BS shows how to cut losses
by Robert Harris
BETTERbeet storage is on the cards following five years of on-farm studies by British Sugar.
The company is increasing its efforts to help growers improve their storage techniques, minimising losses, and making stores easier to manage.
Focus on Beet Storage follows the Quality Harvesting Programme which halved sugar beet field losses on tested farms in three years.
The storage scheme continues BSs commitment to pass research findings to growers, says Mike Armstrong, head of r and d.
"Storage is a natural extension of the harvesting work. Both these initiatives have stemmed from earlier research. Theres no point coming up with good ideas unless we can put them into practice."
The scheme will offer advice on clamp siting, design, filling, access and monitoring. Between 50 and 60 growers, with stores between 250-1000t, are taking part this season. Eventually, all growers will be able to participate voluntarily.
The work builds on earlier research triggered by heavy losses during the hard winter of 1991/2. Many growers suffered from frosted beet and consequent rejections. But the main losses, which often remain hidden, are from overheating, Dr Armstrong maintains.
Losses from well-managed stores average about 0.15% of adjusted sugar weight a day. The late delivery bonus which allows for 0.2%/day more than covers it, he adds. And it is not hard to achieve. "We have stored beet for as long as 124 days at an average of 0.125%. Beet can be stored very effectively for longer periods of time than will be needed in practice."
The programme kicks off with a comprehensive check list which pinpoints any likely trouble areas. The list will also serve as a record for future reference, to highlight other problem areas which may appear at unloading, he explains.
Good ventilation is the key to avoiding overheating, says Dr Armstrong. Too wide or deep a clamp, and/or filling it with dirty beet, can cause overheating. But leaving sheets on after a frosty spell is the main culprit. "During our research in 1993 we deliberately left the clamp sheeted after a frosty spell. We managed to end up with a temperature of 28C."
With a little care, internal clamp temperatures can be kept as low as 5C on average during the winter months, he claims. To help growers spot trouble early, BS is testing the practicality, reliability and robustness of temperature probes developed last year. These are inserted through alkathene pipes placed in the clamp during filling.
"The internal temperature should follow the ambient air temperature, with a day or twos time lag, in a well-ventilated clamp," says Dr Armstrong. It is important to compare the two – only when clamp temperature rises independently of the outside air temperature is it time to worry, he explains. "But the first area we shall look at is the quality of the beet being stored. There is a very strong link between good harvesting and good storage – if damaged beet is put into store, you start off with a problem. It accelerates respiration, and allows fungal and bacterial pathogens in which increase storage rots."
"From the outset, we want to make it clear that the focus is farmer-friendly," he adds. "Clamping is not a precise art. Each farm is different, and we shall recommend techniques which will not cost a fortune and which can easily be put into practice on that farm. We are looking to take the hassle out so it is no longer an issue for growers to store beet."n
Harsh winter weather is seen as the main danger to sugar beet clamps. But oft-hidden damage from overheating is the main cause of losses.
Frosted beet problems spawned further storage work by British Sugar.
• Practical on-farm advice to reduce losses in store.
• Site, design, access, filling and temperature monitoring.
• 30 growers this year.
• Voluntary programme for all growers soon.