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1.
Sha Liu JianHui Xiao YaPing Feng MianLing Zhang Ying Li Jin Tu LiYa Niu 《International Journal of Food Science & Technology》2022,57(3):1791-1803
Konjac glucomannan/sodium alginate composite edible boba (KGM/SA-boba) with good taste is very popular in China, and it is an outstanding carrier for health potential ingredients. In this work, KGM/SA-boba were fortified with 0.25, 0.50, 0.75 and 1.00% purple sweet potato anthocyanin (PSPA), then characterised by the water distribution, texture, microstructure, in vitro release property of PSPA and antioxidant capacity. LF-NMR analysis demonstrated that the free water of KGM/SA-boba could transfer to tightly bound water with the addition of PSPA that made it with better water-binding ability, higher springiness and lower hardness. And the results of SEM and rheology showed that PSPA could stabilise the microstructure of KGM/SA-boba by forming more amorphous regions and hydrogen bonds proved by the results of DSC and FT-IR. Furthermore, 50% of PSPA in PSPA-fortified KGM/SA-boba can be released at the first hour in a simulated gastrointestinal environment. And the scavenging capacity of DPPH and ABTS of the PSPA-fortified KGM/SA-boba after digestion was higher than that of PSPA alone. Generally, PSPA could improve the texture while KGM/SA-boba in turn would make PSPA more stable in the gastrointestinal digestive system. 相似文献
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Xue Ren Tiantian Tang Xinfang Xie Wenjun Wang Xuanming Tang Charles S. Brennan Jie Zhang Zhidong Wang 《International Journal of Food Science & Technology》2020,55(11):3475-3483
The effect of a traditional dish sour and spicy potato silk preparation and cooking process on B vitamins, phenolic profiles and antioxidant activities was investigated. Results showed that cutting of potato caused an increase in VB1, VB2, nicotinic acid, nicotinamide, VB7 and VB9. Soaking decreased the content of B vitamins and vitamin C. Blanching and rinsing caused the contents of B vitamins and vitamin C decrease compared to the control. The content of VB1, VB5 and VB6 after rinsing increased compared to soaking and blanching processes. However, VB1, nicotinamide, VB5, VB6 and VC decreased sharply after the stir-frying process. The content of VB1, nicotinic acid, nicotinamide, VB7 and VC retained the most after five steps compared to the control. In addition, there was no difference in VB9 contents among different cooking processes compared to the control. Superoxide dismutase (SOD) exhibited a reduction rate of 95.32% and peroxidase (POD) 97.13% after the stir-frying process. 相似文献
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Isolation and identification of two major acylated anthocyanins from purple sweet potato (Ipomoea batatas L. cultivar Eshu No. 8) by UPLC‐QTOF‐MS/MS and NMR 下载免费PDF全文
Jiu‐Liang Zhang Qing Zhou Zi‐Cheng Zhang 《International Journal of Food Science & Technology》2018,53(8):1932-1941
In recent years, researches on the isolation and preparation of monomeric anthocyanins have intensified because of the requirements of quantitative and structure–bioactivity relationship analyses. However, simple and effective methods about the scale of monomeric anthocyanins from the natural purple sweet potato powder are rarely reported. In this study, high molecular weight acylated monomeric anthocyanins were isolated from purple sweet potato (Ipomoea batatas L. cultivar Eshu No. 8) via the combination of column chromatography and semi‐preparative HPLC technology and identified mainly by ultra‐high‐performance liquid chromatography quadrupole time‐of‐flight tandem mass spectrometry/mass spectrometry (UPLC‐QTOF‐MS/MS) and 1H and 13C nuclear magnetic resonance (NMR). Two major acylated anthocyanins were unambiguously determined as peonidin 3‐O‐(6‐O‐(E)‐caffeoyl‐(2‐O‐(6‐O‐p‐hydroxybenzoyl)‐β‐D‐glucopyranosyl)‐β‐D‐glucopyranoside)‐5‐O‐(β‐D‐glucopyranoside) and peonidin 3‐O‐(6‐O‐(E)‐caffeoyl‐(2‐O‐(6‐O‐(E)‐feruloyl)‐β‐D‐ glucopyranosyl)‐β‐D‐glucopyranoside)‐5‐O‐(β‐D‐glucopyranoside). The results of this study may help promote the purification of high molecular weight acylated anthocyanins from purple sweet potato as well as from other plant materials in nature. 相似文献
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目的探究1-甲基环丙烯(1-methylcyclopropylene,1-MCP)结合不同保鲜袋对叶用甘薯茎尖贮藏品质的影响,筛选最适的保鲜方式。方法以叶用甘薯茎尖为材料,经0.91μL/L1-MCP处理24h后结合聚乙烯(PE)或微孔膜(WK)保鲜袋包装,在5℃下进行贮藏,分别于0、3、6、9、12 d时对其失重率、色差、黄化率、呼吸强度、乙烯释放量、多酚氧化酶活性等指标进行测定。结果贮藏12 d后, 1-MCP+PE, 1-MCP+WK处理组的失重率分别为3.43%,2.72%,显著低于未经1-MCP处理组(P0.05),说明1-MCP处理能够有效抑制叶用甘薯茎尖失水; 1-MCP+WK处理下的L值为33.9,高于其余3种处理,表明该处理能够更好的保持叶用甘薯茎尖的亮度和新鲜感。此外,1-MCP结合保鲜袋处理能够减弱呼吸作用,降低乙烯释放量及多酚氧化酶活性。结论1-MCP处理并结合PE膜或者微孔膜包装对叶用甘薯茎尖具有良好的保鲜效果,可以有效延长其贮藏期。 相似文献
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Ildephonse Habinshuti Miao Zhang Hong-Nan Sun Tai-Hua Mu 《International Journal of Food Science & Technology》2021,56(11):6086-6099
Effects of ultrasound (US)-assisted enzymatic hydrolysis and different monosaccharides (arabinose; xylose, XY; galactose and glucose) on peptide structure, antioxidant activities and flavour characteristics of Maillard reaction products (MRP) from sweet potato protein hydrolysates were investigated. US markedly enhanced the MR progress, and USXY showed the lowest pH value of 5.04, the highest browning intensity and fluorescence intensity (P < 0.05). FTIR results revealed significant peptide structure changes in USXY, USAR and USGA compared to other samples. USXY exhibited the highest Oxygen radical absorbance capacity (ORAC) value of 109.15 µg TE/mL, followed by USGA and USAR (94.07 and 93.41 µg TE/mL), respectively (P < 0.05). USXY and USAR showed different aroma features as compared to other MRP (P < 0.05). In addition, US enhanced umami, sweetness and sourness attributes and reduced bitterness of all MRP. USXY exhibited the highest umami intensity score (7.4), followed by USGA (7.3) and USAR (7.2), respectively. Partial least square regression analysis showed that the stronger umami taste was strongly correlated to aldehydes, thiophenes, MW 1000–3000 and 500–1000 Da peptides. Thus, US-assisted enzymatic hydrolysis and MR with xylose (XY) could be a promising way to produce natural flavouring with improved antioxidant activity. 相似文献
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Jiayi Su Chang Tan Yang Gao Ying Feng 《International Journal of Food Science & Technology》2021,56(4):1896-1904
Liquid chromatography coupled with tandem mass spectrometry (LC–MS/MS) was employed to investigate free phenols that were released from purple sweet potato (PSP) by alkaline, acid and enzymatic hydrolysis. Four phenolic acids, including ferulic, isoferulic, 4-hydroxybenzoic and caffeic acids, were identified. Based on their effects on the characteristics of purple sweet potato starch (PSPS), the four phenolic acids were studied. Furthermore, scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FT–IR) and X-ray diffraction (XRD) techniques were employed to explore the microstructures of the complexes of the phenolic acids and PSPS. The obtained results demonstrated that the pasting, thermal, retrogradation, as well as digestive properties of PSPS were all influenced by the phenolic acids which interacted with PSPS through noncovalent hydrogen bonds. The influence of the four phenolic acids on the properties of PSPS was in the descending order: 4-hydroxybenzoic acid > ferulic acid > caffeic acid > isoferulic acid. 相似文献
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Measurement of vertical and horizontal vibrations of a probe for acoustic evaluation of food texture
Two‐dimensional (vertical and horizontal) vibrations of a wedge‐type probe upon food rupture were evaluated separately using two accelerometers placed perpendicular to a guide rod of a swing‐arm device for texture evaluation of the flesh of three varieties of apples and three types of potato chips. Voltage signals from the accelerometers were filtered using a half‐octave band‐pass filter. The energy texture index (ETI), based on kinetic energy of the vertical or horizontal probe vibrations, was calculated over low to high frequency bands (no. 1–21). The spectra for the flesh of the three varieties of apples included two common peaks for vertical ETI at band no. 11 (1,120–1,600 Hz) and 19 (17,920–25,600 Hz) and horizontal ETI at band no. 1 (0–10 Hz) and 15 (4,480–6,400 Hz). The spectra for the three types of potato chips had a common ETI peak at band no. 11 (1,120–1,600 Hz) for horizontal ETI and at no. 15 (4,480–6,400 Hz) for vertical ETI. The three apple varieties gave rise to different intensities of vertical and horizontal ETIs while the two peaks were maintained. The thick potato chip type had higher vertical and horizontal ETIs than the thin and soft varieties in most bands; however, the thin type had the highest vertical ETIs only in lower bands (0–200 Hz). The soft type had the lowest vertical and horizontal ETI. The above results suggest that different food textures can be distinguished by two‐dimensional vibration analyses of probe insertion into a food sample based on frequency bands. 相似文献