The Application of Ultrasound Pretreatment and Pulse-Spouted Bed Microwave Freeze Drying to Produce Desalted Duck Egg White Powders

Fresh duck egg white (FDEW) powders and desalted duck egg white (DDEW) powders were produced by using a novel pulse-spouted bed microwave freeze dryer and a conventional freeze dryer. The desalting process of the salted egg white was carried out in the presence or absence of ultrasound pretreatment. The drying time, microstructure, apparent density, color, and functional properties (gelling, foaming, and emulsifying) of FDEW and DDEW powders obtained from both the pulse-spouted bed microwave freeze-drying (PSMFD) and a conventional freeze-drying (CFD) were studied in order to evaluate the physicochemical and functional properties of these powders. The results show that PSMFD produced FDEW powders with better color appeal (higher L^* and lower b^*), lower apparent density, as well as shorter drying time compared to the FDEW powders produced by the CFD. FDEW powders produced from PSMFD produced more transparent gels, emulsions with higher foam stability, and higher emulsifying activity index compared to the FDEW powders obtained from CFD. Regarding the powders obtained from DDEW by using PSMFD, the ultrasound pretreatment during the desalting process produced DDEW powders with higher gel strength, higher foaming capacity, higher foam stability, higher emulsion stability index, as well as shorter drying time compared to the DDEW powders in which ultrasound treatment was not carried out during the desalting process in the upstream.     

十二烷基胍盐酸盐的合成与性能

以氰胺和十二烷基伯胺为原料,一步合成了十二烷基胍盐酸盐表面活性剂,经单因素实验确定了较佳工艺条件为:体积分数95%乙醇为溶剂,n(十二胺):n(氰胺):n(盐酸)=1:1.5:1.1,反应时间2 h。产品通过IR、1HNMR和元素分析进行了结构表征,并对其表面活性、泡沫性、乳化性和抑菌性进行了测试。结果表明,十二烷基胍盐酸盐的CMC为5.5 mmol/L,最低表面张力为24.1 mN/m,与DTAC相比,具有较好的泡沫性能,较差的乳化能力,较强的抑菌活性,在25 mg/L质量浓度下对金黄色葡萄球菌和大肠埃希氏菌的抑菌率达100%,在100 mg/L质量浓度下对白色念珠菌的抑菌率达99.5%。     

Functional properties of a protein product from Caryodendron orinocense (Barinas nut)

The functional properties of Caryodendron orinocense protein product were investigated and compared with those of soybean (Glycina maxima). The product protein content was 24.47 g/100 g (Nx6.25). Solubility increased at both sides of the isoelectric point (pH 4.0) and with increased NaCl concentration up to 0.5M. Compared with soybean flour (50% protein), the protein product exhibited higher water and oil absorption, but lower emulsifying activity, emulsion stability, foaming capacity, and foam stability, the last one increase at higher pH. Emulsifying activity, foaming capacity, and foam stability were ionic strength dependent. C. orinocense protein product increased its emulsifying activity steadily from 0.05M to 0.75M NaCl, while it remained almost constant for soybean flour. Foaming capacity increased drastically at pH 10. The minimum time and concentration to form a gel was 20% in 4 min and 10% in 8 min for the Caryodendron protein product and soybean flour, respectively. The bulk density was 0.5056+/-0.0041 g/mL.     

Ultrasonication as pretreatment for drying of tomato slices in a hot air–microwave hybrid oven

This study aims to investigate the effect of ultrasonic pretreatment on drying time and quality properties of tomato slices dried by microwave combined with hot air at 60°C. The influence of ultrasound pretreatment (0, 20, and 40?min) and microwave power (120, 150, and 180?W) on drying time, color, total phenolic content, lycopene, vitamin C, and rehydration capacity of dried slices of tomato was studied. Results showed that as the microwave power level increased, drying time decreased significantly (about 46.4%). Ultrasound pretreatment decreased the drying time by 7.38% only at 120?W microwave power and 40?min of pretreatment compared to those without ultrasound pretreatment at the same microwave power. Depending on drying conditions, vitamin C and lycopene contents reduced from 433.94 to 81.89?mg AA/100?g dry solids and 3920.57 to 415.40?mg/100?g dry solids, respectively. The change in total phenolic content was not severe as much as vitamin C contents. Rehydration capacity of pretreated samples was larger than nontreated samples. The color values of dried tomato slices were in the acceptable range. Both microwave power and ultrasound pretreatment affected the quality of the final product significantly.     

烷基磷酸酯盐表面性能的研究

合成了烷基磷酸酯盐混合物及高纯度的单、双酯盐,并将单、双酯盐混合得到特定的混合物;研究并比较了各种磷酸酯盐的表面张力、润湿、起泡及乳化性能。结果表明,用P2O5合成的磷酸酯表面性能最好,单酯也有良好的表面性能。在纯的单酯、双酯中加入少量脂肪醇,有利于提高起泡及乳化性能;纯的单酯润湿性能较好。     

INFLUENCE OF ENZYMATIC HYDROLYSIS ON THE FUNCTIONAL PROPERTIES OF SESAME CAKE PROTEIN

This study investigated the effect of enzymatic hydrolysis on the functional properties of sesame cake protein. Protein hydrolyzates from sesame cake protein were obtained by enzymatic hydrolysis using Alcalase at 50°C and pH 8.5. Water-holding capacity, oil-holding capacity, foam capacity and stability, and emulsifying activity and stability of the hydrolyzates were determined. All protein hydrolyzates showed better functional properties than the original protein. Foaming and emulsifying stability decreased as the degree of hydrolysis increased. The water-holding capacity, foaming activity, and emulsifying activity of the hydrolyzates increased with the increase in levels of hydrolysis. Enzymatic modification was responsible for the changes in protein functionality. These improved functional properties make sesame cake protein hydrolyzates a useful product in foods such as bread, cake, ice cream, meat products, desserts, and salad dressing.     

Response surface methodology (RSM) as relevant way to study and optimize texturing by instant controlled pressure drop DIC in innovative manufacturing of egg white and yolk powders

This study aimed to use the Instant Controlled Pressure Drop as a texturing pretreatment prior to air flow drying as a new way for the manufacturing of egg white and yolk powders evaluating the impact of DIC operating parameters; the saturated steam pressure and processing time, on the physical and functional properties of the end products. The obtained results showed that the DIC-textured egg white and yolk powders had high quality attributes compared to those obtained from classical air flow drying. Moreover, it was better than freeze dried powders in terms of water absorption capacity, emulsifying capacity, and foaming capacity and stability.     

A Combination of Freeze Drying and Microwave Vacuum Drying of Duck Egg White Protein Powders

High energy consumption during freeze drying (FD) is a major concern that limits its application on common food product manufacturing. In this research, fresh duck egg white protein (FDEWP) powder and desalted duck egg white protein (DDEWP) powder were obtained by a combined two-stage tandem drying technologies (FD and microwave–vacuum drying [MVD]) in order to reduce energy consumption while maintaining good product quality. The results showed that the drying time for the FDEWP and DDEWP powders was significantly decreased by FD + MVD compared to those obtained by the FD-only process. The FDEWP powders dried by FD + MVD had a better color (higher L* and lower b*), lower apparent density, and lower foaming stability but higher emulsifying index than those dried by FD only. The DDEWP powder dried by FD + MVD had a product quality similar to that of FDEWP powder, suggesting that the DDEWP powder could be widely used as a food ingredient.     

Synthesis and Properties of Dodecyldiethoxylamine Oxide

Dodecyldiethoxylamine oxide (DDEAO) was synthesized by the reaction of dodecyldiethoxylamine with hydrogen peroxide in water as the solvent. Surface activity, wetting ability and emulsifying capacity were investigated and compared with that of dodecyldimethylamine oxide (DDMAO). Results indicate that the critical micelle concentration (CMC) of DDEAO is lower than that of DDMAO, while its surface tension at CMC (γ_CMC) is slightly higher. The wetting ability of DDEAO is similar to that of DDMAO. For its capacity of emulsifying liquid paraffin, DDEAO is found to be better than DDMAO, but it is the opposite for emulsifying soybean oil. The foaming properties and thickening function of DDEAO in mixtures with alcohol ether sulfate and alkylbenzene sulfonate were also studied. As expected, complex surfactant systems exhibit good foaming ability and DDEAO exhibits a good thickening function.     

超声波处理对麦胚清蛋白结构和功能性质的影响

研究了超声波功率和处理时间对麦胚清蛋白的紫外光谱、荧光光谱、表面疏水性、溶解度、起泡性能、乳化性能的影响. 结果表明,超声波处理对麦胚清蛋白的紫外和荧光光谱有明显的影响,其溶解度在超声波功率1800 W时最高,比对照组提高了96.2%;在600 W的表面疏水性和乳化性、900 W的起泡性和起泡稳定性最高,分别比对照组提高了16.8%, 12.5%, 18.8%和6.0%;处理时间为20 min时的溶解度及10 min时的表面疏水性、起泡性、起泡稳定性、乳化性达到最大,分别比对照组提高了101.3%, 22.1%, 15.0%, 21.9%和12.7%. 但超声波处理降低了麦胚清蛋白的乳化稳定性.     

高回收率反渗透海水淡化工艺

目前反渗透海水淡化的回收率小于40％。本文研究开发死端超滤预处理技术和反渗透一纳滤联合脱盐相结合的膜集成海水淡化新工艺,与传统工艺比较,具有装置体积小,产水回收率高等优点。文章介绍了采用新工艺的海水淡化装置样机的试制情况及现场运行结果。沿岸海水为料液,操作压力1为5．1MPa条件下,操作压力2为2.0MPa条件下,装置脱盐率99．21％,产水量3971.3L/h,产水回收率55％。海水淡化装置对海水中Ca^2 、Mg^2 、Na^ 、HCO3^-、Cl^-、SO4^2-、TDS,总碱度,总硬度的脱除率分别为99％,99．6％,99．21％,95％,99．35％,98．48％,99.21％,95％,99．42％。     

高回收率反渗透-纳滤海水淡化成本

采用文献[8]提出的代表性费用概念，在相同淡水产量(8．95m^3／d)条件下，讨论了反渗透一纳滤海水淡化工艺产水成本，并与传统一级反渗透海水淡化工艺的产水成本进行了比较，结果表明：新工艺(回收率60％)的总设备直接投资费分别比回收率为20％和40％时的传统工艺下降20．06％和6．27％．其中，预处理设备投资费分别下降43．41％和19％；操作费用中的能源费分别下降13．33％和7．14％．     

Functional and nutritional properties of modified proteins of sesame (Sesamum indicum, L.)

A study on the functional and nutritional properties of sesame (Sesamum indicum, L.) flour, concentrate and enzymatic hydrolysates, demonstrated that nitrogen solubility of the hydrolysates is improved, in water (85%) and at different pHs (91-95%), by the action of neutrasa 0.5L and alcalasa 0.6L, yielding a product with good emulsifying and improved foaming properties. Hydrolysates produced by the pH-stat method, then freeze-dried and spray-dried presented a PER of 1.1 and 0.9, respectively. The flour and the concentrate had PER values of 1.2. Supplementation of one of the hydrolysates with soya hydrolysate (1:1), improved the PER to a value similar to that of casein. Use of neutrasa 0.5L and alcalasa 0.6L enzymes, enhances the sesame protein solubility without modifying extensively the PER. Besides, it yields a dehydrated product with improved emulsifying and foaming properties.     

Functional properties of hydrothermally cooked soy protein products

The effects of hydrothermal cooking on the functional properties of defatted soy flour, aqueous alcohol washed soy protein concentrate, and soy protein isolate were determined in samples that were treated at 154°C by infusing steam under pressure for 11, 19, 30, and 42 s, and then spray dried. Hydrothermal cooking increased the nitrogen solubility index (NSI) of the concentrate from 15 to 56% and altered the solubility profile from a flat profile to one more typical of native soy protein. Hydrothermal cooking also improved foaming and emulsifying properties of the concentrate. For isolate, hydrothermal cooking also improved NSI and foaming and emulsifying properties, although the improvements were less dramatic than with concentrate. NSI and emulsifying properties of the flour were improved by some processing conditions, but foaming properties were not improved by hydrothermal cooking. Dramatically increased protein solubility of concentrate and modestly improved protein solubilities of flour and isolate by hydrothermal cooking, which will also inactivate trypsin inhibitors and microorganisms, have considerable practical significance to protein ingredient manufacturers and those who use these ingredients in foods and industrial products.     

In situ ultrasound enhancement of octanoic acid directional solvent extraction for seawater desalination

The low yield and high salinity of the water product have limited the use of directional solvent extraction desalination method to the treatment of only low salinity water. In this research, in situ ultrasound enhancement of octanoic acid solvent extraction desalination is reported. The pre-prepared 3.5% (w/w) of saltwater solution and octanoic acid were mixed at five different temperatures which resulted in two phases. The performance of extraction for each set was evaluated based on salinity, yield of the recovered water, and solvent residual in the product water. The calculated yield of pure water under the ultrasound effects was higher than that without the ultrasound. This is due to the role of ultrasound in weakening the intermolecular interaction to dissociate water from salt, increasing the solvent efficiency in extracting water. The recovered water salinity was lower by using the ultrasound which can be explained as result of increasing the water yield.     

Effects of Ultrasound and Microwave Pretreatments of Apple Before Spouted Bed Drying on Rate of Dehydration and Physical Properties

Pretreatments of fruits before drying have been proposed as alternative way to improve the quality of dried fruits and reduce drying time. In the present study, the effects of different pretreatments (ultrasound and microwave) on apple cubes prior to spouted bed drying were investigated. Ultrasound pretreatment resulted in a great loss of sugars (25.7% for 15 min) compared to microwave pretreatment, where little rise in sugar content was observed (1.6% at 300 W). Ultrasound pretreatment improved the drying rate more than microwave pretreatment. Nevertheless, microwave-pretreated dried apples were harder and had lower water activity than ultrasound-pretreated ones. Low-frequency nuclear magnetic resonance (LF-NMR) analysis was used to study the water state and revealed that all pretreatments promoted redistribution of water among apple cell compartments and showed that most of the water lost was from the vacuoles. If dried low-calorie fruits are required then ultrasound pretreatment would be preferred.     

脂肪醇聚氧乙烯醚磺酸盐的合成及表面、乳化和泡沫性能研究

以脂肪醇聚氧乙烯醚（3）（AEO-3）为原料、以甲苯为溶剂,首先与金属钠反应生成醇钠,再与2-氯乙基磺酸钠进行Williamson反应合成脂肪醇聚氧乙烯醚（3）磺酸钠（AESO）。经两相滴定法测定,AESO的产率达80％。经红外光谱表征,纯化后产物与目标化合物的分子结构完全相符,为十二醇聚氧乙烯醚（3）磺酸盐。对产物的表面、乳化和泡沫性能进行测试,结果表明AESO比传统的脂肪醇聚氧乙烯醚硫酸盐（AES）有更好的表面活性,其最佳的乳化浓度为0．002g·L-1、最佳起泡浓度为1490mg·L-1。     

Improvement of grinding characteristics of Indian coal by microwave pre-treatment

The influence of microwave pretreatment on the grindability of high-ash Indian coal was investigated. Scanning electron microscope analysis characterized the micro fractures in microwave treated coal samples, which may be due to the thermal stress cracking resulting from the microwave pretreatment. X-ray diffraction analysis showed that the microwave treated coal had a higher peak compared to the untreated coal indicates that the crystallinity increased with the microwave exposure time. The calculation of the Hardgrove grindability index indicated an increase in the ease of grinding or an increase in the grindability index of the microwave treated coal. Bond grindability tests showed that the work index decreased 15.4% after a microwave exposure time of 120 s. Grindability tests showed that the microwave treated coal ground much more rapidly initially than the untreated coal, with the specific rate of breakage (S₁) increasing by an average of 15%. The results showed that the rates of breakage of both microwave untreated and treated coal samples were dependent on particle size.     

Effect of canola meal fermentation and protein extraction method on the functional properties of resulting protein products

The present study investigated the effect of solid-state fermentation (SSF) of cold-pressed (CP) and hexane-extracted (HE) canola meals with Aspergillus niger NRRL 334 and Aspergillus oryzae NRRL 5590 on the functionalities of protein products extracted from them. After SSF, proteins were recovered using alkaline extraction-isoelectric precipitation (AE-IP) or salt extraction-dialysis (SE). SSF of the two meal types reduced the protein content of the extracts produced by AE-IP. There were varied effects to solubility, foaming, and emulsifying properties as a result of SSF under the combined influence of functionality pH, strain, meal type, and protein extraction method. The protein isolate produced from CP meal using SE had increased solubility at pH 7 (from 51.8% to 90.7%) when the meal was fermented with A. oryzae. Both strains resulted in an over twofold increase in the emulsifying activity index (at pH 7) of AE-IP products from CP meal. For both protein extraction methods, the protein products from A. niger fermented HE meal had better foaming capacity (FC) at pH 7 than the controls (non-fermented), but reduced FC at pH 3. Overall, regardless of meal fermentation, the SE products were richer in protein and had higher oil holding capacity (OHC), whereas the water holding capacity (WHC) was higher for AE-IP isolates. SSF of the meals generally improved the O/WHC of the extracted proteins. The findings suggest that canola protein functionality could be effectively modulated by SSF with different microbial strains under various processing conditions to enhance their applicability in the food industry.     

N-油酸酰基丝氨酸表面活性剂的合成与性能

采用两步法合成了N-油酸酰基丝氨酸。优化的合成工艺条件为:n(油酸酰氯)/n(丝氨酸)=1.2,反应温度控制在45℃~50℃,反应时间4 h,pH=12,产率为87.8%。利用IR、元素分析和1HNMR对产物结构进行了表征。测定了所得产物的表面活性和应用性能。结果表明,通过在丝氨酸中引入油酸酰基后,其最低表面张力为27.6 mN/m;乳化能力、乳化稳定性可达85%以上;泡沫高度在180 mm~189 mm;平均润湿时间为65 s;10 d内生物降解度达到96.0%以上。