By Lauren R. Hartman
Founded by bun-lovin’ Cordia Harrington, Tennessee Bun Co. (TBC) is a $50-million conglomerate with sales and marketing strategies that revolve around best serving its customers. That’s why its production departments have to be nimble.
“We have tried to make our facilities very flexible so that we can provide a one-stop shop, so that we can serve all of their needs,” says Harrington, the founder, president and CEO of the ever-expanding Nashville, Tenn.-based business.
In fact, sales growth of the tasty hamburger buns and rolls prompted the company to establish Nashville Bun Co. (NBC) in 1999. NBC originally served as a packaging facility to handle the fast growth of its parent, TBC. But with baking demands up almost as quickly as a six-inch hoagie roll rises, the packaging facility was soon transformed into a full-service bakery with both an English muffin production line and a hearth line.
Inspected twice annually by the American Institute of Baking (AIB), as well as several other entities, TBC and NBC strive to achieve the highest standards in customer safety, including consistent, top inspection scores. The companies are Hazard Analysis and Critical Control Point (HACCP)-certified and the shared, main production plant was built to have some of the fastest high-speed bakery equipment in the world with an output exceeding 1,000 buns per minute.
Spanning 53,000 sq. ft., the TBC/NBC plant in Nashville, Tenn., produces melt-in-your mouth artisan-style breads, rolls, burger buns, hoagies, split rolls, yeast rolls, mini buns and regular size and mini English muffins, all in assorted varieties and configurations.
Today, NBC houses the main production facility, which includes indoor bulk flour storage silos that can store up to 200,000 lb. at a time and produce fresh products with a seven- to 16-day shelf life (frozen products have up to six-month shelf life).
A selection of the product is toasted in a conventional toaster to check for crispness and toasting properties, then rated and inspected. Data is put on spreadsheets to outline possible developing trends, says Clint Adams, plant manager.
“The flow of the plant is like a horseshoe and shipping and receiving are located within the same area,” Adams says.
The operation also produces 50% fresh English muffins and buns and 50% frozen product, he adds.
At the time of Snack Food & Wholesale Bakery’s visit, the two lines were running English muffins and biscuits, the latter of which is outfitted with a hearth oven. The same type of mixing capability is used for rolls/buns and biscuits, but the lines divert to different areas. Along with daily maintenance and sanitation functions, each line is outfitted with a quality control inspection operator and visual inspection systems that check for the proper color, size and shape of each product. Any product that doesn’t meet specifications is rejected.
The plant currently runs three shifts, eight hours a day, six days a week, and has experienced a 50% increase in operating time, from 90 to 135 production hours on one line alone, Adams says.
“Our statistical process control (SPC), weight checks and different quality attributes are computerized,” he explains. “The system automatically inputs that data. We have made other operational improvements, including our largest capital improvement in the last year - the addition of a sheeting line to run the biscuits. We also focus more on training now than we ever have before and conduct meetings every two hours for quality. We also hold monthly quality and safety training that’s attended by all employees. Line operator and maintenance leads also report the status on each of the lines periodically, and the staff determines if there is anything that requires extra monitoring in order to best move forward.”
Mix, Portion and Off to the Griddle
The English muffin line runs at speeds from 1,100 to 1,400 units per hour while the hearth line runs 1,400 dozen to 3,500 dozen biscuits an hour.
On the English muffin line, raw dough starts out with flour, yeast, sugar, butter and other ingredients that are piped into the mixing area and into a mixer in 1,000-lb. batches. The plant dispenses 2,000-lb. totes or bags through a loading station or directly to the mixing process. During mixing, the dough becomes wet and sticky; then transfers from the mixer into a new divider system that increases consistency in the product and reduces weight variations. The dough is automatically piped into a portioner that separates and deposits it into 12-cavity trays.
As the filled trays convey downstream, they travel to a corn meal depositor before the six-lane portioning system divides into a 12-lane configuration of trays that move into the proofer. There, the dough proofs at 110ºF and 30% relative humidity (RH). Mold inhibitors are added at this point. Once proofed, the muffins are deposited into pans that convey into the griddle and bake up to 204ºF for eight to 10 minutes.
“The English muffin griddle can hold up to 2,200 muffins at a time,” Adams explains.
The lines change over at least once a day according to size and variety, which takes approximately 30 minutes, he adds.
Random muffin samples are then selected for weight checks and monitored on a touchscreen weighing system that helps reduce product giveaway and variation, which in turn, helps keep costs down, Adams says.
After the English muffins are baked, they wind their way on “layers of conveyor” into a spiral conveyor to cool at ambient temperatures. Next, the cooled muffins are transferred onto a multilane belt conveyor where they transport single file toward the packaging area. A vision system checks for size, height and color and inspects for contaminants before the muffins head into a slicer to be sliced or forked.
The English muffins then convey through a metal detector for an additional safety/quality check. The line then splits into two lanes that lead to a collator where a manual quality control check takes place.
Depending on customer specifications and package type, the lanes layer the English muffins into groups of six by six, four by four or other desired configurations and quantity before the groups accumulate on a table and are automatically placed in clear bags.
“There are multiple [package] configurations here, but we are currently packing muffins a dozen per bag, or six per coin pack,” Adams says.
With their bags in place, the multipacks are automatically clip-closed and conveyed to a case packing section where they’re manually packed 16 dozen per case.
Compared to English muffins, baking biscuits is hot stuff. The hearth line was added in 2005 and continues to undergo expansion, Adams says. For example, it splits in two but incorporates the same type of dedicated mixing equipment as the English muffin line. It also has a divider and an intermediate proofer arrangement.
Dough for either the biscuits or buns is mixed using the same horizontal mixer, but the bun dough is diverted to either the divider or the sheeting line for biscuits. The new sheeting line was installed this year for straight dough, which requires no proofing or fermenting. After the dough ingredients are mixed, they’re coneveyed overhead either to the divider or the sheeting line, depending on whether they’re going to be biscuits or rolls. Rolls and hamburger buns are sent through a divider.
After mixing, the dough is put through a thickness reducer to achieve the proper scaling weight. Rollers press the dough out to a flatter and thinner consistency. A cutting system then cuts six biscuits across as the line is monitored. Operating procedures are viewable on a touchscreen control system that checks operating speeds and alerts operators to any problems.
After the trim is removed from the cut pieces of dough, the newly formed raw biscuits are dropped onto large baking pans that hold six rows of nine biscuits each. The pans travel several feet for staging to the large hearth oven. Rolls, however, are sent into a spiral proofer prior to baking. The immense oven measures about 60 ft. long and can accommodate six of the large pans across. The biscuits are baked at temperatures ranging from 300-450ºF, through eight different zones in the oven.
After the biscuits emerge from the oven, they are automatically de-panned and progress to a series of multi-tiered cooling conveyors with as much as a 120-minute conveying/cooling capacity. The pans stay on line in the system while the product is being produced. Empty pans convey to head back to the front of the line to begin the process all over again.
After they cool, the biscuits descend from the conveyor and travel to a vision system that checks for color, size, diameter and height. Any rejected biscuits are dropped into a bin below the system.
“We’re able to produce multiple biscuit sizes on this line,” Adams adds.
Then, the biscuits convey en masse along a series of belts and move into a narrower conveyor line and through a metal detector.
“There are two critical control points (CCPs) and this is one of them,” Adams says.
The groups of biscuits are then diverted from the main line for a quality inspection by operators who assist them into a laner that divides into six lanes as they continue downstream into a slicer, where they’re automatically collated.
Consequently, operators hand pack the groups of sliced biscuits into shallow, bleached white paperboard trays and hand stack them on top of each other in threes as other operators erect new trays. The stacks of filled trays are then automatically wrapped in clear film and are labeled before operators perform another quality control check. The wrapped tray packs are bagged again and convey downline to be code dated and placed into large delivery crates, four bags per crate. The crates are then transported to trailers in a nearby warehouse for direct shipping to customers.
“This is what happens with our fresh product. Our frozen finished products are produced the same way, except that they’re loaded into corrugated shipping cases, are palletized by hand and go into our cold storage facility,” Adams says.
Fresh product customers are served with little or no finished goods storage of the product while frozen products are sent directly to Nashville Cold Storage, another nearby TBC location, for static freezing. The product is on “freeze hold” for a minimum of three days before it can be shipped to the customer.
Setting Goals, Practicing Sustainability
“We found that setting our goals [for the day] by posting them on a white board works best on the plant floor,” Adams explains. “We list on the board where we are in terms of production sequences for the hour, where we want to be and how we should get there. We post all of these actions on the board every hour, so that the people on the line and in the area have a visual and can see the board from the plant floor.”
The company also runs monthly safety training programs that help reduce its incident rates by as much as 75%.
Various environmental compliance programs, cost reduction and sustainability practices have been put into place, the latter program since late 2008, says J.R. Wilson, director of engineering and safety.
“We began several new sustainability programs including recycling and electrical curtailment, and work with different local agencies to be sustainable,” Wilson says. “We also began testing light emitting diode (LED) lighting this year everywhere from office lighting to the high-bay lights. The LED lights have a substantially longer life expectancy, so company-wide, that kind of change can really add up.”
The company installed new drives on facility mixing systems, which allows the plants to ramp up speeds and better control machine demand, Wilson explains.
“We also try to get involved with our local electrical utility companies as much as we can. They can come in and help us do the testing we need to do,” he adds.
Fresh product orders are taken each week or every two weeks, depending on the product, and are built to suit, Adams says. On frozen items, the company keeps a minimum safety stock of two weeks’ inventory.
“We have the cold storage distribution facility that we use internally to static-freeze its products,” Adams says.
In terms of supply chain services, TBC is in the process of working with customers and distribution centers to streamline them onto the same computerized distribution system that encompasses everything from inventory checks to product forecasting, all the way to the store level.
Another key to the successful operation is communication, Adams says.
“We have to stay as flexible as possible and balance that flexibility against tight safety, product quality and speed requirements with communication. The plant has to be able to react to everything. We stay in touch with each other, meet face to face every few hours, go over production schedules, changes and quality all the way through [the day]. And we try to keep this as consistent as possible. We have seen a 50% increase in uptime since 2009 by keeping the communication lines open,” he says.
Adding the new sheeting line and a few pieces of other equipment to increase speeds hasn’t hurt either.
It’s all why TBC’s bun, biscuit and muffin production lines run just like a well-oiled, or in this case, well-buttered, machine.