An artificial neural network for predicting the physiochemical properties of fish oil microcapsules obtained by spray drying

The aim of this work was to develop an artificial neural network (ANN) to predict the physiochemical properties of fish oil microcapsules obtained by spray drying method. The relation amongst inlet-drying air temperature, outlet-drying air temperature, aspirator rate, peristaltic pump rate, and spraying air flow rate with 5 performance indices, namely capsules’ residual moisture content, particle size, bulk density, encapsulation efficiency, and peroxide value was bridged by using ANN. A multilayer perceptron ANN was developed to predict the performance indices based on the input variables. The optimal ANN model was found to be a 5-10-5 structure with tangent sigmoid transfer function, Levenberg-Marquardt error minimization algorithm, and 1,000 training epochs. This optimal network was capable to predict the outputs with R² values higher than 0.87. It was concluded that ANN is a useful tool to investigate, approximate, and predict the encapsulation characteristics of fish oil.     

Influence of Wall Material and Inlet Drying Air Temperature on the Microencapsulation of Fish Oil by Spray Drying

Several single and composite milk-originated wall materials were used to microencapsulate fish oil via spray drying at various inlet drying air temperatures. Skim milk powder (SMP), whey protein concentrate, whey protein isolate (WPI), 80% WPI?+?20% milk protein concentrate, and 80% WPI?+?20% sodium caseinate (NaCas) were applied as the wall for capsules generated at drying air temperatures of 140, 160, and 180 °C. The higher the drying air temperature, the higher was the particle size, encapsulation efficiency, and peroxide value and the lower was the moisture content and bulk density. The microcapsules prepared with SMP showed the highest encapsulation efficiency and lowest peroxide value for the oil due to the presence of lactose in its chemical composition. Differential scanning calorimetry and Fourier transform infrared analyses indicated the absence of any significant interaction between SMP and fish oil.     

An integrated process for utilization of pomegranate wastes — Seeds

In this work, a new method for pomegranate seeds application was developed based on the ultrasound-assisted extraction of seed oil and its subsequent encapsulation by spray drying. Extraction temperature, solvent/solid ratio, amplitude level, and pulse duration/pulse interval ratio were the factors investigated with respect to extraction yield. Ultrasound was sound to increase extraction yield, but mainly to shorten the treatment time by over 12 times. Different materials were used as encapsulating agents. Ratio of core to wall material, inlet air temperature, drying air flow rate, and feed solids concentration were the factors investigated with respect to encapsulation efficiency. The resulting microcapsules were evaluated in terms of moisture content, bulk density, and rehydration ability. The optimum operating conditions were found to be: wall material, maltodextrin/Tween 80; ratio of core to wall material, 0.23; inlet air temperature, 150 °C; drying air flow rate, 22.8 m³/h; feed solids concentration, 30% (w/w).Industrial relevancePomegranate seeds, a by-product of pomegranate juice and concentrate industries, present a wide range of pharmaceutical and nutraceutical properties. Therefore, the seeds could have more beneficial applications in food industries instead of being used as animal feed or in commercial cosmetic products. In this work, a new method for pomegranate seeds application was developed based on the ultrasound-assisted extraction of seed oil and its subsequent encapsulation by spray drying.     

A Feasibility Study on the Drying of Lime Juice: The Relationship between the Key Operating Parameters of a Small Laboratory Spray Dryer and Product Quality

Concentrated lime juice with 20% total soluble solids was dried using three levels of maltodextrin (40%, 50%, and 60% solid base) and a BüCHI B-190 spray dryer. The drying air temperature and flow rate were 140 °C, 155 °C, and 170 °C and 47.1, 53.5, and 57.8 m³/h, respectively. A total of 27 experiments were conducted (in triplicate) with the feed rate, temperature, and compressed air flow for the atomizer kept constant. Analysis of the data revealed that product recovery increased when the maltodextrin in the feed and drying air flow rate were increased, but the inlet air temperature had no significant (P < 0.05) effect on powder recovery. The moisture content of the powder varied with the maltodextrin level, inlet air temperature, and air flow rate. Using scanning electron microscope images, larger particle size was observed with the increase of maltodextrin concentration. Powder bulk density also increased from 0.41 to 0.68 g/cm³, depending on the level of maltodextrin, whereas the drying air temperature and flow rate were not as effective. The results of this study are beneficial for scaling up the spray drying of lime juice to the food industry.     

A process for turning pomegranate peels into a valuable food ingredient using ultrasound-assisted extraction and encapsulation

A new method for pomegranate peel application in food industries was developed based on the ultrasound-assisted extraction of phenolic compounds and their subsequent encapsulation by spray drying. The effects of various parameters on extraction yield, on encapsulation efficiency/yield, and on the main physical properties of the microcapsules (moisture content, bulk density, rehydration ability) were studied. Ultrasound was found to increase extraction yield, but mainly to shorten the treatment time by over 20 times. The maximum encapsulation efficiency was 99.80% and the optimum operating conditions were found to be: wall material, maltodextrin/whey protein isolate (50:50); inlet air temperature, 150 °C; drying air flow rate, 17.5 m³/h; ratio of wall to core material, 9/1; feed solid concentration, 30% (w/w). The encapsulated phenolic extract was found efficient in improving the shelf life of hazelnut paste, in spite of the limited solubility of the crude extract in such a high lipid content matrix.Industrial relevancePomegranate peels, a by-product of pomegranate juice and concentrate industries, present a wide range of pharmaceutical and nutraceutical properties. Therefore, the peels could have more beneficial applications in food industries instead of being used as animal feed or in commercial cosmetic products. In this work, a new method for pomegranate peel application was developed based on the ultrasound-assisted extraction of phenolics and their subsequent encapsulation by spray drying.     

Changes in the physical properties of honey powder during storage

Honey powders produced by spray drying with the addition of Arabic gum and sodium caseinate were characterised in terms of the influence of storage time on the following physical properties: particle size, moisture content, water activity, bulk density, flowability and hygroscopicity. The storage affected those properties; after 12 weeks of storage, particle size decreased (except Arabic gum powder treated as a control sample), moisture content and water activity increased, hygroscopicity decreased. Changes in bulk density, particle size and moisture content caused the rise of Hausner ratio value; however, the powders were still characterised by a very good flow properties and low cohesiveness. The colour of reconstituted powders was also affected by storage; in most of samples, the darkening, reduction in redness and yellowness were observed. Colour parameters were the most stable in powders obtained with the addition of 2% w/w of sodium caseinate.     

Influence of emulsion composition and inlet air temperature on the microencapsulation of flaxseed oil by spray drying

The objective of this work was to study the influence of some process conditions on the microencapsulation of flaxseed oil by spray drying. The process was carried out on a mini spray dryer and gum Arabic was used as wall material. Seventeen tests were made, according to a central composite design. Independent variables were: inlet air temperature (138-202 °C), total solid content (10-30% w/w) and oil concentration with respect to total solids (10-30% w/w). Encapsulation efficiency, lipid oxidation and powder bulk density were analyzed as responses. Powder morphology and particle size distribution were also analyzed. The feed emulsions were characterized with respect to droplet size and viscosity. Higher solid content and lower oil concentration led to higher encapsulation efficiency and lower lipid oxidation, which was related to the higher emulsion viscosity and lower droplets size. Increasing drying temperature resulted in higher lipid oxidation. Bulk density increased when higher solid content and lower inlet air temperature were used. The particles were rounded and shriveled, and their mean diameter was mainly affected by total solid content.     

响应面试验优化喷雾干燥制备核桃分心木速溶粉及其冲调性分析

以核桃分心木为原料,从分心木速溶粉冲调性的角度出发,采用单因素试验研究喷雾干燥进风口温度、进料流量及热风流量对核桃分心木速溶粉润湿性、分散性、水分含量及颗粒大小的影响,并选择进风口温度、进料速率、热风流量3 个因素,以润湿时间及分散时间为响应值进行响应面优化试验。喷雾干燥制备核桃分心木速溶粉的最优参数为进风口温度170 ℃、进料流量1.8 L/h、热风流量35 m3/h。采用上述实际操作参数重新制作核桃分心木速溶粉样品进行实验,实际测得润湿时间为13.2 s,分散时间为5.8 s,与模型预测值相符。     

均质压力及喷雾干燥温度对鱼油微胶囊化的影响

采用辛烯基琥珀酸酯淀粉Hi-Cap100和葡萄糖浆作为鱼油微胶囊的壁材。研究了不同均质压力下乳化液黏度、粒径和粒径分布规律,考察了不同均质压力下乳化液特性与鱼油微胶囊包埋率、表面油含量之间的相关性,探讨了喷雾干燥温度对包埋率和鱼油过氧化值(POV)的影响。研究结果表明,随着均质压力的增加,乳化液黏度和平均粒径逐渐减小,而粒径分布离散度总体呈下降趋势,在40MPa时最小,说明此时粒径分布均一性最佳;喷雾干燥温度增加时,鱼油包埋率先增后减,POV值先减后增,在进/出口温度为140℃/70℃时有最高的包埋率和最低的POV值。通过分析确定最佳工艺参数如下,均质压力为40MPa,喷雾干燥进口温度为140℃,出口温度为70℃。在上述最适工艺条件下,鱼油微胶囊平均粒径为5.97μm,表面油含量为2.03%,微胶囊化包埋率为95.6%,在扫描电镜下观察微胶囊表面和内部结构良好,具有良好的包埋效果。     

喷雾干燥速溶红枣粉工艺优化及其冲调性分析

以红枣为原料,通过单因素试验探究喷雾干燥进风温度、雾化器转速、进料流量对速溶红枣粉的分散性、润湿性、水分含量及颗粒粒度的影响,确定进风温度、雾化器转速、进料流量3个因素为自变量,分散时间和润湿时间为响应值进行响应面优化试验。结果表明喷雾干燥制备速溶红枣粉的最优参数为:进风温度170℃、进料流量1.3 L/h、雾化器转速400 r/s,在此条件下测得润湿时间为3.86 s,分散时间为2.27 s,与模型预测值相符。     

Optimisation of a pilot‐scale spray drying process for probiotic yoghurt,using response surface methodology

The influence of drying air temperatures, drying air flow rate and feed flow rate on percentage survival rate (% SR) of starter and probiotic bacteria, moisture content, water activity and colour of probiotic yoghurt powder produced using a pilot‐scale spray dryer was investigated. Optimisation of spray drying conditions was achieved based on the desirability value. Results showed that inlet air temperature, drying air flow rate, feed flow rate and outlet air temperature of 150 °C, 478 m³/h, 2 L/h and 63.3 °C, respectively, were optimal conditions to produce powder that meets quality specifications and with a satisfactory% SR.     

A Critical Review on the Spray Drying of Fruit Extract: Effect of Additives on Physicochemical Properties

Spray drying accomplishes drying while particles are suspended in the air and is one method in the family of suspended particle processing systems, along with fluid-bed drying, flash drying, spray granulation, spray agglomeration, spray reaction, spray cooling, and spray absorption. This drying process is unique because it involves both particle formation and drying. The present paper reviews spray drying of fruit extracts, such as acai, acerola pomace, gac, mango, orange, cactus pear, opuntia stricta fruit, watermelon, and durian, and the effects of additives on physicochemical properties such as antioxidant activity, total carotenoid content, lycopene and β-carotene content, hygroscopy, moisture content, volatile retention, stickiness, color, solubility, glass transition temperature, bulk density, rehydration, caking, appearance under electron microscopy, and X-ray powder diffraction. The literature clearly demonstrates that the effect of additives and encapsulation play a vital role in determining the physicochemical properties of fruit extract powder. The technical difficulties in spray drying of fruit extracts can be overcome by modifying the spray dryer design. It also reveals that spray drying is a novel technology for converting fruit extract into powder form.     

淮山全粉喷雾干燥工艺优化研究

为了改善淮山全粉的喷雾干燥效果,优化喷雾干燥工艺,采用响应面法优化喷雾干燥条件,分析了不同进风温度、进料流量和固液比对产品品质的影响规律。结果表明:当进风温度为170℃,进料流量为15m L/min,固液比为1∶1.5,在此优化条件下得到的淮山粉水分含量为3.89%、吸水性为0.78g/g、溶解度为27.34%、堆积密度为0.87g/m L,产品综合评价得分最高,通过响应面优化得到的喷雾干燥工艺能有效应用于淮山全粉加工。     

不同干燥方式对复方赤灵芝提取物中5-羟甲基糠醛含量的影响

研究在干燥复方赤灵芝提取物时5-羟甲基糠醛的含量变化并探索合适干燥方案。该研究采用了喷雾干燥、真空干燥、红外线干燥、热泵干燥、热风干燥以及真空冷冻干燥对复方赤灵芝提取物进行处理,研究了不同工艺参数下5-HMF含量变化。喷雾干燥的进料速度、通气量逐渐增加时5-HMF含量先增加后减少;真空干燥下5-HMF含量随干燥温度、物料厚度的增加而增加,5-HMF含量、水分含量随真空度的增加而降低（P<0.05）;红外线、热泵及热风干燥下5-HMF含量随温度升高而增加。真空冷冻干燥后样品5-HMF含量为779.29 mg/kg,加工时间为50 h,耗时最长。在各优选方案下真空干燥所得样品5-HMF及水分含量最低为774.32 mg/kg、4.97%,加工时间17 h,耗时最短,样品呈黑褐色,质脆硬,不易复溶。因此,为保证有害物质5-HMF含量最低同时综合加工时间等因素,应优先考虑真空干燥方式,但还需采取进一步措施改善产品外观及复溶性。     

Density and Porosity in Drying Starch Materials

The particle density of granular and gelatinized corn starches was determined in the moisture range 0 to 1 kg water/kg dry solids, using a gas stereopycnometer. The bulk porosity (void fraction) of spherical starch samples at various moisture contents was estimated from the bulk and particle densities during air drying at 60°C. The particle density data fitted a polynomial function of moisture content (X), passing through a maximum value of 1500 kg/m³ at X = 0.15. The bulk porosity of the starch samples increased linearly during drying, reaching a value of 0.45 near dryness. Differences in structure between granular and gelatinized starches during drying were observed by stereomicroscopy. The changes in porosity could be related to variations of the effective moisture and thermal diffusivities of starch materials.     

Influence of process conditions on the physicochemical properties of açai (Euterpe oleraceae Mart.) powder produced by spray drying

The objective of this work was to study the influence of spray drying conditions on the physicochemical properties of açai powder. The process was carried out on a mini spray dryer and maltodextrin 10DE was used as carrier agent. Seventeen tests were made, according to a central composite design. Independent variables were: inlet air temperature (138–202 °C), feed flow rate (5–25 g/min) and maltodextrin concentration (10–30%). Moisture content, hygroscopicity, process yield and anthocyanin retention were analysed as responses. Powder moisture content and process yield were positively affected by inlet air temperature and negatively affected by feed flow rate, which are directly related to heat and mass transfer. Process yield was also negatively influenced by maltodextrin concentration, due to the increase on mixture viscosity. Powders hygroscopicity decreased with increasing maltodextrin concentration, decreasing temperature and increasing feed flow rate. Powders with lower moisture content were more hygroscopic, which is related to the greater water concentration gradient between the product and the surrounding air. Anthocyanin retention was only affected by temperature, due to its high sensitivity. In respect to morphology, the particles produced at higher temperature were larger and a great number of them showed smooth surface.     

Effect of spray‐drying parameters on the solubility and the bulk density of camel milk powder: A response surface methodology approach

Response surface methodology coupled with a Box–Behnken experimental design was used to investigate the effect of the air inlet drying temperature, the feed rate, and the fat content on the solubility and the bulk density of spray‐dried camel and cow milk powders. The response surface methodology analysis highlighted that milk fat content and feed rate were the most effective parameters affecting the solubility and the bulk density of cow and camel milk powders. Importantly, there was no significant interaction between the studied drying parameters and camel milk powder solubility or bulk density. Overall, camel milk powder exhibited a comparable solubility to that of cow milk powder with a higher bulk density.     

喷雾干燥工艺对胶束态酪蛋白结构及抗氧化性的影响

以脱脂牛乳为原料,采用超滤技术获得胶束态酪蛋白,研究进口温度130℃和150℃、雾化压力0.05 MPa和0.1 MPa喷雾干燥工艺下胶束态酪蛋白粉末的水分含量、粒径、堆积密度、表面形貌、溶解性、内源荧光特性以及抗氧化活性(还原力、Fe 2+螯合力、DPPH和ABTS自由基清除活力),并以冷冻干燥样品为对照。结果显示,随着喷雾干燥温度和雾化压力的升高,胶束态酪蛋白粉末的水分含量显著降低(P<0.05),堆积密度显著增大(P<0.05),粒径在150℃-0.1 MPa条件下最大,为(2.16±0.29)μm;冻干胶束酪蛋白的粒径最小,为(1.31±0.02)μm,堆积密度最大,为(416.47±3.94)mg/mL,水分含量与130℃-0.1 MPa和150℃-0.05 MPa下喷干样品差异不显著(P>0.05)。随着喷干温度和压力的升高,胶束态酪蛋白的溶解性和内源荧光强度呈现下降趋势,但最大发射波长和表面形貌不变。冻干样品的溶解性在pH 7时为(87.63±0.35)%,与130℃-0.05 MPa下的喷干样品差异不显著(P>0.05)。就抗氧化活性而言,130℃喷干时胶束态酪蛋白具有较好的还原力和ABTS自由基清除活力,150℃喷干时胶束态酪蛋白的DPPH自由基清除能力较好。进口温度150℃和雾化压力0.05 MPa工艺下胶束态酪蛋白的Fe 2+螯合能力最强。研究结论可为胶束态酪蛋白产业化开发及干燥工艺选择提供参考依据。     

High-oil-load encapsulation of medium-chain triglycerides and D-limonene mixture in modified starch by spray drying

Oil mixtures of medium-chain triglycerides (MCT) and D-limonene in mixing ratios from 10 to 100 wt% were encapsulated in modified starch (wall material) by spray drying to produce oil-rich powders. The oil load (mass ratio of oil mixture to wall material) of the infeed emulsion markedly influenced the properties of the infeed liquid and the characteristics of the resulting powder. The viscosity of the infeed liquid and the particle size of the powder exponentially decreased with increasing oil load, while the emulsion droplet size in the infeed liquid increased. In addition, retention of D-limonene during spray drying also decreased markedly with increasing oil load. Irrespective of the different oil loads and concentrations of the wall material, D-limonene retention was well correlated with the emulsion droplet diameter of the infeed liquid. The encapsulation efficiency of the oil mixture exhibited a maximum value (almost 100%) at an oil load between 0.5 and 1.0, before decreasing at higher oil loads. At an oil load of 2.0, the encapsulation efficiency of D-limonene was reduced to almost zero, while around 40% of the initial MCT was encapsulated in the powder. The increase in oil load also led to increased amounts of surface oil of MCT and D-limonene in the resulting powder due to the increasing emulsion droplet diameter of the infeed liquids. PRACTICAL APPLICATION: This study proposes the microencapsulation of medium-chain triglycerides under high-oil-load conditions by spray drying. The powders prepared by this process provide significant benefits in terms of rapid energy conversion after consumption without accumulation in the body. Important quality factors of the powder products such as the encapsulation efficiency and the amount of surface oil were examined to understand the optimum process conditions for spray drying.     

雨生红球藻喷雾干燥工艺的建立与放大

为了建立具有应用价值的雨生红球藻喷雾干燥工艺,本文使用采收后的雨生红球藻藻泥为原料,进行中试(蒸发能力25 kg·h?1)和生产规模(蒸发能力250 kg·h?1)实验,建立并放大了雨生红球藻的喷雾干燥工艺.结果表明,在中试规模下,进风温度在130～180℃范围内对藻粉理化指标没有显著的影响;出风温度在50～75℃范围...