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Numerical Simulation and Experimental Validation of a Vibrating Screen for the Sieving of Chamomile (matricaria Chamomilla L.) 洋甘菊振动筛筛分的数值模拟及实验验证
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187047
A. Tamborrino, C. Perone, R. Romaniello, B. Bianchi, A. Berardi, A. Leone
Chamomile (Matricaria chamomilla L.) dried flowers contain a large number of interesting biologically active compounds which make it an important medicinal herb. In order to preserve the commodity quality and the biologically active compounds of chamomile, the correct management of the chamomile processing process coming from the field is fundamental. An important phase of the chamomile process is the final sieving of the dried chamomile in which the intact flower heads are separated from the other parts of the flower. In this study a simulation of a vibrating screen machine was carried out in order to find the best kinematical parameters that allow to improve efficiency during the sieving process of chamomile. The study of the movement kinematics provides the acceleration of the vibrating screen depending on its geometric and mechanical characteristics. The frequencies and amplitudes of the vibrations transmitted to the screen were estimated in the main directions, and the optimal parameters were evaluated to guarantee high sieving efficiency and reliable productivity of the machine. To validate the modelling experimental tests were performed by installing three tri-axial accelerometers on the mobile frame of the machine, in order to obtain an accurate measurement on the three reference axes. The comparison of the measured values with the simulated ones demonstrated the suitability of the numerical simulation and its ability to estimate the process performance. Finally, experimental tests demonstrated that by using the optimal sieving frequency a significant reduction of waste was possible, with a consequently increase in the fraction of dried whole and intact flower.
洋甘菊(Matricaria chamomilla L.)干花含有大量有趣的生物活性化合物,使其成为重要的草药。为了保证洋甘菊的商品质量和生物活性成分,正确管理洋甘菊产地加工过程至关重要。洋甘菊加工的一个重要阶段是干燥洋甘菊的最后筛分,其中完整的花头与花的其他部分分离。为了找到提高洋甘菊筛分效率的最佳运动参数,对振动筛机进行了仿真研究。运动运动学的研究提供了根据其几何和机械特性的振动筛加速度。在主要方向上估计了传递到筛的振动频率和振幅,并评估了最优参数,以保证筛分效率高,生产率可靠。为了验证模型的正确性,在机器的移动机架上安装了三个三轴加速度计,以获得三个参考轴上的精确测量值。实测值与模拟值的比较证明了数值模拟的适用性及其对工艺性能的估计能力。最后,实验测试表明,通过使用最佳筛分频率,可以显著减少浪费,从而增加干燥整花和完整花的比例。
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引用次数: 1
Optimization of Mild Extraction Methods for the Efficient Recovery of Astaxanthin, a Strong Food Antioxidant Carotenoid from Microalgae 微藻中强抗氧化剂类胡萝卜素虾青素的温和提取工艺优化
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187026
M. Chronis, Vasiliki Christopoulou, S. Papadaki, Marina Stramarkou, M. Krokida
Microalgae represent an important source of bioactive compounds for food applications. In this study, multifunctional extracts from Haematococcus pluvialis (H. Pluvialis) microalga have been developed in order to be used as food additives. Total extracts were recovered by ultrasound assisted extraction using eco-friendly and food grade solvents. Five different ratios ranging from 1/100 to 1/5 g biomass/ mL solvent were studied in different ultrasound intensities in order to optimise the extraction of carotenoids, especially of astaxanthin. The produced extracts were analysed using High Pressure Liquid Chromatography (HPLC-DAD) and UV-Vis spectroscopy techniques. Acetone was the most efficient solvent for the extraction of carotenoids in all tested ratios. However, D-limonene and medium chain triglycerides extracts also gave a satisfying recovery of carotenoids. D-limonene was the preferred solvent since extracts with high amounts of carotenoids were recovered, permitting their direct use in food products and avoiding further condensation steps.
微藻是食品中生物活性化合物的重要来源。本研究从雨红球菌(H. pluvialis)微藻中提取多功能提取物,开发用于食品添加剂。总萃取物采用超声波辅助萃取,采用环保型和食品级溶剂回收。为了优化类胡萝卜素,特别是虾青素的提取,研究了不同超声强度下,5种不同比例(1/100 ~ 1/5 g生物质/ mL溶剂)的提取效果。采用高压液相色谱(HPLC-DAD)和紫外-可见光谱技术对提取的提取物进行分析。丙酮是提取类胡萝卜素最有效的溶剂。然而,d -柠檬烯和中链甘油三酯提取物也有令人满意的类胡萝卜素回收率。d -柠檬烯是首选的溶剂,因为含有大量类胡萝卜素的提取物被回收,允许它们直接用于食品中,避免进一步的冷凝步骤。
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引用次数: 4
Incorporation of Electromagnetic Fields as an Alternative Technology to Increase Starch Production in Corn Crops 利用电磁场技术提高玉米淀粉产量的研究
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187021
Deivis Suárez-Rivero, Olga Marin-Mahecha, Jannet Ortiz-Aguilar, A. Puentes, Maikel Suarez-Rivero, T. Guzmán-Hernández
During the last decades, the production of fuels derived from agricultural products called agrofuels or biofuels has been promoted as an alternative to high oil prices and pollution due to carbon dioxide emanating from the primary sources found for that purpose. In this sense, corn is part of the cereals most used in the production of bioenergy, likewise, it is recognized as the most productive vegetable species since antiquity. In the previous context, this project evaluated the performance of starch, as well as the physical-chemical characteristics of corn grains that were subjected to electromagnetic fields. For this, the content of protein, fiber, fiber in acidic detergent, fiber in neutral detergent, fat and nitrogen was determined by official methods 08-01, 46-13 and 30-25 of the AACC. Alike, by optical microscopy, the starch granule was morphologically characterized, with an Accu-scope 3000-led-40 optical microscope with a digital camera Aptina CMOS Sensor of 14 megapixels. For the microscopic observation, suspensions of starch in excess of water were prepared, taking them to a slide, after, covered by cover-object and observed at 100, 400 and 1000 times. The starch yield was determined gravimetrically with soaking in ethyl ether and washing in 96 % ethanol in 40, 100 and 200 U.S. sieves to collect the precipitated starch eliminating the excess of the reagent by evaporation at room temperature. The field and laboratory experiments were carried out at the Fundacion Universitaria Agraria de Colombia – UNIAGRARIA, with Porva corn, harvesting until the grain matured (168 days after sowing). For this, it was taken into account that the seeds, before sowing, had been treated with electromagnetic fields at intensities of L1-23 µT, L2-70 µT and L3-118 µT; Electromagnetic field intensities or flux density (in microtesla, µT) were created artificially from the interconnection of electronic devices that carry electrical charges that act as energy sources; moreover, it was observed that with the application this force, the recovery (yield) in the starch doubled without affecting the characteristics of the compound. Finally, the statistical analyzes were performed in the statistical package Statgraphics 5.1Plus, developing a simple variance analysis and a multiple range test.
在过去的几十年里,从农产品中提取燃料的生产被称为农业燃料或生物燃料,作为高油价和由于为此目的而发现的主要来源产生的二氧化碳所造成的污染的替代品而得到推广。从这个意义上说,玉米是用于生产生物能源的谷物的一部分,同样,它被认为是自古以来产量最高的蔬菜品种。在之前的背景下,本项目评估了淀粉的性能,以及玉米籽粒在电磁场作用下的物理化学特性。为此,采用AACC官方方法08-01、46-13和30-25测定了蛋白质、纤维、酸性洗涤剂中纤维、中性洗涤剂中纤维、脂肪和氮的含量。同样,利用Accu-scope 3000-led-40光学显微镜和1400万像素的Aptina CMOS传感器数码相机,对淀粉颗粒进行了形态表征。显微镜观察时,制备淀粉的过水悬浮液,置于载玻片上,用盖物覆盖,分别在100、400、1000次下观察。采用重量法测定淀粉得率,分别用40、100和200个美国筛子用乙醚浸泡和96%乙醇洗涤,收集沉淀淀粉,室温蒸发去除试剂的过量。田间和实验室试验在哥伦比亚农业大学基金会(UNIAGRARIA)进行,波尔瓦玉米收割至籽粒成熟(播种后168天)。为此,考虑到种子在播种前已经过L1-23µT、L2-70µT和L3-118µT强度的电磁场处理;电磁场强度或磁通密度(以微特斯拉,µT为单位)是由携带电荷作为能量源的电子设备的互连人工产生的;此外,还观察到,在施加这种力的情况下,淀粉的回收率(收率)增加了一倍,而不影响化合物的特性。最后,在统计软件包Statgraphics 5.1Plus中进行统计分析,进行简单方差分析和多极差检验。
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引用次数: 0
Evaluation of the Novel Dehydration Concept for Wild Multi Floral Honey in Vietnam 越南野生多花蜂蜜脱水新概念的评价
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187055
T. T. Dang, D. Pham, N. Phạm, Ngoc Ha Vu, Thi To Quynh Cung, Minh Tan Nguyen
Dehydration of honey is an essential step during honey production in tropical countries to prevent rapid deterioration in quality because of the fermentation. In this study, honey dehydration at atmospheric pressure and temperatures of 36°C, 42°C, and 52°C in a pilot dehydration plant based on JEVA concept was carried out to reduce the moisture content of honey to below 17%. Honey dehydration at a temperature range of 36°C - 42°C achieved a high dehydration rate and low energy simultaneously due to integrating a heat pump into the processing loop. The temperature range of 36°C - 42°C was found out to be the most favourable processing temperature for honey dehydration since at these operational conditions, minimal colour degradation of honey, a low decline in diastase number and high retention of TPC and TFC (87.0% - 88.2% and 74.8% - 80.6%) were achieved. Moreover, honey samples dehydrated at 36°C and 42°C preserved antibacterial activity for strains of MRSE, Salmonella Typhimurium, Proteus Vulgaris, and Pseudomonas aeruginosa compared to raw honey. Under similar operational conditions, the proposed dehydration plant has been found to be better than that of other honey dehydrators reported in the literature in terms of dehydration rate, energy consumption, and lighter impacts on physiochemical characteristics.
在热带国家,蜂蜜脱水是蜂蜜生产过程中必不可少的步骤,以防止因发酵而导致质量迅速恶化。本研究在一个基于JEVA概念的中试脱水装置中,对蜂蜜在常压、36℃、42℃和52℃的温度下进行脱水,将蜂蜜的含水率降低到17%以下。在36°C - 42°C的温度范围内,由于在处理回路中集成了热泵,蜂蜜脱水同时实现了高脱水率和低能耗。在36℃~ 42℃的温度范围内,蜂蜜的颜色降解最小,淀粉酶数量下降低,TPC和TFC的保留率高(87.0% ~ 88.2%和74.8% ~ 80.6%)。此外,在36°C和42°C脱水的蜂蜜样品与生蜂蜜相比,对MRSE、鼠伤寒沙门氏菌、普通变形杆菌和铜绿假单胞菌的抗菌活性保持不变。在类似的操作条件下,所提出的脱水装置在脱水率、能耗和对物理化学特性的影响方面优于文献中报道的其他蜂蜜脱水装置。
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引用次数: 0
Comprehensive Mathematical Model for Freezing Time Prediction of Finite Object 有限物体冻结时间预测的综合数学模型
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187036
A. Bassani, G. D. Garrido, G. Giuberti, R. Dordoni, G. Spigno
Frozen food sees a continuous increase in consumption thanks to the capability to preserve the organoleptic properties and, at the same time, to increase the shelf-life of the food itself. Therefore, a proper design of the freezing process is crucial and is strictly related to an accurate evaluation of freezing time because this establishes the minimum residence time of the product in a continuous freezer. For this reason, several mathematical models have been proposed and investigated for predicting the freezing time, starting from empirical models (lower accuracy and computational time) up to computational fluid dynamics simulation (higher accuracy and computational time). An excellent compromise between accuracy and computational effort seems to be a model that combines empirical laws for property evaluation and heat diffusion equation solved in one dimension. This model can numerically be solved using the method of lines in which spatial derivatives are discretized by the finite difference method and the resulting system of ordinary differential equations is integrated using an appropriate solver. This work aimed to fill some gaps to develop a comprehensive and more accurate model for freezing time prediction. Indeed, the key idea is to validate a model that could be used to optimize the refrigeration process for energy-saving and be the base for a design of experiment in case of lack of experimental data. The newly developed model includes the evaluation of freezing time for finite food shapes because, in some cases, it is not possible to assume a characteristic direction for heat flux. The property of unfrozen and frozen food (e.g. density, thermal conductivity, apparent specific heat, etc.) are evaluated basing on the principal constituent of food (e.g. water, fiber, protein, etc.), while heat transfer coefficient is evaluated using empirical equations, depending on adimensional numbers. In this way, it is possible to be flexible and not strictly related to the evaluation of the properties of food for each different case. The proposed model was validated with different sets of experimental data related to beef and strawberry pulp freezing. For these cases, the R2 index is equal to 0.982 and 0.996 respectively, showing a good agreement between experimental and predicted data. Finally, a case study of spinach cubes freezing was provided to show the potentiality of the novel model.
冷冻食品的消费量不断增加,这要归功于它能保持食品的感官特性,同时也能延长食品本身的保质期。因此,冷冻过程的适当设计是至关重要的,并且与冷冻时间的准确评估严格相关,因为这确定了产品在连续冷冻室中的最小停留时间。因此,已经提出并研究了几种用于预测冻结时间的数学模型,从经验模型(较低的精度和计算时间)到计算流体动力学模拟(较高的精度和计算时间)。在精度和计算工作量之间的一个很好的折衷似乎是一个模型,它结合了性能评估的经验规律和一维解的热扩散方程。该模型可以用线法进行数值求解,其中空间导数用有限差分法离散,得到的常微分方程组用适当的求解器积分。本工作旨在填补一些空白,建立一个更全面、更准确的冻结时间预测模型。实际上,关键思想是验证一个模型,该模型可以用于优化制冷过程以实现节能,并在缺乏实验数据的情况下作为实验设计的基础。新开发的模型包括对有限形状食物的冷冻时间的评估,因为在某些情况下,不可能假设热流的特征方向。未冷冻和冷冻食品的性质(如密度、导热系数、表观比热等)是根据食品的主要成分(如水、纤维、蛋白质等)来评价的,而传热系数是根据量纲数用经验方程来评价的。这样,就有可能灵活而不严格地与每种不同情况下食品特性的评估有关。用不同的牛肉和草莓果肉冷冻实验数据对模型进行了验证。在这些情况下,R2指数分别为0.982和0.996,表明实验数据与预测数据吻合较好。最后,以菠菜块冷冻为例,验证了该模型的可行性。
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引用次数: 0
Biofungicide for the Control of Botrytis Cinerea and Fusarium Oxysporum: a Laboratory Study 生物杀菌剂防治灰霉病和尖孢镰刀菌的实验室研究
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187087
Karla J. Julcapoma Polo, Heyssy L. Mendoza Campos, C. Olivera, Jorge Jave Nakayo, Jhonny W. Valverde Flores
The use of fungicides based on plant extracts for the inhibition of phytopathogens has become a sustainable alternative for the environment. In this sense, research has developed biofungicides based on extracts of Allium cepa (A. cepa), Allium sativum (A. sativum), Zingiber officinale (Z. officinale) and Domestic Residual Oil (DRO) for the inhibition of Botrytis cinerea (B. cinerea) and Fusarium oxysporum (F. oxysporum). The inhibition of the two phytopathogenic fungi was evaluated in vitro, measuring the growth of mycelium of the fungi inoculated in the potato dextrose agar (PDA) culture medium, subjected to four treatments with three different doses (10, 15 and 20 %). The treatment that totally inhibited the mycelial growth of B. cinerea and F. oxysporum was the biofungicide composed by Z. officinale and domestic residual oil with a dose of 15 %. Finally, it is concluded that the use of the biofungicide is favorable for the control of fungi and could be used as an environmentally friendly alternative.
利用基于植物提取物的杀菌剂来抑制植物病原体已成为一种可持续的环境替代品。从这个意义上说,研究开发了以大蒜(Allium cepa)、大蒜(Allium sativum)、生姜(zz . officinale)和国产残油(DRO)提取物为基础的生物杀菌剂,以抑制番茄灰霉病(B. cinerea)和尖孢镰刀菌(F. oxysporum)。在马铃薯葡萄糖琼脂(PDA)培养基中接种3种不同剂量(10%、15%和20%)的真菌,测定其菌丝体的生长情况,对两种植物病原真菌进行体外抑制。完全抑制灰霉菌和尖孢镰刀菌菌丝生长的处理是由牛蒡子和家蝇残油组成的生物杀菌剂,剂量为15%。最后得出结论,生物杀菌剂的使用有利于真菌的控制,可以作为一种环境友好的替代品。
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引用次数: 1
Financial Sustainability and Profitability of Supercritical CO2 Pasteurization of Liquid Products: a Case Study 液体产品的超临界CO2巴氏灭菌的财务可持续性和盈利能力:一个案例研究
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187059
S. Gallinaro, A. Zambon, J. Clavier, Marina Bertolini, Riccardo Zulli, L. Greco, J. Fort, S. Spilimbergo
This work presents an analysis of a supercritical CO2 (SC-CO2) pasteurization process, focusing on the financial and economic parameters that make the process sustainable at an industrial level. A small company processing 5,000,000 bottles of apple juice per year has been chosen as a case study. Investment and operating costs have been estimated based on data collected from the market and the relevant economic literature. The financial sustainability assessment was performed through the Discounted Cash Flow methodology, proving that SC-CO2 pasteurization is profitable on a 10-year horizon. The Net Present Value is strictly positive and the Internal Rate of Return higher than the cost of funding. The sensitivity analysis shows the robustness of this study to possible changes in the model parameters. Overall, this work demonstrates SC-CO2 pasteurization to be profitable and, considering the current growth of the high-nutritional value fruit juice market, it suggests positive financial returns for both incumbents and new entrants.
这项工作提出了超临界二氧化碳(SC-CO2)巴氏灭菌过程的分析,重点是使该过程在工业水平上可持续发展的财务和经济参数。一家每年加工500万瓶苹果汁的小公司被选为案例研究。投资和运营成本是根据从市场和相关经济文献收集的数据估算的。通过贴现现金流方法进行财务可持续性评估,证明SC-CO2巴氏灭菌在10年内是有利可图的。净现值严格为正,内部收益率高于融资成本。敏感性分析表明,本研究对模型参数可能发生的变化具有稳健性。总的来说,这项工作表明SC-CO2巴氏灭菌是有利可图的,考虑到目前高营养价值果汁市场的增长,它表明现有企业和新进入者都有积极的财务回报。
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引用次数: 0
Extraction of Essential Oil from Ultrasound Pre-treated Citronella Grass (cymbopogon Nardus) Leaves by Hydro-distillation Method 超声波预处理香茅叶中精油的水蒸馏法提取
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187108
A. C. Kumoro, D. H. Wardhani, D. S. Retnowati, K. Haryani, Sri Yustika, Tri A. Fajar
The global demand on essential oil derived from citronella grass (Cymbopogon nardus) leaves as fragrances, aroma and remedies ingredients has been steadily increasing towards commercial scale for decades. Therefore, a study to enhance citronella grass essential oil production capacity through ultrasound pre-treatment is performed. This study investigated the effect of various operating parameters, such as leaf particle size (ground, 5 mm and 10 mm), ultrasound pre-treatment time (10, 20 and 30 min) and the leaf particle mass to extracting water volume (SW) ratio (1:4.0 to 1:12.0) on the essential oil yield. The chemical and physical properties of the citronella oil, namely bioactive constituents, specific gravity, refractive index and colour, were also determined. The experimental results indicate that increased ultrasound pre-treatment time and S/W ratio promoted to the enhancement of oil yields by up to 56.94 % and 19.59 %. The GC-MS analysis proved that citronella oil contains mainly citronellal, geraniol, neral and geranial. Physical properties evaluation also revealed that the specific gravity, refractive index and colour of the extracted citronella oil were of acceptable ranges. The results indicated that the increase of S/W ratio and ultrasound pre-treatment time potentially increase the extraction yield. This study suggests that the combined ultrasound pre-treatment and hydro-distillation is a promising method for extracting high quality citronella oil and could be implemented to scale-up the citronella oil production capacity.
几十年来,全球对香茅叶精油作为香料、香气和药物成分的需求稳步增长。因此,本研究通过超声预处理提高香茅草精油的生产能力。研究了叶粒度(磨碎、5 mm、10 mm)、超声预处理时间(10、20、30 min)、叶颗粒质量与提取水量(SW)比(1:4.0 ~ 1:12.0)等操作参数对挥发油得率的影响。还测定了香茅油的化学和物理性质,即生物活性成分、比重、折射率和颜色。实验结果表明,增加超声预处理时间和信噪比对原油收率的提高效果分别为56.94%和19.59%。GC-MS分析证实香茅油主要含有香茅醛、香叶醇、木犀草醛和香叶醛。物理性质评价表明,提取的香茅油的比重、折射率和颜色均在可接受范围内。结果表明,增加超声前处理时间和S/W比有可能提高提取率。本研究表明,超声预处理与水蒸馏相结合是一种很有前途的提取优质香茅油的方法,可用于扩大香茅油的生产规模。
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引用次数: 5
Creating Incremental Revenue from Industrial Cherry Wastes 从工业樱桃废料中创造增量收入
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187093
S. Bagheri, M. Alinejad, M. Nejad, B. Aliakbarian
An increase in the production rate of cherry and cherry products has led to considerable amounts of waste that accumulates rapidly especially during the harvest season. The waste including pits is used as fuel, fertilizer, and partly discarded in the environment. Although the cherry fruit is shown to be a rich source of polyphenols, there is limited information about the polyphenol content of the waste, especially the pits. This study aims to integrate a sequence of novel processing technologies (extraction and encapsulation) for the valorization of cherry pits, i.e. turn them into valuable antioxidant products that can be used in healthcare, cosmetics, and packaging applications. The operative parameters of the extraction process to obtain the maximum polyphenols and encapsulation to protect the extracts were optimized. The results of this study confirmed the feasibility of the extraction and encapsulation to recover a notable concentration of polyphenols with enhanced antioxidant properties. These antioxidants can be used as antibacterial compounds to develop active packaging.
樱桃和樱桃制品产量的增加导致了相当数量的废物,特别是在收获季节迅速积累。包括坑在内的废物被用作燃料、肥料,部分被丢弃在环境中。虽然樱桃果实被证明是多酚的丰富来源,但关于废物,特别是果核中多酚含量的信息有限。本研究旨在整合一系列新的加工技术(提取和封装),使樱桃核增值,即将其转化为可用于医疗保健,化妆品和包装应用的有价值的抗氧化剂产品。对提取工艺参数进行优化,以获得最大多酚含量,并对提取物进行包封保护。本研究的结果证实了提取和包封的可行性,以回收显著浓度的多酚,增强抗氧化性能。这些抗氧化剂可作为抗菌化合物开发活性包装。
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引用次数: 2
Design of Thickened Fluids Rich in Proteins Intended for Dysphagia Management 用于吞咽困难管理的富含蛋白质的增稠液体的设计
Q3 Chemical Engineering Pub Date : 2021-07-01 DOI: 10.3303/CET2187002
L. Piazza, E. Masseroni
Results of the design of food products that behave as structured fluids and that deliver attributes tailored for dysphasic people are presented in the paper. Dysphagia refers to any disruption in the swallowing processes. Dietary strategies for dysphagia management may include altering food textures and modifying liquid consistencies, while maintaining a high nutritive profile and acceptable sensory attributes. Products presented in the paper are designed by taking into account sustainability criteria. Further knowledge is needed at the product’s mesoscale to improve physical behaviour of the designed structured fluids.
本文介绍了食品产品的设计结果,这些产品表现为结构化流体,并为口吃患者提供量身定制的属性。吞咽困难是指吞咽过程中的任何中断。控制吞咽困难的饮食策略可能包括改变食物质地和改变液体浓度,同时保持高营养和可接受的感官属性。本文介绍的产品是通过考虑可持续性标准来设计的。需要进一步了解产品的中尺度,以改善所设计的结构流体的物理行为。
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引用次数: 0
期刊
Chemical engineering transactions
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