Influence of Flavor on Goat Feeding Preferences

Goat feeding preferences for straw pellets flavored with ryegrass (Lolium perenne, cv. Belida) or white clover (Trifolium repens, cv. Huia) aromatic extracts, obtained by means of a cold aromatic extraction method, were assessed with cafeteria trials. Prior to the trials, odor differences between the two plant species, the two aromatic extracts, and the straw pellets sprayed with the two aromatic extracts were verified using sensory analysis performed by 30 human panelists. Since odor differences observed among fresh samples were still detectable in aromatic extracts and moistened pellets, the extraction method was considered effective in reproducing plant odors. Straw pellets sprayed with either distilled water (W) or ryegrass (R) or clover (C) aromatic extracts were used to assess flavor preferences of 12 female Rossa Mediterranea goats. Sprayed pellet preference was evaluated in two sessions conducted in two consecutive weeks. Each session consisted of three two-choice presentations performed on three consecutive days. In both sessions, food intake, proportion of food intake, time spent feeding, and proportion of time spent feeding were significantly affected by pellet type (0.05 > P > 0.001). In particular, straw pellets sprayed with ryegrass extract were highly selected compared to those sprayed with clover (0.01 > P > 0.001) or water (0.01 > P > 0.001). In addition, in the second session, the clover extract was preferred to distilled water (0.05 > P > 0.01). The results of this study gave two main indications: first, goat selectivity for ryegrass against clover was consistent even when straw pellets sprayed with odors of these plants were offered, and secondly, the addition of aromatic extracts to straw pellets increased the preference for pellets.     

微波辐射-同步冷却法合成3种2-甲基-2-烷基-1,3-二噻烷

本文描述了一种合成2-甲基-2-烷基-1，3-二噻烷香料化合物的便捷方法。采用微波辐射-同步冷却技术，1，3-丙二硫醇分别与丁酮、戊酮和己酮在一水合对甲基苯磺酸催化下以微波功率63W反应15min，合成了2-甲基-2-乙基-1，3-二噻烷、2-甲基-2-丙基-1，3-二噻烷和2-甲基-2-丁基-1，3-二噻烷，产率分别为74．8％、72．4％和76．8％。采用元素分析、FTIR、^1H NMR和GC-MS对3种产物进行了结构鉴定，并进行了初步香气评价。     

论新地方主义建筑的发展

新地方主义是一种强调地方特色和民俗风格的设计倾向，强调乡土味和民族化的设计流派，中华传统的民居建筑在做了历史经典的准备基础上，借鉴一些亚洲国家成功经验，必能孕育出中国的新地方主义建筑风格。     

Effect of post-treatment microwave vacuum drying on the quality of 3D-printed mango juice gel

Abstract

This paper presents the development of three-dimensional (3D)-printed mango juice gel with microwave vacuum drying (MVD) post-treatment. In this study, the post-treatment MVD was used to improve the quality of the 3D-printed mango juice gel. The flavor, texture, water status distribution, and dielectric properties of products with different drying times (0, 2, and 4?min) were compared. We found that 3D printed products under a post-treatment of 4?min of MVD had the best shape retention and shape accuracy. 3D-printed mango juice gel under 4?min of MVD post-treatment exhibited a compact gel system with the highest ratio of bound water, as well as the highest hardness (445.19?g) and gumminess (89.11), and the lowest the relative dielectric constant (26.40) and dielectric dissipation factor (14.74). Also, samples evaluated under different drying times could be distinguished by comparing the responding signals of the e-nose. Based on these results, it was concluded that the MVD method is a promising way to improve the quality of 3D printed food.     

ESTIMATION OF THE EFFECT OF PRODUCT SHRINKAGE ON THE DRYING TIMES,HEAT INPUT AND CONDENSER LOAD OF THE PRIMARY AND SECONDARY DRYING STAGES OF THE LYOPHILIZATION PROCESS IN VIALS

ABSTRACT

The effects of cake shrinkage on the drying times and energy requirements of the primary and secondary drying stages of the freeze drying process involving the drying of a material in a vial, are estimated through the construction and solution of an extended unsteady state and spatially multidimensional model that accounts for the changes introduced by cake shrinkage on the internal and external mass and heat transfer mechanisms of the freeze drying     

杭白菊浸膏中香气活性成分分析

香气是评价浸膏质量的重要标准之一,该文为构建浸膏质量标准提供基础数据。采用固相微萃取法(SPME)和溶剂辅助风味蒸发(SAFE)两种前处理方法,结合气相色谱-质谱联用(GC-MS)对杭白菊浸膏的挥发性成分进行了分析,同时采用气相色谱-嗅觉检测技术(GC-O)和香气提取物稀释分析(AEDA)对浸膏中的香味活性成分进行了测定。结果表明:两种前处理方法(SPME和SAFE)结合气质联用仪共检测出119种化合物,醇类30种,酸类6种,酯类28种,醛类4种,酮类12种,烃类36种,其他3种,其中,萜烯类及其含氧衍生物为主要化合物,同时SAFE较SPME法检测到的化合物数量更多;GC-O结合AEDA分析共筛选出35种香气活性成分,风味稀释因子(FD因子)较高的活性成分有芳樟醇(2187)、α-石竹烯(729)、苯乙酸乙酯(729)、己酸乙酯(729)、异戊酸乙酯(729)、α-蒎烯(243)、α-松油醇(243)、异戊酸(243)。     

Mathematical Modeling of Heat and Mass Transfer during Convective Dehydration of an Anisotropic Cylindrical Foodstuff

Two‐dimensional, unsteady‐state mass transfer was studied for air drying of an anisotropic finite cylindrical body. A mathematical model was developed for predicting the temperature of the drying sample at any time and moisture in any position in the drying sample at any time. The anisotropic nature of the drying material was considered in the mathematical model by taking into account the different moisture diffusivities in the axial and radial directions. A cut fresh green bean was used as an anisotropic material and a pilot‐scaled dryer was set up to investigate the drying behavior of this foodstuff. Several length‐to‐diameter ratios of fresh green beans were considered and the mathematical model was validated by comparison of the predicted values of average moisture content with the experimental data. The model was used to predict the moisture distributions inside the drying samples. Different moisture content distributions in the axial and radial directions during drying confirms the anisotropic nature of cut green bean samples. © 2013 Wiley Periodicals, Inc. Heat Trans Asian Res; Published online in Wiley Online Library ( wileyonlinelibrary.com/journal/htj ). DOI 10.1002/htj.21119     

肉味香精前体物的制备技术研究

本文研究了以天然动植物资源(猪骨素、辛香料等)为主要原料,不同条件对酶解和美拉德反应肉味香精前体物的影响,确定了相对优化的胰蛋白酶水解猪骨素的最佳工艺条件和美拉德反应的基础配方。     

选择加氢法改进豆油下脚料制油酸酰胺的稳定性

为改进豆油下脚料生产的润滑剂油酸酰胺碘值高、放置一段时间后迅速变黄等稳定性差的缺点．采用骨架镍催化剂选择性加氢油酸酰胺。使其中的亚油酸酰胺、亚麻酸酰胺等不饱和组分大部分转化力油酸酰胺而被除去，提高油酸酰胺的含量和使用性能。最佳反应条件为：反应温度160℃。反应压力0．4MPa，反应时间3．0h，催化剂用量3％。采用碘值结合放置后目测的方法进行了产品分析和评估。     

烟草味电子烟油中挥发性成分分析

采用二氯甲烷对3家公司的5种电子烟油样品进行萃取,并用气-质联用（GC-MS）法鉴定。通过对NIST 11谱库的检索,对5种样品中挥发性成分进行了比较分析。结果表明5种样品中的挥发性成分差别较大,共鉴定出40种挥发性成分,依据作用或来源分为雾化剂、烟叶提取物和薄荷提取物三类。其中相对含量水平较高且在5种样品中都检出的成分是丙二醇、烟碱和甘油。3家公司的5种烟草味电子烟油在抽吸品质上有所差异,C公司样品在抽吸感官感受上相较其他两家公司样品具有明显优势,其中样品C1又略好于C2。比较发现,C公司电子烟油的挥发性成分中含特有的8种多甘醇类化合物,可能是这些物质的协同作用而改善了抽吸品质。