Dispensing Bins Transfer Weighed Quantities of Ingredients Into Bulk Batching Bags for Faster Handling, Increased Production
S.E. Rykoff & Co., an old line grocery warehouse and manufacturing firm founded in 1911, packages more than 2000 different food and non-food items at its Los Angeles, CA plant. For the food products, ingredients are used in quantities ranging from a few pounds to 2500 lb per batch in making bakery mixes, salad dressings, gelatin dessert mixes, puddings, spices, and other items.
Until recently, most ingredients were received in bags or drums and manually dumped and weighed into mixer hoppers or gondolas. A full scale bulk handling system was needed, but was considered too costly for handling so many items. Mixing stations were congested. Greater flexibility in flow of ingredients was needed.
The company worked with suppliers and an engineering consultant to design a batching system for this application. Key considerations in system design were sanitation, accuracy, speed of operation, and the capability to provide data for inventory and quality control purposes.
A prototype batching weighing system which employs a rail trolley and two types of Intermediate Bulk Carriers (IBC)- collapsible plastic bags and plastic bulk dispensing bins- was designed and installed. In operation, major ingredients are received in collapsible IBC bags holding up to 2000 lbs. each. Bags are emptied into the plastic bulk dispensing bins. To make up a batch, bins holding the desired ingredients (up to five at this plant) are placed on a stainless steel framework for dispensing into a bulk bag. The bag is moved from bin to bin to receive weighed quantities for the batch.
The operator connects each of the five bins to a vibratory tube feeder by a flexible sleeve, and opens the stainless steel slide valve of the dispensing bin. An empty collaspible bag is placed on the rail trolley and positioned under the first bin and its vibratory tube feeder.
Desired net weight of ingredient is entered on a touch panel mounted on the trolley, and the “start” button is pushed. The feeder then begins to deliver product. Delivery starts high speed, then slows to a dribble to finish off the desired amount of the product within an accurancy of +1 lb.
The operator advances the trolley to each station in turn, then to a delivery station beyond the row of bins. There, a forklift truck lifts the filled bag up by its slings and carries it away. The batched load is delivered to a hopper which discharges it into a mixer. This mixer feeds to a filler and packaging machine on the floor below. Minor ingredients are blended in the laboratory and added to the batch in the mixer.
Dry ingredients used in batches of mayonnaise and salad dressings are premixed, then stored in one of the bulk dispensing bins set on a rack. As the dry ingredients are needed, a 200-400 lb batch is weighed into a drum and taken to the wet mixing line.
At present, five major ingredients- flour, sugar, citric acid, dextrose, and salt- are received from suppliers in bulk collapsible bags. Negotiations are underway for suppliers of other ingredients to gear up for bulk bag handling. The polypropylene bags weigh only 5 to 7 lb each, and can be reused for 5 to 50 times. Designed with a 5-to-1 safety factor, they are strong enough to hold a 15,000 lb load.
Bags can be emptied in less than a minute. Polyethylene liners are removed and discarded. Outer bags are folded for return to the supplier when the next ingredient order is delivered.
Sugar and flour supplies are furnished in specific weights so that a batch amount (such as 1400 lb) can be dumped directly into the mixer, along with other weighed ingredients.
Filled bags of ingredients can be stacked three high during shipment and storage, with no pallet separators needed between the layers.
Time is saved. Unloading and emptying incoming shipments packaged in 50 and 100 lb bags took 30 min or more for each load, plus time to dispose of the emptied bags and clean up the spillage. With bulk bags, a forklift truck driver can unload a shipment in less than half the time. Product loss from broken bags has been eliminated. Forklift handling also has reduced the risk of back injuries caused by handling heavy bags individually.
Sanitation also has been improved. Fully enclosed bins with screw-on lids eliminate bag dumping dust and protect ingredients from contamination.
As seen in Food Processing Magazine