Potatoes - storage and processing
Practical Action
cooking the potatoes to gelatinise the starch and
make them more digestible. Most potato dishes are
served hot and they include unpeeled baked potatoes;
boiled or steamed potatoes; peeled roast potatoes;
mashed potatoes from peeled boiled potatoes with
milk, yoghurt and/or butter, also used a component of
traditional dishes such as shepherd's pie, fish pie,
and Colcannon or ‘bubble and squeak’ (mashed
potato fried with a shredded leafy vegetable); hash
browns (grated into small thin strips and fried). Boxty
pancakes are traditionally made with soaked grated
potatoes mixed with flour, buttermilk and baking
Fig. 3. Papa rellena - a South
powder. Acadian poutine is a ball of grated and
American potato product (from
mashed potato, salted, sometimes filled with pork,
http://en.wikipedia.org/wiki/Papa_r
and boiled. In India, potato is used in Aloo ki sabzi
ellena) Peruvian stuffed potatoes
(potato curry), alu paratha, a type of stuffed
are mashed potatoes that are
chapatti, and in puri snacks. Masala dosa is a thin
shaped around a center of
pancake of rice and pulse paste with spicy mashed
seasoned ground beef and then
potato filling. Other dishes are alu tikki and pakodas. fried golden brown.
South American cuisine contains potatoes as a main
ingredient in many dishes (e.g. Fig. 3), often with chilli-based sauces (papa a la huancaina), or
Carapulca with dried potato (papa seca). Bryndzové halušky in Slovakia is made of a batter of
flour and finely grated potatoes boiled to form dumplings. Puddings (kugel, kugelis and potato
babka) are made from grated potatoes in Lithuania and Belarus. Mashed potatoes or potato
flour are used in dumplings eaten with meat dishes throughout central and eastern Europe and
in Italy potatoes are used to make a type of pasta named gnocchi.
One of the most important derivatives of the potato in Peru is the dried potato known as Papa
Seca, a product that requires little preparation. Soluciones Practicas has written about the
processing of Papa Seca.
Potato flour is made in some countries by grinding potatoes to a paste and drying and milling
it to the flour. Chuño is freeze-dried potato, traditionally produced in mountainous regions of
Peru and Bolivia, where the low temperatures and low air pressure allow the process to take
place naturally. In other areas, freeze drying requires equipment and this process is too
expensive.
Frying
The most widespread type of potato processing that is used by small-scale processors is frying
and the two most common products are potato chips (or ‘French fries’ in USA) and potato
crisps (or ‘chips’ in USA). These products are made from peeled potatoes that are cut into
slices or scallops and fried. Other fried potato products include aloo chaat; patatas bravas, a
dish of fried potatoes in a spicy tomato sauce; potato samosas made from spicy mashed potato
mixed with vegetables, stuffed into dough and deep fried. Each of these products offer the
opportunity to add considerable value to basic ingredients using relatively inexpensive
equipment, and as a result frying is a popular and potentially profitable business at all scales
of operation.
Potatoes first require cleaning by soaking them in water to remove soil, and then sorting and
peeling. Potatoes can be sorted according to differences in density by flotation in brine that
has a specific gravity of 1.1162–1.1362. Potatoes that are suitable for crisp-making have
high solids content, which makes them denser and they sink in the brine, whereas less dense
potatoes float. For economical peeling, potatoes should have a uniform oval or round shape
without any protuberances. Peeling by hand is laborious and time-consuming, and causes
excessive loss of potato along with the skins. Machine peeling is preferable in even micro-scale
operations, and the most common type of peeler is an abrasion peeler (Fig. 4). This has a
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