Nancy J Pollock. Cambridge World History of Food. Editor: Kenneth F Kiple & Kriemhild Conee Ornelas. Volume 1. Cambridge, UK: Cambridge University Press, 2000.
Taro is the common name of four different root crops that are widely consumed in tropical areas around the world. Taro is especially valued for its starch granules, which are easily digested through the bloodstream, thus making it an ideal food for babies, elderly persons, and those with digestive problems. It is grown by vegetative propagation (asexual reproduction), so its spread around the world has been due to human intervention. But its production is restricted to the humid tropics, and its availability is restricted by its susceptibility to damage in transport.
Taro is most widely consumed in societies throughout the Pacific, where it has been a staple for probably 3,000 to 4,000 years. But it is also used extensively in India, Thailand, the Philippines, and Southeast Asia, as well as in the Caribbean and parts of tropical West Africa and Madagascar (see Mur-dock 1960; Petterson 1977). Moreover, in the last quarter of the twentieth century taro entered metropolitan areas such as Auckland, Wellington, Sydney, and Los Angeles, where it is purchased by migrants from Samoa and other Pacific Island nations who desire to maintain access to their traditional foods (Pollock 1992).
Although taro is the generic Austronesian term for four different roots, true taro is known botanically as Colocasia esculenta, or Colocasia antiquorum in some of the older literature. We will refer to it here as Colocasia taro. False taro, or giant taro, is the name applied to the plant known botanically as Alocasia macrorrhiza. It is less widely used unless other root staples are in short supply. We will refer to it as Alocasia taro.
Giant swamp taro is the name used for the plant known as Cyrtosperma chamissonis. This is a staple crop on some atolls, such as Kiribati, and is also grown in low-lying areas of larger islands. We will refer to it as Cyrtosperma taro. The fourth form of taro has been introduced into the Pacific and elsewhere much more recently. It is commonly known as tannia, kongkong, or American taro, but its botanical name is Xanthosoma sagittifolium. It has become widely adopted because it thrives in poorer soils and yields an acceptable food supply. We will refer to it as Xanthosoma taro.
The starch-bearing root, termed corm or cormlet, of these four plants makes a major contribution to the human diet, and even the leaves are occasionally used as food, as in the case of young Colocasia leaves. The leaves are also employed as coverings for earth ovens and as wrappings for puddings that are made from the grated starch root and baked in an earth oven. The large leaves of Cyrtosperma taro also provide a good substitute for an umbrella.
Botanical Features
All the taros are aroids of the Araceae family, so we would expect to find close similarities among them. They grow in tropical climates with an adequate year-round rainfall. All taros must be propagated vegetatively, as they do not have viable seeds. Consequently their production for food crops has been engineered by human intervention. Both the corms and the leaves are acrid to some degree, particularly before they are cooked, and cause an unpleasant irritation of the skin and mouth (Tang and Sakai 1983; Bradbury and Holloway 1988).
Colocasia Taro
The Colocasia taro plant consists of an enlarged root or corm, a number of leafstalks, and leaves.The leaves are the main visible feature distinguishing Colocasia from the other taros, particularly Xanthosoma. The Colocasia leaf is peltate, or shield-shaped, with the leafstalk joining the leaf about two-thirds of the way across it. Varieties of Colocasia taro differ in the color of the leafstalk, the shape and color of the leaf and veins, and the number of fully developed leaves. They also differ in the shape, flesh color, and culinary qualities of their tubers. The varieties are recognized by individual names, particularly in those societies in the Pacific where the plant is a major foodstuff. For example, 70 local names were recorded in Hawaii and 67 in Samoa (Massal and Barrau 1956; Lambert 1982). Indeed, fully 722 accessions have been recorded in collections of root crops in South Pacific countries (Bradbury and Holloway 1988).
Colocasia taro can be grown on flooded or irrigated land and on dry land. The planting material consists of the corm plus its leafstalks, minus the leaves. Taros in Fiji are sold this way in the market, so that the purchaser can cut off the root for food and plant the topmost part of the root plus leafstalks, known as a sett, to grow the next crop of taro. Harvesting one taro root therefore yields the planting material for the next crop.The root takes about 7 to 10 months to mature. Once the corm has been cut or damaged, taro rots quickly, making it difficult to ship to distant markets.
Alocasia Taro
Sometimes known as giant taro, or kape in Polynesian languages, Alocasia taro is a large-leafed plant that is grown for its edible stem rather than for the root. The fleshy leaves are spear-shaped and can reach more than a meter in length. The stem and central vein of the leaf form a continuous line.The leaves of this taro are not usually eaten.
The edible part is the large and long (a half meter or more), thickened underground stem that may weigh 20 kilograms (kg). It is peeled and cut into pieces to be cooked in an earth oven or boiled.
Alocasia taros are very acrid, as they contain a high concentration of calcium oxalate crystals in the outer layers of the stem. These crystals are set free by chewing and can cause irritation in the mouth and throat if the stem is not thoroughly cooked. The calcium oxalate content increases if the plant is left in the ground too long. For this reason some societies consider Alocasia taro fit for consumption only in emergencies. But in Tonga, Wallis, and Papua New Guinea, varieties with very low oxalate content have been selectively grown to overcome this problem (Holo and Taumoefolau 1982). Twenty-two accessions are held in collections of root crops for the South Pacific (Bradbury and Holloway 1988).
Cyrtosperma Taro
Cyrtosperma taro, called giant swamp taro, also has very large leaves, sometimes reaching 3 meters in height. In fact, a swamp taro patch towers over those working in it. The leaves are spear-shaped and upright, the central vein forming a continuous line with the stem. The edible corm grows to some 5 kg in size, depending on the variety.
This taro prefers a swampy environment and will withstand a high level of water, provided it is not inundated by seawater. It is grown in Kiribati under cultivation techniques that have been carefully developed over several hundred years (Luomala 1974).
Cyrtosperma taro is a highly regarded foodstuff in Kiribati and in Yap, as well as on other atolls in Micronesia and in the Tuamotus. It is also cultivated in the Rewa district of southeast Fiji, and evidence of its former cultivation can be found in northern Fiji, Futuna, and Wallis, where it is employed today as an emergency crop. It is rarely cultivated outside the Pacific.
Xanthosoma Taro
Xanthosoma taro, by contrast, is much more widespread than Cyrtosperma taro and may be found in many tropical areas, including those on the American and African continents, as well as in the Pacific, where several varieties are now being cultivated (Weightman and Moros 1982). Although it is a very recent introduction to the islands relative to the other three taros, it has become widely accepted as a household crop because it is easy to grow, it can be intercropped with other subsistence foods in a shifting cultivation plot, and it tolerates the shade of a partially cleared forest or of a coconut or pawpaw plantation. It cannot stand waterlogging.
The principal tuber of Xanthosoma is seldom harvested because it also contains calcium oxalate crystals. Rather, the small cormlets are dug up, some being ready 7 to 10 months after planting. These are about the size of a large potato, weighing up to half a kilo.
In appearance Xanthosoma taro is often confused with Colocasia taro, the term “eddoe” being used for both.The main difference between them is in the leaf structure; the Xanthosoma leaf is hastate, an arrow or spearhead shape, and not peltate, so that the leafstalk joins the leaf at the edge, giving it a slightly more erect appearance than the Colocasia leaf. The distinctive feature of the Xanthosoma leaf is its marked vein structure together with a marginal vein.
Production
As already noted, all of the taros must be propagated vegetatively as none of them produce viable seeds naturally. They thus require human intervention both for introduction to a new area and for repeated production of a food supply. This factor further strengthens the likelihood of selection of particular varieties that have more desirable attributes as food, such as reduced acridity and suitability to particular growing conditions. The planting material for all the taros is either a sucker or the sett (consisting of the base of the petioles and a 1-centimeter section from the top of the corm).
Dryland or upland cultivation is the most widespread form of cultivation of Colocasia taro, which grows best in a warm, moist environment. It can be grown between sea level and 1,800 meters (m) where daily average temperatures range between 18 and 27 degrees Celsius (C), with rainfall of about 250 centimeters (cm) annually. The setts or suckers are placed in a hole made with a digging stick, with a recommended spacing between plants of 45 cm by 60 cm to produce good-sized corms. Yield will increase with higher planting density (De La Pena 1983).
Irrigated or wetland Colocasia taro is grown in prepared beds in which, to prevent weed seed germination, water is maintained at a level of 5 cm before planting and during the growth of the setts until the first leaves unfurl. The beds may be a few feet across, beside a stream or well-watered area, or they may be in an area some 2 to 3 acres in size, depending on the land and water available. After the first leaves appear, the beds are frequently covered with whole coconut fronds to shade the young plants from the sun.
Irrigated taro planted at a density of 100,000 plants/ha yields 123.9 tons/ha. With 10,000 plants/ha the yield is 41.4 tons/ha (De La Pena 1983: 169-75). Clearly, the more intense techniques developed for wetland cultivation produce a higher yield. But these techniques are suited only to areas where the right conditions pertain, and on the Pacific Islands such areas are limited because of the nature of the terrain. Dryland taro is, thus, more versatile.
Colocasia taro, whether upland or irrigated, may be harvested after a growing period ranging from 9 to 18 months, depending on the variety and the growing conditions. In Fiji some varieties are harvestable at 9 to 11 months after planting, whereas in Hawaii harvest takes place from 12 to 18 months after planting in the commercial fields.
The subsistence farmer, by contrast, harvests only those taros needed for immediate household use. The farmer will cut off the setts and plant them in a newly cleared area of land or in a different part of the irrigated plot. Thus, any one household will have several taro plots at different stages of growth to maintain a year-round supply and to meet communal obligations for feasts and funerals.
Pests and pathogens are a greater problem for Colocasia taro than for the other varieties. Both the leaves and the corm are subject to damage during the growing period from a range of pests and biotic agents (Mitchell and Maddison 1983). In the Pacific, leaf rot and corm rot have been the most serious diseases, spreading rapidly through whole plantations, particularly in Melanesia (Ooka 1983). In fact, these diseases were so severe in the early 1970s that some societies in the Solomons ceased taro consumption and switched to the sweet potato. West Samoa has recently lost its entire crop due to these diseases.
Alocasia is interplanted with yams and sweet potatoes in Tonga and Wallis where it is grown in shifting cultivation plots. The planting material is usually the larger suckers (although cormlets may also be used). These are placed in holes 10 to 25 cm deep, preferably between July and September. If planted with spacing of 1.5 m by 1.5 m Alocasia will yield 31 tons/ha, with an average kape root stem weighing 8 to 10 kg and reaching 1.5 m in length.The plant suffers few pests, is weeded when convenient, and is harvested a year after planting (Holo and Taumoefolau 1982: 84).
Swamp Cyrtosperma production has been culturally elaborated in some Pacific societies so that it is surrounded by myth and secrecy (see Luomala 1974 for Kiribati).The planting material may be a sett or a young sucker, and in Kiribati this is placed in a carefully prepared pit that may be several hundred years old, to which mulch has been constantly added. Each new plant is set in a hole with its upper roots at water level, surrounded by chopped leaves of particular plants chosen by the individual planter and topped with black humic sand. It is encased in a basket of woven palm fronds, to which more compost mixture is added as the plant grows. The larger cultivars are spaced at 90 cm by 90 cm; smaller ones are spaced more closely.
A pit is likely to consist of Cyrtosperma plants at various stages of growth. A corm may be harvested after 18 months – or it may be left for 15 years, by which time it is very fibrous and inedible but still brings prestige to the grower’s family when presented at a feast. Yield is uneven due to different cultivation practices but may reach 7.5 to 10 tons/ha. An individual corm may weigh 10 to 12 kg (Vickers and Untaman 1982).
Xanthosoma taro is best grown on deep, well-drained, fertile soils. It tolerates shade and so can be interplanted with other crops such as coconuts, cocoa, coffee, bananas, and rubber, or with subsistence crops such as yams. The planting material is the cormlet or a sett, but the former grows more quickly than the latter. These can be planted at any time of year but grow best if planted just before onset of the rainy season. If they are spaced at l m by l m, the yield is about 20 tons/ha. The plant, which has few pests or diseases, produces a number of cormlets the size of large potatoes. These can be harvested after six months, but they bruise easily, reducing storage time (Weightman and Moros 1982).
Different planting techniques have been developed over time in order to provide a foodstuff that suits both the palate of those eating it and the local growing conditions. Most taro (dryland Colocasia,Alocasia, and Xanthosoma) is grown under dryland conditions with reasonable rainfall, and it seems likely that the aroids were all originally dryland plants (Barrau 1965). Because the techniques involved in the cultivation of wetland Colcasia and swamp Cyrtosperma taro are more arduous than those of dryland cultivation, one suspects that these plants were encouraged to adapt to wetland conditions, probably to meet specific food tastes.
Origins
Colocasia and Alocasia taro are among the oldest of the world’s domesticated food plants. Both apparently have an Asian origin, possibly in India or Burma (Massal and Barrau 1956), but because they consist of vegetal material that has no hard parts, they leave almost no trace in the archaeological record. As a consequence, there has been much room for debate about the early development of the taros.
Some of the debate has centered on the question of whether root crop domestication preceded that of cereals, such as millet and rice, in the Southeast Asia region. Most authorities now agree that root crops came first (e.g., Chang 1977), although C. Gorman (1977) considered rice and taro as sister domesticates. In an overview of the evidence, M. Spriggs (1982) argued that root crops, including taro, were early staples in Southeast Asia, with rice becoming a staple much later.
The time depth is also problematic. It has been suggested that the early agricultural phase of slash-and-burn, dryland cultivation in Southeast Asia took place some 8,000 to 10,000 years ago, with a sequence of dominant cultigens proceeding from root crops to cereals (Hutterer 1983). Dryland taro may have been cultivated for some 7,000 years or more, with wetland (Colocasia) taro forming part of a second stage of development of Southeast Asian food crops (Bellwood 1980).
Prehistorians have given much more attention to wetland taro irrigation techniques and those used in the production of paddy rice than they have to dry-land practices. This is because wetland techniques are said to mark technological innovation and, thus, to be associated with a more complex level of social organization than that required in the production of dryland taro or rice (e.g., Spriggs 1982 for Vanuatu; Kirch 1985 for Hawaii). Yet this does not necessarily mean that foodstuffs produced by irrigation had greater importance in the diet than their dryland counterparts. We need to know the importance of such crops in the food consumption and exchange systems of those people who chose to develop a more complex mode of production. For a food to be considered a staple, the proportion of dietary content is the important aspect, as opposed to the techniques of production or the size of the production units.
Ease of cooking may constitute another reason that taro preceded rice. A hole lined with stones, in which a fire was lit, became an oven with limited tools. The whole taro root could be cooked thoroughly in such an oven, together with fish or pork or other edibles. To cook rice, by contrast, required some form of utensil in which to boil the rice to make it edible, either in the form of cakes, or as a soup.
But if taro, whether Colocasia or Alocasia, had advantages that suggest it was an earlier domesticated foodstuff than rice, its disadvantages lay in its bulk and post-harvest vulnerability. However, advantages outweighed disadvantages, so it is not surprising that these two forms of taro spread as widely as they did across Oceania and into Africa.
Despite its antiquity, however, the origin of Alocasia taro has not attracted as much attention as that of Colocasia taro; similarly, we know more about the origin of Xanthosoma taro than we do about Cyrtosperma taro. This is partly because the Alocasia and Cyrtosperma taros are not as widely used as the other two and partly because, even where they are used as foods (save for Cyrtosperma in Kiribati and Yap), they are not the main foodstuff.
Alocasia taro has its origins either in India (Pluck-nett 1976) or in Sri Lanka (Bradbury and Holloway 1988) but has been grown since prehistory throughout tropical southeast Asia, as well as in China and Japan (Petterson 1977). Cyrtosperma, by contrast, was said to have been first domesticated either in the Indo-Malaya region (Barrau 1965) or in Indonesia or Papua New Guinea, where it has wild relatives (Bellwood 1980). Both Alocasia and Cyrtosperma taros are abundant in the Philippines, where a number of different varieties of each are known (Petterson 1977). Cyrtosperma remains, discovered there by archaeologists, suggest that it was cultivated at least from A.D. 358 (Spriggs 1982), indicating that there was sufficient time to develop a range of plant types yielding less acridic starch foods.
In their reconstruction of the early forms of the Austronesian language, A. Pawley and R. Green (1974) include words for Alocasia, Colocasia, and Cyrtosperma taros, indicating a time depth in the Pacific of some 3,000 to 4,000 years. Thus, all three plants have probably been domesticated and exchanged for over 5,000 years in tropical Southeast Asia.
Xanthosoma taro differs from the other three aroids in having its homeland in tropical America. Little is known about the Xantharoids before the twentieth century, as J. Petterson (1977) points out in her thesis on the dissemination and use of the edible aroids. But she does offer us one possible reconstruction of the spread of what she calls American taro. It was “a most ancient domesticate of the Western hemisphere,” said to have originated in the Caribbean lowlands along the northern coast of South America.
By the time Europeans reached the Americas, Xanthosoma taro had diffused south into northwest South America and north across the Antilles and Central America where several varieties were known. Exactly where Xanthosoma was consumed at this time, and who consumed it, is unclear, although later on taro roots served as an important foodstuff for slaves on sugar plantations.
Geographic Spread
The four aroids have spread around the tropical areas of the world, with Colocasia and Xanthosoma more widely cultivated than Alocasia and Cyrtosperma taros. A range of varieties of each has been developed by human selectivity, and all four are extensively utilized by the island societies of Oceania.
Colocasia taro was carried from its South Asia homeland in both an easterly and a westerly direction, probably some 6,000 years ago (Bellwood 1980). Moving east it became established in Thailand, Malaysia, Indonesia, and the Philippines and from there was carried by canoe into Papua New Guinea, the Marianas, and henceforth into Micronesia and Polynesia (Petterson 1977; Yen 1980; Hutterer 1983; Pollock 1992).The Malay name tales is the base of the common term taro as widely used today. In the four areas of Oceania the Colocasia root has gained a reputation as a highly valued foodstuff that also has prestige value (though not as high as Dioscorea yams). Today it is still cultivated as a food in Hawaii, the Marquesas, Tahiti, the Cooks, the Solomons, and Papua New Guinea. It remains a major foodstuff in Samoa, Tonga, Wallis, Futuna, Fiji, and Vanuatu.
The easterly spread of Colocasia taro across the islands of the Pacific is today associated by prehistorians with the development of Lapita culture some 6,000 years ago. Lapita culture is a construct by prehistorians of a period in the settlement of the Pacific, with the spread of a particular form of pottery as its hallmark. Associated with this culture is the cultivation of Colocasia taro in particular, but Alocasia taro as well.
How sophisticated irrigation technology was introduced by these people moving out of Southeast Asia has not been clearly established. It seems likely that dryland taro could have been introduced to a wider range of environments in the Pacific and, thus, was in existence earlier than irrigated or wetland taro.
For our purposes the important consideration is how these production techniques influenced the acceptability of the crop as a foodstuff. Because people in the Pacific today assert that irrigated taro is softer and less acrid, it is likely that the wetland Colocasia taro has undergone more specific selection than the dryland version, depending on how the root was prepared as a food. For the most part it was cooked whole in the earth oven, to be eaten in slices with accompaniments (as discussed in the next section). But in Hawaii, Rapa, and a few small islands it was employed mainly as poi, a fermented product made from either upland or wetland taro. The dietary uses of Colocasia taro are thus likely to have influenced which plants were selected for replanting and the techniques (whether wet or dry) of production. Moreover, appropriate cooking techniques had to be developed, as well as methods for overcoming the acridity.
In its westward spread, Colocasia taro was planted in India, where it still forms part of the diets of some societies today. It reached Madagascar where it became widely established between the first and eleventh centuries A.D. It was carried further westward in two branches, one along the Mediterranean and the other across Africa south of the Sahara.
The plant attained significance in West Africa where it has been grown ever since. In the Mediterranean region, it was flourishing in Egypt at the time of Alexander’s expedition, where it was known as the Egyptian water lily and Egyptian beans. Virgil and Pliny both referred to the Colocasia plant in their writing, with the latter noting that “when boiled and chewed it breaks up into spidery threads” (quoted in Petterson 1977: 129). Colocasia taro has continued in importance in Egypt and also in Asia Minor and Cyprus until recently when it became too expensive to produce (Petterson 1977).
Colocasia taro reached the Iberian Peninsula probably by about A.D. 714, along with sugar cane. In both West Africa and Portugal the term enyame came to be applied to the Colocasia taro and was picked up by other Europeans as a generic name for all unfamiliar root crops.Thus, to English explorers yams meant any number of root crops, including both yams and Colocasia taro (Petterson 1977).
The latter also reached tropical America from the east, and it became a secondary foodstuff for Peruvian, Ecuadorean, and Amazonian peoples, as well as for those of the Caribbean, where it is known as dasheen or eddoe (Petterson 1977: 185). It seems likely that Colocasia taro was carried by the Iberians in their westward explorations and then brought from Africa to feed slaves during the Middle Passage.
By contrast, Alocasia taro has not traveled so widely. It was carried from Southeast Asia mainly into the islands of Oceania where it has been domesticated on some atolls in Micronesia and Polynesia, as well as on some high islands, such as Samoa, Tonga, Wallis, and Fiji. On those islands where it is grown, a number of different varieties of the plant have been developed locally. In all these places the Alocasia taro makes a significant contribution to the diet.
Its westward spread from Indonesia to India was less prolific (Plucknett 1976). Today, Alocasia plants can be found growing as ornamentals in both tropical and subtropical areas, such as Florida (Petterson 1977) and in the northern part of the north island of New Zealand.They do not, however, serve as food.
Cyrtosperma is a small genus that is used as food almost exclusively in the Oceania region. But Xanthosoma taro spread from its homeland along the northern coast of South America out into the northern part of South America and through tropical Central America. It may have been of some importance as a food in Classic Maya civilization (c.A.D. 200-900).
Spanish and Portuguese contacts with America led to the dispersal of Xantharoids into Europe (they were grown in England as a curiosity in 1710) and, probably, into Africa where they may have died out and then been reintroduced. The root was allegedly brought to Sierra Leone in 1792 by former North American slaves who had fled to Nova Scotia after the American Revolution. However, the generally accepted date for the introduction of Xanthosoma taro to sub-Saharan Africa is April 17, 1843, when missionaries carried the American taro from the West Indies to Accra, Ghana.
It subsequently spread from West Africa to Uganda and through the Cameroons and Gabon to attain varying levels of importance. Beyond Africa, it traveled along Portuguese trading lines to India and the East Indies, following a similar route as the sweet potato. But it has not become an important food crop in Asia, except in the Philippines whence it spread to Malaysia (Petterson 1977).
Xanthosoma was introduced to the Pacific only in the last 200 years, probably via Hawaii (Barrau 1961) and Guam in contact with the Philippines (Pollock 1983). Its spread across the Pacific was aided by missionary activity as much as by island exchange, and the names used in Pacific societies today for Xanthosoma taro suggest the routes of transferal.
Taros as Food
Taro is a very important foodstuff in those societies that use it, both in the household and also for feasts and exchanges. But in terms of world food crops, the taros are considered of marginal importance. They rank behind bananas and root crops, such as cassava, sweet potatoes, and yams, in amounts consumed (Norman, Pearson, and Searle 1984: 221). Nonetheless, taros do have potential in promoting diversification of the world food supply and could make a significant contribution if greater agronomic investment was made. The Root Crops program of the Food and Agriculture Organization of the United Nations (FAO) is attempting to address some of these issues, as is the work of the Australian Centre for International Agricultural Research (ACIAR) (Bradbury and Holloway 1988).
In the Pacific, people have a higher regard for taros than any of the other seven common starchy foods (Pollock 1992). Cassava outranks taros in terms of the tons per hectare produced, but that is because it is a good “safety” crop that will grow in poorer soils and can be harvested as needed when the more preferred starches are in short supply. Yet householders in most Pacific societies would not offer cassava to an honored guest or make it their contribution to a celebration; rather they would go to some lengths to procure Colocasia taro or Dioscorea yams or breadfruit for such purposes. In fact, Colocasia taro, yams, and breadfruit are at the very top of the list for everyday consumption in the Pacific and for exchanges and presentation at feasts. They are also the most expensive of the local foods on sale in the urban markets. The other three taros may be maintained as secondary or fallback foods, but the reputation of a rural family still rests in large part on its ability to produce a good supply of Colocasia taro, together with the other desirable crops, for self-maintenance (Pollock et al. 1989).
The taros (and other starch foods) form the major part of the daily diet of Pacific Island people living on their own land today, much as they have in the past. They are the main substance of daily intake, eaten once a day in the past, but now twice a day. Taros, and the other starches, provide the bulk of the food, the “real” food (kakana dina in Fijian), but are accompanied by a small portion of another foodstuff such as fish, coconut, or shellfish to form what we call a meal in English. If just one of them is eaten without the other, then people are likely to say that they have not eaten, because the two parts are essential to the mental, as well as physical, satisfaction that food confers (Pollock 1985).
Taro maintains this importance in the minds of contemporary Pacific Islanders living in metropolitan areas such as Wellington. The root may be expensive and hard to find, but these people make a great effort to obtain Colocasia taro for special occasions, such as a community feast, or for a sick Samoan or Tongan who may request a piece of taro to feel better.
According to the accounts left by missionaries and other visitors to the Pacific in the nineteenth century, the amounts of taro (particularly Colocasia taro) consumed by Fijians and Tongans, for example, were prodigious. They especially noted the consumption patterns of chiefs, suggesting that all this taro was a cause of their obesity. We have less information, however, regarding the ordinary people’s consumption (see Pollock 1992).
But in Tahiti, and probably elsewhere in the Pacific, food consumption generally varied from day to day and week to week. Europeans were amazed at how Tahitians could cross the very rugged interior of their island, going for four days with only coconut milk to drink, yet when food was available, they consumed very large amounts. Because food habits were irregular, one advantage of taro was that it made the stomach feel full for a long period of time.
Along with notions of routine introduced to the islands by missionaries and administrators came the concept of meals, which usually occur twice daily in rural areas. Taro might be eaten at both the morning and evening meals, and a schoolchild or an adult may carry a couple of slices of taro in a packed lunch. Indeed, schools in Niue are encouraging schoolchildren to bring their lunch in the form of local foods rather than bread and biscuits (Pollock 1983, field notes).Thus, today, an adult may consume a daily total of about 2 kg of Colocasia taro or other starch every day for 365 days of the year.
To a great extent such emphasis on local foodstuffs is the work of local Pacific food and nutrition committees, formed in the early 1980s, that have publicized the benefits of taro and other starches. But in urban areas of the Pacific, taros are scarce, and thus an expensive luxury food. In a Fijian or Samoan marketplace, four Colocasia taros (only enough to feed two adults for one meal) may sell for 5 or 6 dollars, with the other family members having to eat rice or cassava or Xanthosoma taro instead. Those promoting the use of local foods are endeavoring to bring down the price of taros. But to do so requires more agricultural input and other diversifications within the economy.
Colocasia taros are also an essential component of Pacific feasts where they take pride of place, alongside the pigs (used only at feasts), fish, turtle, or (today) beef. Early visitors to the Pacific were amazed at the immense walls of Colocasia taros and yams, topped off with pigs, that formed part of a presentation at a special occasion such as the investiture of a new chief in Fiji or Wallis in the 1860s. These food gifts were contributed by households closely associated with the community hosting the feast and were redistributed to those attending. A great amount of food had to be consumed at these feasts, as there was no means of preserving it (Pollock 1992).
Conversely, there were times when food was very scarce, as after a cyclone or a tidal wave, or during a drought. Such disasters witnessed the Colocasia taro plants damaged and rotted and the Cyrtosperma broken by the wind, so the people had to resort to dry-land taro or Alocasia taro or other starches. In very severe cases (such as the devastating cyclone Val in December 1991 on Western Samoa), households had nothing but fallen coconuts and emergency foods, such as Alocasia taro, to rely on.
Exchanges of both planting material and of harvested taros have constituted a method of adjusting such irregularity in food availability in the Pacific. Before the development of international aid in the 1960s and 1970s, taros and other starches were harvested in Tonga to aid neighbors and relatives in Wallis, Western Samoa, and Fiji. This process of exchange not only enabled families and villages to survive hard times, but it also cemented social relations between whole island nations. In addition, the process of exchange supported the development of a diversified gene pool of the various taros.
Cooking and Processing
All the taros must be cooked very thoroughly because of the oxalic acid crystals in the outer layer of the corm and in the leaves. Thorough cooking reduces the toxicity, and the earth oven allows whole taros to be covered and steamed on hot rocks for two hours or more. In most Pacific societies such an earth oven was made once a day, and in rural areas this is still the case. Boiling on a stove may be quicker, but it is more costly in fuel (Pollock 1992).
Pacific Island people today prefer taro cooked whole and then cut into slices for presentation to the household. Taro must be cooked as quickly as possible after harvesting to retain the best flavor and to avoid decay. Before cooking, each corm or stem of taro is carefully peeled, a process that can produce a skin irritation for those unaccustomed to it, again due to the oxalic acid crystals. The corms or stems are placed either in a coconut leaf basket or on banana leaves around the edge of the earth oven, with the fish (or pig if it is a feast) in the center, and the whole is covered first with leaves, then earth to allow the contents to steam. The oven is opened some two hours later. For special occasions, “puddings” may be made from grated taro mixed with coconut cream and baked in the earth oven.
One of the few societies to develop a processed form of taro was that in Hawaii, where fermented taro was eaten as poi. This was made by steaming, peeling, grinding, and straining the corms to yield a thick paste of 30 percent solids, known as “ready-to-mix” poi, or if more water was added to yield a thinner paste of 18 percent solids, known as “ready-to-eat” poi. Hawaiians refer to the thickness of poi as one-finger, two-finger, or three-finger poi. Either irrigated or dry-land Colocasia taro can be used for making poi, but different varieties of Colocasia taro are not mixed.
The thick paste ferments very rapidly due to lacto-bacilli fermentation, reaching an acidity level of 3.8 by the third day. Hawaiians would wrap the very thick paste, known as ‘ai pa’i, in ti leaves until needed. The addition of a little water to the desired portion was all that was required for serving highly esteemed poi to accompany fish or pork. The very thin paste, by contrast, lasts only three to four days unrefrigerated, and refrigerated poi becomes so rubbery that it is considered inedible (Moy and Nip 1983; Standal 1983; Pol-lock 1992).
Commercialization
Taros are sold whole and unprocessed in the Pacific. In Fiji, where the petioles are left attached to the corm, Colocasia taros are sold by the bundle of three or four tied together. In Tonga and Western Samoa, Colocasia taros are sold by the corm alone, but again in groups of four or more for a given price. The stems of Alocasia taros are sold by the piece, while the cormlets of Xanthosoma taro are sold by the basket, as are sweet potatoes and other root crops.
More of the crop is sold through middlemen in Fiji and Samoa, although producers themselves use family members as agents. Cyrtosperma taro is seldom sold in these larger markets, except in Tarawa, Kiribati, and Kolonia,Yap.
None of these root crops is very durable, so those marketing taro aim for quick sales. Damaged taros will deteriorate rapidly, hence great care is taken in both the harvesting process for market and in removing the tops in Tonga and Samoa to inflict as little damage to the corm as possible.
As early as 1880, Papeete in the Society Islands became a center for the redistribution of local produce (Pollock 1988). From such small waterside markets have grown the large market centers found around the tropical world today (some covering several acres). In each Pacific Island (and Caribbean Island) there is at least one such market in the urban center, and in larger islands, such as Fiji and Papua New Guinea, there are several markets in the various urban centers. These markets have grown in size and diversity over the last 20 years, as urban populations have increased. Only small amounts of taro are sold through supermarkets (Pollock 1988).
Out-migration of populations from the Pacific Islands (and the Caribbean) to metropolitan centers, such as Auckland, Wellington, Sydney, Honolulu, and Los Angeles, has also stimulated the overseas sale of taros, mainly Colocasia. The Tongan, Samoan, and Cook Islands populations are becoming sizable in those centers where demand for taro, mainly for celebratory occasions, has increased. Taro is available in urban markets, such as Otara in Auckland, and in vegetable shops, especially those where Polynesian communities are located. Prices are high, but families will make sacrifices to present some taro when needed to maintain family honor.
Before these outlets provided a steady supply, the various communities made private arrangements to import boxes of taro from their home islands. As a wider supply has become available and the communities have grown, each community has focused its demand on taro from its own island of origin, claiming that it tastes better. Samoans will track down stores that sell Samoan taro, whereas Tongans and Rarotongans go in search of taros from their home islands. Island people themselves are acting more and more as the agents and middlemen, with the whole process promoting the production of taro varieties that will endure sea transport.
Taros are also imported in cooked form to New Zealand by returning residents. In Samoa or Niue, puddings are packed either in a chest freezer or a cardboard box and carried as part of the passenger’s personal luggage. In New Zealand and Australia the families of the passenger then share in this produce “from home.” Such is their social value that several hundred dollars may be spent in overweight luggage in order to transport local foods in this manner.
Another form of commercialization promoted by food and nutrition committees in various Pacific Islands is the use of taro (mainly Colocasia, both corm and leaves) along with other local foods, by hotels, to give tourists a new taste experience. Hawaii has long provided luau feasts for its visitors, which included a small portion of poi and pork, salmon, and coconut pudding. Now Fiji runs competitions in which chefs from leading hotels create recipes that make use of local foods, including taro. This practice, in turn, is leading to increased cooperation with the agriculture authorities to assist producers in regularizing production to supply the hotels.
In Hawaii, where processed taro has been marketed as poi for some 75 years, sales to Hawaiians and to the tourist hotels are supplemented by demand for poi in the mainland United States to help individuals suffering from allergies and digestive problems. As a consequence of this activity, Hawaii is the one place in the Pacific where taro plantations have become heavily commercialized and are run by companies rather than by family units.
Taro chips are now being manufactured in various centers around the Pacific. Local companies are selling their product, promoted by food and nutrition committees, in Fiji and Samoa with reasonable success. In Hawaii, entrepreneurial companies, such as Granny Goose Foods, are marketing taro chips alongside the traditional potato chips, thereby drawing taro into the lucrative snack industry.
In other parts of the tropical world, Colocasia taro may be processed into flour or flakes for commercial purposes. A product Arvi has been developed by the Central Food Technological Research Institute in Mysore, India, that consists of flour made from Colocasia taro. The corms are washed, peeled, and cut into slices, which are kept immersed in water overnight, then washed again and immersed for another three hours. The slices are blanched in boiling water for five minutes, then sun-dried before being ground into flour. A similar process has been used to make taro flour in Nigeria. The flour can be mixed with wheat flour for baking.
A process for making instant taro flakes has been tried in Taiwan and in Nigeria whereby smoke-dried slices are stored away for later eating. Freezing taro has not been very successful, though a local variety was processed for freezing in Shanghai (Moy and Nip 1983).Taro leaves mixed with coconut cream, known in Samoa as palusami, have been canned with reasonable success, but the corm does not can well.
Nutritional Value
The nutritional value of taro has changed over the many years since it was first domesticated. Its users have selected plants that were less toxic, produced larger, less fibrous corms, and better suited their tastes. Such a selection process was facilitated by vegetative propagation, and many different cultivars were developed over time. However, a large proportion of these cultivars have been lost due to lack of interest in root crops by cereal-based colonial powers. Today the FAO and the South Pacific Commission are trying to preserve as many different cultivars in the Pacific as possible so as to increase the diversity of available food crops. Colocasia taro has many more different cultivars than the other three types of taro, indicating its preferred status and its longtime use as a food. The cultivars have different nutritional attributes.
The taro corms of the four different types vary slightly in their composition. All the corms consist mainly of starch and moisture and are high in fiber. They yield between 70 and 133 calories (or 255 and 560 kilojoules) per 100-gram portion, with Alocasia having the lowest range and Xanthosoma taro the highest. The amount of protein varies considerably from 1.12 percent to 2.7 percent depending on the type of taro, its geographical source, and the variety. The corms are also a good source of minerals, particularly calcium, for which Cyrtosperma taro is particularly notable (Standal 1982; Bradbury and Holloway 1988).
Taro leaves consist mainly of moisture and fiber. They are high in protein with a generally higher overall mineral content than the corms. It is only the young leaves of Colocasia taro that are eaten as a rule, although no difference in chemical composition has been found between leaves viewed as edible and those viewed as inedible (Bradbury and Holloway 1988).The use of the leaves as a wrapping in preparations, such as Samoan palusami, adds value to the diet on those special occasions when such a dish is served. Food and nutrition committees are trying to encourage the greater use of leaves, but they are not part of the traditional diet.
The fermented form of taro paste developed long ago by Hawaiians has been found to be a highly digestible product suitable for babies, adults with digestive problems, and those with allergies to cereals. The starch granules are small enough to pass readily into the digestive system. This attribute has led to the commercialization of poi (Standal 1983).
Clearly, taro has considerable merits as a food. It is readily cooked in an earth oven with minimal equipment, or it can be boiled or baked on a stove. It provides a high-bulk foodstuff rich in fiber, with acceptable amounts of vegetable protein and calcium. There is enough variety of cultivars to yield different tasting corms (if taste is an important consideration). But these merits have not been recognized widely enough, an issue the FAO Root Crops Program in the South Pacific is attempting to rectify through agricultural development (Sivan 1984; Jackson and Breen 1985). Simultaneously, food and nutrition committees, through their promotion of local foods, are endeavoring to counter the colonial legacy that bread is best.
Summary
Taro has evolved as a food over several thousand years, as people in tropical areas have selected attributes that suit their needs. Those needs included both consumption and production factors, as well as processing techniques. In the Pacific area, where the taros are most widely used, the people have relied heavily on three forms, Colocasia, Alocasia, and Cyrtosperma, along with the other starches such as yams, breadfruit, and bananas as the main elements in their daily diets, eaten together with a small accompanying dish. Xanthosoma taro has been added to this inventory in the last 200 years, as it will grow in poor soils and can be less acrid.
Vegetation propagation allowed a high degree of selectivity. Factors including the taste of the corm and its size, color, moisture, and acridity have determined over time which setts were replanted and which were discarded.
Most taro has been grown in dryland conditions. The selection of varieties of Colocasia taro that would grow in water is a further development, as is the very specialized technique for raising Cyrtosperma taro on atolls where the salinity of the water is a problem.
Little development has taken place to diversify the edible product. The corms are peeled and cooked in an earth oven by steaming for a couple of hours and are then served in slices. More recently, boiling has been introduced, but it gives a less acceptable flavor.
Ongoing development of the taros was curtailed, to some extent, by colonial Europeans whose preferred food was bread. Taros and other root crops were considered by these newcomers as a mark of the backward nature of these societies, and the colonists introduced crops of a commercial nature, such as cotton, vanilla, sugar cane, and, more recently, coffee and cocoa. These crops were planted on the best land, and taros were relegated to less desirable areas. The result has been not only a loss of many varieties of taro formerly used but also a scarcity of taros for sale in the markets today over and above those needed for household supply.
Only during the last decade of the twentieth century have the root crops, including taro, merited the attention of agricultural specialists. The worldwide pressure for a more differentiated crop base than just the seven basic food crops has led to programs such as the FAO Root Crops Program and ACIAR’s identification of the potential of root crops in the South Pacific. With political independence in the 1960s and 1970s, small nations in the tropics have seen the need to become more self-reliant by reducing their high food import bills. The former importance of the taros has been recognized, and these countries are now taking steps to reestablish them agronomically and economically as a key local crop. The recognition of the importance to health of dietary fiber adds another dimension to taro’s desirability. Exports of taro to migrants in metropolitan areas have stimulated the need for particular farming expertise as well as the development of marketing and processing techniques.
Taro has survived a major hiatus in the nineteenth and twentieth centuries that might have seen it eliminated as a crop or dismissed as one of backward, underdeveloped tropical countries. But cereals, even rice, will not grow readily in many of these tropical areas, whereas the taros are a flexible crop that suits shifting cultivation so that farmers can vary the size of their crops from month to month depending on demand. Nutritionally, taro is very good, especially when complemented with fat from fish or pork. Given agronomic support, taro has great potential for further contributions to the world food supply, and finally, it is a crop that has endured thanks to people’s strong preference for it as their traditional food.