Small-molecule polysaccharides and polyols are widely used as protectants in probiotic fruit and vegetable. This study investigated the effects of glucose, trehalose, sorbitol, glycerol, and their combinations on pore microstructure and quality attributes of freeze-dried strawberry slices enriched with Lactobacillus plantarum. Compared with single protectants and controls, compound protectants resulted in higher viable L. plantarum count; a more uniform, stable, and well-developed porous microstructure; lower equilibrium hygroscopicity; improved volatile compound profiles; and brighter color characteristics. In the compound group, hardness and chewiness (from texture profile analysis), penetration hardness, and penetration work were 40.27%, 38.38%, 56.70%, and 39.36% higher, respectively, than those in the control group. Higher porosity rate, larger pore equivalent diameter, pore wall thickness, isolated pore volume, and smaller connected pore equivalent diameter were significantly correlated with improved mechanical properties and sensory scores. These findings support the application of polysaccharide and polyol protectants in freeze-dried probiotic fruit and vegetable.

Pectin is a commonly used food additive, however, the freeze-drying characteristics of restructured strawberries with pectin addition are currently unclear. This study investigated the effects of 0, 3, 6, and 9 g/kg pectin addition on moisture content, drying date, moisture ratio, water state distribution during the freeze-drying process, as well as water uptake and volatile compounds of freeze-dried restructured strawberry blocks (FRSB). The drying rates at the four levels of pectin addition presented similar early acceleration and later deceleration trends. Moisture content in FRSB was linearly predicted by peak area of low field nuclear magnetic resonance with R2 higher than 0.90 for all the four groups. High pectin addition resulted in higher sulfides response values. Compared with the control group, the water uptake of FRSB samples in 0, 3, 6, and 9 g/kg group decreased by 12, 22, and 31%, respectively, which can be reasoned that pectin addition shielded hydrophilic functional groups from external water molecules. These results provide guidance for improving the drying characteristics, volatile compounds, and water uptake of FRSB by adding pectin.

在人类文明的发展中,烹饪饮食文化是其最重要的组成部分.世界各国的烹饪饮食文化各具特色,而在数千年中华文化中积淀和发展而来的鲜明而独特的中华烹饪饮食文化更是独树一帜.饮食文化的发展史本质上就是人类的发展史,从裹腹之需到精神享受,从摄取营养到养生保健,从单一的充饥到复杂的社会属性,无不体现出人类为追求美好生活而不懈努力的永恒主题.十八世纪工业革命使传统的烹饪技术发生了翻天覆地的变化,从传统的烹饪术派生而来的现代食品工业既区别于传统烹饪,又与传统的烹饪术是一脉相承的.

Curriculum ideological and political education is the fundamental task of implementing moral education and cultivating people in colleges and universities, and also the basic requirement for the development in the new era. The concept of OBE is results-oriented education, which is a reverse design education concept of 'output -oriented, student-centered, teacher-led organization and continuous improvement'. Principles of Food Technolog is the core course of food major, which plays a vital role in cultivating high-quality professionals in the food industry. Therefore, it is urgent for teachers to explore the ideological and political elements contained in the knowledge system and penetrate into each teaching link in the teaching process. Based on the characteristics of the course, teaching objectives and teaching content, this paper explores the ideological and political elements in each chapter deeply, and constructs such elements based on the concept of OBE and implements through the combination of online and offline teaching. The teaching of specialized courses and curriculum ideological and political education in the curriculum go in the same direction to achieve a synergistic effect. Through the construction and implementation of the ideological and political elements of the course, students can improve their sense of identity and professional ethics of food major, and help students form a correct world outlook, outlook on life and values. At the same time, the research results of the course are expected to provide appropriate reference and reference for the construction and effective implementation of other professional courses.

根据专业人才培养要求及"食品工艺学"的课程特点,构建了考勤+随堂测试、单元测试、作业、小组讨论、专题汇报、期末考试等方式的多元化理论教学的考核评价体系.通过改革实践发现,多维度考核能够调动学生学习的积极性,加强平时对知识的消化吸收,提高了教学效率,同时促进了学生的个性化和创新能力的培养.

In this study, we examined the effects of marination with five edible mushroom powders (3%, m/m) on the quality attributes and protein changes of pork longissimus dorsi compared to meat marinated with 0.2% papain and distilled water (control group). The results indicated that pork samples marinated with edible mushrooms displayed better water retention and lower shear force, especially in the 3% Hypsizygus marmoreus (HM) group (12.50 ± 0.73 N). Ultrastructural observation results showed that the Z-disk and M-line of the pork samples marinated with edible mushrooms were fractured and weakened. Furthermore, the degradation extent of desmin in the HM-marinated pork samples was obviously increased (43%) in comparison to the papain group (only 15%), which was further confirmed by the results of the myofibril fragmentation index. Overall, the pork samples marinated with 3% HM exhibited better quality traits among all groups and might be a potential strategy to improve tenderness.

为探索一体化冻干(integrated freeze-drying,IFD)、传统冻干(conventional freeze-drying,CFD)和热风干燥(air drying,AD)3种干燥方法对榴莲中主要呈味成分的影响,采用高效液相色谱法跟踪测定3种干燥过程中榴莲样品的游离氨基酸和可溶性糖含量,并进行主成分分析(principal component analysis,PCA)和聚类分析.结果表明,新鲜榴莲在IFD和CFD中经过冻结后其游离氨基酸总含量显著下降(P<0.05),而在3种干燥过程中游离氨基酸总含量均呈先升后降的趋势;对于榴莲干燥样品,游离氨基酸总含量IFD最高(P<0.05),CFD与新鲜样品无显著差异(P>0.05),AD最低(P<0.05).榴莲中游离氨基酸主要为甜味氨基酸和鲜味氨基酸,干燥样品中鲜味氨基酸含量IFD、CFD均显著高于新鲜样品(P<0.05),AD最低;IFD和CFD干燥样品的甜味氨基酸含量均与新鲜样品无显著差异(P>0.05),而AD干燥样品显著低于新鲜样品.榴莲中可溶性糖主要为蔗糖、葡萄糖、果糖和麦芽糖,在3种干燥过程中榴莲可溶性糖总含量均呈下降趋势,新鲜榴莲经过3种干燥后可溶性糖总量由高到低分别是IFD、CFD、AD、新鲜样品,差异显著(P<0.05).利用PCA提取出5种主成分,分别解释总变异量的41.181％、20.588％、14.561％、9.057％和5.992％.通过PCA综合分析和聚类分析得出,3种不同干燥方法对榴莲样品游离氨基酸和可溶性糖风味产生一定差异,综合得分IFD样品相对较高,CFD样品次之,AD样品相对较低.

蛋白质氧化是活性氧或氧化应激的副产物引起蛋白质的共价修饰.蛋白质氧化的结果主要是引起氨基酸侧链基团的修饰、蛋白质肽链骨架的断裂以及蛋白质分子内和分子间的交联或聚集,从而改变蛋白质的分子结构与功能,最终导致鲜肉品质的变化.目前,鲜肉在市场上的主要包装方式有托盘包装、真空包装、真空贴体包装和气调包装4种.不同包装方式在冷藏期间由于含氧量的不同引起蛋白质氧化程度不同,进而对鲜肉的品质产生重要影响.本文对市场上常用的鲜肉包装方式、蛋白质氧化的定义和机理以及不同包装方式下蛋白质氧化对鲜肉品质的影响进行综述.

"食品添加剂"课程是食品科学与工程专业开设的最重要专业课之一,具有极强的应用性和实践性,因此学好该课程对学生就业具有重要的现实意义.为了提高"食品添加剂"课程的整体教学质量,分析了"食品添加剂"课程在传统教学中存在的一些实际问题,并根据存在的问题从教学内容、 教学方法、 教学实践和考核方式4个方面进行全面具体的改革.实践证明,良好的教学改革不仅能够调动学生主动学习的积极性,提高学习效率,并培养出专业学生分析问题和解决问题的实际能力,还能够提高食品添加剂学科的教学质量,提升教师的整体教学水平.

以新鲜白玉菇为原料,通过测定其营养成分、色泽、复水比、感官评定、质构测定以及微观结构测定,研究热风变温干燥,真空冷冻干燥,红外恒温干燥3种干燥方式对其品质的影响.结果表明:相对于热风变温干燥组和红外恒温干燥组,真空冷冻干燥组的白玉菇样品样品营养成分最高,蛋白质和多糖含量分别为221.16 mg/g和74.25 mg/g.同时,真空冷冻干燥组的复水比、色泽、感官评定和质构特性最好,电镜结果表明真空冷冻干燥组的样品组织结构完整性最好.综合比较,真空冷冻干燥是3种干燥方式中最理想的干燥方式.

以酵素粉、芋头粉和高筋小麦粉为主要原料,研究酵素粉添加量、芋头粉添加量、酵母添加量和白糖添加量对芋头粉面包品质的影响.在单因素实验基础上,采用正交实验确定酵素芋头粉面包的工艺配方.结果表明,酵素芋头粉面包的最佳制作工艺参数为酵素粉添加量3％,芋头粉添加量6％,酵母添加量2％,白糖添加量16％,在此条件下制得的酵素芋头粉面包外表呈金黄色,组织结构蓬松有弹性,口感柔软香甜,具有芋头粉特有的风味.

以不添加任何天然食用胶为对照,分别添加海藻酸钠和亚麻籽胶制备脂肪含量低于5％的低脂香肠,通过测定其蒸煮损失率、保水性、颜色、感官评定、质构特性以及微观结构,研究天然食用胶对西式香肠品质的影响.结果表明:相对于对照组,海藻酸钠替代组和亚麻籽胶替代组的颜色和风味无显著性差异(P＞0.05),而蒸煮损失显著减少(P＜0.05),保水性显著增加(P＜0.05).感官评定、质构测定和扫描电镜结果表明,海藻酸钠替代组和亚麻籽胶替代组的硬度、弹性、咀嚼性和总体接受性均显著性提高(P＜0.05).天然食用胶是多糖类大分子物质中较为理想的脂肪替代物.

Vacuum freezing is an advanced technique for quick freezing and has attracted increased attention worldwide. Compared with traditional freezing, vacuum freezing has advantages of fast cooling rate, short freezing period, and uniform cooling effect. Existing stud-ies on vacuum freezing are limited to liquids, drugs and solid foods. Pleurotus eryngii is rich in protein, polysaccharides and essential amino acids, and a quick freezing can keep it fresh and maintain the nutrients. One concern over the vacuum freezing is its mass loss, but it could be ameliorated by pre-treatments such as adding exogenous water prior to freezing. This paper investigate the efficacy of several pre-treatments, including slicing thickness, blanching and adding exogenous water, on the quality of vacuum-frozen Pleurotus eryngii. The relationship between slicing thickness and water loss ratio after vacuum-freezing was studied, and the impact of adding ex-ogenous water and blanching on vacuum-freezing results was experimentally examined. The results showed that increasing slicing thick-ness reduced the water-loss ratio, and that the amount of exogenous water that was required to reach a zero-water loss after thawing was negatively correlated to the slicing thicknesses at significant level (P<0.05), with a determination coefficient of 0.98. Adding exogenous water could partially or completely compensate the evaporation loss. When the adding exogenous water was less than 20%, water loss from the Pleurotus eryngii slices without blanching was significantly higher than that with blanching, while the opposite was true when the adding exogenous water exceeded 25% (P<0.05). The loss ratio of the vacuum-frozen Pleurotus eryngii slices after thawing without blanching was significantly higher than that with blanching (P<0.01), indicating that blanching might have significantly reduced the moisture in the vacuum-frozen samples as they were positively correlated to the loss ratio after thawing (P<0.01). The loss ratio after thawing without blanching increased with the added exogenous water, yet no significant difference was found between the loss ratio with blanching when the added exogenous water was more than 10% (P>0.01). The total loss ratio and the relative electrical conductivi-ty of the Pleurotus eryngii slices with blanching were significantly higher than those without blanching, and they all decreased with the increase in the added exogenous water. Microstructure analysis revealed that blanching damaged the cell network in tissues, and adding exogenous water prior to vacuum-freezing could reduce water evaporation from the tissues, thereby ameliorating cellular structure dam-age. In summary, our results suggested that the optimal pre-treatment for vacuum-freezing the Pleurotus eryngii slices were: slicing at 3 mm of thickness, blanching with 90°C hot water for 1 minute, and adding 30% of exogenous water.

为了研究不同组合干燥方法对水蜜桃脆片品质的影响,以真空冷冻干燥方法为基础和对照,并将其与热风、微波、气流膨化3种方法进行组合干燥对比实验和品质测试分析.结果表明,冻干-微波组脆片样品色泽改变最大,综合色差△E值显著高于其他3组(p＜0.05);在微观组织结构方面,冻干组形成了饱满的多孔网络骨架,孔隙率高,而冻干-微波组样品细胞组织坍塌严重、结构致密,冻干-热风组、冻干-气流组的微观组织形态相近且介于冻干、冻干-微波组2组之间;4组样品直径收缩率由高到低分别是冻干-微波、冻干-热风、冻干-气流、冻干,差异显著(p＜0.05);冻干-微波组脆片吸湿率显著低于其他3组,冻干组脆片吸湿率最高;冻干-微波组脆片硬度和脆度远高于其他3组,冻干组脆片最小;组织微观形态观察结果能较好地反映水蜜桃脆片上述品质的差异.4组水蜜桃脆片中,冻干,微波组综合品质最差,冻干组最佳,而其他2组综合品质介于中间.

Modified atmosphere packaging (MAP) storage has become a useful technique for extending the shelf life of fruit and vegetables. However, the success of MAP depends on many factors, including types of fresh products, storage conditions, and the characteristics of the packaging films. To achieve the optimal gas composition in the package headspace and improve the postharvest quality of fresh produce, the packaging film with appropriate barrier properties needs to be selected. This study aimed to predict the film thickness by applying produce respiration rate and package film permeability data measured in given product weight and storage conditions. An available film (eg, 25‐μm‐thick low‐density polyethylene) was used to pack fresh produce, and the respiration rate of fresh produce and in‐package O2 and CO2 concentrations at steady state were measured. Permeability of the film was calculated based on mass balance, and the thickness of the film could be predicted if the recommended target O2 and CO2 concentration was obtained from the literature. To validate the predicted thickness value, an experiment was conducted by packaging fresh table grapes in bags of the predicted thickness. The effect of packaging with different film thicknesses on the quality of the fruit was determined. The results showed good agreement between the predicted and the experimental in‐bag O2 and CO2 concentrations, and the MAP with predicted thickness (90 μm) film was more effective in maintaining postharvest quality of grapes during low‐temperature storage than the thinner films (30 and 60 μm) and the control.

Chlorine dioxide (ClO2) gas was used to control berry decay and rachis browning of table grape due to its antimicrobial and anti-browning properties. It was proposed that if ClO2 gas is fully absorbed by the fruit, the maximum total ClO2 dose can be calculated based on the maximum allowable residual concentration. To avoid possible bleaching effects on grape peel from high concentrations of ClO2, the total amount of ClO2 gas needs to be injected into the packages in many small doses at specific time intervals over the course of the 90-day storage period. Spoilage microorganism counts, decay rate, electrolyte leakage, rachis browning and residual ClO2 in berry were investigated. The results showed that ClO2 treatment could significantly reduce berry decay and rachis browning (p.05) compared to the control. Grape treated with 1.0 mg L-1 ClO2 6 times at 15-day intervals maintained better fruit quality without any risks from the residual ClO2. Practical applicationsThe present research found that ClO2 treatment is useful for improving the microbial safety of grapes and reducing berry decay and rachis browning during storage, and low doses of ClO2 spread over many treatment can yield better results.

选用真空包装作为对照,通过测定pH、颜色、总色素含量、脱氧肌红蛋白、氧合肌红蛋白和高铁肌红蛋白的相对比例、脂肪氧化以及高铁肌红蛋白还原酶活性,研究托盘包装和气调包装对宰后成熟过程中牛肉颜色的影响机制.结果表明:相对于真空包装,托盘包装牛肉样品的pH较高,而气调包装牛肉样品的pH较低,托盘包装和气调包装牛肉样品的L*值和b*值较高(P＜0.05),气调包装能够有效地维持牛肉样品颜色稳定性(P＜0.05),而托盘包装在维持颜色稳定性方面相对较差,托盘包装和气调包装的牛肉样品脂肪氧化程度较高(P＜0.05),脱氧肌红蛋白含量和高铁肌红蛋白还原酶活性相对较低.

以南高丛蓝莓果实为材料,以不同剂量的SO2缓释保鲜剂(用量分别为新鲜蓝莓质量的0.125％、0.250％、0.375％、0.500％)对果实进行处理,研究其对蓝莓果实腐烂率、漂白率、感官品质及SO2残留量等的影响.结果表明,SO2剂量越大,抑菌效果越好,腐烂率越低,但容易造成果实脱色漂白现象加重及SO2残留量增加,其中0.375％、0.500％剂量的处理组果实有明显的脱色漂白现象;而当SO2缓释保鲜剂用量为蓝莓质量的0.250％时,能获得较好的保鲜效果,果实腐烂率和漂白率均较低,如果在贮藏的中途(贮藏30 d)更换新的保鲜剂其保鲜效果更好,且在保鲜结束时果实的SO2残留量小于10 mg/kg,符合食品安全标准.

The effect of hot-water blanching (HWB) on drying characteristics and product qualities of dried apple slices with the novel integrated freeze-drying (NIFD) process was investigated by comparing with 3 different FD methods. Compared with the NIFD process without HWB pretreatment (VF-FD), the NIFD process with HWB pretreatment (HWB-VF-FD) resulted in a significantly higher mass loss and more sufficient freezing in vacuum-frozen samples, significantly higher rehydration ratio (RR), higher shrinkage ratio (SR), smaller Vitamin C (VC) content and lower hardness and better apparent shape in freeze-dried samples, and fewer change to the color of the dried or rehydrated samples (p<0.05). Compared with the conventional FD process with HWB pretreatment (HWB-PF-FD), HWB-VF-FD cost significantly less processing time and FD time and obtained significantly higher RR (p<0.05), almost the equivalent SR, VC content, and hardness, and similar appearance in dried samples. The microstructure of apple cell tissues was analyzed by transmission electron microscopy and scanning electron microscopy to interpret the above differences in drying characteristics and product qualities. The results suggested that the NIFD process of apple slices with HWB pretreatment was a promising alternative method to decrease drying time, achieve similar product quality, and simplify the process steps of the conventional FD technology.

In order to improve the quality of Arctium lappa L.powder,concentrations of maltodextrin,sugar and carboxy methylated cellulose(CMC) were chosen as testing factors,and preparation technology was optimized by orthogonal test with Z-comprehensive analysis method.The Arctium lappa L.powder was dried by dry and wet mixing method of vacuum freezing drying and the effects of two drying methods on the qualities and microstructure of burdock powder were investigated.The results showed that maltodextrin had the significant impact,and the best preparation process of dry mixing method was maltodextrin 15％,sugar 12％ and CMC 0.25％,and the wet mixing method was maltodextrin 25％,sugar 12％ and CMC 0.2％.The microstructure,distribution of particle size and solubleness of burdock powder by wet mixing method were better than those by dry mixing method.