Quality the top
processing priority – for now…
WHEN it comes to processing, tuber quality has to come before agronomic advantages. Tighter processor specifications are ringing the variety changes in the sector, but the next generation could have grower benefits too.
"The first priority must always be processing quality, everything else is secondary," says Tom Dixon, technical director for the Beeson Group. Good agronomic characteristics are just a bonus for growers, he says.
Within the processing sector, crisps are the boom product, expanding at 2-4% a year, now taking 25% of the UK potato crop. Buyer demands have thrown variety choices into turmoil.
"Until a few years ago Record had 90% of the market, but after a change of specifications needed for a paler and more consistent fry colour it has almost disappeared to be replaced by Lady Rosetta, Hermes, and Saturna," says Mr Dixon.
That point is echoed by Simon Kerr of the National Institute of Agricultural Botany. "The phenomenal decline of Record has caused a lot of upheaval. The certified seed area slumped to 283ha last year, from 1248ha in 1994. That is because it no longer meets the fry colour specification or has the taste and texture demanded for todays market."
Two new maincrop types, Sunbeam and Midas, gained NIAB recommendation in 1998, and look set to take some market share, reckons Mr Kerr.
"Both have potential for crisping. Sunbeam has no major weaknesses and Midas combines very good blight resistance with dual nematode resistance."
That could be particularly useful in crops grown near factories in tight rotations, notes Mr Kerr, as few processing types have in-built protection. Russet Burbank, Shepody and Dell are all susceptible, whereas Sunbeam has Globodera rostochiensis resistance and Midas combines G.rostochiensis resistance with moderate resistance to Globodera pallida. It is the only processing type with double-barrelled protection.
Lady Rosetta, a Dutch-bred red maincrop, gives good marketable yields early in the season and can be stored. The high yielding Austrian-bred Hermes throws a bold sample of oval yellow tubers combining crisping quality specifications with worthwhile agronomic benefits.
Saturna is particularly suitable for long-term storage as it does not suffer sugar accumulation, adds Mr Dixon.
Of the new candidates for crisping, Mr Dixon reckons coded types from US breeder Fritolay show potential, as well as Lady Clare and Silvester.
Mr Kerr agrees that the US-bred coded types look interesting. FL 1833 and RD 90/325/10 are maincrops with tubers well suited to modern crisping markets, but yield less than Record in the UK.
Also promising is another coded type from Nickersons, the French-bred 355/85/2. It gives a better yield than Record of high dry matter tubers which fry well.
US-bred Atlantic is also a potential crisper, and is widely grown around the world. However, it is susceptible to virus Y, blight and spraing, and can be prone to splitting under UK conditions, notes Mr Dixon.
For french fries Mr Kerr believes the Scottish-bred parti-coloured Spey looks promising for maincrop use, with Velox for the early production slot to challenge Premiere.
Spey produces a high yield of long, oval white tubers with pink eyes and cream flesh which fry well, with a uniform pale colour. Although late maturing and susceptible to virus Y and spraing, it has good resistance to G.rostochiensis and is partly resistant to G.pallida.
German-bred Velox, in its second year of NIAB trials, is early maturing with long oval tubers with similar fry colour to Premiere. It is the only first early which combines sufficiently high dry matters with the required fry colour.
Erntestolz and Karlina, also German varieties, have caught NIABs eye for the expanding valued added processing market of products such as waffles and hash browns.
"And no-one should ignore the fish and chip shop trade which takes 600,000t of fresh potatoes a year. This cheap and cheerful but important market is dominated by Maris Piper, but Morene is also used widely and Navan fries well. Spey and Caesar could be used in future," says Mr Kerr.
Despite processors starting to follow the supermarkets interest in lower input varieties, Mr Dixon is adamant processing quality will remain their number one requirement.
"Thats why one leading burger chain still insists its french fries are made from the 100 year old US variety Russet Burbank, even though it is not easy to grow." As a result, Burbank dominates the high-value french fry sector, and accounts for 3-4% of the total UK potato crop.
Canadian-bred Shepody is an alternative for Burbank in early season, producing moderate yields of long oval tubers with high dry matters.
Morene is already being grown, but other contenders include Spey and Santana.
Although the market for fries is growing, there is still solid demand for freezer chips. This is met mainly with Pentland Dell, plus Maris Piper and Desiree.
There are few obvious replacements to these, but Cycloon and Viking seem possible candidates, he concludes.
Processing quality paramount
Agronomic benefits bonus only
Burbank to stay for french fries
Midas touch – double-barrel PCN resistance for crisps
• Processing quality paramount
• Agronomic benefits bonus only
• Crispers booming
• Burbank to stay for french fries
• Midas touch – double-barrel PCN resistance for crisps