Perfecting purple chip production
“Purple tortilla chips are a first on the market,” says Cindy Kuester, vice president of sales at Axium Foods. “We always say that if you make a great product at a great price, you’ll have customers. We know we’ll have more with Mystic Harvest Purple Corn tortilla chips.”
The deeply hued corn has 25% more antioxidants than blueberries, so is fast approaching classification as a functional food, according to the American Botanical Council. Cross-bred to get such high antioxidant levels, the purple corn also has no trans-fat, preservatives or hydrogenated oils.
But would it work in a tortilla chip? The Axium Foods team collectively held its breath and dove head-first into developing a tortilla chip with it and tweaked its processes. The results are tortilla chip snacks in Authentic with Sea Salt and Multi-Grain varieties. Axium Foods has exclusive rights to the use of purple corn for tortilla chips.
The company makes the chips on one of seven production lines at the South Beloit plant. It has two lines that run all of its tortilla chip products and one for corn chips. Another line runs caramel corn, one runs crunchy cheese curls, one runs puffed cheese curls and the seventh runs party mix.
“We have to be flexible producing all of our snacks,” says John Murphy, vice president of operations. “We run close to 150 different stock-keeping units each week. Production has to be consistent. One of our main benchmarks is a favorable experience and product consistency is one of the keys to that.”
To keep pace with the huge growth of the private-label products it has seen in the last three years, Axium Foods has to indeed be agile. The company has grown so much that it had to move its warehousing functions two miles down the street to a new 30,000-sq.-ft. distribution center. “The DC has allowed us to expand our process capacities,” says president Jerry Stokely. “We also added two production lines in the last few years, so we’ve had some growing pains.”
A stable workforce and sophisticated, computer-controlled production processes help. These are things Murphy says the production department relies on every day. “We also depend on [trustworthy] process controls,” he adds. “Our in-house control engineers help us maintain our closed-loop control systems on the production floor. We use computerization to help drive our equipment and programs and have eliminated some of the human interaction.”
Producing purple chips
Different processes are spread throughout the facility. Mixing is in one area, baking is in another. Many of the equipment and ingredient suppliers are local.
The production facility runs three shifts a day, five or six days a week, depending on its schedules. Churning out about 3,000 lb. of tortilla chips an hour, the processing equipment must be very versatile and flexible to accommodate all of the needs of private-label and copack customers, Murphy explains. “We don’t run something once a month and are done with it. We make routine line changeovers all the time, so our equipment has to keep up. We adapt to the needs of our customers.”
Production of Mystic Harvest purple tortilla chips begins as raw ingredients are pumped into the processing area. Three different types of bulk corn used to produce the snacks are pumped in from one of six 100,000- to 150,000-lb. silos outside. The silos hold white, yellow, blue and now a purple corn. “All of our equipment is programmable-logic-controlled,” Murphy points out. “And there are metal detectors and x-ray systems on every line.”
The purple corn is scaled and mixed with lime and water before it’s cooked in 2,000-lb. batches. The kettle cookers only take four minutes to cook the corn at 195-200 deg F. Next, the corn is transferred to a set of vertical soaking tanks where it steeps for about 12 hours. “The lime acts as a processing aid and also penetrates through the corn,” explains Murphy. “Along with the water, it breaks down the starches and the hulls and also helps extend shelf life [for most products, that’s between 16 and 18 weeks]. We also add fiber to our tortilla chips to give them more strength and rigidity, though it doesn’t affect the flavor.”
Soaking, cooking, milling
The corn is also aerated, which creates froth on the top of the vats. “We aerate the corn so that it doesn’t sink to the bottom of the vat and stays static,” Murphy adds. Cold water can be added to continue cooling the corn and bring the temperature to about 130 deg. F. Then the corn is washed and drained and and transferred to the hopper of a mill to be ground into dough. Later, the dough is pumped into a sheeter where two sheeter rollers reduce the dough to a certain thickness before forming and cutting it into chip shapes.
As the chip shapes emerge on a belt conveyor, oil can be added to give them strength and rigidity and reduce breakage. The chips then head into a three-pass oven to be baked for 20 seconds at temperatures of about 770 deg. F. The super-hot oven dries the chips, enhancing their alkaline flavor. “They aren’t yet crispy at this point, but they’re not dough anymore,” says Murphy.
The baked chips emerge from the oven and travel onto a wide incline belt, progressing through a series of cooling racks and passing a sensing system that checks their temperature. As they travel and cool, the chips dry a bit more and make a 90-deg. turn up an incline belt before they enter a fryer that measures about 30 ft. long. Particles accumulate on stainless-steel panels and the chips enter the fryer system.
A thermal-intensive process
“We had to add one of the tortilla lines a few years ago because we’ve been growing so much,” Murphy recalls. The chips fry in an oil bath at temperatures of about 375 deg. for 1 minute, 15 seconds. A paddle wheel pushes the chips through the system while a fines filter removes any particulate that sinks. Next, the fried chips emerge and eject onto another incline conveyor that carries them up to the plant’s mezzanine level.
While the chips are still hot, they move onto a vibratory conveyor to spread out before salt and seasonings are added using tumblers and salt sprays. Oil and moisture content are again checked at one of several Hazard Analysis Critical Control Points (HACCP) on the line, Murphy explains.
“We regularly look at the product itself, rely on process sensors and test the chips for salt, taste, visuals, oil and quantity. We also check the bag seals and have someone evaluating the packaging quality, so inspections are a constant function on all of our production lines,” he says.
In addition, a sample of the chips is taken and measured against lab data. The lab is just off to one side of the production floor. There, finished goods and raw materials tests are conducted. “We look at ingredient attributes, microbial counts, moisture, salts, attributes of the corn, corn grading and check for consistency,” Murphy explains.
“We use calibration protocols regularly to make sure our equipment is running properly and also sample against our lab data to ensure we’re not deviating from the standard,” he adds. “The lab personnel also test ingredients and finished products. Ours is a very thermal-intensive process, with chips going through temperatures of 770 and then nearly 400 deg. F, so there are few bacteriological risks. The only thing that could change this perspective may be the seasonings, but they have to pass microbiological inspections before they are ever shipped to us or are received here.”
After seasoning, the purple chips are deposited onto a set of eight multi-bucket weigh scales above a form/fill/seal bagging area. As the Mystic Harvest purple chips move onto the buckets, they’re weighed and drop down through the chute of a vertical form/fill/seal bagger. The bag film unwinds through the system, it’s ink-jet-coded with pertinent product information and the 7-oz. bag is bottom-sealed. The chips fall into the bags, passing a metal detector on the way. Next, the bags are top-sealed and exit the system. The finished bags then head into a robotic case-packing system that uses vacuum grippers to place them, two at a time, into preprinted shipping cases at 55 bags per minute. The system incorporates an automatic case erector and will soon be upgraded with an automatic seal checker, Murphy tells SF&WB. The eye-catching, preprinted corrugated shipping cases are ink-jet-coded with product identification data as they exit the packing sequence.
Centralized sealing, palletizing
“The tops of the cases are left open so that the system can check the bags for air that might be escaping,” he explains. “They use a laser to check the height of the bag. If the height deviates from the preset requirements, then air is escaping. As we continue to grow, we will add more case packers like these because we have more room to expand.” Quickly, the open-topped cases proceed further into a 10,000-sq.-ft. shipping and receiving area, which includes centralized palletizing. They’re sealed on a pair of continuous-motion random case tapers before they pass through an x-ray system that checks them for contaminants.
All of the products go through a centralized palletizing area. Murphy says this is a section of the line that’s very flexible. “We have equipment here that can deal with many different packages and package sizes,” he says. “Bag sizes range from 1.5 to 18 oz., and we also make club packs. We’re heading into a direction where we need high-speed equipment that can accommodate all sorts of primary and secondary container sizes, heights and configurations.”
Currently, palletizing of the cases is manual, but Axium Foods hopes to automate it soon. “We know we want more automation there,” he explains. “We are in the early stages of implementing an enterprise resource planning (ERP) system, which will provide more communication and data accessibility. We will be able to tie the ERP into a robotic palletizing system to help build loads. So once the ERP is up and running, we’ll look automatic palletizing or robotic palletizing equipment.”
Through all of these equipment advances, Murphy says line workers are repositioned to handle other growing needs and functions within the organization. “We haven’t laid anyone off,” he points out.
Line operators then stretch wrap the loads and stack them in the shipping/receiving area two-high before trucking them over to the DC down the street. This transport occurs at least once an hour.
Repurposing its food waste and recycling are important to Axium Foods, Murphy says. Food waste is brought to cattle farmers. “We don’t have a lot of things going to landfills.”
Stokely adds that Axium Foods has recycled its plastics and paperboard waste for years and has its own wastewater treatment facility that uses anaerobic digesters. “We treat all of the waste to where it’s essentially drinking-water quality,” he says. “We’re also experimenting with a methodology to prescreen some of our wastewater using a natural ingredient that can remove solids. By processing that byproduct, we may be able to create a natural-type fertilizer and pesticide.”
The company says it plans to continue developing the new Mystic Harvest tortilla chips product line with additional flavors, handsome packaging, product customization and new varieties.
Expanding distribution is also an important goal. “We’ll definitely be automating our production further,” Stokely adds. “We have begun using some robotic case packing on some of the lines and will continue on that path as much as is practical. We’ll evaluate several new things.”
Stokely says that Axium always has a focus on the future. “We’ve seen double-digit growth recently, so we hope to expand on that. What else is down the road? We may very well be looking at new facilities. But we will also certainly continue to work with customers to understand their needs and how we can best meet those needs. Our company has not only been stable but it’s a thriving entity, and that’s quite rewarding, so we’ll continue to set new standards for ourselves.”