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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.

The aims of this study were to evaluate the role of encapsulant materials on the stability of bioactive compounds of red ginger extract powder during storage and determine the composition of the encapsulant materials which produced red ginger extract powder with best stability of bioactive compounds during storage. This study consisted of three compositions of encapsulant materials which are maltodextrin:gum arabic with ratio 10:0, 8:2, and 5:5. The results showed that several compositions of encapsulant materials produced different stability of bioactive compounds of red ginger extract powder. Based on the study result, increasing amount of gum arabic used had better protection to the stability of bioactive compounds of the powders during storage.

In general, native sweet potato starch has inferior characteristics such as it swells easily, does not gel firmly and low paste clarity. The characteristics of native sweet potato starch cause limitation in its utilization. This research aimed to study the effect of physically modified starch on the functional and amylographic properties of native sweet potato starch. The study used a descriptive method with 4 treatments and 2 replications: a) a native sweet potato starch, b) sweet potato modified starch by heat moisture treatment, c) sweet potato starch modified by annealing and d) sweet potato starch modified by pre-gelatinization. The results showed that all three treatments modified starches largely alter the functional and amylographic properties of native sweet potato starch. Heat moisture treated and annealed sweet potato had starches with decreased swelling volume, solubility, peak viscosity, and breakdown viscosity, increased pasting temperature and setback viscosity than its native starch. Pre-gelatinized sweet potato starch has lower bulk density, peak viscosity, breakdown viscosity, setback viscosity and increased swelling volume, solubility and water absorption capacity than its native starch. Key word: functional properties; amylographic properties; sweet potato starch; physically modified

Since the beginning of the 21 th century, demand for natural food additives especially food colorant has increased sharply. The natural one were considered safer, while the synthetic ones are less safe. One source of natural food colorant is anthocyanin pigments from purple sweet potato ( Ipomoea batatas L.). Anthocyanins have good stability at acidic pH especially pH 2-4 so that it can be applied for food products such as beverages with low pH like jelly drink. Nevertheless, anthocyanins are very sensitive to the temperature and light. It is thus important to store food containing anthocyanins in proper condition. The purpose of this study was to determine the proper storage conditions and to predict shelf life of jelly drinks containing encapsulated anthocyanin pigments from purple sweet potato. This research used experimental methods by regression analysis of four treatments and four replications. The treatments were storage of jelly drink in (1) Room temperature with light exposure ( 25 o C±2 o C ) , (2) Room temperature without light exposure (25 o C±2 o C), (3) Refrigerator temperature with light exposure (5 o C±2 o C) and (4 ) Refrigerator temperature without light exposure (5 o C±2 o C). Parameters analysed were: (a) intensity of red color; (b) total anthocyanins; (c) pH value. Observations were made on days 0, 5, 10, 15, 20, 25 and 30. The results showed that the temperature and light affected the decrease in colour intensity, and total anthocyanins of jelly drink. The best treatment was stored at refrigerator temperatures without light exposure, has the smallest decreasing of total anthocyanins (46,03% ) and decreasing of red intensity (3,19 %) during 30 days storage in which the shelf life spanned to around 200 days based on the color intensity. Keyword : anthocyanins pigments; purple sweet potato; regression analysis