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Evaluation of quality characteristics, antioxidant activity, functional groups of sweet potato by-products and their usage in sandwich bread processing
(2026-04-01)
Dung, Nguyen Chi
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Thuy, Nguyen Minh
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Giau, Tran Ngoc
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Van Hao, Hong
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Van Thanh, Nguyen
A substantial quantity of waste is generated during sweet potato processing, posing environmental and economic challenges. This study aimed to valorize sweet potato by-products (SPB) by drying and milling them into powder and incorporating the material into sandwich bread formulations as a partial replacement for wheat flour at levels of 10–25% (corresponding to formulas B1 to B4) along with control sample B0. The physicochemical, structural, and functional properties of SPB powder were evaluated to determine its suitability as a functional ingredient. The results indicated that SPB powder possesses high nutritional value, with considerable amounts of dietary fiber, bioactive compounds, and strong antioxidant activity. Scanning electron microscopy revealed predominantly oval and polygonal particles with relatively smooth surfaces and intact structures. Fourier-transform infrared spectroscopy confirmed a polysaccharide-rich lignocellulosic composition, including starch, cellulose, hemicellulose, and phenolic compounds. Among the tested formulations, bread containing 15% SPB (B2) was identified as optimal, as it maintained desirable moisture content, loaf volume, and color characteristics while significantly enhancing nutritional quality. Compared with the control, the B2 formulation showed substantial increases in dietary fiber and total polyphenols. These findings highlight the potential of SPB powder as a sustainable, high-fiber functional ingredient for bakery product fortification.
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Effect of different extraction solvents on the yield and enzyme inhibition (α-amylase, α-glucosidase, and lipase) activity of some vegetables
(2023-01-01)
Maser, Wahyu Haryati
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Maiyah, Nur
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Nagarajan, Muralidharan
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Kingwascharapong, Passakorn
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Senphan, Theeraphol
Maser WH, Maiyah N, Nagarajan M, Kingwascharapong P, Senphan T, Ali AMM, Bavisetty SCB. 2023. Effect of different extraction solvents on the yield and enzyme inhibition (α-amylase, α-glucosidase, and lipase) activity of some vegetables. Biodiversitas 24: 3320-3331. The present study investigated the in vitro inhibition of α-amylase, α-glucosidase, and lipase, and antioxidant activities (DPPH, metal chelating, and FRAP) of Allium cepa L., Apium graveolens L., Coriandrum sativum L., and Petroselinum crispum (Mill.) Fuss using solvent 80% ethanol, absolute ethanol, acetone, methanol, n-hexane, chloroform, and hot water. The total phenolic content (TPC) and the FTIR and GC-MS characterization spectra were compared with the activities. The TPC of 80% ethanol extract in A. graveolens L. was the highest among the extracts, with 23.78 mg GAE/g extract. The 80% ethanol extract exhibited the most potent antioxidant activity on DPPH radical scavenging (A. graveolens, 125.57 mg AEAC/g extract), metal chelating (C. sativum, 92.85 mg EECC/g extract), and FRAP activities (C. sativum, 46.98 mg AEAC/g extract). The 80% ethanol extract showed the highest anti-α-amylase (P. crispum, 30.61 mmol ACE/g extract) and anti-α-glucosidase (A. cepa, 595.28 mmol ACE/g extract) activities. In comparison, the absolute ethanol extract of C. sativum showed the highest anti-lipase activity (42.10% inhibition). According to the FTIR spectra, the 80% ethanol extract of the four green leafy vegetables is predicted to have several active compounds. GC-MS identified the compounds responsible for the activity. Studies on the recovery potential of active compounds as oral agents to treat diabetes mellitus with certain solvents are very useful in producing oral agents and functional foods to prevent diabetes mellitus.
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Development of a screening method for adulteration detection in coconut milk via mid-infrared spectroscopy: A study of linear and nonlinear regression method
(2022-12-01)
Sitorus, Agustami
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Bulan, Ramayanty
In the present study, we developed a screening method for detection of adulteration in coconut milk via mid-infrared spectroscopy. Linear and nonlinear regression methods (principal component regression (PCR), partial least squares regression (PLSR), and support vector machine regression (SVMR)) were employed and compared to achieve an optimal screening method. Spectral data were scanned using the FTIR benchtop with a wavelength range of 4000–16702 nm. The calibration models of the linear and nonlinear regression methods were developed using the leave-one-out cross-validation method before testing using predictive data that had been prepared. Furthermore, five spectral data treatment techniques were employed to improve the accuracy of the proposed calibration model. The results obtained show that the SVMR method is better than PCR and PLSR for the detection of adulteration in coconut milk by mid-infrared data spectroscopy. The coefficient of determination for calibration (R2<inf>c</inf>) and prediction (R2<inf>p</inf>), the root mean square error of calibration (RMSEC) and prediction (RMSEP) and the ratio of prediction to deviation (RPD) using the SVMR method were 100%, 0.81, 98.40%, 0.87 and 7.86, respectively. Furthermore, based on RPD analysis, it is known that the SVMR model can be used to perform excellent quality control of water-adulterated coconut milk.
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Change in fatty acid profile, volatile compounds and FTIR spectra of samrong seed oil during storage
(2020-01-01)
Takeungwongtrakul, S.
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Karnjanapratum, S.
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Kaewthong, P.
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Nalinanon, S.
Samrong (Sterculia foetida Linn.) is a wild plant. It is used in traditional medicine. The kernels of samrong seeds have been reported to contain a high amount of oil. The changes in fatty acid profile, volatile compounds, and fourier transform infrared (FTIR) spectra of oil from samrong seed kernel during storage (48 days) were investigated. With increasing storage time, the content of saturated fatty acid (SFA) and polyunsaturated fatty acid (PUFA) decreased. There was little change in fatty acid profile at the end of storage. As to FTIR spectra, a slight change in wave number from 3600 cm-1 to 3200 cm-1 and wave number 1711 cm-1 was observed with increasing storage time. After storage, the results observed 12 volatile lipid oxidation compounds. However, slight changes in abundance of volatile compounds were found. Therefore, samrong seed kernel oil had good oxidative stability.
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Optical absorption and FTIR study of cellulose/tio2hybrid composites
(2019-05-01)
Plermjai, Kittiya
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Boonyarattanakalin, Kanokthip
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Mekprasart, Wanichaya
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Phoohinkong, Weerachon
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Pavasupree, Sorapong
Cellulose/TiO<inf>2</inf> composite was prepared by conventional mixing using distilled water as medium. The structure and relevant properties of cellulose/TiO<inf>2</inf> composite were characterized by X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and UV- Vis spectroscopy. XRD results exhibit typical cellulose structure type I. The absorbance spectra of TiO<inf>2</inf>and cellulose exist in vicinity of 200 nm and 350 nm in the UV range, corresponding to the UV-C, UV-B and UV-A. In addition, the UV absorption band of the composite can be extended covering wide UV region. Corresponding FTIR results suggest the existence of chemical bonding or surface interaction between TiO<inf>2</inf> and cellulose.
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Thermal degradation of flax fibres as potential reinforcement in thermoplastic composites
(2014-03-19)
Chaishome, J.
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Brown, K. A.
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Brooks, R.
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Clifford, M. J.
This work reports on a study of thermal degradation of flax fibres to gain an improved understanding of the use and limitations of flax fibres as reinforcement for thermoplastic composites manufactured by the vacuum forming process. The effect of heating on chemical decomposition and thermal stability was performed, using fourier transform infrared spectrometry (FTIR) and thermogravimetry (TG) techniques. In addition, the characterisation of micro structures of failure surface following tensile testing of the composites was conducted. The results show that the hemicelluloses decomposition of flax fibres during thermal degradation is a factor to have the detrimental effect on the thermal stability of fibres, particularly with low heating rate. The present investigation, A decrease of hemicellulose and pectin content of the fibres, a decrease of consolidation temperature and an increase of heating rate during the manufacturing of flax fibre thermoplastic composites should improve their mechanical performance. © (2014) Trans Tech Publications, Switzerland.
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A rapid synthesis of blue-pigment copper cyclotetraphosphate (cu2P4O12) ricelike grain nanoparticles at low temperature
(2012-12-01)
Chatjuthamanee, Warunthip
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Muanghlua, Rangson
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Boonchom, Banjong
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Vittayakorn, Naratip
A blue-pigment copper cyclotetraphosphate Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> was synthesized by a simple wet preparation method using copper oxide and phosphoric acid at 350 °C. The crystallite size obtained from X-ray line broadening is 53 ± 11 nm for the Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf>. The FTIR spectrum of Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> is assigned a base on the P<inf>4</inf>O<inf>12</inf>4- ion in the structure, which indicates the most striking feature of cyclotetraphospate. XRD and FTIR results of the synthesized CuCu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> indicate the pure monoclinic phase with space group C<inf>2h</inf>6 (C2/c). SEM micrographs of the synthesized Cu<inf>2</inf>P<inf>4</inf>O<inf>12</inf> show rice-like grains, a porous structure and agglomerations, which are important for a specific application. The UV-Vis-NIR spectrum confirms the octahedral coordination of the Cu (II) ion and blue pigment.
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Use of neural network to model the FTIR spectra of PECVD silicon nitride films for cardiovascular pressure sensor applications
(2011-07-20)
Thongvigitmanee, Thongchai
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Titiroongruang, Wisut
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Srihapat, Arckom
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Poyai, Amporn
In this paper, the empirical process models based on neural network are applied to discover the relationship between inputs and outputs of the plasma enhanced chemical deposition (PECVD) silicon nitride process. The design of experiments are based on a 26-2 fractional factorial experiment with four center replicate on six factors which are 1) the SiH<inf>4</inf> flow rate, 2) the NH<inf>3</inf> flow rate, 3) the N<inf>2</inf> flow rate, 4) the chamber pressure, 5) the radio frequency (RF) power/distance between the wafer base and shower gas, and 6) the deposition temperature. Once these experiments are performed, different neural networks are applied to identify these six inputs to the chemical bonding information from the FTIR measurements. The best performances of neural networks for each response are selected based on the smallest prediction error. Then the three-dimensional surface plots are generated to qualitatively interpret factor effects. The corrosion testing in saline solution based on a potentiostatic measurement of an aluminum film with the protective PECVD silicon nitride is demonstrated. This measurement could be used as a tool to identify the best dense PECVD silicon nitride film in order to improve the protective performance of the existing recipe. The silicon nitride film is used as the final passivation layer of the cardiovascular pressure sensor. © 2011 IEEE.
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Grass blade-like microparticle MnPO4·H2O prepared by a simple precipitation at room temperature
(2010-11-01)
Boonchom, Banjong
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Baitahe, Rattanai
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Joungmunkong, Zongporn
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Vittayakorn, Naratip
Grass blade-like microparticle MnPO<inf>4</inf>·H<inf>2</inf>O was synthesized by a simple precipitation at room temperature using a mixture of manganese sulphate monohydrate, phosphoric acid and water at pH=7. The thermogravimetric study indicates that the synthesized compound is stable below 500°C and its final decomposed product is Mn<inf>2</inf>P<inf>2</inf>O<inf>7</inf>. The pure monoclinic phases of the synthesized MnPO<inf>4</inf>·H<inf>2</inf>O and its final decomposed product Mn<inf>2</inf>P<inf>2</inf>O<inf>7</inf> are verified by XRD data. FTIR spectra indicate the presences of the PO<inf>4</inf>3- ion and water molecules in the MnPO<inf>4</inf>·H<inf>2</inf>O structure and the P<inf>2</inf>O<inf>7</inf>4- ion in the Mn<inf>2</inf>P<inf>2</inf>O<inf>7</inf> structure. The thermal stability, crystallite size, and grass blade-like microparticle of MnPO<inf>4</inf>·H<inf>2</inf>O in this work are different from previous reports, which may be caused by the starting reagents and reaction condition for the precipitation. © 2010 Elsevier B.V.

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