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1.
An effort was made to understand the impacts of dried cherry pomace (by-product of cherry juice processing) inclusion into corn starch extrudates on their direct expansion characteristics. The effect of pomace particle sizes (whole unfractionated (<125 to >500 μm), <125, 125–250, 250–500, and >500 μm) and levels of pomace inclusion (0, 5. and 15% (w/w)) were specifically investigated. Feed moisture content of 15.5 ± 0.5% (w.b.) and the extruder barrel temperature of 140 °C were kept constant with varying extruder screw speed (150, 200, and 250 rpm). The radial expansion ratio (ER) increased with 5% pomace level of inclusion compared with control but decreased significantly (p < 0.05) at 15% inclusion. Particle sizes significantly affected ER (p < 0.05) with smaller particle sizes resulting in increased ER at all levels of pomace. Adding cherry pomace significantly decreased water absorption index (WAI) and water solubility index (WSI) with smaller particles leading to higher WSI. Extrusion process did not reduce the total phenolic content (gallic acid equivalents). Inclusion of the smallest particle size (<125 μm) cherry pomace at 5% level of inclusion yielded extrudates with the highest expansion ratio among all treatments, including the control. The scanning electron images suggested improvements in the extrudate surface and the internal cell structures. The results indicated the presence of active interactions between the cherry pomace and starch during the expansion process which is not present as an inert material.  相似文献   

2.
Superfine grinding technology is a new type of food processing that is employed to produce powders with outstanding properties such as high solubility, dispersion, adsorption, chemical reactivity and fluidity. The objective of this work was to study the superfine grinding technology on the silver carp bone and to optimize the operational parameters. The optimum processing conditions of superfine grinding were: feeding pressure of 0.85 MPa, grinding pressure of 1.0 MPa, feeding rate of 0.0325 g/s, feeding particle size of 150-300 μm and one pass through the grinder. Silver carp bone powder with average particle size (D50) of 7.65 μm was produced at these conditions. It was found that the smaller particle size of the powder, the higher its fluidity, solubility, solubility of protein, electric conductivity and water holding capacity of the powder were. So the quality of the products produced by the superfine grinding technology was said to be improved.  相似文献   

3.
The aims of the present study were to prepare different-sized red ginseng powders and investigate the particle size effect on the release property of ginsenosides in in vitro digestion conditions. Ultrafine powder showed bimodal particle size distribution with a large peak at around 100 μm and small peak at around 10 μm, differently from fine powder showing unimodal distribution at 100 μm. The specific surface areas of fine- and ultrafine powders were 48.72 ± 6.41 and 86.74 ± 5.96 m2/g, respectively. Time-dependent release property of the powders in the simulated gastrointestinal fluids was determined by quantifying ginsenoside Rg1 released. The initial and final concentrations of ginsenoside Rg1 released was higher in ultrafine powder than fine one. It is expected that particle size reduction and corresponding increase in the specific surface area have a potential to improve the release of ginsenosides in the gastrointestinal tract and enhance the chances to be absorbed in human body.  相似文献   

4.
Pomegranate peel powders were prepared by superfine grinding, whose effects were investigated on the composition, functional and antioxidant properties of the pomegranate peel products. Fluidised bed jet milling technology was used to process superfine pomegranate peel powder. The physical–chemical properties of coarse powder A (D50 = 413.4 μm) and B (D50 = 197.1 μm), fine powder C (D50 = 142.6 μm) and D (D50 = 41.2 μm), superfine powder E (D50 = 7.68 μm) and raw material powder (RMP) (D50 = 352.2 μm) were investigated in this study. SEM images revealed the shape and surface morphology of six pomegranate peel powders. The physical determinations showed that the smaller the powder particle size was, the greater the surface area (from 0.214 to 1.597 m2 g?1) and bulk density (from 0.653 to 0.751 g mL?1) were, the smaller the angles of repose (from 51.69° to 38.74°) and slide (from 48.32° to 34.18°) were. The water holding capacity (WHC), water‐solubility index (WSI), polyphenols and flavonoids release were significantly improved as the size of pomegranate peel particle decreased. The results of FTIR and UV indicated that grinding process would not influence chemical composition of pomegranate peel. Vitamin C (VC) and butylated hydroxytoluene (BHT) were used in DPPH scavenging activity determination, and DPPH scavenging activity was A < RMP < BHT < B < C < D < E < VC.  相似文献   

5.
探讨超微粉碎对不同食物来源花色苷体外模拟消化生物可接受率的影响。选择蓝莓、紫甘蓝、紫番薯和黑米分别作为浆果、蔬菜、薯类和谷物的代表性食物,充分干燥后进行分级粉碎,得到粗粉和超微粉,测定粉体粒径分布和营养成分;经过模拟胃肠消化后利用高相液相色谱法检测消化液花色苷峰面积,计算得到花色苷生物可接受率。与粗粉相比,超微粉粒径分布更加均匀,平均粒径<25μm,主要营养成分含量没有明显差异,而花色苷含量检测值显著升高;超微粉碎能够将花色苷生物可接受率提高23.78%~87.72%,差异均具有统计学意义(p<0.05)。超微粉碎可以解除细胞壁和纤维素等食物基质对花色苷释放的阻碍作用,提高不同食物来源的花色苷生物可接受率。  相似文献   

6.
In this study, response surface methodology was used to optimize the extraction temperature (25–75 °C) and ethanol concentration (0–70 %, ethanol/water, v/v) to maximize the extraction of total phenolic compounds (TPC) from araticum pulp. The efficiency of the extraction process was monitored over time, and equilibrium conditions were reached between 60–90 min. A second-order polynomial model was adequately fit to the experimental data with an adjusted R 2 of 0.9793 (p < 0.0001) showing that the model could efficiently predict the TPC content. Optimum extraction conditions were ethanol concentration of 46 % (v/v), extraction temperature of 75 °C and extraction time of 90 min. Under the optimum conditions, the araticum pulp showed high TPC content (4.67 g GAE/100 g dw) and also high antioxidant activity in the different assays used (46.56 μg/mL, 683.65 μmol TE/g and 1593.72 μmol TE/g for DPPH IC50, TEAC and T-ORACFL, respectively). From our extraction procedure, we successfully recovered a significantly higher amount of TPC compared to other studies in the literature to date (1.5–22-fold higher). Furthermore, TPC and antioxidant activity were present in the fruit in levels that are difficult to find in other common fruits. These results expose a potential approach for improving human health through consumption of araticum fruit.  相似文献   

7.
Non-thermal pasteurization of orange juices using a continuous pressure change technology (PCT) device was investigated on pilot plant scale for the first time. PCT treatment was conducted by pressurizing orange juice and nitrogen at moderately high pressures (P?=?25 or 50 MPa) in a tubular continuous reactor. Abrupt decompression was achieved by a relief valve at the end of the tubular system. As compared to freshly squeezed juice, PCT treatment slightly reduced levels of carotenoids, vitamin C and hesperidin by 19, 5, and 14 %, respectively. Peroxidase was completely inactivated, whereas residual pectin methylesterase activities amounted to 26–27 %. Simultaneously, total aerobic plate counts were substantially reduced by at least 3.4 log10 cfu/mL. The mean volume-weighed particle diameter d 43 was drastically reduced from 652 μm in freshly squeezed juice to 6 and 31 μm at 25 and 50 MPa, respectively. Concomitantly, CIE-L*a*b* color values indicated a brighter and more intense yellow color of PCT-treated juices. While cloud separation in freshly squeezed juice was completed within 3 days, cloud stability in PCT-treated juices was retained for 5 days.  相似文献   

8.
Microparticulated proteins (MPPs) considerably improve the texture, taste and nutritional value of low-fat dairy products. A combination of superfine grinding and heat-shearing treatment was utilized in order to improve the processing adaptability and stability of microparticulated whey protein (MWP). Comparing the mean particle sizes of WPC and MWP with the superfine milled whey protein concentrate (sWPC) and its microparticulated whey protein (sMWP), the sWPC and sMWP were significantly decreased from 49.24 and 13.09 μm to 8.17 and 5.73 μm, respectively (P?<?0.05). Both sWPC and sMWP exhibited higher water-holding capacity (1.9 and 3.69 g/g, respectively), emulsion activity index (146.38 and 128.6 m2/g, respectively), emulsion stability index (29.04 and 6.31, respectively) and viscoelasticity than WPC and MWP. The dispersion stability of sWPC, sMWP and its cream mimetic were also enhanced after superfine grinding treatment. The sMWP dispersion exhibited more stable liquid behaviour characteristics and maintained the creamy mouth feel better than MWP, indicating the higher dispersion stability of sMWP-based cream mimetic. Therefore, the combined superfine grinding and heat-shearing treatment is a promising technique for the production of microparticulated proteins.  相似文献   

9.
The compositional and physicochemical properties of different whey permeate (WPP), demineralised whey (DWP) and skim milk powder (SMP) size fractions were investigated. Bulk composition of WPP and DWP was significantly (P < 0.05) influenced by powder particle size; smaller particles had higher protein and lower lactose contents. Microscopic observations showed that WPP and DWP contained both larger lactose crystals and smaller amorphous particles. Bulk composition of SMP did not vary with particle size. Surface composition of the smallest SMP fraction (<75 μm) showed significantly lower protein (−9%) and higher fat (+5%) coverage compared with non-fractionated powders. For all powders, smaller particles were more susceptible to sticking. Hygroscopicity of SMP was not affected by particle size; hygroscopicity of semi-crystalline powders was inversely related to particle size. This study provides insights into differences between size fractions of dairy powders, which can potentially impact the sticking/caking behaviour of fine particles during processing.  相似文献   

10.
The objective of this study was to study the influence of purification of sour cherry pomace extract on particle size distribution of suspension and on encapsulation efficiency of powders. In addition, antioxidant activity, surface morphology, and color of powder and capsules were determined. Extraction of phenolic compounds was performed at 30 °C with shaking at 70 rpm for 24 h with 1:20 solid–solvent ratio. Ethanol–water (1:1) was used as the solvent. Filtered extract was concentrated in a rotary evaporator and freeze dried to produce extracted phenolic powder (EPP). Purified extracted phenolic powder (PEPP) was obtained by degritting at 10,000 rpm for 2 min and then by freeze drying for 48 h. Purification reduced Sauter mean diameter (D [32]) of concentrated extract from 5.76 μm to 0.41 μm. In encapsulation, two types of coating materials were used. The first one contained 10 % maltodextrin (MD) and 90 % distilled water, while the second one contained 8 % MD, 2 % gum arabic (GA), and 90 % distilled water. Samples were homogenized using ultrasound (160 W, 50 % pulse) for 20 min. Microsuspensions containing EPP had D [32] of 1.65 and 1.61 μm when 10 % MD and 8 % MD-2 % GA aqueous solutions were used for coating, respectively. It was possible to obtain nano-suspensions when purification step was performed. Suspensions prepared with PEPP and 10 % MD and 8 % MD–2 % GA for coating had D [32] of 0.396 and 0.334 μm, respectively. As a result of purification, encapsulation efficiency of the capsules increased significantly from 86.07–88.45 % to 98.01–98.29 % (P?<?0.001).  相似文献   

11.
This study aimed to establish an efficient route for converting blueberry waste material (BWM) into antioxidant-rich powders. Extracts were produced from BWM by an aqueous method using water acidified with citric acid, in the absence or presence of Pectinex Ultra SP-L and Cellubrix. All BWM extracts contained antioxidants including phenolic acids, anthocyanins, and flavonoids (total phenolic content (TPC) 3655–4369 mg gallic acid equivalent (GAE) and total anthocyanin content (TAC) 219–296 mg cyanidin-3-glucoside equivalents (CyGE) per 100 g dry extract). Extractions at 50 °C yielded higher TPC and TAC but lower vitamin C and pectin contents than extractions at 20 °C. Spray-drying BWM extracts produced at 50 °C (no enzymatic treatments) and an encapsulant (alginate or inulin) at an inlet temperature 150 °C and feed temperature 50 °C yielded powders with desired dark purplish blue color, water activity (0.25–0.33), flowability, reconstitution time (23–46 s in water or milk), TPC (25–30 mg GAE/g), TAC (17–20 mg CyGE/g), storage stability, and Bifidobacterium-boosting properties. Enzymatic pretreatments of BWM did not confer any advantages in preserving antioxidants in powder products, suggesting that some intrinsic BWM components (e.g., pectins) may play an important role in the encapsulating process. The use of alginate as the encapsulant/drying aid afforded higher powder yields, superior protection of antioxidants, better stability over a prolonged storage or elevated temperature storage, greater retention of TPC/TAC under simulated gastrointestinal conditions, and greater Bifidobacterium-boosting effects, compared to powders prepared using inulin. Thus, simple aqueous extraction methods and spray-drying technology hold enormous promise for producing antioxidant-rich powders from blueberry processing by-products or waste.  相似文献   

12.
Gluten-free flours blends using chestnut flour (CF) and rice flour (RF) were assayed in order to determine mixing and rheological properties of doughs at 30 °C as well as the thermal behaviour employing heating–cooling temperature steps. CF with different mean particle size (commercial, CCF: 169 μm and low particle size, CF1: 77 μm samples) was employed and blended with RF (46 μm) at several ratios (%) (CCF/RF: 90/10, 80/20, 70/30, 60/40, 50/50; CF1/RF: 25/75, 15/85, 5/95). Doughs from CCF, CF1 and RF flours were employed as reference systems. The rheological characterization of doughs conducted on the rheometer was performed by shear, oscillatory and creep-recovery assays. Rheological properties were significantly modified by flour ratio and by CF particle size. Creep-recovery curves showed that CCF/RF (70/30) and CF1/RF (25/75) improved the doughs elasticity by 41.1 % and 87.5 % compared with CCF and CF1, respectively. Cross, power and Burgers models were used to describe the flow curves, mechanical spectra and creep-recovery behaviour, respectively, of doughs. A mixing rule successfully reproduced the experimental data and fitting parameters of applied models as function of each flour fraction in the blends, except for oscillatory data.  相似文献   

13.
Beverages are an ideal food format to deliver health-promoting polyphenols (PPs) and dietary fibres (DFs) to consumers. In this study, complex beverage systems, smoothies, were formulated containing high concentrations of apple PPs (500 mg per 300 ml beverage), apple fibres of two different particle sizes (AF01, 250 μm; AF09, 300–700 μm; each containing soluble and insoluble fibres), and stabiliser carboxymethylcellulose (CMC; 0.05–2.00 %). The beverages were pasteurised at 85 °C for 15 s, and subjected to total extracted PP content (TEPC) and rheological measurements (viscosity, elastic modulus G′ and viscous modulus G″ at 4, 20, 37 and 60 °C). Scanning electron microscopy (SEM), FT-IR spectroscopy and N2 physisorption measurements on the AF01 and AF09 fibre powders showed that they differed in particle size, yet were similar in particle surface morphology, chemical composition and specific surface area. Characterisation of smoothies prepared from the AF01 and AF09 fibres showed that the particle size of the apple fibres, testing temperature and CMC concentration strongly influenced the extractability of PPs and rheological behaviour of the smoothies. The peak TEPC values of the AF01 and AF09 beverages, 327 and 351 mg catechin equivalent per 300 ml beverage, occurred at 1.50 % and 1.00 % CMC, respectively. The temperature dependence of smoothie viscosity was examined, and an Arrhenius relationship was observed for both the AF01 and AF09 smoothie systems. The stabilising effect of CMC for this type of smoothie beverage was confirmed. CMC concentrations of 1.00–1.50 % afford high extracted PP content, good phase stability and beverage flow properties. These results presented here can be used to guide the development of stable beverages containing relatively high concentrations of PPs and DFs (including both insoluble and soluble).  相似文献   

14.
The combined effects of enzymatic/alkali protein removal treatments and superfine grinding on the characteristics of okara dietary fibre (DF) were investigated. Protein removal could effectively increase the obtained DF content and further enhance water-holding capacity (WHC), swelling capacity (SC) and oil-holding capacity (OHC). The DF with Alcalase treatment and superfine grind through 500-μm mesh size had the highest total dietary fibre, WHC (12.5 g g−1), SC (12.7 mL g−1) and OHC (2.7 g g−1). Decreasing particle size will trigger a redistribution of some fibre composition from the insoluble to the soluble fraction. The WHC and SC of the sieved DFs decreased with reducing mesh size (500–40 µm). The OHC of DF with Flavourzyme treatment reduced with decreasing mesh size (500–100 µm), but improved with mesh size less than 100 µm.  相似文献   

15.
The aim of this study was to investigate the impact of thermal processing (TP) (90 °C, 90 s), high-pressure processing (HPP) (600 MPa, 46 °C, 5 min), and high-pressure homogenization (HPH) (246 MPa, 99 °C, <1 s) on product quality parameters, specifically carotenoid content, and physicochemical attributes of particle size, color, viscosity, total soluble solids, and pH in tomato juice. Unprocessed tomato juice was used as control. The four major species of carotenoids (lycopene, β-carotene, phytoene, and phytofluene) in tomato juice were analyzed by HPLC. The content of total lycopene, all-trans-lycopene, cis-lycopene isomers,  phytoene, and phytofluene, in TP-, HPP-, and HPH-treated tomato juice did not significantly differ from that in unprocessed (control) juice. Significant reduction in β-carotene content was observed after TP treatment but not after HPP and HPH treatments. HPH significantly reduced tomato juice particle volume mean diameter from ~330 μm in control, HPP-, and TP-treated tomato juices to ~17 μm. A concomitant increase in apparent viscosity was observed in HPH-treated juice versus control. HPH-treated juice had increased redness (a*) and yellowness (b*) than that in control and HPP-treated tomato juices. These results indicate that high-pressure-based technologies (HPP and HPH) can preserve carotenoids as well as improve physicochemical properties.  相似文献   

16.
本研究主要以大麦为主要原料,探究不同粒径对超微粉碎大麦粉品质特性的影响.研究结果表明,随着粒径的降低,大麦全粉水分、淀粉含量、溶解性、亮度值及白度值显著增加(P<0.05),而膨润力、吸油性、持水性、峰值黏度和回生值则显著降低(P<0.05).微观结构结果表明,随着粒径的降低,大麦全粉粉体的颗粒形状由圆形或椭圆形转为不...  相似文献   

17.
Structural and rheological characterization of reconstituted hydrogels developed from A. vera non-fibrous alcohol insoluble residue (NFAIR) powder using different methods [viz., shaking (S), heating-shaking (HS), and heating (H)] and concentrations (viz., 0.2–1.6 %, w/v) was carried out. Functional group distribution by FTIR spectroscopy and Congo red (CR) method revealed the presence of acetylated acemannan in A. vera powder. Dynamic oscillation studies of A. vera (NFAIR) fluids at all concentrations of 0.2–1.6 %, w/v, showed gel strength in the order of H > HS > S method. However, in H method, increase in concentration from 0.2 to 1.6 %, w/v showed the conformational transition from semi-diluted solution to weak gel nature. Rheological models described the effect of heating temperatures (HT); 30–90 °C, and times (Ht); 15–60 min on viscoelastic behavior in reconstituted A. vera fluids. The reconstituted A. vera hydrogel prepared with a concentration of 1.6 %, w/v using 50 °C (HT) and 30 min (Ht) condition showed a good agreement with the Power law (storage modulus, G′) and Weak gel model (complex modulus, G*) fitted data (R2 > 0.94) resulting higher viscoelastic moduli intercepts; G0 (71.5 Pa s n), G0 (33.5 Pa s n), lower slopes; n′ (0.22), n″ (0.06), higher network strength (A F , 121.3 Pa s1/z ) and number of network (z, 5.3) values. The obtained results suggested that heating at 50 °C/30 min can develop aqueous weak gel networks of A. vera with enhanced gel strength which may be utilized as a novel gelling agent for wide variety of targeted applications in food and pharmaceutical sectors.  相似文献   

18.
The effect of the combination of maltodextrin DE 10 (MD) and native agave fructans (FR) in concentrations of 0, 2, and 4% (w/v) on the rheological properties, microstructure, and water sorption of spray-dried chayote and pineapple powders was evaluated. A 10% (w/v) maltodextrin treatment was used as a control to compare treatments added with fructans. The scanning electron micrographs revealed spherical particles in a range from 16 to 105 μm with shrinkage, whereby greater caking and agglomeration occurred among particles in treatments with native agave fructans. The flow behavior of all juices can be described by the Bingham model with low plastic viscosities (0.0026 to 0.0030 Pa s?1); the isotherms of the powders show a sigmoid shape pointing to the easy union of the fructans with water molecules. These types of isotherms are common for non-porous foods, and are indicative of physical adsorption in multi-layers where the adsorbate conserves its identity.  相似文献   

19.
Rye bran is a high-fibre ingredient also containing starch and protein. The aim of this work was to investigate the effects of extrusion processing and bran particle size on the structural and mechanical properties of extruded rye bran. Native rye bran particle size of 750–1,250 μm was milled to produce feed material with three different average particle sizes (coarse, 440 μm; medium, 143 μm; fine, 28 μm). A co-rotating twin screw extruder was used for extrusion with various processing parameters. Extrusion processing did not have a significant (P?<?0.05) effect on soluble dietary fibre (SDF) content but the amount of insoluble dietary fibre (IDF) increased by 7.1–9.5 % in medium- and 11.3–12.3 % in fine-particle-sized rye bran extrudates as compared to the raw material prior to extrusion. Decreasing the particle size of rye bran to 28 μm resulted in lower amounts of IDF and total dietary fibre, but a higher amount of SDF after extrusion compared to coarse-particle-sized rye bran. Decreasing the particle size of rye bran to 28 μm gave more expanded (179–223 %), less hard (145–336 N), more crispy (2.7–7.2?×?10?4) and porous (79.2–83.9 %) extrudates compared to the coarse-particle-sized rye bran extrudates, which were less expanded (151–176 %), harder (210–433 N), less crispy (0.5–2.8?×?10?4) and less porous (64.4–65.1 %). Reduction of the particle size of rye bran significantly (P?<?0.05) increased the crispiness compared to the extrudates made of coarse-particle-sized rye bran. The results demonstrated that the structural and mechanical properties of rye bran extrudates can be improved without starch addition by reducing the particle size of bran.  相似文献   

20.
This study reports the investigation into pectin present in Terminalia ferdinandiana—a native Australian fruit utilised in dietary supplement industry. Citric acid extraction was carried out to extract pectin from two commercially available T. ferdinandiana products—frozen puree and freeze-dried puree powder. The yields of the extracted pectin were measured at various pHs (2.0, 3.0 and 4.0) and times (30, 60 and 120 min) at 75 °C. Pectin yield ranged between 4.8 and 21%. Freeze-dried powder had a higher pectin yield compared to puree. Extraction at pH 3 for 120 min resulted in the highest yield from both puree (15%) and powder (21%). T. ferdinandiana pectins were found to have low methoxyl content with degree of esterification of 35.07 and 34.74% for puree and powder, respectively. Fourier transform infrared spectroscopy confirmed that the extracts were pectin.  相似文献   

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