Awareness of the combustibility of dust was high when the Clayton plant was on the drawing board. Only two years had passed since the Imperial Sugar mill in Savannah, Ga., exploded, killing 14 and badly injuring scores of other workers. Like sugar, flour particles can easily meet the sub-420 micron threshold for ignition in a confined space.
While risk assessments of flour sifters and other vulnerable areas are ongoing at many bakeries, NFPA standards can leave plants vulnerable when transporting flour, maintains Nick Hayes, president of Volkmann Inc., Bristol, Pa. The standard excludes confined areas of less than 8 cubic feet. "That's not adequate," Hayes insists. "I don't want to be standing next to a 65-gal. drum when it explodes."
The manufacturer of vacuum conveyors is the first supplier in its category to receive ATEX certification from TUV, the German equivalent of UL. Metal-to-metal contact can ignite fine powders, Hayes says, and European standards account for that potential, whereas U.S. standards do not. Besides explosion-proofing, all-stainless construction and a dense-phase vacuum system that results in less product degradation have helped elevate his firm to preferred supplier status with OEMs such as Reading Bakery Systems.
Serpents from down under
High-yield baking is the focus of Auto-Bake, a Sydney, Australia-based fabricator of ovens and ancillary equipment that works closely with Dunbar Systems in suburban Chicago to deliver integrated production systems. Yield plunges when changeovers and washdown occurs, notes CEO Amanda Hicks, "and one of the fundamentals of design is the ability to keep a system clean while running virtually on a 24/7 cycle."
Serpentine ovens that shrink a linear oven's footprint to almost a third are Auto-Bake's hallmark. The firm also fabricates modules for automatic depanning, pan washing and other functions. Another innovation is an infeed design that allows bakers to remove depositors and other ancillary equipment for cleaning without stopping the line by swapping in duplicate components. Engineers also have eliminated many of the transfer points typically found in integrated lines. "That's where things go wrong and you have product damage and downtime," says Hicks.
Automated production would come to an abrupt halt if automated product transfer did not occur, a reality that elevates the humble conveyor to the status of critical component. A concerted effort has been made to improve the sanitary design of belts and frames to eliminate harborage areas and optimize cleanability.
For example, Ashworth Bros. Inc. eliminated a bridge weld with open areas around the weld and rod end because of the potential for food debris to become trapped, replacing it with the Omni Pro zero-tension buttonless weld. The firm also created a metal/plastic hybrid belt for spiral freezers that convey sticky products that are difficult to release from a wire mesh surface.
"The majority of our belts are used in both meat and baking applications," according to Kenneth King, commercial support manager at Winchester, Va.-based Ashworth.
Dorner Manufacturing Corp. had the same processing segments in mind when it introduced a stainless steel, tool-less belt slacker unit called AquaPruf. The Hartland, Wis., supplier upped the ante seven years ago with a high-pressure washdown version designed to meet the AMI sanitary principles. The system generated good adoption in meat and poultry, but indifference in baking applications led to a simplified, more economical version.
"We are selling some sanitary conveyors (to bakeries), but it is typically to higher end customers and only for a specific application," says marketing director John Kuhnz. "FSMA has not impacted the bakery industry as of yet."
That view wins grudging agreement from Reiser's McIsaac. As a member of the American Society of Baking's committee charged with upgrading the voluntary BISQ standard, McIsaac discerns tension between what customers are demanding and where mainstream bakers are in terms of sanitary expectations. "I'm not convinced (sanitary design's) a priority in the bakery world," he confides, "but the ones who make it a priority are our target customers."
If it isn't a mainstream priority yet, it will be, predicts Jill Batka, president of Dynamic Conveyor Corp., Muskegon, Mich. The fabricator of V style conveyors branched into the baking world a few year ago with an easy-disassembly version of its conventional conveyor. The units use solid, extruded thermoplastic belting that doesn't slip or fray, a problem of growing concern. (Ellison's is contemplating replacement of cloth-belted conveyors with vibratory units because frayed belts pose foreign-material contamination issues.) In a factory field comparison with interlocking belts, the solid thermoplastic belt reduced cleaning cycles to 13.5 minutes vs. 21.6 minutes and water use to 105.9 gallons vs. 190.7 gallons, the belt's designer reported.
While high-pressure washdown rarely is applied in baking operations, minimizing cleaning time is a benefit every baker can appreciate. With allergen removal an area of growing concern and food safety expectations ratcheting up, it's only a matter of time before the mainstream joins the leaders in boosting production by improving hygienic design.