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AIM: To investigate the effects of hypobaric hypoxia in plateau on tear indexes and related anatomical structures in rabbits.METHODS: A total of 18 healthy New Zealand rabbits were selected and randomly divided into plateau group and control group, with 9 rabbits(18 eyes)in each group. The plateau group was housed in the Simulated Climate Cabin for Special Environment of Northwest of China, simulating hypobaric hypoxia at an altitude of 6 000 m. The control group was housed in a clean animal room with atmospheric pressure and oxygen. Changes in the tear meniscus height and non-invasive tear break-up time were detected by using RHCT-1 corneal topographer dry eye comprehensive analysis system, changes in tear secretion was measured by Schirmer Ⅰ test, before intervention and on the 3, 7 d, 2 and 4 wk. Meanwhile, the changes in tear composition before and after intervention in the plateau environment were analyzed using Raman Spectroscopy. The histopathological changes of the lower lid conjunctiva, cornea, lacrimal gland, and Hardarian gland were observed by hematoxylin-eosin(HE)staining after 4 wk of intervention, and the expression of mucin 5AC(MUC5AC)in conjunctiva was detected by immunohistochemistry.RESULTS: Compared with the control group, Schirmer Ⅰ test, tear meniscus height, first and average non-invasive tear break-up time in the plateau group decreased significantly since 3 d, and the difference was significant with the extension of observation time(P

为从油料组分层面探究同为高油酸油料制取的油脂风味差异,以油莎豆和高油酸花生仁为原料制备浓香油莎豆油和浓香花生油，对原料的氨基酸组成和糖类组成进行测定，分析两种油料烘烤前后氨基酸和还原糖含量变化，考察其对两种浓香型油脂风味的影响。采用同时蒸馏萃取结合气相色谱质谱联用技术（SDE-GC-MS）对浓香油莎豆油和浓香花生油进行挥发性成分测定，结合气味活度值（OAV）、气相色谱-嗅闻-质谱（GC-O-MS）和感官评价对两种浓香型油脂的特征香味进行比较。结果表明：油莎豆中的氨基酸总含量（4.27 g/100 g）显著低于高油酸花生仁（38.34 g/100 g）， 但葡萄糖含量和果糖含量（分别为1.80、1.24 g/100 g）均显著高于高油酸花生仁（分别为0.52、0.46 g/100 g）；烘烤后，油莎豆中赖氨酸、天冬氨酸、酪氨酸、谷氨酸含量降低，高油酸花生仁中谷氨酸、天冬氨酸、酪氨酸、苯丙氨酸含量明显降低。浓香油莎豆油和浓香花生油中分别检测到14类122种挥发性成分和12类89种挥发性成分，挥发性成分总量分别为25.69 mg/kg和21.94 mg/kg。浓香油莎豆油中挥发性成分含量由高到低依次是醛类、吡嗪类、酚类、烷烃类、呋喃类、酯类、酮类等，浓香花生油中依次是吡嗪类、醛类、烷烃类、酮类、呋喃类等。浓香油莎豆油的关键风味成分有20种，其中醛类的风味贡献度最大，其次是吡嗪类，浓香花生油的关键风味成分有14种，其中吡嗪类的风味贡献度最大，其次是醛类。通过GC-O-MS结合感官评价分析，共鉴定出8种气味活性物质，浓香油莎豆油中甜香味、坚果味的风味特征较明显，浓香花生油中烤花生味、烤杏仁味等风味特征较明显。氨基酸及糖类为参与美拉德反应的重要前体物质，其含量的差异可能是两种浓香型油脂特征风味产生差异的原因。研究结果为同为高油酸油料所制取油脂的风味形成机制提供支持。In order to explore the flavor differences of oils with the same high oleic acid at the level of oilseed composition,fragrant Cyperus esculentus oil and fragrant peanut oil were prepared from Cyperus esculentus and high oleic acid peanut kernels, and the amino acid compositions and sugar compositions of the raw materials were determined, and the change of amino acid and reducing sugar contents before and after roasting of the two oilseeds were analyzed to investigate their effects on the flavor of the two fragrant oils. Simultaneous distillation extraction combined with gas chromatography-mass spectrometry (SDE-GC-MS) was used to determine the volatile components of fragrant Cyperus esculentus oil and fragrant peanut oil, and the characteristic aromas of the two fragrant oils were compared by combining aroma activity value (OAV), GC-O-MS and sensory evaluation. The results showed that the total amino acid content of Cyperus esculentus (4.27 g/100 g) was significantly lower than that of high oleic acid peanut kernels (38.34 g/100 g), but the glucose content and fructose content (1.80, 1.24 g/100 g) were significantly higher than that of peanut kernels (0.52, 0.46 g/100 g); after roasting, the contents of lysine, aspartic acid, tyrosine, and glutamic acid in Cyperus esculentus were reduced, and the contents of glutamic acid, aspartic acid, tyrosine and phenylalanine in high oleic acid peanut kernels were significantly lower.14 types of 122 volatile components and 12 types of 89 volatile components were detected in fragrant Cyperus esculentus oil and fragrant peanut oil, and their total volatile components content were 25.69 mg/kg and 21.94 mg/kg, respectively. The descending order of volatile components in fragrant Cyperus esculentus oil was aldehydes, pyrazines, phenols, alkanes, furans, esters, ketones, etc. , and that in fragrant peanut oil was pyrazines, aldehydes, alkanes, ketones, furans, etc. Fragrant Cyperus esculentus oil had 20 key flavor components and flavor contribution of aldehydes was the highest,followed by pyrazines, while fragrant peanut oil was the opposite, with 14 key flavor components. A total of 8 odor active components were identified by GC-O-MS combined with sensory evaluation analysis. The flavor characteristics of sweet aroma and nut aroma were more obvious in fragrant Cyperus esculentus oil, and the flavor characteristics of roasted peanut aroma and roasted almond aroma were more obvious in fragrant peanut oil.Amino acids and sugars are important precursors involved in the Maillard reaction and their content differences have an effect on the difference in the characteristic flavors of the two oils. The results provide support for the flavor formation mechanism of oil made from the same high oleic acid oilseeds.

Objective: To study the effects of different drying processes on the quality of high moisture wheat. Methods: Investigates the changes of wheat quality under different drying processes in three dimensions: appearance quality, nutritional quality and processing quality. Three indicators, namely colour, wet gluten content and drying rate, were selected as response values and combined with response surface analysis to predict the optimal drying process for high moisture wheat. Results: Drying temperature was the main influencing factor. As the temperature increased, the colour of the wheat deepened, the crude protein content decreased, the wet gluten content decreased, the water absorption of the dough increased, the formation time increased, the stabilization time increased, the degree of weakness decreased, the flour quality index under increased, The wheat skin changed from a small raised rectangle to a small sunken pit, and the internal starch granules changed from a smooth round or oval shape to a rough irregular shape. The optimal processing conditions of the response surface were drying temperature 45 ℃, wind speed 0.94 m/s, tempering time 30.4 min. The colour L* 58.811, the wet gluten content of 27.292%, the drying rate of 8.146×10-2%/min and the comprehensive score of 0.613 were obtained with this parameter. Conclusion: The study proved that the optimization of the hot air drying process improved the post-drying quality of wheat to some extent on the basis of ensuring the drying efficiency.

为给油莎豆油精炼过程的品质控制提供支持，对2个不同品质的油莎豆原油样品进行水化脱胶、碱炼脱酸、吸附脱色和蒸馏脱臭，对精炼过程中油莎豆油质量指标，脂肪酸、甘油酯组成和营养成分含量进行检测，分析原油品质和精炼过程对油莎豆油综合品质的影响。结果表明：虽然2个不同品质的油莎豆原油的酸价（KOH）有明显差异（分别为2.03、12.21 mg/g），但精炼后酸价（KOH）（分别为0.16、0.33 mg/g）和过氧化值（均为0.01 g/100 g）均显著优于LS/T 3259—2018《油莎豆油》中的指标要求；磷脂含量分别从6 874.10、312.29 mg/kg降至88.61、88.28 mg/kg，脱除率分别为98.71%和71.73%；脂肪酸组成及含量没有明显变化，甘油酯组成中甘三酯含量有所增加（分别从98.46%、97.68%升高至98.74%、98.06%），但变化不显著；甾醇总量分别从220.21、253.44 mg/kg 降至175.14、182.33 mg/kg；多酚含量分别从26.38、88.65 mg/kg降至8.45 mg/kg和未检出；维生素E总量分别从225.91、177.33 mg/kg降至180.01、13.09 mg/kg。品质不同的油莎豆原油经精炼后，质量指标都能达到行业要求，但酸价高的油莎豆原油精炼过程中有益伴随物损失较大。 In order to provide support for the quality control of Cyperus esculentus oil refining process, two samples of Cyperus esculentus crude oil with different quality were degummed by hydration, deacidified by alkali refining, bleached by adsorption and deodorized by distillation. The quality index, composition of fatty acid and glyceride, and nutrient content of Cyperus esculentus oil in the refining process were detected, and the influence of crude oil quality and refining process on the comprehensive quality of Cyperus esculentus oil was analyzed. The results showed that although the acid value of two different qualities of Cyperus esculentus crude oil was significantly different (2.03 mgKOH/g and 12.21 mgKOH/g respectively), the acid value (0.16 mgKOH/g and 0.33 mgKOH/g respectively) and peroxide value (both 0.01 g/100 g) after refining were significantly better than those in LS/T 3259-2018 Cyperus esculentus oil. During refining, the phospholipid content decreased from 6 874.10 mg/kg and 312.29 mg/kg to 88.61 mg/kg and 88.28 mg/kg respectively, and the removal rates were 98.71% and 71.73% respectively. The fatty acid composition and content of Cyperus esculentus oil did not change obviously, and the triglyceride content in glyceride composition increased (from 98.46% and 97.68% to 98.74% and 98.06%, respectively), but the change was not significant. Total sterol content decreased from 220.21 mg/kg and 253.44 mg/kg to 175.14 mg/kg and 182.33 mg/kg, respectively. Polyphenol content decreased from 26.38 mg/kg and 88.65 mg/kg to 8.45 mg/kg and not detected, respectively. The vitamin E content decreased from 225.91 mg/kg and 177.33 mg/kg to 180.01 mg/kg and 13.09 mg/kg, respectively. After refining, the quality indexes of Cyperus esculentus oil with different crude oil quality can meet the industry requirements, but the beneficial companion loss of Cyperus esculentus crude oil with high acid value is great during refining

Drying treatment can significantly increase the oil yield of tiger nuts, and the full utilization of starch by-products in tiger nut meal is an important aspect of improving its industrial value. Consequently, the effects of roasting, microwave and roasting treatments on the structure, functional properties and in vitro digestive characteristics of tiger nut starch were investigated. The results showed that compared to that of CS (untreated control starch), samples of BS (baked starch), MS (microwaved starch), and RS (roasted starch) showed deeper color, surface cracks, partial aggregation on the granules, and larger particle size. In addition, baking, microwave and roasting treatments all decreased the relative crystallinity and short-range ordering of the tiger nut starch, explaining the decrease in enthalpy in the DSC results, the increase in the stability of the freeze-thaw, the solubility and the swelling. From the rheological analysis of starch, it was found that the gel structure of tiger nut starch decreased after the aforementioned treatments. This indicates that the branched chain starch was damaged, which impacing the digestibility of the starch. Further in vitro digestion tests demonstrated that three drying treatments increased slow-digestible starch and resistant starch content. Among them, microwave drying treatment had a significant effect on the structural and functional properties of the isolated starch of tiger nut. This study aimed to provide theoretical guidance for the comeplete utilization of tiger nut starch. [ABSTRACT FROM AUTHOR]

In this study, a heat and mass transfer model for hot air drying of wheat grain piles based on the discrete-continuous medium assumption method was established to understand the wet heat transfer law inside the wheat grain pile during the drying process. Simulations using COMSOL Multiphysics software were then carried out to study the heat transfer and moisture migration in the porous pile structure of wheat under the conditions of 20 °C ambient temperature, 60 °C air temperature, and 1 m/s air speed. The model was validated in combination with wheat hot air-drying experiments. The experimental results showed that the established model can reflect the drying process of the grain pile well, and the experimental values were in good agreement with the predicted values. The temperature, humidity, and flow fields in the wheat pile were unevenly distributed. The temperature distribution of the wheat pile showed a high temperature in the edge region and a low temperature in the center region, the maximum temperature difference reached around 8 °C. The moisture distribution of the pile showed the opposite trend, with lower moisture in the edge region and higher moisture in the center region. The humidity of the upper layer of wheat in the grain pile showed an upward trend over a period of time due to the influence of rising steam, the maximum moisture difference reached about 15%. The velocity of the edge region with a large pore rate was large, and obvious vortex regions were found in the grain layer. The local speed reaches about 5 times the inlet wind speed. Based on the CFD-DEM medium coupling method, the complex pore structure within the grain stacking structure can be accurately constructed, and a mathematical model can be established on this basis, providing a new approach for simulating the moisture and heat transfer of grain stacking structures. [ABSTRACT FROM AUTHOR]

In this study, four species of bacteria Escherichia coli, Staphylococcus aureus, Bacillus anthracis and Bacillus subtilis, as well as three species of fungi Rhizopus oryzae, Aspergillus Niger and Penicillium sp. were selected as research objects to investigated the antibacterial effect and maximum dilution ratio of extract of Eucommia ulmoides leaves which was treated with different elution components by perforation and double dilution. The results show that each polar elution component of the ethyl acetate fraction and the n-butanol fraction of the extract can inhibite the growth of Escherichia coli, Staphylococcus aureus and Bacillus anthracis. Among them, the most effective antibacterial effect is to Bacillus anthraci. The diameter of the maximum antibacterial zone reaches 22 mm. However, Bacillus subtilis and three fungi are not significantly inhibited. There is little difference in the inhibition of bacteria and fungi by different polar eluting components. The maximum effective dilution factor of these components on Bacillus anthracis reaches 32 times. [ABSTRACT FROM AUTHOR]

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To determine the best combination of parameters for honey drying with ultrasonic vacuum drying technology, this study evaluated the effect of ultrasonic power and frequency on the drying kinetics of honey. Three ultrasonic frequencies and two ultrasonic powers were chosen to investigate the influence on water transport, storage stability and microstructural changes during ultrasonic vacuum drying. Among all the conditions studied, 40 kHz 80 W was found to be the best with fastest drying rate and shortest drying time. Through the low-field nuclear magnetic resonance analysis, the ultrasonic vacuum drying of honey could effectively remove bound water at 40 kHz frequency coupled with high ultrasonic power. Ultrasonic power and frequency played a positive role in accelerating the mass transfer process. Meanwhile, the honey powder dried at 28 kHz 40 W had the best storability with the highest glass transition temperature (Tg) value measured by differential scanning calorimetric. According to the changing trend of Tg, the average molecular weight of carbohydrate in honey was altered due to the impact of different ultrasonic power and frequency, especially at 40 kHz 80 W. The effects on mass transfer properties were confirmed with microstructural observations using scanning electron microscopy. The new findings on the impact of power and frequency on ultrasonic vacuum drying can be potentially beneficial for future food processing development. [ABSTRACT FROM AUTHOR]

Dehydration can significantly extend the shelf life of dried carrots and still retain nutrition of provitamin A carotenoids. In vitro digestion model was used in this study to assess the effect of drying temperatures of heat pump and dietary fat on the bioaccessibility of β-carotene in carrots. Also, low-speed centrifugation was employed to obtain β-carotene release rate in supernatant. Microfiltration was applied to obtain β-carotene micellar rate in micelle phase. These assays were used as indicators to assess the bioaccessibility of the β-carotene. Despite higher drying temperatures had a negative effect on the retention rate of β-carotene in carrots, it showed a positive impact on the micellar rate. In addition, dietary fat significantly increased the release rate and micellar rate of β-carotene for both fresh carrots and dried carrot products, with the highest release rate and micellar rate obtained when 10% dietary fat was added. Therefore, the heat pump drying process and dietary fat can significantly improve the bioaccessibility of β-carotene in carrots, which may increase the β-carotene bioavailability to human. [ABSTRACT FROM AUTHOR]