality data for both Newtonian and non-Newtonian fluids, the latter of which includes most foods. For example, makers of salad dressings must be mindful of yield stress, the force needed to get the dressing to flow out of a bottle. Quality control must monitor the stress level to avoid producing dressing that either gushes out or refuses to flow.
Robert McGregor, Brookfield's general manager of global marketing and high-end instrument sales, characterizes the firm's benchtop devices as "relatively inexpensive," despite features like an on-board smart phone that "can send messages and tell you when you're out of spec." Identifying the problem with an in-line test would be even better, and the inspection tools for that exist. The cost, however, is multiples higher, "and you need a person to be a champion to promote in-line testing," he observes.
"Computerized benchtop equipment is great for the Rand D lab," allows Bill Hughes, an engineer and founder of Innoquest Inc., Woodstock, Ill., but the time lag between the lab and the loading dock can be too great. Five years ago, he developed a handheld device to quantify the consistency of semi-solid foods that require a quantitative test before they ship. He dubbed it the SpotOn consistometer.
The tool was developed specifically for vegetable shortening and margarine manufactured by Bunge North America, which had exclusive rights to Hughes' consistometer until last year. The device combines manual force with on-board diagnostics: The user plunges a rod into the food material, and the device measures penetration resistance and correlates it with depth and temperature. An infrared depth sensor calculates the probe's speed of penetration, and if the user exerts too much or too little force, a measurement is not recorded. Typically, an operator masters the proper force after five probes, according to Hughes.
Measures of consistency, temperature and depth are displayed on an LED panel connected to the device's microprocessor. Data are recorded and downloadable.
Edible oils and margarine are placed in a hardening room after processing, and when consistency is in spec, pallets are released. Sometimes, there will be an area on the pallet where product is out of spec. Testing with a consistometer identifies where that area is and allows processors to optimize storage time. Ice cream, whipped toppings and specialty dough are among the semi-hard foods Hughes believes could benefit from his inspection tool.
While quality data are essential for process control, inspection hardware often is viewed as a risk-management tool against negative outcomes. When inspection is combined with a value-added function, capital costs are easier to justify. One example is the BioPrint system that Key Technology Inc., Walla, Walla, Wash., recently added to its portfolio.
Key acquired erstwhile competitor Visys NV in February, complementing Key’s belt-fed sorters with the Belgian firm's chute-fed in-air sorters. More importantly, Key acquired advanced laser technology and hyperspectral-based BioPrint capabilities for its technology tool kit. Visys's Cayman chute has a concave shape that turns "a free fall into a controlled fall," explains John Kadinger, Key's marketing manager. By positioning ejector valves closer to the product passing through the chute, there are fewer false rejects, which means yield is increased.