Characterization and physiological effect of tapioca maltodextrin colloid plasma expander in hemorrhagic shock and resuscitation model

Plasma expanders (PEs) are administered fluids to replace blood volume when massive blood loss has occured. Maltodextrin from tapioca starch was selected as a study candidate to prepare a colloid PE due to an uncomplicated production process. The formulations of mixture between tapioca maltodextrin and 0.9 % sodium chloride solution were prepared and then characterized. This was to investigate the effects of a dextrose equivalent (DE) and the concentration on the physical properties. Storage stability of each formulation was also determined and compared with clinically used PE [6 % hydroxyethyl starch (HES), 130/0.4]. The effects on the circulatory system in hamsters with hemorrhagic shock and resuscitation using prepared PE were also investigated. The results showed that low DE value led to high retrogradation, turbidity and viscosity but low colloid osmotic pressure and poor solubility. Among the prepared solutions, tapioca maltodextrin with DE6 at 10 % w/v concentration had comparable properties with 6 % HES 130/0.4. Animals resuscitated with 10 % DE6 PE had improved mean arterial blood pressure similar to those resuscitated with 6 % HES 130/0.4. However, several parameters in animals resuscitated with 10 % DE6 PE were lower than those resuscitated with 6 % HES 130/0.4, i.e., heart rate, functional capillary density. Therefore, if using tapioca maltodextrin for PE, some properties have to be considered and efficiently optimized.     

The promise of a technology revolution in cassava bioethanol: From Thai practice to the world practice

The abundance of low-cost feedstock and the cost-effective technology are of great importance for reinforcing industrialization of bioethanol for fuel use as sustainably-sourced and eco-friendly energy. This paper describes improved techniques that increase the root productivity of cassava (Manihot esculenta Crantz) and its conversion to bioethanol by the energy-saving technology being developed in Thailand. The productivity of cassava roots can be significantly increased from 22 to 60 tons/ha simply by applying yield improved varieties and good cultivation practices; important ones are soil plowing, high stake quality, weed control, good planting and harvesting period, land conservation with organic fertilizers and water irrigation. Currently, the world production of cassava is around 220 million tons per annum with the average yield of 12 tons/ha and the total acreage of 18.5 million ha. If the root productivity increases, for instance, by 5 tons/ha, around 90 million tons of roots are produced which can be converted to 15,000 ML of ethanol by Simultaneous Saccharification and Fermentation (SSF) process, a current production process of which cooked and enzymatically-liquefied cassava materials are subjected to saccharifying enzymes and yeasts in concert. The promising energy-saving technology for converting cassava chips to ethanol has also been introduced at a pilot scale by using a granular starch hydrolyzing enzyme in an uncooked process.     

Germination Conditions Affect Physicochemical Properties of Germinated Brown Rice Flour

ABSTRACT:  Germinated brown rice has been reported to be nutritious due to increased free gamma-aminobutyric acid (GABA). The physicochemical properties of brown rice (BR) and glutinous brown rice (GNBR) after germination as affected by different steeping times (24, 36, 48, and 72 h depending on the rice variety) and pHs of steeping water (3, 5, 7, and as-is) were determined and compared to those of the nongerminated one (control). As the steeping time increased or pH of steeping water decreased, germinated brown rice flours (GBRF) from both BR and GNBR had greater reducing sugar, free GABA and α-amylase activity; while the total starch and viscosity were lower than their respective controls. GBRFs from both BR and GNBR prepared after 24-h steeping time at pH 3 contained a high content of free GABA at 32.70 and 30.69 mg/100 g flour, respectively. The peak viscosity of GBRF obtained from both BR and GNBR (7.42 to 228.22 and 4.42 to 58.67 RVU, respectively) was significantly lower than that of their controls (255.46 and 190.17 RVU, respectively). The principal component analysis indicated that the important variables for discriminating among GBRFs, explained by the first 2 components at 89.82% of total explained variance, were the pasting profiles, α-amylase activity, and free GABA.     

影响木薯淀粉加工质量因素研究

主要研究了淀粉提取过程中，削皮，水洗，干燥温度对淀粉纯度，白度和糊化粘度的影响。研究结果表明：削皮，水洗和干燥温度影响淀粉白度，纯度和淀粉糊化粘度。在相同水洗次数（1次）和相同干燥温度（50℃）下，未削皮的淀粉样品色发灰，但具有比削皮处理高的峰值粘度，95℃最后粘度，50℃时粘度，峰值降和持久性。在已削皮和相同干燥温度（50℃）下，淀粉水洗次数增加，不但增加淀粉纯度，而且提高淀粉性能，如提高峰值粘度，95℃后粘度，50℃时粘度，持久怀和糊化温度。不同干燥温度对淀粉白度无影响，但纯度随干燥熳度的增加而稍稍增。通常高的干燥温度有高的峰值粘度，95℃最后粘度，峰值降，50℃时粘度和持久性。     

Electrospun polylactic acid and cassava starch fiber by conjugated solvent technique

Smoothed fibers of PLA/cassava starch were prepared by single nozzle electrospinning process intended for tissue scaffold application. PLA in dichloromethane (DCM) solution was immiscible with cassava starch in dimethylsulfoxide (DMSO) solution. A conjugated solvent system was introduced to simply prepare a well-mixed solution of both components. In this experiment, methanol was used as a conjugated solvent between PLA/DCM solution and cassava starch/DMSO solution to create well-mixed solution. Conjugated solvent selection was based on values of polarity index, intermediate between values of DCM and DMSO. Smoothed electrospun fiber of PLA/cassava starch was obtained.     

Effect of Starch Modifications and Hydrocolloids on Freezable Water in Cassava Starch Systems

The effect of starch chemical modifications and hydrocolloids on the proportion of freezable water in starch gels at various moisture contents was studied. The proportion of freezable water increased with moisture content, from less than 6.1% to 84.9% (w/w) of the water fraction between 30% and 70% moisture content (wet weight basis, wwb). A transition between limited and excess water conditions was identified in the range 30‐40% moisture content (wwb), whereby the proportion of freezable water markedly increased from 6.1% to 40.4% (w/w) of the water fraction, in the case of the non‐modified starch control. At 30 and 40% moisture content (wwb), gels made of acetylated starch and hydroxypropylated starch had a significantly lower amount of freezable water than the control, in particular at 40% moisture content (wwb) the amount of freezable water was reduced from 40.4% to 15.3‐25.7% (w/w) of the water fraction. In systems with 50% moisture content (wwb) or higher, modified starches did not show a significant reduction in freezable water compared to the control. Two hydrocolloids, xanthan and carboxymethyl cellulose (CMC) used in a 40% moisture content (wwb) starch system significantly reduced freezable water from 40.4% to 23.9‐24.1% of the water fraction (w/w), at a hydrocolloid: starch ratio of 1:14 (w/w). The linear decrease in the freezable water proportion with xanthan and CMC concentration pointed to the absence of interactions between the starch and hydrocolloid fractions. Therefore, combinations of hydroxypropylated or acetylated starches and xanthan or CMC may be used to control freezable water, particularly in frozen food products with moisture contents around 40% (wwb).     

Physico‐functional and antioxidant properties of purple‐flesh sweet potato flours as affected by extrusion and drum‐drying treatments

Effects of extrusion and drum‐drying treatments on physico‐functional and antioxidant properties of flours prepared from purple‐flesh sweet potato were evaluated. Extrusion variables were feed moisture contents (MC; 10%, 13%, 16%) and screw speeds (SS; 250, 325, 400 r.p.m.), whereas drum‐drying was done at 120, 130 or 140 °C. Effects of MC were generally greater than SS on flour properties. Extruded flours showed higher water absorption and water solubility indices compared with control nonextruded flours. Regardless of SS, total phenolic content and antioxidant activities (DPPH and ABTS) of flours processed at 10% MC were significantly higher than those at 13% and 16%. Both extruded and drum‐dried flours exhibited no peak viscosity, indicating complete gelatinisation of starch. Maximum phenolic content and antioxidant activities of drum‐dried flours were obtained at 140 °C. Although drum‐dried flours had higher antioxidant capacity than extruded flours, both flours could potentially be used as food ingredients.     

Preparation and structural properties of small‐particle cassava starch

Acid and enzyme hydrolyses followed by ball milling were applied to fracture cassava starch granules. Microscopic and chromatographic evidence suggested different mechanisms of the two hydrolyses. Using the enzyme process, granules with a sponge‐like structure and shells with the interior hydrolysed were produced. Amylose and amylopectin were subjected equally to multiple attacks by enzymes, with no significant change in granule crystallinity. The hydrolysed residues could not be effectively broken down by ball milling, although the crystallinity was destroyed. In contrast, the acid treatment caused superficial external corrosion, mainly at the amorphous lamellae, ie the branch points of amylopectin. Acid‐lintnerised starch granules were mostly of Degree of polymerization, DP 10–15 and exhibited increased crystallinity and brittleness, making them more susceptible to breakdown upon milling. Ball milling, although destroying some degree of crystallinity, could effectively reduce the size of acid‐hydrolysed starch, with no further degradation of amylodextrin molecules. By a combination of lintnerisation and ball milling, smaller particle starch (3–8 µm compared with 3–30 µm for native starch) could be produced. It is clear that removal of the amorphous phase prior to milling is critical for effective rupture of the granules. Copyright © 2003 Society of Chemical Industry     

A Study of the Internal Structure in Cassava and Rice Amylopectin

Cassava and rice amylopectins and their ϕ,β‐limit dextrins were debranched and the unit chain compositions were analyzed by gel permeation chromatography and high performance anion‐exchange chromatography. The content of amylose and super‐long amylopectin chains was 15.5‐15.6% and 0.8‐1.2% in cassava and 15.1‐18.7% and 3.4‐8.6% in rice starches, respectively. The internal unit chain profiles of the amylopectin samples were obtained from the ϕ,β‐limit dextrins. Short B‐chains were subdivided into a major group (BS_major) with a degree of polymerization (DP) of 8‐25 and a minor group of “fingerprint” B‐chains (B_fp) with DP 3‐7. Cassava and rice amylopectins possessed different amounts and patterns of B_fp‐chains. The rice samples contained higher amounts of B_fp‐chains, which suggested larger size of its clusters when compared with cassava. The content of the shortest “fingerprint” A‐chains (A_fp) was also variable, especially between the rice cultivars. The position of the internal chains in the original amylopectin chain profile was traced. The reconstructed B‐chain profiles fitted well with the original profiles. This implied that most of the B‐chains carried external chain segments of similar lengths, which corresponded to the experimentally measured average length.