The objective of this study was to investigate the effects of annealing, succinylation, and a dual modification process (succinylation–annealing) on the physicochemical, thermal, and morphological properties of corn starch. Specifically, the properties of interest were the water-binding capacity (WBC), swelling power, paste clarity, solubility, pasting properties, stability ratio, and thermal and morphological characteristics. The dual modification process increased the physicochemical properties (WBC, swelling power, peak viscosity, and paste clarity) and increased the gelatinization temperature and gelatinization enthalpy (∆H), but had no effect on the morphological properties and X-ray diffraction patterns. A comparison of samples, made using each of the processes, showed that dual modification increased the stability ratio (more stable viscosity under thermal and shear stress), which was 0.69 for dual modified starch, compared with 0.64, 0.58 and 0.44 for native, succinylated, and annealed starches, respectively. The findings of the present study are of potential use in the food industry.

The purpose of this research was to investigate the effects of temperature variation (80, 90, 100 and 110 o C) in the pre-gelatinization methods on physical (whiteness), chemical (moisture content) and physicochemical properties (water absorbtion capacity, solubility, and swelling power) of yam bean modified flour. This research used Completely Randomized Design (CRD) with variation of temperature variable. It was performed with three replicates of samples. The results showed that the higher temperature lead to decrease whiteness degree but increased moisture content, water absorbtion and sollubility. However, more higher temperature has no significance difference in swelling power value. The results are very important to develop food product, which are require high solubility value in water.

Jack bean is a local legume that can grow in suboptimal land and potential to be developed in Indonesia. Jack bean seed has 33.32% of protein and 61.15% of carbohydrate so it can become a starch source for the food industry. Native starch has a limited application on food products because of its weak characteristics such as being unstable to heat and shear. Heat Moisture Treatment (HMT) starch modification is needed to overcome the weaknesses. HMT is a natural modification because it does not leave a chemical residue. The objective of this research was to investigate the effects of heat moisture treatment (HMT) with various moisture content and time on the pasting properties (peak, through, breakdown, final, setback viscosity, peak time, and peak temperature) of jack bean modified starch. This research used Factorial Completely Randomized Design (FCRD) with two factors, varying moisture content (27%, 30%, 33%) and time (10 h, 13 h, 16 h). The results show that the various moisture leads to increase peak-time, pasting temperature and decrease peak viscosity, through viscosity, breakdown, final and setback viscosity. In addition, higher HMT time could increase peak time, pasting temperature but decrease peak, trough, breakdown, final and setback viscosity.

ABSTRAK Jewawut (Foxtail Millet) merupakan sumber karbohidrat, mempunyai aktivitas antioksidan, kaya kandungan vitamin dan mineral, serta memiliki kandungan serat pangan yang tinggi. Pengolahan jewawut dalam bentuk tepung lebih memudahkan dalam aplikasi serta memiliki daya simpan yang lebih lama. Proses perendaman dalam pembuatan tepung dilaporkan dapat memperbaiki karakteristik tepung jewawut. Tujuan dari penelitian ini adalah untuk mempelajari pengaruh lama perendaman terhadap karakteristik fisik, kimia dan organoleptik tepung jewawut. Penelitian ini menggunakan Rancangan Acak Lengkap dengan 6 perlakuan (perendaman 0 jam, 1 jam, 2 jam, 3 jam, 4 jam dan 5 jam) dan diulang 4 kali. Hasil penelitian menunjukkan bahwa semakin lama perendaman menurunkan kadar air, kadar abu, pH, dan densitas kamba sedangkan rendemen dan kadar asam lemak bebas meningkat. Perendaman menyebabkan berkurangnya kekerasan biji sehingga rendemen meningkat,tekstur tepung yang dihasilkan lebih halus serta kadar air menurun. Tepung dengan lama perendaman 4 jam menghasilkan karakteristik fisik, kimia dan organoleptik yang terbaik dengan nilai rendemen 99,94%; densitas kamba 0,61 g/ml; pH 6,65; kadar air 6,23%; kadar abu 1,46% dan ALB 1,152%. Hasil analisis awal menunjukkan tepung jewawut memiliki kadar serat pangan yang tinggi yaitu 8,21% dan kandungan amilosa yang rendah 6,96%-9,29 (sehingga bersifat lengket, dan tingkat pengembangan rendah). Tepung jewawut dengan karakteristik fisikokimia yang terbaik diharapkan dapat diaplikasikan dalam berbagai produk olahan, sehingga dapat mengurangi konsumsi terigu. Kata kunci: jewawut, lama perendaman, karakteristik tepung jewawut, serat pangan, fungsional ABSTRACT Anna Sulistyaningrum, Rahmawati, dan Muhammad Aqil. 2017. Effect of soaking duration on the characterization of millet flour. Foxtail Millet is a source of carbohydrates, have antioxidant activity, rich in vitamins and minerals, and has a high fiber content of food. Millet processing in the form of flour further facilitate the application and has a longer shelf life. Soaking process in the manufacture of flour is reported to improve the characteristics of millet flour. The purpose of this study was to determined the effect of soaking on the characteristics of the physical, chemical and organoleptic millet flour. This study used a completely randomized design with 6 treatments (soaking with 0, 1, 2, 3, 4, and 5 hours) and repeated 4 times. The results showed that the longer of soaking will reduce water content, ash content, pH, and density, in other to rendement and free fatty acid will increase. Soaking results in reduced hardness of the seeds so that rendement is increased, the texture of the resulting flour is smoother and the water content decreases. Flour with soaking time of 4 hours to produce phisic, chemical and organoleptic characteristics of the best with rendement 99,94%; kamba density 0,61 g/ml; pH 6,65; water content 6,23%; ash content 1,46% and FFA 1,152%. The Initial analysis showed that millet flour has a high dietary fiber cont...