Sago from the true sago palm (Metroxylon sagu Rottb.)

The term “sago” is commonly and confusingly used to denote starch of various origins especially tapioca (starch from the root of cassava plant).

Terminologically (Wikipedia, Encarta dictionary), sago is a starch extracted in the spongy centre or pith, of various tropical palm stems, especially Metroxylon sagu. More precisely from the indigenous “sagu” in Indonesia, sago refers to the starch from the TRUE SAGO PALM (Metroxylon sagu or other species of the Genus Metroxylon) as illustrated in the photos below.

PT ANJ Agri Papua (ANJAP) is the pioneering company that systemically develops natural sago palm forests at West Papua into sustainably managed and high-yielding sago forests in an environmentally friendly manner. Basically, only mature sago palms are selectively harvested for processing. Immature follower palms1 are appropriately rehabilitated until maturity through best agronomic management practices with good water management and canal infrastructure, to ensure subsequent harvests at biannual intervals sustainably.

1 Metroxylon sagu is a tillering palm that generates off-shoots or follower palms regularly in a similar manner to that of bananas.

Processing of harvested sago palm trunk

Harvested sago palm trunks are transported to a processing factory for starch extraction.  A 100T/d sago starch mill is now under construction by ANJAP, with more mills of bigger capacities planned in the next few years.  With an estimated starch yield of 6-10T ha-1yr-1, our production from the 40,000 ha mature sago forest will approximately produce 300,000 ton/year of dry sago by 2022.

The sago (サゴ ) from the true sago palm has somewhat different and unique properties as compared with other commercial starches (Table 1).

The unique property of the true sago is especially suited for starch noodle preparation. In Indonesia, nearly all the 100,000 T/yr of sago starch marketed in Java Island is used to produce “glass noodle” or “soo-hun” or  some-times called  sago fen-si  (粉丝 )”. In Malaysia, vast majority of the 50,000T/yr of sago produced in the country are mixed with rice flour in the manufacturing  of flat noodle (kuey-tiau) or vermicelli (bi-hun), to improve the texture and quality of these products.

The special properties of the true sago should be distinguished from that of other ‘sago’ to differentiate its applications in different niche industries.

Table 1: Comparison of the Properties of Sago with other Starches

(Source: Cecil,1982 ; Hamanishi et al., 1999, NTFP/UNIMAS, 2008)

By-products of sago processing

Two common by-products are (a) the hard outer bark removed from the trunk and (b) the starch-rich pith fibre.  They are produced in roughly similar quantity each (on dry matter basis) to that of the dry starch production from the entire palm trunk.The bark can be used as biomass fuel for boilers to generate electricity and heat energy for the sago factory.

The pith fibre (commonly referred as hampas or ampas) is also unique in the sense that it contains about 30-40% of bound starch (dry weight basis). We are currently exploring the possibility of value added products to these fibrous wastes such as bio-fuel briquette, pellets, as well as for bioconversion into fermentation products.

Enquiries for cooperation in joint development of value added products from sago fibrous waste is welcomed.

The page in Mandarin version could be found here.