Dispensing flavors accurately
July 1, 2012
by Shane Whitaker
Without topical seasonings, the blandness of most snack foods and crackers would make them as popular with consumers as fleas at a dog show. Therefore, snack processors apply flavors and salt, but they also adapt to a market that wants snacks with lower sodium and fat levels but all the flavor of the original varieties.
Good taste, of course, attracts repeat purchases, but mouthfeel and visual appeal also are important. Seasonings and flavorings play a major role in all these attributes.
“Consumers look for natural flavors and, in the higher value snacks, artisan-type quality,” said Dave Homeyer, president of Spray Dynamics, St. Clair, MO, a Heat and Control company. Consequently, he surmised, processors want to achieve the highest-quality products at the lowest possible operational cost.
Snack manufacturers also continue to explore more exotic flavors. “We are involved with projects to apply a much wider variety of ingredients to crackers, potato chips, pretzels, tortilla chips and other snack foods than we’ve seen previously,” said Ty Sarajian, president, Axis Automation, Hartland, WI. “Customers are exploring a wider range of ethnic seasonings and flavor intensity.”
Reducing operational costs
To meet this expanding demand for exotic flavors, equipment manufacturers offer on-machine seasoning systems and small production lines with quick flavor changes, according to David Woollard, group seasoning sales, TNA Australia Pty Ltd., parent company of TNA North America, Coppell, TX.
On-machine seasoning — application of seasoning at the point of packaging — greatly improved production uptime by reducing cleaning for flavor changes, noted Blake Svejkovsky, product manager, Heat and Control, Inc., Dallas, TX. In fact, these systems save processors hours per week and, in many cases, whole shifts of production. “We see this trend continuing as more and more food safety and allergen criteria challenges are placed on the marketplace while consumer desires for more and more flavor choices continue to expand,” he added.
Manufacturers producing some of the largest brands in the industry have reduced operational costs by 15% and even more, in some cases, using Heat and Control’s Revolution on-machine seasoning technology, Mr. Svejkovsky observed. “This method is really a full system approach incorporating the latest in proportional gate and feed technology with advanced FastBack Revolution seasoning application,” he said. “It’s all tied directly to the Ishida weighers and bagmakers to provide a comprehensive system and a smooth running line.”
TNA’s seasoning systems are based on simplicity, according to Mr. Woollard. “Our tumble drums create a continuous flow of product, continuous oil spray and continuous seasoning application all controlled by continuous weight measurement of the product flow into the drum,” he said. “Feedback control loops ensure that these systems work together and provide a historical record of the application achieved at any time.”
TNA recently introduced its intelli-flav OMS 3c, a complete, 1-piece solution for applying both wet and dry seasoning and flavoring at throughput rates up to 1,200 lb per hour for a variety of applications. The unit features two high-precision continuous spray guns, delivered by a closed-loop system to ensure accuracy.
Snack producers want greater accuracy when dispensing ingredients because of seasoning costs and the desired flavor profiles. Axis enhanced the precision of both its volumetric and gravimetric feeders and, in some cases, combined the two technologies, according to Norm Searle, the company’s COO.
“For drum seasoning applicators, the two biggest issues we’ve had to address are better delivery of seasonings and rapid changeover of ingredients,” he added. “In older systems, uneven distribution of seasonings in the drum was a major problem. This was further complicated by ingredients with higher moisture content and, thus, poor flow characteristics.”
In response to customer demands for efficient seasoning use, Axis designed a different ingredient delivery system that allows for excellent coverage while maintaining the proper ratios, according to Mr. Searle. “Better coverage also leads to less breakage because the product spends less time in the drum,” he added.
Omega pocketed-roll dispensers from Reading Bakery Systems, Robesonia, PA, apply salt to pretzels prior to baking as well as toppings to a variety of other snacks, crackers and baked goods. The company introduced the pocketed roll to provide a more even coverage, thus helping manufacturers meet nutritional labeling laws, noted John Eshelman, Reading’s director of snack and pretzel machinery sales.
The company built these dispensers to accurately dispense across lines stretching 84 in. wide. These units generally feature reclaim units with vacuum transport, and Reading recently added powered sieves to control dust in the reclaim and transport system.
Snack manufacturers also are using flavored oils to create more authentic tastes while also accomplishing low-fat and low-salt applications, according to Mr. Woollard, who added that authentic tastes imply a healthier product to the consumer.
Processors also desire spray application of liquids other than oils and fats to aid seasoning adhesion. “Lower oil application demands more accurate and consistent spray systems,” Mr. Woollard added.
Because snack manufacturers are using more seasoning- and flavor-infused oils, Axis redesigned delivery methods as well as the geometry inside the spray chambers, according to Mr. Sarajian, noting that standard spray delivery systems and heads cannot be used because of their tendency to clog.
“To maintain consistent and reliable application requires special pumps, spray heads, a recirculating cycle to keep seasoning from settling, and slurry makeup agitation to keep seasoning in suspension,” he said. “In addition, advances to both the jacketing system and chamber geometry have addressed issues with keeping the slurry at a more constant temperature and avoiding drips.”
Achieving uniform coverage
Snack manufacturers are extremely concerned with obtaining consistently uniform coverage and tight application rates. “Our engineers work closely with the seasoning suppliers to adapt our equipment for optimal application of today’s seasonings,” Mr. Homeyer said.
“We use many technologies depending on the product and coating requirements,” Mr. Homeyer continued. “These systems include slurry sprayers, centrifugal coaters and our side-vented coater dryer, which is used with water-based coatings. Our centrifugal coater is used with smaller products, such as sunflower seeds and snack mixes, to add both oil and dry flavorings. This produces a very even coating, and because this is an automated batch system, it provides very accurate application rates.”
Weighback measuring technology from Heat and Control provides the most accurate non-belt weighing system available for accuracy in measuring and dosing accuracy, according to Mr. Svejkovsky, who also touted the system as easy to clean and low maintenance.
Today’s seasonings also contain fewer flow enhancers, according to Mr. Homeyer; therefore, Spray Dynamics engineered its machines to overcome the flavoring’s natural cohesiveness. “We use special polishing techniques to reduce seasoning friction and to maintain a consistent flow of seasonings to the metering auger,” he said.
Additionally, Heat and Control/Spray Dynamics offers flexible and directionally polished stainless steel hoppers to eliminate bridging. Its Excaliber and Scarf Plate seasoning applicators are engineered to provide equal distribution across particle size and density, Mr. Homeyer added.
The growth of artisan-style products presents another test to manufacturers as these seasonings often have particles of different sizes and densities.
“The challenge is to not separate these particles and convey all at the same rate,” he said. “Our centrifugal coaters evenly disperse multi-density seasonings of this type in both dry and oil-added varieties.”
With oil slurries, the company relies on mixing and fluid velocity to keep the particles suspended, and for dry powders and particulates, it uses the scarf feeder with weirs to maintain a consistent curtain, he explained.
Axis Automation developed different methods of hopper agitation, feeding and dispensing to address issues with blends of ingredients at dissimilar densities while maintaining a homogenous blend, Mr. Searle explained.
Protecting product integrity
Tumble drums from TNA use soft flight technology and multiple small flights to tumble the products rather than lifting and dropping the product. “This tumbling action tends to create a continuous waterfall of product that presents the product consistently and evenly to the application of spray or seasoning,” Mr. Woollard said.
To minimize product breakage, Heat and Control used high-speed cameras to assist with designing its special tumble drum profiles, lengths and velocities, Mr. Svejkovsky said. Additionally, its FastBack seasoning and coating system simultaneously conveys and tumbles the product on a pure horizontal plane using gentle horizontal-motion conveying.
“This accomplishes two things,” he added. “First and foremost, it reduces dwell time variation caused by changing product flows inherent with gravity-fed tumble drums. Second, it allows product to be conveyed without tumbling when no seasoning is being applied.”
To protect snacks, Mr. Homeyer said, Spray Dynamics engineers look at each customer’s product uniquely and determine the proper flight design and size of the coating drum based on several physical characteristics.
New flavor varieties are constantly being launched in the snack aisle, and today’s systems allow for more even coverage and less product breakage when applying seasonings to snacks and crackers.