Effect of Sago Starch Addition and Steaming Time on Making Cassava Cracker (Keropok)

Abstract

This work was aimed at investigating the effects of steaming time and different fractions of sago starch (0, 6, 12, 18 and 24%) in mixtures with cassava starch on the properties of crackers as compared to cassava crackers. In the hydrothermal process, the steaming period was varied from 25 to 120 min. The properties of raw starches, half-finished crackers (HFC) and puffed crackers (PC) were determined. Raw cassava starch had lower amylose content, smaller granule size, lower gelatinization and lower swelling power than sago starch. The properties of the raw starch mixtures varied according to the mixing proportions. Both sago starch content and steaming time influenced cracker quality, especially its expansion, which was related to the degree of gelatinization (DG). Increasing sago starch content caused decreased DG of HFC and hence decreased cracker expansion. Two groups of HFC were obtained; low DG (55-65%, 25-45 min steaming time) and high DG (.80%, 60-120 min steaming time) HFC. Generally the expansion increased as the DG increased -however, a too long steaming period (.75 min) again reduced expansion, apparently the thinner starch gel allowed collapse of the air cells. No treatment gave complete gelatinization; which could be due to insufficient water for starch to gelatinize.

Structuring of indirectly expanded snacks based on potato ingredients: A review

“…Very similar observations are reported in many other studies of starch foam packaging materials (Sjöqvist and Gatenholm, 2005;Sjöqvist and Gatenholm, 2007), and the making of keropok snacks (Tongdang et al, 2008). The expansion (porosity) increases with 1-DG, though it levels off at 50%.…”

“…Quite a number of studies on starch based snacks report an optimal moisture content of about MC ¼ 12%, (Lee et al, 2000;Sjöqvist and Gatenholm, 2007;Tongdang et al, 2008). Typical results of the specific volume (the inverse of the mass density) against moisture content are shown in Fig.…”

“…4, displaying the density (inverse with the expansion) and the number density of bubbles as a function of DG. Symbols represent data from (Sjöqvist and Gatenholm, 2005;Case et al, 1992), and the right panel is based on observations from (Tongdang et al, 2008). Lowering the DG will lower the viscoelastic properties, and enhance the expansion.…”

Effect of blending cassava starch, rice, waxy rice and wheat flour on physico-chemical properties of flour mixtures and mechanical and sound emission properties of cassava crackers

“…These slices are solar or hot air dried to semi-finished products which are deep-fried in hot oil with expanded, porous and low density characteristics (Lakleang, 1991). Cassava starch is normally used for these products, because it gives high expansion -however in some cases another starch (corn, wheat, rice or sago starch) is mixed in (Tongdang et al, 2008).…”

Effect of frying parameters on crispiness and sound emission of cassava crackers

“…The cooked dough is then sliced and dried to a half finish product with about 12% moisture content. The half finish product is dipped in hot oil whereby it expands to a porous, low density and crispy product (Tongdang et al, 2008). The frying process is an important process to provide a puffed product.…”