scholarly journals Synthesis, physicochemical characterization, and functional properties of an esterified starch from an underutilized source in Nigeria

2012 ◽  
Vol 12 (55) ◽  
pp. 7001-7018
Author(s):  
M Emeje ◽  
◽  
R Kalita ◽  
C Isimi ◽  
A Buragohain ◽  
...  
Keyword(s):  
West Africa ◽  
Sustainable Use ◽  
Physicochemical Characterization ◽  
Exothermic Peak ◽  
Absorption Capacity ◽  
Scanning Calorimetry ◽  
Native Starch ◽  
Petit Mil ◽  
Modified Starches ◽  
Granule Morphology

Acha (Digitaria exilis Sta pf), also known as Findi, Hungry rice , Petit mil and White fonio, is a small seeded cereal, indigenous to West Africa, which is generally classified as millet. It grows in various parts of Nigeria, Sierra Leone, Ghana, Guinea Bissau and Benin Republic . That species is the most important of a diverse group of wild and domesticated Digitaria species that are harvested in the savannas of West Africa. It is one of the primary cereals of southern Sudan and Ethiopia in Africa. It has potential to improve human nutrition, boost food security, foster rural development and support sustainable use of lands . In this study, acha starch was subjected to modification by acetylation. The acetylated acha starch with degree of modification 0.78 had reduced foaming capacity and amylose contents. The starches have similar organoleptic properties ranging from white, gritty, non sticky to bland tastes. P hysicochemical indices investigated such as true density, bulk and tapped densities, water absorption capacity, moisture content, total and acid insoluble ash, and pH were reduced by the acetylation of acha starch. The modification resulted in a significant (P < 0.05) increase in the solubility as well as water and oil absorption capacities of the starch. Scanning electron micros copy revealed starch granules that were predominantly polygonal in shape. Acetylation did not alter the granule morphology. X -ray pattern of the native starch was A type, with similar pattern in the acetylated derivative. Fourier transform infrared spectroscopy (FTIR) results revealed a new band at 1728 cm -1. Thermogravimetry revealed 3 phase decomposition of both the native and modified starches. The a cetylation as revealed by Differential scanning calorimetry studies improved the gelation capacity of the native starch and revealed two endothermic peaks and one exothermic peak each for both starches . There was considerable reduction in the peak temperature of gelatinization (Tp) of native starch and a significant (P < 0.05) decrease in the enthalpy of gelatinization (DH) was noticed after acetylation.

scholarly journals Use of hydrolysis prior to the chemical and thermomechanical modification of rice starch: alternative to traditional modification treatments

Biotecnia ◽  
2021 ◽  
Vol 23 (1) ◽  
pp. 151-160
Author(s):  
Nancy Grajeda ◽  
Mayra Márquez ◽  
Tomás Galicia García ◽  
Iván Estrada ◽  
Mónica Mendoza ◽  
...  
Keyword(s):  
Crystallinity Index ◽  
Wall Material ◽  
Rice Starch ◽  
Scanning Calorimetry ◽  
Food Ingredient ◽  
Relative Crystallinity ◽  
Native Starch ◽  
Modified Starches ◽  
Acetyl Group ◽  
Starch Gels

Rice starch isolated (NS), was subjected to chemical and thermomechanical modification with previous hydrolysis (MHS) and without previous hydrolysis (MS) to be evaluated on main starch properties as degree of substitution (DS), color, water absorption and solubility index (WAI, WSI), viscosity, texture, thermal properties (differential scanning calorimetry DSC) and structural properties (infrared-IR, Xray-Rx analysis, and relative crystallinity index-ICR). The modified starches were compared to native starch (NS). The DS obtained in both starches was within the range allowed by the FDA for its safety use as food ingredient (0.01-0.2). The modification showed an increase in WAI and WSI values, being WAI value higher in MS (4.80) and WSI value higher in MHS (32.06). The viscosity of retrogradation showed a significant decrease (P<0.05) in both starches (HMS 0.013 and MS 5.613), obtaining gels with greater stability, however, the hardness of starch gels decreased (60 %) while the adhesiveness decreased only in MS (66 %). The crystallinity index (ICR) of the modified starches increased with regard to the native starch indicating a depolymerization of the molecule due to the modification. The presence of the acetyl group in the starch molecule was observed in the signals between 1650 to 1744 cm-1 confirming the esterification. The starches showed a high potential for its application as edible coatings and as wall material for microencapsulation.

scholarly journals Effect of the acetylation process on native starches of yam (Dioscorea spp.)

2016 ◽  
Vol 69 (2) ◽  
pp. 7997-8006 ◽  
Author(s):  
Jairo Salcedo Mendoza ◽  
Jorge Hernández RuyDiaz ◽  
Alfredo Fernández Quintero
Keyword(s):  
Structural Changes ◽  
Raw Materials ◽  
Amylose Content ◽  
Reaction Times ◽  
Absorption Capacity ◽  
Degree Of Crystallinity ◽  
X Ray Diffraction ◽  
Modified Starches ◽  
Granule Morphology ◽  
Low Degrees

In Colombia, it is necessary to produce native and modified starches for the use of amylaceous raw materials of major socioeconomic importance. In this study, the effects of the acetylation process on structural, morphological and functional properties of native starches yam, Dioscorea spp. (D. alata and D. rotundata) were evaluated. Chemical modification by esterification with acetic anhydride was performed at different reaction times, and morphological and structural changes were assessed using the following techniques: infrared spectroscopy (FTIR), X-ray diffraction and scanning electron microscopy (SEM). Acetylation produced slight changes in the granule morphology, and a decreased degree of crystallinity (DC) associated with a slight increase in the amylose content was observed. The introduction of acetyl groups into the starch structure caused a decrease in the gelatinization temperature and an increased retro gradation tendency. The acetylated starches had low degrees of substitution (DS<0.2), meaning they can be used in the food industry, considering that they showed greater stability, greater water absorption capacity and better solubility than native starches.

scholarly journals Functional and Amylographic Properties of Physically-Modified Sweet Potato Starch

2017 ◽  
Vol 2 (6) ◽  
pp. 689 ◽  
Author(s):  
Herlina Marta ◽  
Tensiska Tensiska
Keyword(s):  
Sweet Potato ◽  
Potato Starch ◽  
Absorption Capacity ◽  
Modified Starch ◽  
Density Peak ◽  
Native Starch ◽  
Modified Starches ◽  
Sweet Potato Starch ◽  
Lower Bulk Density ◽  
Swelling Volume

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

Enhancement of Solubility and Dissolution Rate of Poorly Water Soluble Drug using Cosolvency and Solid Dispersion Techniques

1970 ◽  
Vol 1 (4) ◽  
pp. 349-356
Author(s):  
Meka Lingam ◽  
Vobalaboina Venkateswarlu
Keyword(s):  
Dissolution Rate ◽  
Solid Dispersions ◽  
Physicochemical Characterization ◽  
Aqueous Solubility ◽  
Water Soluble ◽  
Scanning Calorimetry ◽  
Peg 400 ◽  
Water Soluble Drug ◽  
Poorly Water Soluble ◽  
Poorly Water Soluble Drug

The low aqueous solubility of celecoxib (CB) and thus its low bioavailability is a problem.    Thus, it is suggested to improve the solubility using cosolvency and solid dispersions techniques. Pure CB has solubility of 6.26±0.23µg/ml in water but increased solubility of CB was observed with increasing concentration of cosolvents like PEG 400, ethanol and propylene glycol. Highest solubility (791.06±15.57mg/ml) was observed with cosolvency technique containing the mixture of composition 10:80:10%v/v of water: PEG 400: ethanol. SDs with different polymers like PVP, PEG were prepared and subjected to physicochemical characterization using Fourier-transform infrared (FTIR) spectroscopy, X-ray diffractometry (XRD), differential scanning calorimetry (DSC), solubility and dissolution studies. These studies reveals that CB exists mainly in amorphous form in prepared solid dispersions of PVP, PEG4000 and PEG6000 further it can also be confirmed by solubility and dissolution rate studies. Solid dispersions of PV5 and PV9 have shown highest saturation solubility and dissolution rate

scholarly journals On the Effectiveness of Oxygen Plasma and Alkali Surface Treatments to Modify the Properties of Polylactic Acid Scaffolds

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1643
Author(s):  
Ricardo Donate ◽  
María Elena Alemán-Domínguez ◽  
Mario Monzón
Keyword(s):  
Surface Properties ◽  
Enzymatic Degradation ◽  
Oxygen Plasma ◽  
Physicochemical Characterization ◽  
Surface Treatments ◽  
Carboxyl Groups ◽  
Scanning Calorimetry ◽  
Water Contact ◽  
Angle Measurements ◽  
3D Printed

Surface modification of 3D-printed PLA structures is a major issue in terms of increasing the biofunctionality and expanding the tissue engineering applications of these parts. In this paper, different exposure times were used for low-pressure oxygen plasma applied to PLA 3D-printed scaffolds. Alkali surface treatments were also evaluated, aiming to compare the modifications introduced on the surface properties by each strategy. Surface-treated samples were characterized through the quantification of carboxyl groups, energy-dispersive X-ray spectroscopy, water contact angle measurements, and differential scanning calorimetry analysis. The change in the surface properties was studied over a two-week period. In addition, an enzymatic degradation analysis was carried out to evaluate the effect of the surface treatments on the degradation profile of the 3D structures. The physicochemical characterization results suggest different mechanism pathways for each type of treatment. Alkali-treated scaffolds showed a higher concentration of carboxyl groups on their surface, which enhanced the enzymatic degradation rate, but were also proven to be more aggressive towards 3D-printed structures. In contrast, the application of the plasma treatments led to an increased hydrophilicity of the PLA surface without affecting the bulk properties. However, the changes on the properties were less steady over time.

Identification of Amber and the Copal under Heat Pressurized Process

2012 ◽  
Vol 554-556 ◽  
pp. 2112-2115
Author(s):  
Hui Li ◽  
Xuan Wang ◽  
Yong Zhu ◽  
Qin Ren
Keyword(s):  
Chemical Properties ◽  
Peak Position ◽  
Exothermic Peak ◽  
Endothermic Peak ◽  
Scanning Calorimetry ◽  
Natural Resin ◽  
Before And After ◽  
Artificial Heat ◽  
Physical And Chemical ◽  
And Chemical Properties

Amber and copal belong to the natural resin, which are similar and transitional in the physical and chemical properties. The artificial heat-pressurized treatment is contributed to the polymerization of the natural copal, and turns into green, yellow-green and deep orange-yellow copal. It is very difficult to identify amber from the heat- pressurized treatment copal only based on the gemological parameters.The thermal behavior of amber and the copal before and after heat-pressurized treatment were analyzed by means of differential scanning calorimetry (DSC), Fourier transform infrared spectroscopy(FTIR) and nuclear magnetic resonance(NMR). The results show that amber exists an evident endothermic peak around 123~132°C, and copal reveals an obvious endothermic peak at about 174~178°C, and the heat pressurized treatment copal occurs a clear exothermic peak around 150~152°C. The differences between endothermic or exothermic transition and peak position reveal occurring thermal oxidation or the bond breaking or the melting, which are of great significance in the identification.

scholarly journals Study of the Performance of Particles Based on Modified Starches Containing Potassium Sorbate and Incorporated into Biodegradable Films: Physicochemical Characterization and Antimicrobial Action

Chemistry ◽  
2021 ◽  
Vol 3 (2) ◽  
pp. 658-671
Author(s):  
Paola Alzate ◽  
Lía Gerschenson ◽  
Silvia Flores
Keyword(s):  
Control Systems ◽  
Physicochemical Characterization ◽  
Potassium Sorbate ◽  
Biodegradable Films ◽  
Ultrasound Technique ◽  
Yellowness Index ◽  
Solubility In Water ◽  
Zygosaccharomyces Bailii ◽  
Modified Starches ◽  
Antimicrobial Performance

Ultrasound technique was used to produce native and acetylated cassava starch particles containing potassium sorbate (KS). In order to obtain an active packaging, films with addition of native starch particles containing KS (NKSPF) or added with acetylated starch particles containing KS (AKSPF) were formulated. As control systems, films without KS (CF) or added with KS that was not retained in particles (KSF), were produced. The NKSPF and AKSPF microstructure was consistent with composite materials. Tensile test revealed that CF and KSF were ductile and extensible (stress at break (σb) 2.8–2.5 MPa and strain at break (εb) 284–206%), while NKSPF and AKSPF were more resistant films with higher Young’s Modulus (148–477 MPa) and σb (3.6–17 MPa) but lower εb (40–11%). Moreover, NKSPF and AKSPF developed lower Yellowness Index (6.6–6.5) but higher opacity (19–23%) and solubility in water (31–35%) than KSF (9, 10.8% and 9%, respectively). It was observed that KSF and NKSPF moderately reduced the Zygosaccharomyces bailii growth while AKSPF showed the highest yeast inhibition, three Log-cycles, compared to CF. Additionally, FTIR spectroscopy revealed intensified interactions between KS and modified starch. It was concluded that starch sonication and acetylation were useful modifications to produce particles carrier of KS that improved the physical and antimicrobial performance of active films.

METHOD OF PROCESSING COLLAGEN FRESHWATER FISH TO OBTAIN A MATERIAL WITH A HIGH MOISTURE ABSORBING ABILITY

2019 ◽  
Author(s):  
Л.В. АНТИПОВА ◽  
С.А. ТИТОВ ◽  
И.В. СУХОВ
Keyword(s):  
Freshwater Fish ◽  
Moisture Absorption ◽  
Raw Materials ◽  
Silver Carp ◽  
Absorption Capacity ◽  
Personal Hygiene ◽  
Test Material ◽  
Free Access ◽  
High Moisture ◽  
Scanning Calorimetry

Исследовано взаимодействие коллагена пресноводных рыб с водой для повышения его водопоглощающей способности. Объектом исследования был вторичный продукт переработки рыбного сырья – шкуры прудовых рыб, преимущественно толстолобика. Для исследования были использованы методы термогравиметрии и дифференциальной сканирующей калориметрии. Измерения проведены на приборе синхронного термического анализа модели STA 449 F3 Jupiter. Установлено, что основная доля влаги связывается адсорбционным или осмотическим путем, а на долю капиллярной влаги приходится всего 7% массы воды, связанной образцами. Большая величина энергии связи адсорбции – 4 Дж/моль свидетельствует о способности функциональных групп коллагена к созданию гидратной оболочки, содержащей значительное количество воды. Для увеличения влагопоглощающей способности необходимо разрыхление коллагеновых волокон, что увеличивается свободный доступ влаги к фибриллам белка, увеличивающим впитывание влаги. Для эффективного разрыхления предложено выдерживать шкуры толстолобика в растворе органических кислот концентрацией 0,5%. Это позволяет добиться высокой влагоемкости, которая достигает 35–40 объемов влаги на 1 единицу массы исследуемого материала, что делает перспективным использование коллагена в качестве материала для впитывающих влагу слоев средств личной гигиены, одежды, обуви. The interaction of freshwater fish collagen with water to increase its water absorption capacity was studied. The secondary product of processing of fish raw materials – skins of pond fish, mainly silver carp, was the object of study. Methods of thermogravimetry and differential scanning calorimetry were used for the study. Measurements were carried out on the device of synchronous thermal analysis of model STA 449 F3 Jupiter. It was found that the bulk of the moisture is bound by adsorption or osmotic way, and 7% of mass of the water connected by samples fall to the share of capillary moisture. A large amount of adsorption binding energy – 4 J/mol indicates the ability of collagen functional groups to create a hydrated shell containing a significant amount of water. Loosening of collagen fibers is necessary to increase the moisture absorption capacity, which will increase the free access of moisture to the protein fibrils, increasing the absorption of moisture. It is proposed to withstand the skins of silver carp in a solution of organic acids with a concentration of 0,5% for effective loosening. This makes it possible to achieve high moisture capacity, which reaches 35–40 volumes of moisture per 1 unit mass of the test material, which makes it promising to use collagen as a material for moisture-absorbing layers of personal hygiene products, clothing, and shoes.

scholarly journals THE PHYSICOCHEMICAL CHARACTERISTICS OF RECYCLED-PLASTIC PELLETS OBTAINED FROM DISPOSABLE FACE MASK WASTES

2021 ◽  
Vol 23 (1) ◽  
pp. 16
Author(s):  
Vienna Saraswaty ◽  
Rossy Choerun Nissa ◽  
Bonita Firdiana ◽  
Akbar Hanif Dawam Abdullah
Keyword(s):  
Tensile Strength ◽  
Physicochemical Characterization ◽  
Face Mask ◽  
Physicochemical Characteristics ◽  
Scanning Calorimetry ◽  
Elongation At Break ◽  
Ft Ir ◽  
The Government ◽  
Plastic Pellets

THE PHYSICOCHEMICAL CHARACTERISTICS OF RECYCLED-PLASTIC PELLETS OBTAINED FROM DISPOSABLE FACE MASK WASTES. The government policy to wear a face mask during the COVID-19 pandemic has increased disposable face mask wastes. Thus, to reduce such wastes, it is necessary to evaluate the physicochemical characteristics of disposable face masks wastes before the recycling process and the recycled products. In this study, physicochemical characterization of the 3-ply disposable face masks and the recycled plastic pellets after disinfection using 0.5% v/v sodium hypochlorite were evaluated. A set of parameters including the characterization of surface morphology by a scanning electron microscope (SEM), functional groups properties by a fourier transform infra-red spectroscopy (FT-IR), thermal behavior by a differential scanning calorimetry (DSC), tensile strength and elongation at break were evaluated. The surface morphological of each layer 3-ply disposable face mask showed that the layers were composed of non-woven fibers. The FT-IR evaluation revealed that 3-ply disposable face mask was made from a polypropylene. At the same time, the DSC analysis found that the polypropylene was in the form of homopolymer. The SEM analysis showed that the recycled plastic pellets showed a rough and uneven surface. The FT-IR, tensile strength and elongation at break of the recycled plastic pellets showed similarity with a virgin PP type CP442XP and a recycled PP from secondary recycling PP (COPLAST COMPANY). In summary, recycling 3-ply disposable face mask wastes to become plastic pellets is recommended for handling disposable face mask wastes problem.

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