Depositing: Filling with Precision
November 01, 2009
by Shane Whitaker
If a bakery exceeds its target weight by 5 g per deposit and produces 500 units per minute, it wastes more than 330 lb per hour. Oftentimes, products and fillings that could be over-deposited are expensive, and bakeries would not want to throw away more than 330 lb of product every hour. However, if their depositing systems are inaccurate, that is exactly what might be happening.
Bakeries commonly bias deposits high to reach desired product weights, and it is not uncommon for piston or volumetric depositors to scale 2 to 10% over the desired product weight, according to Steve Crocker, product sales manager, The Peerless Group, Sidney, OH. “If they can be more precise in their accuracy, they can be more precise in how much they have to be above their net quantity weight,” he said.
To this end, Peerless recently introduced its new Precision Depositor, which it claims has a deposit variance up to 10 times more accurate than piston-type depositors.
Bakers want their depositors to be fast, flexible and accurate while being easy to clean and maintain, ac- cording to Eric Riggle, vice-president, Rademaker USA, Hudson, OH. “Rademaker is constantly paying attention to these five areas when making improvements and advances to our depositing disciplines,” he said. “However, not every depositor can address each of these areas.” For this reason, Rademaker produces three different types of depositors — piston, gearwheel and Mohno pump — each with their own set of options to provide our customers with the correct solution to their depositing challenge.
What bakers desire most from their depositing systems is quick access to recipe storage for fast product changeover and heavy-duty machines designed and manufactured for 3-shifts-per-day production, according to Lance Aasness, vice-president of sales and marketing, Hinds-Bock Corp., Bothell, WA. In addition, he said they want the flexibility to run a wide variety of products and to rapidly change from pan to pan or product to product.
John McIsaac, vice-president, strategic business development, Reiser, Canton, MA, also noted flexibility as a key feature. “Small- and medium-size bakeries do not want to buy a piece of equipment that is dedicated to one job,” he said. “To be truly useful and pay for itself quickly, machinery must adapt to the customers’ needs and demands. In the smaller bakeries, the bakers want a machine that can be rolled around and perform multiple tasks with multiple products and a quick cleanup in between.”
Peerless displayed its patent-pending Precision Depositor for the first time in October at iba in Dusseldorf, Germany. The company worked on the new design for the past three years and field tested the product for the past year, according to Mr. Crocker. “We developed our new MassFlow metering and independent scaling system to solve our customers’ problem of costly giveaway,” said Andy Hovancik, president and general manager, Peerless. “Depending upon a customer’s volume, product cost and application, the Peerless Precision Depositor can pay for itself in less than a year by improving portion control and reducing deposit variance.”
In one case, the company proved the new depositor will save a company more than $500,000 annually, according to Mr. Crocker. Peerless incorporated mass-flow metering into the dosing controller and software technology. These meters, which use Coriolis technology, are the most accurate measuring devices for food or any liquid product, he added.
Besides accuracy and repeatability, throughput is also important, according to Mr. Crocker. “With volumetric or piston-style depositing, there is a recoil action, and the piston has to come back before it can actually go forward,” he explained. “The Precision Depositor has a pinch valve that opens and closes, so our recoil is the closing action, which takes less than half of a second.”
Precision Depositors use programmable recipes and ultra-quick calibration at startup for rapid changeovers. The automated depositor features a touch-screen panel on which operators can quickly change from one recipe to another.
Also, the company branded the new depositor with the Peerless name as opposed to Fedco, which is the brand of its traditional piston depositors. The new depositor is able to handle particulates such as raisins, blueberries and nuts, but it may not be able to handle larger pieces such as apple chunks. It is able to accurately make deposits as small as 10 g.
Guaranteeing weight accuracies is difficult when it comes to depositors because the type of filling has a lot to do with it, according to Mr. Riggle. “A blueberry that weighs 2 g can throw weights off because of uneven distribution in the hopper,” he said. “We do offer weight accuracies but they are on a caseto-case basis and always based on a smooth filling because we cannot guarantee particulate size and placement.”
As far as new products being deposited by its equipment, Rademaker is not seeing a big difference in the types of fillings, according to Mr. Riggle. However, the number of finished products with filling inside has increased. “We are depositing fillings inside of bread products, pastry products, croissants, pizzas and calzones,” he noted. “The most common applications for our depositors are applying a filling such as a cream cheese and fruit inside a pastry or croissant dough. We also do a fair amount of filling pie shells with large particulate fruits and meat.”
Rademaker’s piston depositor addresses the budget-minded customer looking for a flexible and accurate depositor, but with a reduced initial investment, according to Mr. Riggle. “These depositors are slower in speed and have more moving parts to clean and maintain than its other equipment offerings,” he added.
Its gearwheel depositors are for customers looking for speed and accuracy. However, because of the design of the pumps, it is not suitable for particulates larger than a ¼-in. square. This depositor is the easiest to clean and maintain of all the Rademaker depositors with very few moving parts, according to Mr. Riggle. The depositor can also be designed to automatically hinge open so that a baker has access to the entire inner workings of the depositor for cleaning and maintenance.
The Rademaker Mohno pump depositors are designed for speed, accuracy and flexibility when it comes to a wide range of fillings. “Each lane of a Rademaker Mohno pump depositor is individually driven and can be shut off or adjusted,” he said. “We tie many of these depositors into a no-product/no-fill system so that the client does not waste expensive filling or time cleaning up. This machine is extremely gentle on fillings with particulates in it.”
Hinds-Bock manufacturers a variety of depositors for the baking industry, and one of its latest machines is designed for injecting creme or fruit where the entire depositor dives for injecting a second product into the first. “This enables our customers to address the markets’ desire for new and complex multi-flavored products,” Mr. Aasness said.
Through the decades, Hind-Bock’s piston depositors have proven to be very accurate by calculating standard deviation over a large sample population, he added. However, its new servo driven pump fillers are even more accurate, often ± 0.3% depending on the product. “The servo pump filler can also be easily integrated with a checkweigher for real time automatic weight adjustment,” Mr. Aasness continued. “Weights can also be fed forward to adjust the depositor to make label weight.”
Reiser focused on developing its pumping systems to deliver an exact-weight deposit with the same integrity and look as the product that went into the hopper, according to Mr. McIsaac. “We have optimized our feed systems to gently handle the products and deliver the product precisely at the weight and form the customer is looking for,” he said.
The equipment manufacturer also worked to make production more scalable with more flow divider options so a single machine can deliver multiple deposits simultaneously. “Spot depositing has been a point of emphasis,” he added. “We have developed new valves to deliver very small portions quickly and accurately.”
Reiser measures the performance of its depositors by tracking the standard deviation of the deposits they produce. “While we see different performance levels with various products, we are generally not satisfied unless we have a standard deviation that is within 1% of the target,” Mr. McIsaac said. “Our use of vacuums and our ability to mechanically guide product into our doublescrew pumping system provides the opportunity to greatly increase product savings compared to traditional gravity-fed systems.”
Lastly, sanitation has become a forefront issue in the bakery, and bakers will pay for depositors that can help them lower their risk, according to Mr. McIsaac. To this end, Reiser improved the sanitation of its depositors by following the path of the product to ensure that they can be quickly exposed for cleanup and inspection and to make sure this can be done with minimal or no tools. “We never allow ‘dead spaces’ where product can stagnate; we positively move product from the hopper to the point of deposit,” he said.
Another key, he noted, is that the company always installs its equipment and spends time with the people who are going to clean and take care of the machine. “Our machines are easy to clean and need minimal maintenance, but we make sure our customer understands what needs to be done to keep the machine in tip-top shape,” Mr. McIsaac observed.
Peerless’ new depositor offers a clean-in-place (CIP) system, and the entire machine does not have any O-rings or other parts to disassemble during sanitation, Mr. Crocker explained. The CIP system’s tri-clamp connection feeds directly to a waste receptacle.
The Hinds-Bock servo pump fillers can also be outfitted with a CIP system, which greatly reduces sanitation time as well as long term spare parts purchases, according to Mr. Aasness.
To speed sanitation, Rademaker focused on offering no- or limited-tool disassembly, Mr. Riggle noted. “We offer the hinged design, as an option on the gearwheel depositor, which really speeds up the sanitation,” he added.
Equipment manufacturers have made some major leaps forward in recent years to offer bakers the most accurate depositors for dispensing their products. The newest designs feature servo motors and flow meters to help eliminate waste and over-deposits and to ensure that bakeries are more exact than ever before in meeting net weights. In addition, suppliers have continued to improve designs so that depositors are flexible and easier to clean and maintain.