Grading and packing fresh produce is a multidisciplinary process, particularly for root vegetables and potatoes where the segregation of clean and dirty produce and the need for washing add complexity to the overall process. In the past, this could entail packers and processors trying to shoehorn equipment from different manufacturers into a line, not always with successful results.
However, as the industry has become ever more professional, so too have those supplying produce-handling equipment, with innovations at all stages of packing continuing to drive investment by growers.
But as Charles Tong of Lincolnshire-based Tong Peal Engineering explains: "Continued downward pressure on costs is driving growers and packers to achieve the most cost-effective and efficient systems in the grading, handling and packing of produce."
He adds: "As a result, increasing demands from buyers, predominantly in the supermarket sector, are leading to investment in new grading and handling machinery to utilise labour and buildings more efficiently."
Efficient operation is at the heart of the firm's latest model of its Caretaker Classic grader, which can be fully customised to suit individual requirements. The largest version, which includes an in-feed hopper, the Evolution cleaning system, an easy-grade screen module and an inspection area, can clean and grade up to 500 tonnes a day. Smaller versions are also available.
The company says that by fitting the Evolution cleaner, the amount of soil, stones and clod that would otherwise need to be picked off manually is reduced, increasing throughput and offering time and labour efficiencies.
Transferring boxed products onto the packing line remains a potential bottleneck in terms of efficiency and also represents one of the key areas where damage and losses can occur if the operation is not seamless. The new Rotatip side-ejecting box tippler from Haith Tickhill Group is intended to expressly address these concerns.
"The system was designed for high-capacity unloading of potato box stores or it can be used as a line feeder," explains director Nigel Haith. "The box is rotated upside down so it totally empties the potatoes, unlike many conventional tipplers that leave valuable produce in the box."
There are no hydraulic controls to remove the risk of product contamination from oil leaks and the tippler requires minimal maintenance. Haith adds that drops have been kept to a minimum to facilitate gentle handling of the crop.
"The system comes in two variations," he adds. "You can have an in-line conveyor or a full-width discharge belt with variable speed control. As long as you keep feeding it with full boxes and remove the empty ones, there is no need for any operator input."
Another machine the company has turned its attention to is the barrel washer. Some five years ago, Haith Tickhill introduced its prototype rotary brush polisher and since then, says Haith, things have "come a long way in a short space of time".
The firm has just launched the mark-two version of its tried and tested Root Veg Polisher, which it hopes gives it an edge over others on the market. "We are fully aware that this type of washing system must not only add value to the product being washed but also be user-friendly, simple to maintain and give hours of trouble-free running," says Haith.
"To this end, the new polisher has a special bearing system that allows quick and easy roller removal from both sides of the machine. Brush segments can be removed without dismantling the drive system and all components are easy to access for maintenance and hygiene."
The machine also features a special patented drive system, removing the need for trunnion wheels to support the drum and allowing the barrel to be run in both directions, giving the brushes a longer working life. "We've invested much time developing unique brush systems and are able to advise customers on the correct brush requirements to achieve the best results for their process," he adds.
Tong Peal has taken a different approach to washing with its new Rotary Spray Washer. It combines washing and polishing to increase efficiency and to allow flexibility and control over crop cleaning. "Unlike conventional barrel washers, the Rotary Spray Washer's high-pressure, high-volume spray bar and adjustable barrel incline ensures that crops are not immersed in water but instead are washed by fresh water through powerful spray jets - therefore receiving an improved wash quality. The spray bar can be fed directly by recycled water from a customer's own water treatment plant or from one of Tong Peal's water tanks," Tong explains.
The company claims that its unique design also allows greater polishing flexibility for growers processing differing types of vegetables throughout the year because it incorporates a range of polishing tools including an interchangeable brush, rubber pintle or plain stainless steel barrel plates. The washer also features a pneumatic air bag that can alter the angle of the variable-speed barrel.
The washer has been supported by the development of a new stainless steel cyclone destoner system that utilises a heavy-duty impeller pump to create water turbulence, forcing the stones to the bottom of the tank where they are removed via a side elevator.
Optical graders for sorting visual defects have been widely adopted over recent years, but the weight grading of particular products has also seen major improvements. Haith has been importing the Sammo weight grading system into the UK for the past 10 years and now has 18 machines in operation. Recent installations have included swede and cabbage packers.
Compared with earlier weight graders, the machine is electronic and suitable for rounded fruits and vegetables such as potatoes, swede, peppers, mangoes and avocados. Its accuracy has found popularity with potato producers looking for accurate sorting because the system's computer uses several electronic sensors, allowing specifications and grading parameters to be quickly changed, even during the grading process.
While there has been a move to sell larger produce individually, smaller items such as salad potatoes and sprouts are still frequently pre-packed. Gainsborough Engineering Company has supplied a second Twin Weighing and Bagging system to Lincolnshire vegetable packer Staples.
The new line, which can produce more than 120 packs a minute at full capacity, consists of an inclined conveyor that transfers washed and sized product to the 16-head weigher. This then streams product into two Gainsborough GV2K3 stainless steel Vertical Form Fill and Seal bagging machines. The bagged product is then elevated onto a rotary collection table for packing in transport containers.
The Gainsborough Vertical Form Fill and Seal machines are fitted with thermal printers capable of date coding and batch numbering the packs. The versatility of the system allows for single weight packing or packing different product weights independently, just by selecting the appropriate program. Staples already used a number of Gainsborough machines and the fact that all the forming tubes are interchangeable between the machines has increased flexibility for the company.
Labelling and packaging is the final stage of the packing line that has seen moves towards increased automation. For example, English Village Salads has recently taken delivery of a Eurokett Junior 115 label applicator from Bradford-based Advanced Dynamics to label flow-wrapped tomatoes. One of the features is the machine's ability to reliably label odd-shaped items across a range of different packaging configurations.
The use of micro-thin polyethylene labels, which provide better adhesion and appearance than paper labels, allows a maximum throughput of more than 80 packs a minute. It can apply front, back and wrap labels and handle a range of packaging types including sachets, trays and cartons.
Advanced Dynamics claims that this, together with speeds of up to 100 packs a minute, makes the Eurokett Junior suitable for anything from mushrooms, olives, soft and citrus fruits right up to vegetables such as potatoes or even pumpkins.
English Village Salads engineering manager Jim Houston says: "I can't fault the machine. We are really happy with it. Reliable labelling is vital to us to help keep production flowing and the Eurokett Junior does just that."
Advanced Dynamics joint manager director Malcolm Little adds: "There has been a steady growth in ready-to-eat salad and fruit packs, meaning fast and reliable labelling of these odd-shaped items is vital to meet demand. The Eurokett Junior is designed to operate in unison with packing equipment, making it ideal for fresh produce processors looking to maximise their production."
Increasingly, equipment providers and manufacturers are able to supply more and more elements of a packing line than before, either alone or by working together. This enables packers to specify ever more bespoke solutions and deliver correspondingly high-quality products to their customers.