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Potatoes

Potatoes are a bit like a dependable old friend. They are always there for you. Whether it’s a plate of home-made chips, an oozing gratin or a buttery potato purée, potatoes offer solace and comfort. You can snuggle up with them like a warm quilt. Too often used in a routine way as a ubiquitous, stodgy sidekick to the main act, potatoes have patrician potential and can rise to the special occasion when cooked thoughtfully and creatively.

For cooks, the crucial distinction in potato type is between waxy (firm flesh, good for salads) and floury (more granular, good for roasting and mash), although some varieties (Desiree, Wilja, Romano) fall between these two categories. The mainstream potato industry grades potatoes on a scale from one (waxy) to nine (floury), but most commercial effort goes into developing and marketing a few ‘all-purpose’ varieties.

The flavour and texture of potatoes come down to a combination of the variety grown and the growing method, but even the best grower can’t make duff varieties taste of much. Our shelves are loaded with potatoes that look the part, but disappoint on the flavour and texture front. Under the influence of supermarkets, plant breeders have developed potatoes for yield, processing quality and appearance. They must be free from deep-set ‘eyes’, all similarly shaped, and have no knobbly bits, which instantly knocks out many of our distinguished traditional varieties. Eating quality has barely entered the brief. Old varieties (see Potatoes with a sense of place), prized for their flavour, their flesh of various colours and their distinctive textures, have lost out to anonymous-tasting, white-fleshed modern varieties, such as Maris Piper, Santé, Estima, Cara, Rocket and Nadine, that produce high yields when given lots of water and chemical fertilizers.

If you want real spuds, not duds, then seek out varieties with character and personality. Among the most readily available, the best-tasting waxy varieties include Charlotte, Nicola, Jersey Royal, Pink Fir Apple, Yukon Gold and La Ratte; the best-tasting floury varieties include Golden Wonder, Marfona, King Edward, Duke of York, Valor, Cosmos and Kerr’s Pinks.

Things to do with potatoes

• Roast unpeeled potato wedges in olive oil and generously dust just before serving with smoked paprika and sea salt.

• Vary the classic gratin Dauphinois (thin slices of floury potatoes baked with cream, nutmeg and garlic) by substituting turnip, Jerusalem artichoke, celeriac or parsnip for half the potatoes.

• Greek skordalia – smooth potato, garlic and olive oil purée – served warm makes an unusual dip to serve with crudités.

• A couple of finely chopped anchovies turns a basic, creamy gratin into that full-bodied Scandinavian dish, Janssen’s temptation.

• For a cheap, but interesting starter, purée potatoes with olive oil and a little poached salt cod to make a French brandade. Serve with rustic toast brushed with olive oil.

• Thinly sliced potatoes and onions baked with stock – pommes Anna – make a lighter gratin.

• Home-made potato gnocchi beat the ready-made vacuum-packed sort hands down.

• Instead of the usual mayonnaise approach, make a more Germanic potato salad by dressing still-warm waxy potatoes with oil, wine or cider vinegar and lots of smooth mustard, then add fresh dill and chopped gherkins. Serve with crisp lardons of bacon on top, or with ham or smoked meats.

• Grate par-boiled waxy potatoes, season well with sea salt and pepper and shallow fry in thin, flat piles to make crunchy Swiss rosti.

Are potatoes good for me?

Potatoes are best thought of as a starchy carbohydrate food, an alternative to rice or pasta, rather than as a vegetable. Potatoes do contain some vitamin C, which supports the immune system, and this makes them nutritionally preferable to other popular starchy foods like couscous, pasta and white rice. Vitamin C levels are higher in new potatoes (the thin-skinned sort) than in older potatoes (the thicker-skinned sort). They also contain useful amounts of vitamin B6, which is necessary for metabolizing the amino acids in protein and the formation of red blood cells; vitamin B1, which is needed for healing and the smooth running of the nervous system; iron, which helps prevent anaemia; and folate, which helps prevent birth defects.

Like other starchy foods, potatoes do release sugar rather rapidly into the blood and this can encourage a surge in the fat storage hormone, insulin, which encourages the body to lay down fat. Different types of potatoes affect insulin in different ways. New potatoes raise your blood sugar level less than older, maincrop potatoes. Older maincrop potatoes are not great for people who want to lose weight, despite all those diet sheets that seek to persuade us that a baked potato is the slimmer’s friend. That said, if you eat potatoes along with foods that contain protein and fat, like meat, fish and eggs, this significantly slows down the release of sugar into the bloodstream.

In the past there have been concerns about residues of pesticides in potatoes, mainly in new potatoes. In recent years, the situation seems to have improved with around two-thirds of potatoes sampled in government tests coming up residue-free. More progressive conventional growers use ethylene gas to protect the potatoes in cold storage, rather than spraying them with post-harvest chemicals. You can reduce your exposure to chemical residues by choosing organic potatoes. One pesticide can be used in organic potato growing, but only in extremely restricted circumstances.

How are potatoes grown?

Potatoes are planted outdoors in rows, and the soil is mounded up around the emerging leaves to encourage the tubers to grow. Organic growers approach the challenge of growing potatoes without pesticides by choosing varieties that are less susceptible to disease, such as Valor, Nicola, Cosmos, Desiree, Charlotte, Raja and Saxon, and, increasingly, by growing the new, blight-resistant organic varieties that are being developed. Instead of using chemical fertilizers, they grow potatoes in long rotations, interspersing them with other crops. Organic potatoes are often planted after a crop such as red clover, that naturally fertilizes the soil, and the soil is then dressed with manure. Jersey Royals, though not organic, are treated with a natural seaweed fertilizer called ‘vraic’.

Most older potato varieties are very prone to blight (see Are potatoes a green choice?), so although they can be grown organically on a back-garden scale, they are susceptible to crop failure when cultivated on a more commercial scale.

Are potatoes a green choice?

An underlying problem with potatoes is their narrow genetic base. There are some 150 different species of potatoes in the Andes where the potato family originates, but all the potatoes grown outside that region come from one sub-species. This lack of biodiversity, or genetic similarity, leaves the world’s crop more susceptible to disease, in particular, blight, the same devastating fungus that caused the Irish potato famine of the 1840s and which destroys 20 per cent of the world’s annual potato harvest.

One solution advanced for blight is genetic modification, but this is extremely controversial. The leading International Potato Centre in Lima, Peru, has imposed a moratorium on planting GM potatoes in South America because of fears that genes introduced into GM potatoes might escape into wild potatoes. Meanwhile, plant breeders in Hungary and Scotland have already come up with a non-GM solution, successfully breeding blight-resistant new varieties, such as the organic Sarpo Mira and Axona, using conventional breeding techniques. These new organic varieties have shown unprecedented blight resistance and also virus resistance, while other supposedly blight-resistant varieties, such as the ubiquitous Sante and Cara, have been wiped out within weeks. Biotech evangelists love to make out that only their industry has the solutions to intractable farming problems like blight, but here’s a glowing example of how it is possible to breed a crop with a desirable trait without using highly unpredictable GM techniques, such as the introduction of antibiotic resistance marker genes, that open the door to major environmental and health risks.

POTATOES WITH A SENSE OF PLACE

For as long as anyone can remember, the potato has been a stalwart ingredient in the British and Irish diet. Back in the Second World War, it was considered such an essential, healthy food that potato growing became a key plank in the British strategy for survival. It figured prominently in the Ministry of Food’s ‘Dig For Victory’ campaign, which enlisted a cartoon superhero, Potato Pete, to encourage the nation to grow and eat more potatoes, successfully doubling the acreage planted. Nowadays, only the Portuguese and the Irish eat more than we do.

Potatoes grow quite well in our climate and Britain has always been a leading centre of expertise in potato cultivation and breeding. Some rare, traditional potato varieties are still in small-scale commercial production, popular with allotment holders and gardeners and very much in vogue with chefs. Taste them blind, and the taste contrast with the standard spuds we eat is striking. They look discernibly different too. Some have deep-set eyes, others thick, netted skin – like the scruffy East End cousins of cosmetic modern varieties. Their skin tones employ a palette of colour from mercury black through rosy pink to midnight blue. Their flesh can be alabaster white, butter yellow, imperial purple, indigo or claret. Their shapes go from elongated and knobbly via oval to round and smooth. Their names have all the interest of a Grand National line-up: Highland Burgundy, Kepplestone Kidney, British Queen, Edzell Blue, Red Duke of York, Purple-Eyed Seeding, Epicure, Shetland Black, La Ratte, Peachbloom, Pink Fir Apple, Red King Edward, Witchill and Mr Little’s Yetholm Gypsy, to mention a few. These are potatoes steeped in history and traditions, potatoes with a sense of place.

Where and when should I buy potatoes?

The potato year begins with the arrival of ‘new’ or ‘early’ potatoes. They are lifted young when they still have thin skins that can be rubbed off with the fingers and their consistency is slightly waxy. In February, imports from Egypt, Israel and Cyprus start arriving in shops, followed by Jersey Royals in March then Cornish and Ayrshire varieties in May and June. If you want to reduce unnecessary food miles, then stick with UK new potatoes: they are worth waiting for. Next come the ‘second earlies’ grown in colder, more frost-prone areas of the UK, followed by early ‘maincrop’ potatoes in August, then the true maincrop potatoes that come on stream in September and October. These maincrop potatoes have a higher dry matter content than earlies and thicker skins. They can be sold directly from the field or kept in cold storage throughout the winter to preserve them until the next year’s home-grown new potatoes become available.

Supermarkets are now stocking a few more interesting ‘heritage’ varieties, but for a better range check out specialist potato suppliers and look out for more unusual, characterful varieties at farmers’ markets.

Will potatoes break the bank?

In early spring, before the new season’s Irish- or UK-grown potatoes are available, imported new potatoes go on sale. These can make the maincrop potatoes from the season before look rather old, but they will still be fine for most purposes – they just need to be peeled – and will cost a fraction of the price commanded by the new, more attractive-looking imports.

You pay an awful lot for the privilege of having your potatoes pre-prepared. Products such as ready-made gratin, baked potatoes and fried wedges come with a huge mark-up. Save a small fortune by making your own at home. And, of course, they will taste better.

Don’t throw away older potatoes when they start sprouting. This happens naturally when maincrop potatoes are stored over winter. Just knock off the sprout and use the rest of the potato. Don’t use potatoes with large green areas, as these have been exposed to light and could be slightly poisonous. It’s fine, however, to eat potatoes with only a little patch of green on them. Simply cut it off.