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1.
Heat-moisture treatment (HMT) changed the morphology and the degree of molecular ordering in lotus rhizome (Nelumbo nucifera Gaertn.) starch granules slightly, leading to some detectable cavities or holes near hilum, weaker birefringence and granule agglomeration, accompanied with modified XRD pattern from C- to A-type starch and lower relative crystallinity, particularly for high moisture HMT modification. In contrast, annealing (ANN) showed less impact on granule morphology, XRD pattern and relative crystallinity. All hydrothermal treatment decreased the resistant starch (from about 27.7–35.4% to 2.7–20%), increased the damage starch (from about 0.5–1.6% to 2.4–23.6%) and modified the functional and pasting properties of lotus rhizome starch pronouncedly. An increase in gelatinization temperature but a decrease in transition enthalpy occurred after hydrothermal modification, particularly for hydrothermal modification involved with HMT. HMT-modified starch also showed higher pasting temperature, less pronounced peak viscosity, leading to less significant thixotropic behavior and retrogradation during pasting-gelation process. However, single ANN treatment imparts a higher tendency of retrogradation as compared to native starch. For dual hydrothermally modified samples, the functional properties generally resembled to the behavior of single HMT-modified samples, indicating the pre- or post-ANN modification had less impact on the properties HMT modified lotus rhizome starch.  相似文献   

2.
Dietary fiber can be obtained by dextrinization, which occurs while heating starch in the presence of acids. During dextrinization, depolymerization, transglycosylation, and repolymerization occur, leading to structural changes responsible for increasing resistance to starch enzymatic digestion. The conventional dextrinization time can be decreased by using microwave-assisted heating. The main objective of this study was to obtain dietary fiber from acidified potato starch using continuous and discontinuous microwave-assisted heating and to investigate the structure and physicochemical properties of the resulting dextrins. Dextrins were characterized by water solubility, dextrose equivalent, and color parameters (L* a* b*). Total dietary fiber content was measured according to the AOAC 2009.01 method. Structural and morphological changes were determined by means of SEM, XRD, DSC, and GC-MS analyses. Microwave-assisted dextrinization of potato starch led to light yellow to brownish products with increased solubility in water and diminished crystallinity and gelatinization enthalpy. Dextrinization products contained glycosidic linkages and branched residues not present in native starch, indicative of its conversion into dietary fiber. Thus, microwave-assisted heating can induce structural changes in potato starch, originating products with a high level of dietary fiber content.  相似文献   

3.
The aim of the study was to assess the effect of soil type and the application of fertilizer composed of ashes from biomass combustion to potatoes on selected physicochemical, rheological, and thermal properties of potato starches isolated by using the laboratory method. Potatoes were grown in Haplic Luvisol (HL) and Gleyic Chernozem (GC) soil and fertilized with different doses of biomass combustion ash (D1–D6) with different mineral contents. The thermodynamic characteristics of gelatinization and retrogradation were identified by DSC. The analyses of rheological properties included the determination of the gelatinization characteristics by using the RVA method, flow curves, and assessment of the viscoelastic properties of starch gels. It was found that the starches tested contained from 24.7 to 29.7 g/100 g d.m. amylose, and the clarity of 1% starch pastes ranged from 59% to 68%. The gelatinization characteristics that were determined showed statistically significant differences between the starches analyzed in terms of the tested factors. The value of maximum viscosity and final viscosity varied, respectively, in the range of 2017–2404 mPa·s and 2811–3112 mPa·s, respectively. The samples of the potato starches studied showed a non-Newtonian flow, shear thinning, and the phenomenon of thixotropy. After cooling, the starch gels showed different viscoelastic properties, all of which were weak gels (tan δ = G″/G′ > 0.1).  相似文献   

4.
Wheat bread, produced by the single-phase method, is a common food consumed all over the world. Due to changes in lifestyle and nutritional trends, alternative raw materials are sought to increase the nutritional value and improve the taste of daily consumed products. Additionally, customers seek a wide variety of foods, especially when it comes to basic foods. Nuts, such as coconuts or chestnuts, might provide an attractive flavour with benefits to the nutritional quality. In this study, the effect of substituting wheat flour with coconut or chestnut flour (flour contribution level: 5, 10, 15, 30, 50% w/w), was evaluated in terms of the breads specific volume, texture, colour, nutritional composition, and dietary fibre fraction contents. Moreover, a sensory evaluation was conducted to assess potential consumer acceptance. Based on the consumer’s perception, the overall acceptance of bread with 15% w/w of coconut and chestnut flour was in privilege compared to the control sample. As a result, taking all of the tested parameters into account, the breads with 5, 10, and 15% supplementation of chestnut or coconut flour were still of good quality compared to the wheat bread and their fibre content was significantly higher.  相似文献   

5.
Low-calorie and low-fat foods have been introduced to the market to fight the increasing incidence of overweightness and obesity. New approaches and high-quality fat replacers may overcome the poor organoleptic properties of such products. A model of processed cheese spread (PCS) was produced as a full-fat version and with three levels of fat reduction (30%, 50%, and 70%). Fat was replaced by water or by corn dextrin (CD), a dietary fiber. Additionally, in the 50% reduced-fat spreads, fat was replaced by various ratios of CD and lactose (100:0, 75:25, 50:50, 25:75, and 0:100). The effect of each formulation was determined by measuring the textural (firmness, stickiness, and spreadability), rheological (flow behavior and oscillating rheology), tribological, and microstructural (cryo-SEM) properties of the samples, as well as the dynamic aroma release of six aroma compounds typically found in cheese. Winter’s critical gel theory was a good approach to characterizing PCS with less instrumental effort and costs: the gel strength and interaction factors correlated very well with the spreadability and lubrication properties of the spreads. CD and fat exhibited similar interaction capacities with the aroma compounds, resulting in a similar release pattern. Overall, the properties of the sample with 50% fat replaced by CD were most similar to those of the full-fat sample. Thus, CD is a promising fat replacer in PCS and, most likely, in other dairy-based emulsions.  相似文献   

6.
A fast melt tablet (FMT) is well regarded as an alternative delivery system that might help resolve a patient’s non-compliance issue. The main objective of this study was to develop a cocoa butter-based FMT. Additives, namely 5–15% of PEG 6000, beeswax, paraffin wax, and corn starch, were incorporated into the cocoa butter-based FMT to study the effects of these additives with the physical characteristic of a cocoa butter FMT. An optimum-based formulation was chosen according to the desired hardness and disintegration time and the taste masking property achieved with the model drug—dapoxetine. The analysis demonstrated that incorporating beeswax (15%) and paraffin wax (15%) could prolong the disintegration time by at least two-fold. On the contrary, the presence of corn starch was found to cause an increase in the hardness and reduction of the disintegration time. The disintegration mechanism might be presumed due to the synergistic effect of starch swelling and cocoa butter melting. The hardness value and in vitro disintegration time of the optimum formulation were recorded at 2.93 ± 0.22 kg and 151.67 ± 6.98 s. In terms of dissolution, 80% of dapoxetine was released within 30 min and the dissolution profile was comparable to the innovator product. The formulation was palatable and stable for at least 1 year. The exposure of the FMT formulation at 30 °C for 12 months was reported to be stable. Along with the sound palatability profile and high drug load capacity, the current formulation possesses the desired characteristics to be scaled up and marketed.  相似文献   

7.
Fiber-enriched food has numerous health benefits. This study develops functional fiber-enriched pasta (FEP) by partially substituting wheat flour for alcohol-insoluble residue prepared from potato processing byproducts (AIR-PPB) at various particle sizes (PS). The independent variables’ effects, AIR-PPB at 2–15% substitution levels, and PS 40–250 µm were investigated in terms of chemical, cooking, thermal, and sensory properties. AIR-PPB is rich in total dietary fibers (TDF) (83%), exhibiting high water-holding capacity (WHC) and vibrant colors. Different concentrations of AIR-PPB increase TDF content in FEPs by 7–21 times compared to the control pasta (CP). Although the optimal cooking time (OCT) decreases by 15–18% compared to CP, where a lower OCT should reduce cooking time and save energy, cooking loss (Cl) increases slightly but remains within an acceptable range of 8%. Additionally, AIR-PPB altered the texture properties of FEP, with a moderate decrease in mass increase index (MII), firmness, and stickiness. AIR-PPB impairs the gluten network’s structure in pasta due to AIR-PPB’s WHC, which competes with starch for water binding, increasing the starch gelatinization temperature. FEPs show an increased lightness and yellowness and improved sensory properties. Highly acceptable FEPs were obtained for the following substitution levels: FEP11 (AIR-PPB at 2% and PS of 145 µm), FEP9 (AIR-PPB 4% level with PS of 70 µm), FEP6 (AIR-PPB of 4% level with 219 µm PS), and FEP1 (AIR-PPB = 8.5% with 40 µm PS), as compared to other FEPs.  相似文献   

8.
Highlights
  • Cookies with a 4% level of LJ extracts possessed the highest chlorogenic acid content.
  • The addition of higher levels of LJ extracts significantly increased higher antioxidant activity of cookies.
  • Cookies with a 1% level of LJ extracts had the highest sensory score.
AbstractsLonicera japonica Thunb. (LJ), as a Caprifoliaceae family plant, is enriched with polyphenols. Cookies supplemented with LJ extracts have the potential to exert antioxidant activity. However, studies on cookies fortified with LJ extracts are scarcely available. Therefore, the effect of LJ extract addition on cookie phenolic acid content, antioxidant activity, color, texture and the sensory score was firstly evaluated. Results suggest that different levels (1–4%) of LJ extracts significantly increased chlorogenic acid content, ranging from 21.96 to 202.65 μg/g. Cookies with a 4% level of LJ extracts possessed the highest activity of scavenging DPPH free radical activity (63.71 μg Vc/g), ABTS free radical activity (415.10 μg Vc/g), and ferric-reducing power of cookies (169.58 μg Vc/g). Further, a decrease in lightness L* and an increase in redness a* were observed in cookies with LJ extract addition. LJ extract addition lowered the hardness of cookies, and 4% level of LJ extracts increased the crispiness of cookies. Cookies with a 1% level of LJ extracts had a higher overall acceptance score (84.33) than that of other levels. Sensory acceptance played a vital role in the selection of the optimal formulation of cookies. Therefore, LJ extracts at 1% level could be an optimal supplement proportion in cookies and increased the antioxidant activity of cookies.  相似文献   

9.
Two new symmetrical diamines were designed and synthesized having different functional groups such as a pair of phenyl ether linkages, 2,3-diaryl substituted imidazole rings and CF3 groups as pendant, and characterized by FT-IR, 1H and 13C-NMR spectroscopy and elemental analysis. A series of new fluorescent poly(imide-ether)s (PIEs) was prepared by polymerization of the diamines with commercial tetracarboxylic dianhydrides such as pyromellitic dianhydride and 3,3′,4,4′-benzophenone tetracarboxylic dianhydride. The resulting PIEs were amorphous and had intrinsic viscosity [η] in the range of 0.42–0.51 dL/g. The weight average molecular weights (Mw) of these polymers were measured by GPC and were in the range of 28658–35595 g/mol with molecular weight distribution (MWD) of 2.12–2.27. These polymers were readily soluble in a variety of organic solvents and formed low-colored and flexible thin films with cut-off wavelength (λ0) in the range of 385–420 nm, and all PIEs films exhibited high optical transparency. They also possessed good thermal stability with 10% weight loss temperatures (T10%) in the range 486–537°C in N2. The glass transition temperatures (Tg) of PIEs are in the range 251–324°C. These polymers showed fluorescence emission in film and in solution at 459–476 nm with the quantum yields in the range 4–12%.  相似文献   

10.
Stinging nettle (Urtica dioica L.) is a good source of biologically active compounds with proven beneficial health effects. This study aimed to investigate the effect of nettle herb supplementation on chemical composition, including the content of selected minerals and pigments, the in vitro glycemic response, and the cooking and sensory quality of extruded pasta. Tagliatelle-shaped pasta was produced under semi-technical scale by partial replacement of durum wheat semolina with 0, 1, 2, 3, 4, and 5% of lyophilized nettle. The partial substitution with freeze-dried nettle caused a statistically significant (p ≤ 0.05) increase in the content of minerals, especially calcium, iron, potassium, and magnesium in the products. The calcium content in the pasta fortified with 5%-addition of stinging nettle was 175.9 mg 100 g−1 and this concentration was 5.8 times higher than in the control sample. At the same time, high content of chlorophylls and carotenoids (237.58 µg g−1 and 13.35 µg g−1, respectively) was noticed. Enriching pasta with a 0–5% addition of stinging nettle resulted in a statistically significant (p ≤ 0.05) increase in the content of the total dietary fiber (TDF) (from 5.1 g 100 g−1 to 8.82 g 100 g−1) and the insoluble dietary fiber (IDF) (from 2.29 g 100 g−1 to 5.63 g 100 g−1). The lowest hydrolysis index of starch (HI = 17.49%) and the lowest glycemic index (GI = 49.31%) were noted for the pasta enriched with 3% nettle.  相似文献   

11.
A cheap and environment friendly route towards the synthesis of Polyvinyl alcohol/silica hybrid composites is presented. Polyvinyl alcohol/silicate hybrid materials were synthesised in aqueous medium by the sol-gel method using dil HCl (0.5 N) as catalyst and a cost-effective silica source sodium silicate. The synthesis method was aimed at enhancing the rate of co-condensation of silica within the polyvinyl alcohol matrix. Transparent and flexible hybrid films of homogenous thickness were obtained after gelation at 45°C for 24 h and extended drying for another 48 h. The hybrid composites were characterised by fourier transform infrared spectroscopy (FTIR), scanning electron microscopoy (SEM), thermogravimeric analysis (TGA), tensile strength, elongation at break and water uptake measurements. SEM micrographs revealed that silica was dispersed in the PVA matrix without the large aggregation of particles for a molar composition of 0.0004 PVA:0.048 Sodium silicate: 0.004 HCl.  相似文献   

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