Keeping It Fresh: Baggers and Closures
June 1, 2010
by Shane Whitaker
Less than a century ago, bread was sold unwrapped. Not until the first slicer was introduced in the late 1920s did it become common to wrap bread to preserve its freshness and moisture. The first slicing machine was introduced to the baking industry in 1928, and it still stands today as a hallmark invention — we’ve all heard the saying, “the greatest thing since sliced bread.”
Bread was originally overwrapped with opaque waxed paper, and then companies turned to transparent packaging such as cellulose film. One of the major problems with overwrapping bread this way was that once the packaging was open, it was difficult to close it again. Bags have been used the last 50 years, and reclosable clips and ties allow consumers to re-secure bags after use so that product stays fresher longer.
Today, bags premade from low-density polyethylene (LDPE) are the most common materials for packaging bread and buns. LDPE is a lower-cost option compared with cast polypropylene, which also is used for packaging bread. LDPE provides a good moisture barrier, but its optics generally are not as clear as the cast polypropylene nor its touch as crisp as cellophane.
When it comes to bagging equipment, bakers desire reliable machinery and automation systems to eliminate downtime, quick and easy changeover capability, and service and parts availability for ongoing maintenance, according to Dennis Gunnell, vice-president, sales and marketing, Formost Fuji Corp., Woodinville, WA. Bakers are also looking for environmentally friendly systems that use minimal electricity, compressed air and materials, he added.
Formost Fuji offers two models for bagging bread. “The GTS is our top-of-the-line bagger model with a servo overhead option, easy-to-operate touch screen, gentle product handling and the latest computer and electronic systems,” Mr. Gunnell. The second, the FFB model from Formost Fuji, is widely used for tortillas as well as bread, buns, rolls and other varieties of bakery products.
With the focus on sustainability, Formost Fuji has worked to reduce the electrical and air consumption of its machines, according to Mr. Gunnell. In addition, he noted that the company continues to make improvements to sanitation, adhering to BISSC with a 3A Diary-certified model available.
Whereas Formost’s baggers use a paddle that pushes the loaf into the bag, AMF Bakery Systems’ two high-speed automated bread baggers — the Mark 60 and the Mark 75 — employ scoops that pull the bag over the product, according to Larry Gore, director, sales and marketing, AMF, Richmond, VA.
AMF redesigned its bread baggers during the past couple years, and its scoops are now driven by a patented pendulum scoop drive system. “The pendulum rotary system does not stop and start, greatly reducing maintenance requirements and also increasing longevity of the machine as well as the speeds at which it can operate versus the traditional cam-operated scoop drive,” Mr. Gore observed.
As their names suggest, the Mark 60 can bag up to 60 1-lb loaves per minute but generally runs in the 50 to 55 bags per minute range, while the Mark 75 is designed to sustain speeds of 60 to 65 bags per minute with capability of up to 75 1-lb loaves per minute.
The two baggers operate using the same principles, with the main difference being the robustness of the equipment, according to Mr. Gore. “The Mark 75 is built heavy duty for the higher rotation speeds,” he noted.
AMF also added a patented flusher discharge conveyor, eliminating the flusher bar on its baggers. The flighted conveyor moves product away from the scoops so the next product can be bagged. “One of the problems is a flusher bar at high speeds has a tendency to kick the product harder, causing it to turn over,” Mr. Gore said. “Our flusher conveyor sets the product down gently onto the conveyor.”
The THG 2000 bread bagger from The Henry Group is a mechanical machine that the company has manufactured for many years, and it is “tried, true and proven,” according to Darren Jackson, vice-president, business development, The Henry Group, Greenville, TX. “Our bagger is really smooth, and we put a timing belt on it to keep the bagger from working against itself,” he said.
The unit can bag up to 70 loaves per minute, but slicers generally are not able to reach that speed. Slicers usually run about 45 to 55 loaves per minute, thus they are the bottleneck, according to Mr. Jackson.
One of the more critical operations for the baggers is getting the mouth of the bag open and holding it that way until the loaf is bagged. “Anything you can do to reduce bag flutter and keep that bag stable and from moving around will improve the bagging situation,” Mr. Jackson said.
The bread bagger also features automatic bag changers. The wicket table carries with two sets of bags and a photo eye monitors the current wicket. When one wicket empties, the table slides to the next position and keeps bagging without interruption, according to Mr. Jackson. “The automatic changer enables the operator to do a more such as run two baggers,” he said.
Automtic rotary bag feed tables from Formost Fuji facilitate fast changeovers and wicket changes, according to Mike Day, Northwest regional manager, Formost Fuji. “This works well with just-in-time manufacturing because of the flexibility it offers,” he added.
AMF’s baggers offer a precise bag inflation system that injects air into the bag. “Much work has been done over the past couple years to get a precision system that inflates the bag each time, and the wicket table designs have been reworked to give better support to the bags so the blow-up is more precise,” Mr. Gore explained.
AMF also improved the electronics on its packaging machines as well as the electronic synchronization between the bagger, the slicer and other upstream
equipment, he said. “This eliminates mechanical connections between the machines, thus saving on maintenance and downtime,” Mr. Gore continued. “Anytime you have mechanical chain drives, or even belt or shaft drives, you have maintenance you must do on them. Our machines are basically electronically synchronized with each using their own separate drives.”
Additionally, the electronics package offers recipe-driven control systems so operators can set up the bagger and slicer for different products easily. “There are still some set-ups such as guides that have to be done mechanically, but the majority of set-up can be completed with the push of a button at the operator interface, changing from one product to another, including speeds, lattice set-up at the slicer, etc.,” Mr. Gore explained.
When bakeries acquire slicers and baggers together from AMF, the equipment manufacturer offers a new common conveyor between the two pieces of equipment. This permits smoother transfer of the sliced loaves to the bagger, allowing higher speeds and gentler handling of the loaves, he said.
The Henry Group integrates both the slicer and tyer with its baggers. “The discharge conveyor on the slicer is slave-driven off the bagger, so once it passes the blades, we drive off the slicer into the bagger,” Mr. Jackson said. “This is necessary to get accurate timing between the two pieces of equipment and because you have a flighted conveyor to feed the scoop bay.”
Also, every new bagger the company builds is equipped with a network switch that ties into a bakery’s central system. Because of this, all baggers will have dedicated IP addresses. The Henry Group also incorporates color touch-screen panels on all of its baggers because that is what customers want, according to Mr. Jackson.
In addition to building its own bread bagger, the company also reconditions older bread baggers. “If a company has an old Mark 50, we gut it and build them basically a new bagger, but it costs about 20% less than a new bagger,” Mr. Jackson added.
AMF, the OEM for the Mark 50, is in the R&D process of developing a bun bagging machine, according to Mr. Gore.
“We put a lot of effort into re-energizing our bun bagging business,” said Dale (D.J.) LeCrone, c.e.o. of LeMatic, Inc., Jackson, MI. The company builds packaging lines that take the buns from the cooler, index and orientate them, slice them, stack them and put them in a bag.
LeMatic has made its bun baggers more operator-friendly, eliminating manual adjustments. “Our original baggers were extremely adjustable, and we could run many things,” Mr. LeCrone said. “But because they were adjustable, people had to be able to understand and
operate them. What we found prevalent in today’s workplace is that operators are changing more frequently, and bakeries are even using temporary workers in some cases. So we have had to make our machines as flexible as possible with as few adjustments as possible.”
The OEM began incorporating servo drives about three years ago to allow smoother operation, longer runs and faster speeds. Also, it improved the information systems, allowing Ethernet connectivity to make the bagger an integral part of the whole bakery system, Mr. LeCrone added. “The driving force is that information is power, and if you know what is going on — what products are running, how fast they are running and if there are any issues on the line — you can continually make better decisions,” he said.
Slicers are not a bottleneck for bun baggers, according to Mr. LeCrone. Its baggers are capable of running 70-plus packages per minute, depending on package type, and its slicers can process product for up to 100 bags per minute, he stated.
LeMatic’s baggers are versatile and can create a variety of package formations. Changeovers are straightforward and fairly quick, and they can be automated to the level that a bakery needs. “We automate what makes sense and leave manual where that makes sense,” Mr. LeCrone said. “It is not always cost effective to put a motor on all parts. We have to be cost competitive, so sometimes it makes sense to have manual guide adjustments to keep costs in line.”
After bagging, the product enters a closure unit that is generally integrated to the bagger. It applies either a tab lock closure or twist tie on the neck of the LDPE bag. Instead of plastic clips or twist ties, a bakery could opt for tamper-evident tape, but this closure system is not as popular as the other two options.
The decision to use either tab locks or twist ties is generally one the bakery will make based on a marketing decision, according to Mr. LeCrone. Mr. Jackson said certain closures are preferred in particular markets, noting that twist ties are generally used by bakers in the South.
Next year will mark the half-century mark for the first automated twist tyer built by Burford Corp., Maysville, OK. The company developed its first mechanically driven twist tyers in 1961, according to Don Ivey, sales account manager, Burford. The tyers were reliable but a lot noisier and required more maintenance because of moving chains and parts than today’s servo-driven twist tyers, he observed.
The company launched its first servo-driven twist tyer in the mid-1990s, and nearly three years ago, Burford updated the machine. “After having our servo twist tyer in the market for 12 years, we were looking to do a redesign,” said Mitch Lindsey, technical sales, Burford. “We listened to complaints from our service techs and plant engineers as to what were common failures and what they would like to see changed, and we incorporated all we could in the new machine.”
Its newest model features brushless DC motors that last longer than the previous motors. “When we originally designed the servo tyer, brushless motors weren’t available,” Mr. Ivey said. “We also made a lot of improvements with new electronics that are now available.”
In addition, the new unit uses less twist-tie material, thus companies are able to save on materials, according to Mr. Lindsey. “It also consumes approximately 10% less power than the previous model,” he added.
The new twist tyer features a lightweight, removable head. “Ergonomically, it is easier for maintenance to access everything,” Mr. Lindsey observed. “A sealed-end coder also extends the life of the motor. It’s been almost three years since its launch, and we have not seen failures in those areas. That was our hope when we did the redesign.”
Burford’s newest twist tyer can operate at speeds as high as 110 bags per minute, and it has proved this by running a machine for several hours at this rate at a bagging machine manufacturer, according to Mr. Lindsey. “The only way we have seen it run that fast in production is to be fed by two baggers,” he added.
Kwik Lok Corp., Yakima, WA, is unique in that it not only builds the bag closing equipment but also produces the tab lock closures that run through the equipment. “There is no need for two sources of supply to close the bags,” said Hal Miller, vice-president of sales. “Kwik Lok is the original; we are not a copy.”
Kwik Lok offers both fully and semi-automatic bag closing equipment to serve the packaging needs of the baking industry from the small mom-and-pop operatoins to the large corporate bakeries, he said. “We offer closing equipment for high-speed lines, up to 120 bags per minute; machines to close paper bags; as well as specialty bag closing equipment for pita bread and tortillas,” Mr. Miller said, noting that the company has been in the bag closure business for 56 years.
The company’s closures open and close the same way each time. “The shape of the Kwik Lok closure does not change,” Mr. Miller added. “It does not become wrinkled and twisted, making it difficult to use. The fact that the closure does not change shape makes the code always readable when printed on the closure.”
One of its newer pieces of equipment has a standard model that allows the machine to apply either a closure label or simply a closure without the need for any additional equipment. Kwik Lok is further developing its laser printing options.
The manufacturer is able to accommodate bakeries’ enhanced printing requirements from “best before” dates to real time and scannable barcodes for traceability and promotional opportunities. “We are seeing an increase in the desire to offer cross promotion and couponing programs in the bakery sector and now have the ability to offer scratch-off game possibilities for fundraising opportunities,” Mr. Miller added. “We are able to meet this need by using the Kwik Lok closure label.”
Today’s baggers and closure systems are faster, smarter and more efficient than ever because equipment manufacturers continue to look for ways to improve and enhance their machines for today’s high-speed bakeries that require less downtime and greater output. ◾