Just when you think nothing can surprise, up pops something and it made me giggle, laugh out loud and chuckle with mirth. Thinking of a day out? Then what about a trip with the ‘Yorkshire Forced Rhubarb Forcing Shed Tours’. I could not make this up. I would not even try. No one would believe me. But behind this bit of frippery there lies a very serious set of scientific principles, a long lasting tradition (since 1877) and a deserved pride in a highly valued culinary product.
Wild rhubarb’s origins are in Northern Asia, and its use has, not without controversy, been traced back about 5000 years (J. L. Capinera, Handbook of Vegetable Pests 2020). It is native to China and belongs to the Rheum L. genus from the Polygonaceae family. It was known in Classical Greece and Rome as an imported dried root with medicianal qualities (Oxford Companion to Food, p680). Botanically, it is a vegetable although classified as a fruit in 1947 by the US Customs Court of New York, some say because the tax was lower on fruits and other say because it was already eaten as a fruit.
Rhubarb thrives where summers are cool. Britain, the Netherlands, Germany, the Nordic countries, Canada, and the USA are the main commercial regions of cultivation. Rhubarb is one of the few perennial vegetable plants that is cultivated as a perennial. It is grown primarily for its fleshy sticks or stalks. In temperate climates rhubarb is one of the first food plants to be ready for harvest, usually in mid to late spring, and lasts until September (M.Clementi & F.Misiti, 2010). The color of the rhubarb stalks can vary from the commonly associated deep red, through speckled pink, to simply green. The color is not related to its suitability for cooking. The green-stalked rhubarb is more robust and has a higher yield, and the red-colored stalks are more popular with consumers.
Rhubarb has long been used as an antibacterial, anti-inflammatory, anti-fibrotic and anticancer medicine in China where its application can be traced back to 270 BC in “Shen Nong Ben Cao Jing” (a Chinese book on agriculture and medicinal plants), and where it was traded as a medicinal herb as early as the 16th century. It is still used widely in Chinese medicine. Modern Chinese medicine cites, for instance, 27 studies looking at rhubarb’s role in the control of sepsis. However, while research on Asian rhubarb has made great progress in recent years it is also acknowledged that more systematic research is needed which could allow the specification of for instance benificial species of rhubarb, the mechanisms underlying rhubarb hepatotoxicity or even its use as a ‘promising medicine for cancer chemoprevention’ (K.Z.Masoodi et al, in Biodiversity and Biomedicine, 2020). H.Xiang, et al, (2020), in their article ‘What we already know about rhubarb’ conclude that more scientific, rigorous and extensive clinical trials are needed to gain firm insight.
The differentiation of Asian medicinal rhubarb from other fruits and particularly from other varieties of rhubarb containing polyphenols has been overlooked it is said. Work at Sheffiled Hallam University’s Biomedical Research Centre (2018) suggests that the specific polyphenol found in English garden rhubarb has “great anti-cancerous potential” that could lead to the development of new cancer treatments. Dr Nikki Jordan-Mahy, from Sheffield Hallam University’s Biomedical Research Centre, said: “Our research has shown that British rhubarb is a potential source of pharmacological agents that may be used to develop new anti-cancerous drugs. Current treatments are not effective in all cancers and resistance is a common problem. Cancer affects one in three individuals in the UK so it’s very important to discover novel, less toxic, treatments, which can overcome resistance.”
Rhubarb recipes in England began to appear in the early nineteenth century, perhaps when sugar as a commodity began to be more freely available. And it is here we return to Yorkshire and the forcing of rhubarb.
Yorkshire soil is excellent for growing rhubarb. It’s a high water-retaining soil, it gets very cold in winter and the water takes the cold right down to the root. It also has a deep top soil, full of nutrients which is perfect for rhubarb. Yorkshire is famous for the quality of its rhubarb. The Rhubarb Triangle, established in 1877, is known as the centre of the world for forced rhubarb, it’s formed by three areas in West Yorkshire which all meet at a point – Leeds, Wakefield and Bradford. In Feb 2010, Yorkshire Forced Rhubarb was awarded Protected Designation of Origin (PDO) status by the European Commission. To be called Yorkshire Forced Rhubarb it must be produced in this nine-square-mile area. Where once there were over 200 producers now only 12 firms produce this rhubarb.
The forced roots are grown outdoor in fields for two years where they store energy. The roots need to be given the chance to store energy from the sun before they are transported into the forcing sheds.The roots are delicately transported to the beds inside the forcing sheds. A root can sometimes take up to 3 people to lift onto the trailers! The sheds are kept in darkness and the rhubarb is harvested by candlelight to stop photosynthesis from occurring as this thickens and toughens the fibres and results in an acidic flavour.
Lonra Parkes says, “Today, forced rhubarb is considered the king of rhubarb by those in the know. Top chefs covet this curious crop for its superior taste, which is not as sharp as summer rhubarb, and its tenderness. Forced rhubarb is also highly desirable because of its bright pink or red skin (the colour depends on the variety), which absorbs into the blanched white flesh during cooking and looks strikingly pretty on the restaurant plate”. The Yorkshire Society has written an excellent article, Leeds: the centre of forced rhubarb production.
And here is a plug for the Yorkshire Rhubarb Forcing Shed in Lofthouse where it is possible to tour the shed, learn the history of rhubarb, hear some stories, see some ‘rhubarb growing indoors, in complete darkness and out of season. If you listen close enough you might just hear the rhubarb growing!’ (Visit Leeds) Tours are 1hr 45 min and run from January to March.
The stalks of all varieties can be cooked in lots of ways. Stewed, they yield a tart sauce that can be eaten with sugar and stewed fruit or used as filling for pies, tarts, and crumbles. This common use has led to the slang term for rhubarb, ‘pie plant.’ It can be cooked with strawberries or apples as a sweetener, or with stem or root ginger, rhubarb makes excellent jam. It can also be used to make wine and as an ingredient in baked goods. But today the recipe will be for Rhubarb Chutney, simply because I have just made some. The recipe comes from the excellent book ‘The complete book of Small-Batch Preserving‘, by Ellie Topp & Margaret Howard, 2nd ed 2013, where it is called Rhubard, Date and Apricot Chutney and is sooo good.
