Building BLTs like BMWs
If there's one thing BMW knows how to do, it is how to manufacture high quality cars and stay in business. Despite being continually squeezed by low-cost competition from the world's automotive industry, it still manages to give its customers what they demand, and make serious money.
Many manufacturers in the food industry can only dream of keeping their customers satisfied and making a decent profit. Now, however, that dream can become reality. A BLT can be built like a BMW.
It's all to do with improving overall equipment effectiveness, or OEE, suggests Colin Platt, applications specialist at East Grinstead-based Marco Weighing Systems. "I do a lot of cold calling in the food industry. If I start talking about efficiency improvements, I've got their attention immediately. But if I start talking about weight control, I lose them. Weighing is the last thing the story is about.
The car industry in the west has survived by being as efficient as possible, says Platt, by investing heavily in improving its OEE. Now the food industry is learning to borrow from the car industry and do the same. And the BLT the bacon, lettuce and tomato sandwich is a good example of what is happening. But the same principles and the same technologies can apply to everything from making pizzas and assembling ready meals and fruit salads, to packing soft fruits.
"Let's take a sandwich maker producing a BLT. One or two things can be done automatically, such as applying a dose of butter and scraping it on to the bread. But the rest will be manual. There will be maybe four operators, say, two either side of the line, putting in a handful of bacon pieces perhaps 30g a time, depending on the sandwich specification."
The problem, says Platt, is how do you control how much bacon the operators put in; how do you improve overall equipment efficiency? What Marco has done is develop a "go/no go traffic light weighing system called LineMaster. In the case of the BLT it would be a take-away weighing system that weighs how much ingredient is removed from a bin, hopper or tray, rather than how much is added to the end product.
And instead of the operator having to watch a scale or digital display, LineMaster uses a simple red, green, and amber light system that tells the operator to drop a few pieces of bacon back on the tray or take a few more to get the correct weight.
"Take-away weighing systems avoid double handling," says Platt. For packing soft fruits, however, a positive or add weigh version of LineMaster system would be used to determine how much fruit has been added to a punnet or pack.
Since LineMaster was introduced a few years ago, Platt reckons Marco has installed over 1,000 systems in the food industry to improve portion control, reduce give-away, and improve OEE. However, as the use of traffic light systems such as LineMaster has taken off, some food manufacturers have begun to realise that not all production operators are created equal.
In the case of the BLT, for instance, some operators on a sandwich filling line will consistently tend to put in a bit too much bacon. "On a 30g portion with a ±3g tolerance, some operators will be regularly putting in 32.6g, for instance," says Platt. Nice for the consumer, but not so good for the food manufacturer. OEE demands that something be done to improve efficiency by reducing that give-away, suggests Platt.
"So what we have done recently is develop a unique piece of software called Automatic Optimisation. It records every weight that's added to or taken away from a scale by every operator. And when it recognises that an operator is consistently working to the top end of the tolerance, it will automatically adjust that operator's traffic light settings to reduce the amount of ingredient they use. The system is totally transparent to the operator. They don't know anything is happening."
The result is that in a recent installation at a company making BLTs, as it happens Marco was able to bring down the average bacon usage on a 30g ± 3g target portion size to just 30.1g. "We saved them 11t of bacon a week £283,000 a year for an installation that cost less than £50,000," says Platt. "If you can apply the Automatic Optimisation concept to every operator on a production line, then you are talking big bucks savings. You end up with the best possible yield for the packer and the most consistent product for the consumer."
But if weighing by itself is not what this story is really all about, then bacon certainly seems to be. Danish food company Tulip (formerly Danepak) is using British technology to help it slice its bacon better. Norwich-based AEW Delford has been working with Tulip to develop its high speed SmartSlice Vision system for automatically slicing and portioning fresh and chilled boneless meat products such as bacon and pork loins.
It uses a high speed three dimensional camera vision system to scan the leading face of a bacon joint or loin prior to cutting or slicing it. It then determines the area and the ratio of fat to lean. By taking into account the different densities of lean and fat, the system can then calculate how thick to cut the next slice.
By adding a weighing and grading system from sister company Delford Sortaweigh, SmartSlice will cut a number of meat slices or portions and send them into, say, 10 different "channels. But when it weighs the next slice or portion, it will rapidly calculate which channel to send it to in order to produce 10 packs of meat each as close as possible to the target weight.
For certain products the system can reduce the giveaway on average weight packs to well under 1% of the target weight, claims Delford. The company is now looking at applying similar technology to the cutting of Dutch Leerdammer cheese. The problem with Leerdammer is that it is full of large holes or "eyes". Delford is developing a way of calculating the "loss from the holes in order to cut portions to the right weight.
British weighing and portion control technology is also helping Arla Foods, the Danish-Swedish dairy farms cooperative, to cut cheese the way supermarkets want it today in fixed weight portions and also make a profit. Arcall Wright Pugson of Wareham in Dorset has developed a fixed weight cheese cutting system that uses lasers to profile the cheese cross section and then automatically adjusts portion sizes. The aim is to minimise give-away and maximise the number of portions that can be cut from a standard nominal 20kg block of cheese.
With the new machine Arcall has guaranteed Arla a give-away of under 1% on 250g pieces and guaranteed that 95% of all the pieces will be acceptable. In fact, says Arcall, the machine is currently running at 0.4-0.6% give-away with 97-98% acceptable pieces. Typical give-away for traditional fixed wire frame cheese cutting machines is around 3-4%, says Arcall.
What the machine does is use wires to cut the 360mm long by 180mm high by 280mm wide block of raw cheese down its length into two, three or four long "sticks which are sliced in half horizontally into four, six, or eight sticks 90mm high. The machine then takes two sticks at a time, weighs them and laser profiles them to detect any bowing and/or rounding of corners and other dimensional irregularities. From this data the machine calculates the size of each portion and the optimum number of portions to be cut. Each stick is then automatically indexed forward and cut off to the required length by a guillotine blade.
With 1% give-away costing Arla some 1m Swedish Crowns a year (around £70,000) for this particular cheese line, the new machine should speed up packaging and reduce costs. And the advantage for Arla's customers, the supermarkets, is that with every portion being a theoretical 250g, if it has X portions, selling at Y pence per portion, then it has £Z value on its shelves. Fixed weight portions also make it a lot easier for supermarkets to make 'buy one get one free' offers.
The result of this pursuit of OEE means many weighing companies have had to become almost IT systems companies. Using their knowledge of weighing and portion control on the factory floor, they have been able to steal a march on traditional software houses and develop IT and production line control systems that suit the food industry. Marco, for example, has recently opened a dedicated software solutions centre on the outskirts of Leicester.
Indeed, many equipment suppliers are keen to get away from being seen as weighing companies. 'We are not weighing companies, we just happen to be experts in weighing,' is the message today. FM
KEY CONTACTSAEW Delford 01603 700755Arcall Wright Pugson 01929 554884Delford Sortaweigh 01255 241000Marco Weighing Systems 01342 870103
