Since legislation governing the weight of goods sold was changed earlier this year from one of 'minimum weight' to one of 'average weight', new rules have applied to the use of non-automatic weighing equipment. However, confusion persists among users of equipment.
The Average Weight System legislation was introduced on April 6. But, based on the feedback from a seminar that weighing equipment supplier Sartorius held in June, there is a lack of information about the new regulations, claims the company's quality assurance systems manager Colin Maher.
The legislation requires that all non-automatic weighing systems used for average weight and brought into use after January 2003 must be verified for legal trade. Systems used for verification should be 'robust and sufficiently rigorous', says the Department of Trade and Industry. And record-keeping must include information 'on the recording of any corrections or adjustments made to machines'.
Products that can be manufactured under the average weight control rules range from 5g/5ml to 25kg/25l, although only those up to 10kg/10l can have an 'e' mark on them. The 'e' mark is an EU designation which indicates that food has passed the requirements of the Average Weight System. It includes multiple packs as well as single packs.
But it isn't just regulatory changes exercising manufacturers. In response to pressure from supermarkets, Sartorius is also paying particular attention to methods of reducing give-away with its systems.
"This has never been so relevant to the industry," says Maher. "Identifying key areas of give-away reduction and the amortisation periods of investments must be very high in the consideration of equipment and systems specifiers."
Performance optimisation
Paul Griffin, marketing director of Ishida Europe, agrees that optimising weighing and packing performance is essential, both in terms of quality and speed.
"In the food industry the pace of product development continues to increase and, as a consequence, processors and packers are under increasing pressure to get new products on to supermarket shelves in record time," says Griffin. "New challenges have been created for the weighing industry.
"Standard weighing equipment obviously suits standard products. However, food processors are now finding that conventional machinery cannot guarantee high-speed performance or accuracy if it is required to deal with the increasing numbers of non-standard applications."
Griffin notes that the number of products which fall into the 'non-standard' category is growing. This means that when it comes to an investment in suitable equipment, most manufacturers cannot afford to compromise with the best available from a standard range, he says. This has led to a new type of supplier in the weighing and packing sector.
"While traditional off-the-shelf machinery is cheaper to purchase and install, a look at the total of ownership - downtime, labour, give-away and waste - often proves that bespoke equipment is the more prudent option," says Griffin. "This is particularly the case in situations in which changes of product, pack weight, or type are frequent."
Individual, made-to-order equipment ensures that the solution really does fit the needs of the user, claims Griffin. Improvements in overall efficiency mean that payback periods can be as low as four months, he says. "With demand for speed, efficiency, and bespoke applications on the increase, it is becoming apparent that solutions providers are the future for the food production and processing industries."
No matter what systems are used, one of the most important targets is to reduce give-away. Griffin believes that with today's sophisticated equipment and technological developments there is no reason why give-away should ever be above 1%.
"This even applies to fresh food as there are new weighers on the market specifically designed to handle meat, fish, and similar products," he reports. "The smaller the product the more chance there is of give-away being reduced: it is, for example, easier to control portions of a cubed meat product than it is to get the correct portion of a sliced one."
Equipment integration
One concern that Griffin does have, however, is the lack of integrated machinery. "A production line which incorporates weighers may include equipment from a number of suppliers. Any new line should have all of its items installed from just one supplier so that they can 'talk' to each other. Integration is essential; at present 90% of machines are stand-alone and do not communicate with others."
Griffin goes on to say: "This situation must change if efficiency is to be increased and give-away reduced. But, unfortunately, areas such as the handling of fresh meat are miles away from such methods. Many users struggle to handle just one machine effectively, let alone an integrated line!"
However, Mike Bradley, product inspection business manager with another equipment supplier, Mettler Toledo, believes there are so many operations related to weighing and portion control, which are now integrated into production systems, that many manufacturers are having to invest in products that check the checking equipment.
For example, large production runs may incorporate systems which, in addition to providing data on ingredient quantities, may also control sell-by date information; batch data; metal detectors; and quality assurance information, he says. There are so many operations connected that they, in turn, have to be checked to ensure they are working properly.
"Users of weighing and portion control equipment need to be able to send all of the information possible to the quality control people so that production issues can be identified and tackled as they happen - on the fly," says Bradley. "It is no good making an adjustment to, say, filling and feeding equipment, after a production run has finished. Information has to be gathered and acted upon immediately."
Bradley believes food manufacturers have been greatly influenced by the pharmaceutical industry where the integration of weighing systems with other functions has long been considered essential.
New technology also allows changeovers from one product run to another to be made remotely. "Product weight and all other parameters can be preset and an operator in a control room should be able to make changes simply by pressing a button," says Bradley.
On a more practical level, he also warns against using small, local firms to carry out repairs and maintenance. "This is an increasing trend, but many of these operators are jacks of all trades and masters of none," he warns.
"Often, they do not really understand what they are doing and can make matters worse. Their charges may be lower than those of the original supplier of the equipment, but it is false economy. In addition, it is often the case that such people are called in to work on obsolete equipment that is no longer covered by the original manufacturer and has been operating for longer than the recommended period."
X-ray technology
Loma Systems is promoting the use of X-ray technology for weighing applications in the food industry. "We believe that X-rays should be considered as an alternative to checkweighers," says product manager Alan Johnson. "For example, while the main function of a checkweigher is to weigh product and report upon underfill or overfill, X-ray technology allows manufacturers of food products to analyse pack contents more closely. This leads to more accurate portion control and better production efficiency."
Johnson points out that new regulations and codes of practice imposed by supermarkets on their suppliers are the key drivers for the development of weighing technology.
"They are having a major impact on suppliers which now demand cost-effective and state-of-the-art systems - that is, better products as well as value for money."
With weighing and traceability inextricably linked, customers are also demanding equipment that keeps track of products, from start to finish.
Stuart Hunt, sales manager for the Stevens Weighing Group, cites the example of a recent contract to supply equipment to British Premium Meats' (BPM's) new purpose-built factory in Welwyn Garden City, Hertfordshire.
"BPM set a number of key goals which it wanted to meet for controlling the processing of its fresh and cooked meats," says Hunt. "The minimisation of waste and give-away was, of course, very high on the list. But many other areas had to be addressed, such as improved meat traceability with a paperless audit trail; increased stock control and efficiency; improved labelling; and an overall reduction in processing time. In addition, the system needed to be user-friendly so that operators would readily accept it."
A further requirement was that the Stevens' weighing equipment had to operate in harmony with BPM's software package to provide a fully integrated system incorporating the factory floor and the back office.
This installation clearly illustrates that, regardless of legislative changes, the use of checkweighers in isolation is becoming a thing of the past. Packing, labelling, stock control, auditing and traceability are increasingly an integral part of the package required by users both large and small.
Key ContactsIshida Europe 0121 6077700Loma Systems 01252 893300Marco Weighing 01342 870103Mettler Toledo 01162 350888Sartorius 01372 737106Stevens Weighing Group 01254 685200