Effect of cooking processes on tilapia aroma and potential umami perception

Tilapia is a freshwater fish group with a sustainable prospect but suffers off-notes appearing during cooking processes.To promote pleasant odorants by thermal cooking processes,tilapia fillets were cooked in different ways(roasting,microwave-heating,boiling and steaming).Their aroma profiles were analysed with special focus on off-notes and umami-enhancing odorants by principal component analysis,and correlated with the heating time,colour,moisture and water activity by partial least squares regression analysis.Results showed that the“green”and“earthy”off-notes were highly correlated with the boiling process(excess of water,short heating time),while most of the umami-enhancing odorants had a high association with the roasting process(low water content,long heating time,better Maillard reaction).This study indicated that roasting is the most adapted cooking process promoting Maillard-derived aromas,umami-enhancing aromas and meanwhile,reducing off-notes.This research helps in understanding the off-note generation in tilapia and promoting desirable umami-enhancing odorants.

A value-added cooking process to improve the quality of soybean:Protecting its isoflavones and antioxidant activity

This study investigated the effects of domestic cooking process on the variations of soybean isoflavones,aiming at understanding the conversion of-glucosides and aglycones isoflavones during the process and the relation with antioxidant activity.It was found that-glucosides isoflavones was significantly increased from 223.01(raw)to 727.29 mg/g(frying at 160◦C for 2 min),but boiling showed only a slight increase to 258.14 mg/g.The process for the mixed cooking of soybeans with vegetables was also evaluated,which is quite common in home cuisine.The results showed all bioactive ingredients were aggressively destroyed by over processing,but interestingly,green pepper and kelp exhibited isoflavones generation potentials for soybean.In addition,cooking from 60 to 160◦C for 2 or 5 min,showed a significantly decrease on FRAP.However,in the case of fried soybeans which treated at 120◦C or 160◦C,when extending the heating time to 5 min,their FRAP activity got a significant increase.The present study may provide a practical guidance for healthy soybean cooking,by using frying around 120◦C for 5 min and mixed with some vegetables such as green peppers or kelp.

AN APPROACH TO THE STRUCTURE AND PROCESS OF THE V TYPE COCOON—COOKING MACHINE WITH 84 STEAMERS

This paper Introduces the strueture and the main character of the V typecocoon-cooking machine with 84 steamers and analyses its main function in thefield of the process of cooking cocoon.Many productive experiments have provedthat its process is feasible,its structure,reasonable and obvious economicaleffects can be brought out by using the

Changes during Cooking Processes in 6 Varieties of Andean Potatoes (<i>Solanum tuberosum</i>ssp. Andinum)

The value of the native potato varieties grown in Argentinean northwest lies both in their fundamental role as a source of food for the population and in their potential for the development of new products. The aim of this work was to study the changes produced by two common cooking processes (boiling and frying) on the nutritional, textural and functional characteristics of five Andean potatoes varieties. The cooking process (boiling) does not significantly affect the composition of potatoes, but there are losses of vitamin C;a greater loss was observed when they were boiled shelled. In frying potatoes vitamin C is completely destroyed. Resistant starch values between 0.90 and 4.58 g/100g of potato were found for raw Andean varieties;they decreased during the cooking process (boiled) (0.15 to 0.54 g/100g of potato) and increased again to be stored for 48 h at 4&degC (0.73 - 1.88 g/100g of potato). The frying process produced an increment in energy value between 92% and 148% according to variety. Regarding to the fracture strength and hardness, no significant differences were observed between the Andean varieties and the control (Spunta) at the initial or final stages, but there were differences during the intermediate stages.

Process Control for Dissolving Pulp by SuperBatch Cooking

The process of producing dissolving pulp with SuperBatch cooking was introduced. The factors that affected the quality of the dissolving pulp and the corresponding operations were investigated.

激光冲击Johnson-Cook模型材料参数优化

采用Abaqus有限元软件,建立激光冲击718镍铬合金诱发的残余应力场非线性弹塑性有限元模型,实现激光冲击强化残余应力场的数值仿真.通过仿真分析及试验结果对照,说明以Johnson-Cook模型作为本构关系是可行的,激光冲击能形成残余压应力层,提高疲劳寿命,但由于应变率的差异,必须对JC模型材料参数进行优化,才能取得较精确的结果,并从激光功率密度对残余应力场的分析进一步加以验证.结果表明,提出的JC模型材料参数优化方法简单易行.

基于Johnson-Cook模型的不锈钢管剪切数值模拟

剪切是乏燃料后处理工艺流程关键环节,因受强辐照制约,对该剪切工艺研究很少,剪切工艺参数需通过大量试验进行设计优化,成本高、周期长且无法掌握剪切机理。以乏燃料组件主要支承结构不锈钢管为研究对象,采用基于Johnson-Cook模型的有限元数值模拟方法来分析剪切过程。设计剪切试验验证上述模型的正确性,并研究剪切间隙、刀具角度、刀具棱边宽度等工艺参数对剪切的影响。结果表明:剪切试验与模型结果拟合性很好,证明了该模型的正确性;最大剪切力、断裂时剪切力随剪切间隙、棱边宽的增大而增大,随刀具角度增大而减小;剪切间隙对压紧段断口形貌影响较大,刀具角度和棱边宽对分离段开口高度影响较大。

基于等温压缩试验的20Cr2Ni4A钢Johnson-Cook本构模型及热加工图

采用Gleeble-3500热模拟试验机在变形温度700~1000℃、应变速率0.001~1 s^-1条件下进行了20Cr2Ni4A钢的等温压缩试验。结果表明,20Cr2Ni4A钢的流动应力随变形温度的降低或应变速率的增加而增加,其在700℃变形条件下的真实应力-应变曲线的变化规律异于其它变形温度,真实应力达到峰值后,以软化机制为主,但并未出现先强化后软化的单峰型应力-应变曲线。构建了20Cr2Ni4A钢的Johnson-Cook本构模型,并对应变速率敏感系数进行了修正,修正后的本构模型的适用范围为变形温度700~1000℃、应变速率0.001~0.1 s^-1。通过对热加工图的分析,确定的20Cr2Ni4A钢合理的热加工参数范围为:变形温度925~1000℃、应变速率0.001~0.05 s^-1。本研究可为20Cr2Ni4A钢热加工工艺参数的选择提供理论依据。

COOK宫颈球囊扩张器用于高危妊娠促宫颈成熟的效果观察

目的:观察COOK宫颈球囊扩张器用于高危妊娠促宫颈成熟的效果。方法:选择100例足月高危妊娠初产妇,按随机数字表分为观察组与对照组,各50例。观察组使用COOK宫颈球囊扩张器,对照组使用缩宫素。比较两组干预前后的宫颈Bishop评分、促宫颈成熟率、第一产程、第二产程、总产程、产后24 h出血量、住院时间、引产成功率、阴道分娩率、宫颈裂伤、阴道血肿、产后出血发生率、新生儿体质量、Apgar评分、新生儿窒息率与窘迫率。结果:干预后观察组的宫颈Bishop评分高于干预前与对照组(P<0.05)。观察组促宫颈成熟率为76.00%,高于对照组(P<0.05)。观察组第一产程与总产程均短于对照组(P<0.05),产后24 h出血量与住院时间更低(P<0.05)。观察组引产成功率与阴道分娩率为74.00%、70.00%,均高于对照组(P<0.05),两组新生儿体质量、Apgar评分、宫颈裂伤、阴道血肿、新生儿窘迫、新生儿窒息发生率的差异均无统计学意义(P>0.05)。结论:COOK球囊宫颈扩张器在高危妊娠产妇中的应用可有效促宫颈成熟并扩张宫颈,缩短产程、减少出血并提高阴道分娩率,且不会增加宫颈裂伤、阴道血肿、新生儿窘迫与窒息,操作简单、安全有效,值得临床推广。

Global production, processing and utilization of lentil： A review

Lentil is a highly nutritious legume with an ample quantity of carbohydrates and good amount of proteins, minerals, vitamins, phytochemicals and fibres. Although it has been used as staple food since ancient times, its usage has been limited in developed countries, especially due to the lower protein digestibility, presence of anti-nutritional factors, flatulence and poor cooking qualities. Processing of lentils including dehulling and splitting and isolation of major fractions, e.g., proteins and starches are some of the strategies that can be adopted to add value and increase consumption of these legumes. This review paper intends to provide detailed overview of lentil＇s global production, nutritional composition and processing methods of lentil. Methods of isolation/characterization of lentil protein and starch and their subsequent application in foods are also presented.

藜麦挤压面条加工工艺优化

以藜麦为原料,采用双螺杆挤压技术制备藜麦面条。以蒸煮特性和质构特性为考察指标,在单因素试验的基础上,应用响应面法优化挤压藜麦面条的挤压工艺参数,探究挤压温度、物料水分含量和螺杆转速对面条品质的影响。结果表明,挤压藜麦面条的最佳工艺条件为挤压温度113℃、物料水分含量45%、螺杆转速80r/min,此时面条的蒸煮损失较低,硬度较高。

关于不同烹调方法对食品营养素的影响探讨

本文探讨了不同烹调方法对食品营养素的影响,强调了食品营养价值对健康的重要性,提出了保留食物营养素的措施,旨在帮助人们选择更加健康的烹调方法。

真空低温烹调技术对肉制品品质的影响研究进展

真空低温烹调(Sous vide)是在真空条件下进行的一种经严格控制温度和时间的烹调技术。与传统的烹调方法相比,真空低温烹调因能有效减少产品中营养成分的损失,保留食品的原有风味,改善肉制品嫩度等优势而受到大众关注,近几年被广泛研究并应用于肉制品加工。本文主要综述了真空低温烹调技术加工条件和方式的改变对肉制品食用品质的影响,指出适宜的加热温度和时间能提高肉制品风味和嫩度、促进营养物质的保留,且低温长时间加热有助于提高肉类的安全性。同时本文还阐述了真空低温烹调与其他技术联用对产品嫩度和安全性的显著影响,为更好地促进真空低温烹调技术在肉制品精深加工中的应用和实现真空低温烹饪肉制品的工业化生产提供了理论依据。

熟化工艺对脊尾白虾品质的影响

为了优化脊尾白虾(Exopalaemon carinicauda,E.carinicauda)的熟化工艺,避免不合适的熟化工艺带来的产品品质劣变与能源浪费,探究了85、90、95℃水煮处理和蒸汽蒸制的熟化工艺对脊尾白虾品质的影响。在测定传热曲线的基础上,以菌落总数、多酚氧化酶(polyphenol oxidase,PPO)相对酶活力、蒸煮损失率、持水力、粗蛋白质质量分数、质构特性和色泽为指标,进行综合评价。结果表明:蒸制处理1 min时PPO已基本失活,菌落总数降至可食用标准内;与相同时间下其他处理组相比,该组的蛋白质质量分数更高,弹性、内聚性和咀嚼性更好,色泽更红;但其持水力更低,水分损失更多,如果是虾熟化后继续加工成虾干制品,则干燥前较低的水分质量分数有利于干燥环节的进行。综上,蒸汽蒸制1 min是脊尾白虾的最适熟化工艺。

响应面法优化新疆椒麻鸡腿煮制工艺

为开发出新疆椒麻鸡腿休闲食品,该研究以三黄鸡鸡腿为原料,以出品率、质构分析和感官评分为主要评价指标,通过单因素试验和响应面试验优化鸡腿的煮制工艺。结果表明,椒麻鸡腿的最佳煮制工艺参数为煮制时间26 min、煮制温度90℃、食盐添加量3.00%(以肉质量计),在此条件下制作的椒麻鸡腿的感官评分为88.30分,接近理论值。以该研究研发出的煮制工艺煮制的椒麻鸡腿有嚼劲,椒麻鲜香,咸淡适中,无异味,可为新疆椒麻鸡腿的开发应用提供一定的科学依据。

Changes in wheat starch grains using different cooking methods: Insights into ancient food processing techniques

We investigate the morphological changes in starch grains from wheat(Triticum aestivum) using different cooking methods(boiling, steaming, frying, and baking). We compare the cooked starch grains with starch grains from ancient wheat flour cakes(Astana Cemetery, Turpan Basin, Xinjiang, China) to determine the cooking techniques used by people in Xinjiang 1200 years ago. Heat and water content affect starch grains when different cooking methods are used. Boiling and steaming results in the collapse of wheat starch grains accompanied by extreme swelling, curved granules, pasting, almost full gelatinization, a distinct extinction cross and vague granule outlines. Frying and baking cause less swelling, fewer curved granules, less pasting and only partial gelatinization of wheat starch grains, but the extinction lines are still distinct and the outlines of granules relatively clear. The pale brown substances on the starch grains make starch from baked-wheat products distinct from those cooked using other methods.

清洗及烹饪对芥菜和普通白菜中残留虫螨腈和高效氯氰菊酯膳食暴露风险的影响

为明确不同清洗和烹饪方式对芥菜和普通白菜中残留2种脂溶性农药(虫螨腈和高效氯氰菊酯)膳食暴露风险的影响,模拟厨房常用5种清洗方式(食用盐水、食用小苏打水、淘米水、自来水、食用醋水溶液)分别清洗芥菜和普通白菜,以及4种烹饪方式(煮、蒸、炒、腌制)烹饪加工后,利用QuEChERS样品前处理及气相色谱-串联质谱(GC-MS/MS)、超高效液相色谱-串联质谱(UPLC-MS/MS)方法检测样品加工前后虫螨腈和高效氯氰菊酯的残留量变化,计算加工因子,并根据我国3个代表性人群(儿童、育龄妇女、一般人群)的膳食数据,估算加工前后农药膳食暴露量变化以及对长期膳食暴露风险的贡献率(ADIi%)和短期膳食暴露风险(%ARfD)的影响,评价了清洗和烹饪加工过程对减少农药残留膳食暴露风险以及降低膳食暴露风险评估不确定性的作用。结果表明:芥菜采用食用小苏打水清洗,普通白菜采用食用盐水清洗,对2种农药残留的去除效果最好,显著优于自来水清洗;经过清洗、烹饪后,其加工因子(PFTotal)在芥菜中介于0.06~0.24(虫螨腈)和0.04~0.11(高效氯氰菊酯)之间,在普通白菜中介于0.05~0.21(虫螨腈)和0.06~0.11(高效氯氰菊酯)之间,清洗及烹饪加工使得2种农药的估算暴露风险值降低了76%~96%。研究表明,日常厨房加工可不同程度降低虫螨腈和高效氯氰菊酯残留对我国代表性人群的长期及短期膳食暴露风险,针对芥菜和普通白菜而言,厨房加工可使高效氯氰菊酯残留的%ARfD<100%,但不能使虫螨腈残留的%ARfD<100%。

熟制程度和油炸工艺对冻熟草鱼块品质的影响

【目的】解决预制烤鱼等冻熟鱼制品复热后口感和品质下降的问题。【方法】选取草鱼(Ctenopharyngodon idella)为研究对象,经油炸-冷冻-复热3种不同工序处理,以水分含量、肌原纤维小片化指数、剪切力、脂肪氧化程度、微观结构、蛋白质二级结构和色差等为指标,探究熟制程度对冻熟草鱼块品质的影响。在此基础上,以水分含量、肌原纤维小片化指数及色差为指标,探究不同油炸温度(160、180、200℃)对达到相同成熟度的冻熟草鱼块品质的影响。【结果】随着熟制程度增加,草鱼块的水分含量和持水性呈逐渐降低的趋势,不易流动水逐渐转变为自由水。冻融2次后,不同熟制程度的草鱼块的剪切力均较冷冻前降低。其中,中心温度为75℃的草鱼块的剪切力值和肌原纤维小片化指数分别是中心温度为45℃的草鱼块的1.33倍和1.22倍,肌原纤维结构损伤程度严重,鱼肉嫩度较差。同时,冻融处理降低了蛋白质α-螺旋和β-折叠的相对含量,蛋白质无序化程度增加。冻融2次复热后,中心温度为45℃草鱼块的持水性、剪切力、脂肪氧化程度、微观结构、感官评分等均优于中心温度为60和75℃的草鱼块。同时,研究发现采用200℃进行高温短时油炸的冻熟草鱼块的水分含量和肌原纤维小片化指数均较优,且草鱼块表面呈金黄色泽。【结论】200℃油炸草鱼块至中心温度为45℃,不仅可以改善冻熟草鱼块的色泽,也可以有效提升冷冻熟鱼肉复热后的品质。【意义】研究获得的熟制程度和油炸工艺条件,能够显著提高冷冻熟制鱼肉产品复热后的口感,为鱼类预制菜的开发、品质改善及大宗养殖鱼类的加工利用提供指导。

Expert perspective on technological choice for cooking energy transition in Nepal

Solid biomass dominates as the primary source of cooking energy,especially in rural households of Nepal.The use of solid biomass has a detrimental effect on health,exacerbates the burden of biomass collection,and hampers access to clean energy.Understanding the factors influencing the choice of modern cooking fuels is crucial to improving energy security and resilience and easing the transition to clean fuels.This study evaluates technological choices for the transition in cooking energy from the perspective of experts working in the government,non-government,and academia sectors.A structured questionnaire survey was prepared with five criteria and nine cooking technology options.Fifty-one experts responded to the survey,and their responses were analyzed using the analytical hierarchy process.The study reveals that efficiency and capital cost are the primary criteria for selecting cooking technology.The most suitable clean cooking technology is an induction stove followed by a hot plate,while the least preferred technology is a Bayupankhi stove followed by two-pothole mud improved cooking stoves.To ensure the robustness of the method,sensitivity analysis was performed on the two primary criteria efficiency and capital cost of the cooking technology.The analysis revealed robust and consistent rankings of technologies.This study should help create a conducive environment for relevant stakeholders and policymakers to formulate and implement relevant policies and strategies to accelerate the cooking energy transition in Nepal.

食用油脂热烹饪油烟组分特征、健康风险及其影响因素的研究进展

热烹饪是中式烹饪中食用油最主要的应用场景之一。食用油在加热烹饪过程中产生的烹饪油烟,是由多种有机物和固体颗粒物等组成的复杂固液气成分,对室内空气和人体健康产生不良影响。本文首先综述了食用油脂烹饪油烟中两大类主要危害物,即颗粒物和挥发性气体成分的组分特征,及其在油脂热烹饪过程中的排放情况,并进一步总结了热烹饪油烟暴露程度对人群呼吸系统疾病和其他健康风险的影响;其次,从热烹饪方式、烹饪食材种类和食用油品质和基本性质的角度,探讨了食用油热烹饪油烟的主要影响因素;最后,对基于食用油热烹饪油烟气组分特征优化油脂加工技术,开拓未来油脂加工新工艺、新材料、新途径,实现食用油脂精准适度加工和绿色低耗加工,制造高品质营养健康中式烹饪食用油进行了展望。本文将为未来油脂科技发展提供一定参考,对于提升我国食用油营养品质和食用安全性,助力实现“健康中国”和“双碳”战略目标可能具有一定的指导意义。