Advances in inspection technology typically migrate to food and beverage from other industries, but in the case of near-infrared (NIR) spectroscopy, consumer electronics may bring the next breakthrough.
It wouldn’t be the first time. Computer gaming laid the groundwork for simulation models that take the guesswork out of process changes and construction projects. In the case of NIR, a miniaturized spectrometer for soil analysis in agriculture likely will be integrated into in-line inspection systems within a year, thanks to price reductions made possible by smart phones.
Benchtop spectrometers costing six figures now are complemented by portable units costing five figures for material quantification. Various wavelengths in the electromagnetic spectrum can be used, but the NIR region offers several advantages, including deeper penetration into a sample than mid-infrared light waves. Accuracy in parts per million feedback may not be as great, but it is precise enough to find a home in process analytic technology used in pharmaceutical production.
As costs have declined, multinational food companies such as Nestle, McCormick, Kraft and Cargill have deployed NIR spectrometers. Applications include monitoring moisture content in coffee beans, brix in orange juice and fat and moisture levels in meat. A spectrometer system from tec5USA, Plainview, N.Y., can penetrate an apple with a beam of light to detect rot or a hollow interior.
Miniaturization of hardware has played a prominent role in affordability for spectrometry. Room-sized systems gave way to benchtop spectrometers and then briefcase-sized units that can be attached to blenders and other equipment. Besides the software and processors that analyze reflected or absorbed light to determine a material’s composition, the spectrometer itself includes a light source, mirrors, a laser, beam splitter and interferometer, where spectral encoding occurs.
Miniaturization is taking a giant leap forward. Using semiconductor-style wafers and etching techniques that put movable mirrors and other components on a chip, three firms – Cairo, Egypt-based Si-Ware Systems, Spectral Engines Oy in Finland, and Consumer Physics in Tel Aviv, Israel – have shrunk a functioning spectrometer to the size of a TicTac box. The units are integrated into some industrial instrumentation already, but the developers are focusing on smart phone manufacturers to integrate their NIR spectral sensors, either as an attached component or built into the phone itself.
Besides giving consumers the ability to scan produce and other food to identify the presence or absence of specific components, such as allergens, those sensors would have to be mass produced, driving costs well below $100.
“Using semiconductor components for Fourier-Transform NIR spectroscopy, we’re able to provide a dramatically smaller and dramatically lower-priced spectrometer,” says Scott Smyses, executive vice president-worldwide marketing & business development at Si-Ware (www.si-ware.com), which has offices in the Los Angeles area. The electronics, photo detector and chip packed into Si-Ware’s sensor generates raw data that must be analyzed, which is why the firm is in discussions with instrumentation companies that already provide NIR systems for in-line, nondestructive inspection of food and other materials.
Si-Ware’s first generation MEMS (micro electrical mechanical system) chip measured 10x10mm, but it has been replaced by an even smaller chip that can be manufactured for $100 in volume. The next generation will be nano-scale, Smyses says, with a target price of $5. “The goal is a 6x6mm chip, and that’s being driven by smart phone technology,” he adds. “That would enable us to sell millions.”
The automation vision
NIR sensors already are justifying their cost in food plants; one vendor reports that a customer realized a payback in less than two months for a system that flagged product with water content below the targeted threshold, allowing the processor to boost yield. But unless a feedback loop enables automatic adjustment upstream to correct product drift, human reaction is required.
Not so with vision-based sortation systems. Some of the industry’s most automated processing facilities handle potatoes, nuts, berries and citrus products. Vision systems replaced most eyes decades ago for grading and foreign-material identification. As those systems have advanced, robotics and digital sortation equipment have largely replaced people in some operations.
Clementines are an example. In recent years, Fowler Packing Co. and Paramount Citrus Packing Co., suppliers of virtually all bagged clementines sold in North America, have built highly automated packing houses. Graders from New Zealand-based Compac perform visual and density inspection at both Fowler’s Fresno, Calif., facility, which processes 450,000 bags a day, and at Paramount’s Delano, Calif., plant, which opened in 2012 and represented a $200 million investment by Roll Global.