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Crystalline pattern, granular morphology, physicochemical and pasting properties of banana starch and flour from three cooking banana cultivars (Kapas, Kepok and Nangka) and one dessert banana cultivar (Ambon) were compared. The result showed that cooking banana had a B-type crystalline pattern, while the dessert banana exhibited a C-type crystalline pattern. The flour exhibited higher crystallinity than the extracted starch. Nangka and Ambon starches possessed similar crystallinity (33–34%) while the crystallinity of Kapas starch (38.6%) was close to that of Kepok starch (39.4%). Elongated shape was typical of the starch granules of Kapas while spheroidal shape was seen in the rest of the cultivars. Cultivar did not significantly affect the swelling volume (SV) and solubility (except in Ambon cultivar) (p > .05) but determined water absorption capacity (WAC) and freeze-thaw stability (FTS) (p > .05). Ambon cultivar was the most stable to retrogradation while Kepok was the least stable which may be attributed to the different contents of amylose. Pasting properties, color and texture characteristics of starch were dependent on their cultivars and the presence of non-starch components. Non-starch contents increased the functional properties, pasting point and breakdown viscosity but decreased texture characteristics and setback viscosity. Kepok was the most resistant to gelatinization. Overall granule shape and starch crystalline type did not play any role in the different responses to the properties examined in the study but amylose content may have contributed to the freeze-thaw stability while crystallinity may have affected the starch pasting point.

Egg yolk and margarine are commonly applied in starchy food processing as a lipid source. Both may affect the starch properties to different extent. Therefore, the effects of adding egg yolk (0.3, 1.0, and 1.7 g/100 g of flour) and margarine (1, 3, and 5 g/100 g of flour) to banana flour on the complex formation of gelatinized starch-lipid and on paste functional properties were investigated in this study. Native banana flour was used as a control. The complexing index (CI) value increased with the increasing egg yolk or margarine content in the paste. Egg yolk lipids formed complexes with flour starch more favorably than margarine lipids. The heat-moisture treatment (HMT) of banana flour increased its ability to form a complex. Complex formation may partly affect the swelling volume (SV) and freeze-thaw stability (FTS) of pastes. The decrease in SV was smaller in the paste with egg yolk than with margarine. Egg yolk also led to a lesser syneresis and solubility than margarine. For freeze-thaw stability, the interplay roles between the reducing effect of lipid addition and the increasing effect of HMT led to an increased syneresis suggesting that HMT factor prevailed. The reducing effect of lipid addition on egg yolk complex solubility predominated the increasing impact of HMT. Lipid source did not affect pasting properties except set back viscosity. HMT-pretreatment played a major role in the alteration of pasting properties compared to the lipid content. [ABSTRACT FROM AUTHOR]

Crystalline pattern, granular morphology, physicochemical and pasting properties of banana starch and flour from three cooking banana cultivars (Kapas, Kepok and Nangka) and one dessert banana cultivar (Ambon) were compared. The result showed that cooking banana had a B-type crystalline pattern, while the dessert banana exhibited a C-type crystalline pattern. The flour exhibited higher crystallinity than the extracted starch. Nangka and Ambon starches possessed similar crystallinity (33–34%) while the crystallinity of Kapas starch (38.6%) was close to that of Kepok starch (39.4%). Elongated shape was typical of the starch granules of Kapas while spheroidal shape was seen in the rest of the cultivars. Cultivar did not significantly affect the swelling volume (SV) and solubility (except in Ambon cultivar) (p >.05) but determined water absorption capacity (WAC) and freeze-thaw stability (FTS) (p >.05). Ambon cultivar was the most stable to retrogradation while Kepok was the least stable which may be attributed to the different contents of amylose. Pasting properties, color and texture characteristics of starch were dependent on their cultivars and the presence of non-starch components. Non-starch contents increased the functional properties, pasting point and breakdown viscosity but decreased texture characteristics and setback viscosity. Kepok was the most resistant to gelatinization. Overall granule shape and starch crystalline type did not play any role in the different responses to the properties examined in the study but amylose content may have contributed to the freeze-thaw stability while crystallinity may have affected the starch pasting point. [ABSTRACT FROM AUTHOR]