Physicochemical properties of maize starch obtained from intermittent milling and dynamic steeping (IMDS) under various steeping conditions

Physicochemical properties of maize starch obtained under different steeping conditions by intermittent milling and dynamic steeping process (IMDS) were studied. Brazilian dent maize (hybrid XL 606) was milled using a 2x2x3 factorial experimental design with two lactic acid levels (0.0 and 0.55%, v/v), two SO2 levels (0.05 and 0.1%, w/v), and three temperatures (52, 60, and 68degreesC). Properties of starch obtained by conventional wet-milling process (36 hr at 52degreesC, 0.55% lactic acid, and 0.2% SO2) were used for comparison. Starch protein content and solubility increased with presence of lactic acid, while swelling power decreased. Higher SO2 concentration (0.1%) had the same effect as lactic acid on some properties. Steeping temperatures of 60 and 68degreesC increased solubility and most of the thermal properties but reduced swelling power, suggesting stronger starch annealing during IMDS at these temperatures. Some thermal changes on starch granules were visualized by scanning electron microscopy (SEM) at 60 and 68degreesC. Amylose content as well as pasting properties were affected by steeping factors and interactions. Starches from IMDS and conventional wet-milling processes were similar in most properties, indicating that IMDS provides starch with quality similar to that from conventional milling.

Influence of low and high levels of grain defects on maize wet milling

Yields and starch pasting characteristics obtained from wet milling of maize samples with low and high levels of defect grains were compared to those from sound samples. Defect grain groups ere established taking into account the defect degree. Thus the first group consisted of fermented, molded, heated and sprouted grains and the second of insect damaged. hollow, fermented (up to 1/4) grains and those injured by other causes. The grain groups, if present at low levels in the samples, 10% for first group and 17% for second group did not affect the chemical composition of starch and its pasting properties. obtained by the rapid visco analyser. Samples with high levels of grain groups (up to 100%). affected wet milling yields and starch viscosity. Samples with 100% of grains in the first group decreased starch, germ yield and peak viscosity and increased gluten yield. Samples with 100% of grains in the second group decreased germ and fiber yield but increased starch yield. (C) 2002 Elsevier B.V. Ltd. All rights reserved.

Texture and Microstructure of Gelatin/Corn Starch-Based Gummy Confections

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Thermal behaviour of corn starch granules under action of fungal alpha-amylase

Corn starch, partially hydrolyzed by fungal alpha-amylase was investigated by using thermal analysis, microscopy and X-ray diffraction. After enzymatic treatment lower degradation onset temperatures were observed. DSC analysis showed almost similar range of gelatinization temperature, however, the enthalpies of gelatinization increased for the partially hydrolyzed starch granules. According to the X-ray diffraction analysis, stronger cereal pattern peaks were recognized after enzymatic digestion. The results suggested that the hydrolysis was more pronounced in the amorphous part of the starch granules.

New strategies in the preparation of exfoliated thermoplastic starch-montmorillonite nanocomposites

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Morphological, mechanical properties and biodegradability of biocomposite thermoplastic starch and polycaprolactone reinforced with sisal fibers

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Cryopreservation at-80A degrees C of Agaricus blazei on rice grains

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Doses e fontes alternativas de nitrogênio no milho sob plantio direto em solo arenoso

The objective of this work was to evaluate the effect of nitrogen sources and rates on maize nutrition and grain yield under no-tillage system in sandy soil. The experiment was conducted in a Typic Quartzipsamment, in the city of Cassilandia, State of Mato Grosso do Sul, Brazil. A completely randomized block design was used in a factorial array 3x4 with four replicates. Treatments consisted of three sources [urea, extruded urea with starch (Starea), and ammonium sulfonitrate with nitrification inhibitor of 3,4-dimethylpyrazole-phosphate (Entec (R) 26)] and four rates (0, 45, 90 and 180 kg ha(-1)) of nitrogen, applied in side-dressing when the plants presented four and six expanded leaves. The nitrogen source affected N, K, and S concentration in the leaf, but did not interfere in the components of production and maize grain yield. Nitrogen application like ammonium sulfonitrate promoted higher concentrations of N, K and S in the maize leaf in relation to the urea, especially in the larger rates studied. Side-dressing nitrogen fertilization increased the number of ears per plant, number of grains per ear and grain yield, grown under no-tillage system in sandy soil, independent of the used source.

Production and physicochemical properties of resistant starch from hydrolysed wrinkled pea starch

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Levels of replacing corn by cassava starch on performance and carcass characteristics of bulls finished in feedlot

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)