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- For the mining disaster, see Sago Mine disaster.
Sago is a powdery starch made from the processed pith found inside the trunks of the Sago Palm Metroxylon sagu. Metroxylon is the scientific name derived from Greek and means heartwood. The species name is from a local name for the food. Sago forms a major staple food for the lowland peoples of New Guinea and the Moluccas where it is often cooked and eaten as a form of pancake with fish.
Sago looks like tapioca and both are pearly grains of starch, but tapioca is made from the root of the cassava plant. They are similar but are not identical when used in recipes.
Because sago flour made from Metroxylon is the most widely used form, this article discusses sago from Metroxylon unless otherwise specified.
Sago palms grow very quickly, up to 1.5m of vertical stem growth per year, in the fresh water swamps and lowlands in the tropics. The stems are thick and either self supporting or grow with a somewhat climbing habit. The leaves are pinnate, not palmate. They are harvested at the age of 7 to 15 years just before they flower. They only flower and fruit once before they die. When harvested the stems are full of the stored starch which would otherwise be used for flowering and fruiting. The trunks are cut into sections and into halves and the starch is beaten or otherwise extracted from the "heartwood", and in some traditional methods it is collected when it settles out of water. One palm yields 150 to 300kg of starch.
Preparation
Sago (Metroxylon) is made through the following steps:
- Felling the sago palm tree;
- Splitting the trunk open lengthwise;
- Removing the pith;
- Crushing and kneading the pith to release the starch;
- Washing and straining to extract the starch from the fiberous residue;
- Collection of the raw starch suspension in a settling container.
The sago starch is then either baked (resulting in a product analogous to bread or a pancake) or mixed with boiling water to form a kind of paste. Sago can be made into steamed puddings such as sago plum pudding, ground into a powder and used as a thickener for other dishes, or used as a dense glutinous flour.
The starch has also been used to treat fibre to make it more easier to machine. This process is called sizing and helps to bind the fibre, give it a predictable slip for running on metal, standardise the level of hydration of the fibre, and give the textile more body. Most cloth and clothing has been sized and is removed in the first wash.
In Malaysia and Indonesia, sago from Metroxylon is used as a starch in making noodles, white bread, and sago pearls (similar to tapioca). In India pearl sago (a form of sago) is called Sabudana, and is used in a variety of dishes including khichdi, wafers and puddings. The source of this sago is most likely Metroxylon rather than the cycad version, and is sago not tapioca.
Nutrition
Sago flour (Metroxylon) is nearly pure carbohydrate and has very little protein, vitamins, or minerals. However, as sago palms are typically found in areas unsuited for other forms of agriculture, sago cultivation is often the most ecologically appropriate form of land-use, and the nutritional deficiencies of the food can often be compensated for with other readily available foods.
One hundred grams of dry sago yields 355 calories, including an average of 94 grams of carbohydrate, 0.2 grams of protein, 0.5 grams of dietary fiber, 10mg of calcium, 1.2mg of iron, and negligible amounts of fat, carotene, thiamine, and ascorbic acid.
Sago can be stored for weeks or months, although generally it is eaten quickly after it is processed.
Other Uses
In addition to its use as a food source, the leaves and spathe of the sago palm are used for construction materials, for thatching roofs, and the fibre can be made into rope.
Botany
The palm genus Metroxylon has several species. The main source of sago flour is Metroxylon sagu. It is found in Southeast Asia, New Guinea, and some islands in Micronesia and Polynesia. Growing up to 30 meters in height, the sago palm is found in tropical lowland forest and freshwater swamps, and can grow in a wide variety of soils.
Cycad Sago
The Sago Cycad or "Sago Palm" (its common name but a misnomer since it is not an actual palm at all) is a slow-growing wild or ornamental plant.
Processed starch known as sago is made from this and other cycad plants, and is a less frequent food source for some peoples of the Pacific and Indian Oceans. There is a large difference both biologically and dietarily between the two types of sago. Sago as a major dietary food source comes mainly from a palm in the genus Metroxylon. Despite their common name, cycads are not palms (i.e. they are not members of the family Arecaceae but rather from Cycadaceae, a vastly different taxonomic order: cycads are gymnosperms, sometimes called living fossils, while palms are angiosperms).
Sago from the cycad is very different, because unlike Metroxylon, cycad seeds contain highly poisonous compounds. Consumption of cycad seeds has been implicated in the outbreak of Parkinson's Disease-like neurological disorder in various locations in the Pacific such as Guam. Highly toxic cycasin and BMAA compounds are found in most parts of the plant. These must be removed through extended processing before any part can be safely eaten. First, the pith made from the trunk, root, seeds is first ground to a coarse flour, washed carefully to leach out natural toxins, then dried and cooked to become a starchy granular fecula similar to tapioca and is used for many of the same purposes.
SOME INTERESTING FACTS
1. SAGO is known as TAPIOCA GLOBULES in West Bengal, TAPIOCA SAGO or SAGO SEEDS in International market, JAVARISHI in Tamilnadu, SABUDANA or SABU in Maharastra- MadhyaPradesh, Bihar, Rajasthan, Uttar Pradesh & Gujarat.
2. SAGO is popularly used in KHICHADI in Maharastra & MadhyaPradesh, Whereas Used as baby food in West Bengal, KHIR (PAYASAM) in most states and FARIYALI Items in Gujarat, Rajasthan on Vrata-Upavas (Fasting Days). Generally, people regard as a food to be taken during illness for easy digestion & quick recovery.
3. The Industry has developed in India only in last 40 years in and around SALEM (Tamilnadu). By the last 10 to 15 years', very speedy progress is going on in SAMALKOT-KAKINADA belt of East Godavari Dt. in AndhraPradesh.
4. In producing-center states like Tamilnadu, consumption of sago is virtually below 5% of total production. The main reason is lack of popularisation of sago in regular food habits due to some myths that it may be only used in payasam (a dish prepared with Milk, Sugar & Sago).
5. SAGO is full of strength & very easy to digest. Even Doctors are prescribing sago to their patients for fast recovery. That is the reason, why people use it on Vrata-Upavas (fasting) days.
6. SAGO easily mixes with other tastes of spices and other ingredients of the prepared food, so, various dishes can be prepared from it. The only need is for a firm determination to find out new preparations of varieties.
7. SAGO is very low cost food as about 200 GMS. Of sago is enough for a normal person's one-day food, which costs maximum about Rs.4/-to Rs.5/-only in India.
8. The complete production of SAGO in India is done by small-scale industries only. There is not a single organised sector plant in the country for sago production. Thereby, fluctuation of marketing price is abnormal & study is very difficult due to non-availability of complete data of production & sale. Speculative practice is high in this field.
9. Globules shape of INDIAN SAGO is unique in World. In other countries sago is manufactured by dye-pressing system and comes in light cream colour after drier process. In India, it is shaped round by unique swift system & dried under direct sunrays, so, it gets pure white colours & full Round Shape.
10. In India, Sago Consumers like whitish colour & have created a myth that more white sago is more pure and hygienic. Actually, it is not true, as there are various factors to decide about the quality gradation of SAGO. (See Savosa Test Form)
11. SAGO does not attract any insects on storage, if stored in dry condition & will be good for years. It is notable that generally, no pesticides are used at the time of cultivation and harvesting of Tapioca Root, which is the only raw material for Tapioca Sago and Starch.
References
- Flach, M. and F. Rumawas, eds. (1996). Plant Resources of South-East Asia (PROSEA) No. 9: Plants Yielding Non-Seed Carbohydrates. Leiden: Blackhuys.
- Lie, Goan-Hong. (1980). "The Comparative Nutritional Roles of Sago and Cassava in Indonesia." In: Stanton, W.R. and M. Flach, eds., Sago: The Equatorial Swamp as a Natural Resource. The Hague, Boston, London: Martinus Nijhoff.
- McClatchey, W., H.I. Manner, and C.R. Elevitch. (2005). Metroxylon amicarum, M. paulcoxii, M. sagu, M. salomonense, M. vitiense, and M. warburgii (sago palm), ver. 1.1. In: Elevitch, C.R. (ed.) Species Profiles for Pacific Island Agroforestry. Permanent Agriculture Resources (PAR), Holualoa, Hawaii.
- Pickell, D. (2002). Between the Tides: A Fascinating Journey Among the Kamoro of New Guinea. Singapore: Periplus Press.
- Rauwerdink, Jan B. (1986). "An Essay on Metroxylon, the Sago Palm." Principes 30(4): 165-180.
- Stanton, W.R. and M. Flach, eds., Sago: The Equatorial Swamp as a Natural Resource. The Hague, Boston, London: Martinus Nijhoff.
External links
- Species profile for Metroxylon sagu
- Sago Festival
- http://www.knowingfood.com/tapioca/tapiocarecipe.html Asian Sago Dessert Recipes]
- http://www.fao.org/ag/agA/AGAP/FRG/AFRIS/Data/416.HTM
- http://www.botany.hawaii.edu/faculty/McClatchey/Publications/McClatcheyetal2004_Metroxylon.pdf
- http://www.plantapalm.com/vpe/photos/Species/metroxylon_sagu.htm
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