All About Potato: From a Rocky Start to Everyone’s Heart
Once again, the basket of french-fired potatoes was sent back to the kitchen, the customer arguing they were still too thick. With great frustration, he again began by slicing fresh potatoes, but this time as thin as he could before frying them and ordering them to be sent back to the waiting guest.
So goes the legend of George Crum, the chef who in 1853 invented perhaps the worlds most favourite snack – the chip/crisp. As a staple crop with 55 million metric tonnes produced in Europe alone, it may be difficult to imagine the scepticism first held by Europeans towards the potato.
Native to South America, potatoes were first grown in the Peruvian-Bolivian Andes mountain range. The earliest cultivators of this crop are believed to have been the Incas about 1800 years ago. From its first cultivation, the potato became an everyday staple food for the tribe and was believed to hold other properties. Using the extreme cold temperatures possible in the Andes mountains, the Incas would freeze-dry their potatoes by leaving them out in the cold. Once frozen, they could be crushed into a powder called ‘chuñu’. Chuñu could be applied as a treatment for almost everything from stomach ulcers to a type of Andean wart and even syphilis. From South America, the potato made its way to Europe in the 1600 century via the Spanish invasion. Here this new crop met with great scepticism for several reasons.
The environmental conditions that the potatoes were used to in the Andes were much different from their new home in Europe. In the regions around the equator, the length of daylight is relatively consistent throughout the year, and the potato varieties the Spaniards brought were used to 12 hours of light per day. Southern European summery days offered the potatoes more light than that which student their growth. Instead, the plants preferred the light intensity in the autumn. The plants could not survive with their growing period too close to when early winter frost sets in. However, the cultivation of potatoes in northern Europe, more specifically Ireland, was more successful. The Irish autumn brought about much more favourable growing conditions for the new crop without the early onset of frost that would kill the plants. Sir Walter Raleigh was the explorer that first brought the potato to Ireland and is said to have gifted it to Queen Elizabeth I, ruler of Great Britain at the time. She, in turn, ordered a potato banquet where each meal should contain this new wonderful crop. Unfortunately, due to their inexperience with preparing potatoes, the royal kitchen included the leaves and stems in their dishes. These, however, contain a potent toxin called solanine, making them poisonous, causing symptoms such as vomiting and abdominal pain. With the dinner attendants becoming incredibly ill, Queen Elizabeth I banned the crop.
At the beginning of the 1800 hundreds, it had been established that the tubers (which we refer to as potato) are perfectly safe to eat, and the Irish had taken a particular liking to them. Under British rule, much of the good and nutrient-rich land was owned by England. Left with poor soil and having to pay fees for renting their lands, growing potatoes improved their lives, at least for a while. Compared to other crops available to them, potatoes grow well in relatively poor soil and contain higher nutrition levels. They are a great source of Vitamin C and protein. However, the potatoes grown by the Irish were only propagated vegetatively (asexually). With only one strain of potato available, all potatoes grown were identical copies of each other. The potatoes’ lack of genetic variation became the underlying cause of the 15 year Irish Potato Famine between 1845 and 1860. The summer of 1845 turned out to be much cooler and wetter than what is usually the case, the perfect conditions for Potato Late Blight Fungus. Still considered among the most threatening pathogens of potato today, it has a devastating impact on yield. The exact combination of symptoms shown by infected plants vary, but leaves begin by showing small irregular green or grey spots on them. These spots quickly turn into lesions, now black in colour. From there, the fungus spread into the stem of the plant and down to the potato. Depending on the growth stage of the potato tuber, generally giving the skin a brown to purple colour. In young potatoes, the site of infection may appear to be dark brown to red. Due to a better understanding of plants, diseases and their prevention of famines like this can more easily be avoided. As mentioned in previous posts, time is of the essence when it comes to disease management and prevention, and the Irish famine is a great example of this. Once the virus had set in, it did not take much longer than 1-week before creating irreversible damage to the livelihood of the Irish. Similarly, for farmers that cultivate traditionally nutrient-deficient soil, proper fertilisation helps increase yield and the quality of the crops and their ability to withstand pathogens. Precision farming is the perfect aid for determining how much and what kind of fertilizer the plants require. Similarly, if a pathogen attack was to threaten the yields of a field, precision farming is able to detect it much earlier than the human eye. Thus, farmers knowing their plants and their needs are the cornerstone to preventing and mitigating the devastating impact of famines.
How are potatoes grown?
Potatoes can be grown from two different kinds of “seeds”. The most common method that usually first comes to mind is growing a new potato plant from ‘seed potatoes’. For example, this is the method used by the Irish back in 1800-hundreds and develops a new plant identical to the original one that produced the potato tuber used. Since these “old” potatoes are the foundation for the new plant and crops, the tubers health is essential. Seed potatoes should ideally weigh between 30-40 grams each, be disease-free and already have begun sprouting. Though they come at higher costs, commercially available seeds can increase a farmers yield between 30-50% compared to using their own seeds. Correct irrigation is important to be maintained even in potato plants, but specific periods have a more significant impact. For example, it has been found that drought early on in crop development does not have as big of an impact as in the middle, where it causes substantial yield loss. Potatoes can also be grown from traditional seeds. Potatoes are flowering plants with rich greenery growing above the ground where also the small green looking berries containing the seeds can be found.
At the time of plantation, the seed potatoes are placed between 5-10cm deep into the soil. It is common to see the rows of potato fields with hills stretching over where the seeds have been placed. In areas where drought is common, and rain is the primary source of irrigation, it is recommended to plant the crop on flat soil. This allows greater water retention, which in turn improves crop growth and yield. The so-called plant canopy (above-ground part of the plant) develops for about four weeks after plantation. During this period, farmers must take extra care to remove all weeds, which otherwise would steal the nutrition from the growing potato. A common method to help reduce the growth of weeds and discourage pests from making their way to the plant is ridging. Using a tractor with plough like attachments, the soil between the rows is carved and pushed towards the plants, loosening it. In addition to manually removing weeds or applying pesticides, farmers can use ridging on several occasions during the growing period. The earliest time is when the plants are between 15-20cm high. Later on, in the season, this method can also be used to cover the growing tubers. When potatoes are exposed to sunlight, they begin to turn green in colour. These spots have a bitter taste and also contain the toxin solanine. Potato plants can produce from a handful to over 20 potatoes each, weighing between 300g-1.5kg. The heaviest potato as recorded by Guinness World Records was a staggering 4.95 kg.
How are potatoes harvested?
Irrespective of the variety of potato grown, a good indicator of the tubers ripeness can be seen on the now wilted plant above the ground. When the plant has turned yellow, and the stem is easily removed, the farmers can begin harvesting. For easier harvesting, the wilted above-ground part of the potato plant should be removed ca 2 weeks prior. When it comes to harvesting equipment, farmers have 3 varieties to chose between. First, the spading fork, given by its name looks like a giant fork that can be used for manual harvesting. Here farmers dig into the soil and sieve out the potatoes from the soil. Second, farmers can also use a tractor with a plough attachment to dig the potatoes out of the ground. The third and most convenient alternative is using a potato harvester. This tractor lifts the potatoes and some of the soil out of the ground. The potato and soil are then transferred via a conveyor belt, where they are separated from one another. The potatoes are then passed on to a truck or other container driving next to the harvester.
If the farmers know that the potatoes will be stored for an extended period before further processing or consumption, they can leave the potatoes in the soil for a while longer. This makes the potatoes grow thicker skin which acts as a protective barrier. This makes them less vulnerable to diseases while contained in storage but also limits water loss which otherwise causes them to shrink. The ideal storage conditions for potatoes are a room temperature between 6-8°C with 85-90% air moisture and complete darkness.
Sweet potatoes are not true potatoes.
And true potatoes are not root fruits. There are hundreds of varieties of potato differing in flavour, colour and shape. Their use cases are equally many, from making the perfect Italian Gnocci to comforting potato mash. Yet, the perhaps most loved potato is an impostor of the most delicious kind. True potatoes belong to the family called Nightshade, while sweet potato belongs to the family Morning Glory. Though they, at first glance, may appear to be very similar their functions are different. Potatoes/tubers are a kind of extra thick stem extended underground. They store much of the plant’s nutrition for safekeeping and be used in the next year’s growing season where a new plant can emerge. Sweet potatoes, on the other hand (though they also grow in soil) are modified roots, not stems.
Though they were off to a difficult start, potatoes are a fantastic crop with use-cases across cultures and cuisines that makes the long journey from the New World to our hearts worth it.
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