Heres how to stay on top

19 November 1999




Heres how to stay on top

British cereals are among

the best in the world and

research funded by the

Home-Grown Cereals

Authority aims to keep it

that way. Last week, industry

experts gathered at the

Camden and Chorleywood

Food Research Association

to hear the latest

developments. Charles Abel profiles seven top topics

1 Strob effects

Do strobilurin fungicides affect breadmaking quality? Initial results from a major project designed to find out suggest they may.

So far, only Hagberg and protein content have been scored for the Malacca, Hereward and Rialto drawn from NIABs fungicide interaction trials. Ten spray programmes using varying rates of strob and triazole fungicides were compared.

Protein content and Hagberg varied between fungicide treatments, by 0.8% and 65 points respectively. But no clear link to strob use has yet been confirmed.

Project leader, Sue Salmon, of CCFRA urges caution. "It is early days and we are in the middle of extensive tests of breadmaking quality. It is too early to draw firm conclusions."

Indeed, differences between varieties were far greater than those between fungicide programmes. But ADAS trials have already suggested a 1.2% protein drop where strobs are used.

"We hope this work will not only show us whether there are any effects in breadmaking quality, but what, if any, action should be taken by farmers in response," says Mrs Salmon. Further data, including any evidence that ochratoxin levels are reduced, is awaited.

2 Grain sniffer

An electronic nose could soon help farmers combat outbreaks of grain store mould before grain quality is threatened. It could also be used by the grain trade to accept or reject sub-standard grain.

Based on similar technology to the sniffer designed to detect rots in potato stores, the hand-held device will detect very low levels of mould, distinguishing between different species and possibly helping combat mycotoxin, says project leader Helen Brown of CCFRA.

A prototype is due for evaluation next year ahead of possible commercial launch in 2001 for as little as £100. Manufacturer Protimeter is showing keen interest.

3 New pest traps

Detecting grain store pests is set to become a lot easier thanks to the development of new traps by CSL.

To replace bait bags and improve the efficacy of PC traps, a new generation of PC trap containing either insect-attracting pheromones or food extracts is planned. The latter is favoured for its broad-spectrum appeal to grain bugs.

The new traps avoid the problem of unchecked bait bags acting as a focus for insect infestation and the risk of bait bags getting into the food chain, says Ken Wildey of CSL York. New traps should be available in six months, priced to be competitive with existing traps.

4 OPs at risk

Organophosphate grain store insecticides are under extreme pressure, warns CSLs Ken Wildey. US regulators are already adding up all the individual risks of using OP and carbamate products throughout the production chain during re-registration. Furthermore, a 10 times safety factor is applied and then a further ten times safety factor for children. "The future for OP insecticides is going to be very rocky indeed," Dr Wildey comments.

5 Fungi kill bugs

Setting fungus to kill grain store bugs is the latest idea from CSL scientists. Insect-specific fungi, which are naturally occuring and have no effect on humans are being looked at as a method of providing on-going, long-term control of residual insect infestations in stores.

6 Heat damage detector

Grain buyers could soon be using a novel test to detect even the lowest levels of heat damage in grain destined for bread, biscuit and even export markets.

The test, developed by scientists at CCFRA, can detect levels of heat damage well below the 10% of grains that can cause big problems for breadmaking. The so-called Turbidity test takes 15 minutes and uses existing intake-lab equipment to spot even low levels of hard or soft grain that have been heated above the recommended 65C.

7 Mycotoxin alert

Mycotoxin contamination of grain caused by storage moulds is set to become a big issue for grain users.

Although surveys suggest 2-3% of UK grain contain significant levels of the main culprit, ochratoxin A, the good news is that problems can be avoided, even in ambient-air dried bulk stores, provided they are well managed.

UK food regulations already require grain users to minimise levels of the toxic carcinogen in grain for food use. Tighter EU limits are expected in two to three years.

But provided grain is dried to below 16% moisture within 14-28 days even on-floor bulk drying with ambient air or backlogged grain awaiting high temperature batch drying need not run into trouble, says independent storage consultant Keith Scudamore. Faster drying and lower grain temperatures help further.

A study post-harvest 1998 shows what can happen when things go wrong. Late, wet harvesting meant grain entered an on-floor bulk store with ambient ventilation at 22% moisture. Only after a month did the surface layer show any sign of drying and it was four months before it was down to 17% moisture.

That resulted in mould production and an ochratoxin A content of 5.9µg/g, above the expected 5µg/g EU limit. Fortunately the grain temperature was just 5-7C. Any warmer and ochratoxin levels could have been far higher, Mr Scudamore warns. &#42


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