Studying Some Physicochemical Characteristics of Crust Coated with White Egg and Chitosan Using a Deep-Fried Model System

In this paper, the effects of frying time, white egg (0%, 5% and 10% w/w) and chitosan (0%, 0.5% and 1.5% w/w) addition to the batter formulation on the quality of simulated crispy deep-fried Kurdish cheese nugget crusts was studied by using a deep-fried crust model. Moisture content, oil content, color and hardness of the samples were determined. Crust models were fried at 190℃ for 60, 120 and 180 s. Batter formulations and frying time significantly (p < 0.01) affected moisture, oil content, color and hardness of Crust models. Batter formulation contain 10% white egg was found to be an effective ingredient in decreasing oil content of Crust models. The mean moisture and fat content of Crust models formed with batter contained 10% white egg, fried at 190℃, for 180s were 6.207 ± 0.447 and 5.649 ± 0.394. Batters containing 5% white egg and 1.5% chitosan showed the lowest moisture content and the highest oil content among all the formulations. Crust models containing combination of white egg and chitosan were the darkest. Hardness of samples containing chitosan were the highest, specially for ch1.5 The mean hardness in 60, 120 and 180s of frying in this formulation were 21.518 ± 0.481, 36.871 ± 1.758 and 49.563 ± 1.847 respectively.

微波促进Fries重排反应合成(2-羟基-5-甲基)苯基-1-十二酮

在连续微波照射下,由十二酸对甲酚酯的Fries重排反应合成了(2 羟基 5 甲基)苯基 1 十二酮。通过对不同的溶剂、催化剂和反应时间的探索,发现与经典的反应相比,微波促进的反应在120℃下以硝基苯为溶剂、无水三氯化铝作催化剂时,反应时间由2h缩短到8min,收率由89 5%提高到93 4%。

西秦岭夏河-合作地区断裂构造分形结构特征及成矿预测

西秦岭夏河-合作地区是中国重要的金矿及多金属矿床开发地带,区内断裂构造复杂,构造控矿作用显著。文章利用分形理论方法对夏河-合作地区不同方向断裂构造作定量分析,统计计算断裂构造容量维和信息维,结合矿床空间分布分形特征和矿床Fry分析,探讨研究区构造分形特征及断裂与矿床的空间展布关系。研究结果表明,研究区全部断裂容量维1.2374,北东向断裂容量维0.8229,北西向断裂容量维1.2296,近东西向断裂容量维1.0312,全部断裂容量和北西向断裂容量维处于断裂分形临界值(1.22~1.38)区域,显示研究区断裂构造连通性较好。研究区全部断裂信息维1.1118,北东向断裂信息维1.018,北西向断裂信息维1.2296,近东西向断裂信息维1.0217,北西向断裂信息维处于断裂分形临界值区域,反映北西向对矿床的控制最强。断裂构造分形维数可以表征矿床的沉积部位,以容量维、信息维等值线图以及Fry图划分出3个有利成矿区。

A Comparative Study of Stability of Extra Virgin Olive Oil, Virgin Coconut Oil and Grape Seed Oil against Domestic Deep Frying

The aim of this study was to evaluate the relative stability of extra virgin olive oil （EVOO）, virgin coconut oil （VCO） and grape seed oil （GSO） against domestic deep frying. Oil samples were subjected to deep frying at 190 ℃ for 30, 60, and 90 min and then compared with fresh oil samples in terms of fatty acid composition, peroxide value （PV）, p-anisidine value （p-AV）, total oxidation value （TOTOX）, iodine value （IV）, free fatty acid content （%FFA） and total phenolic content （TPC）. Experimental results showed that the changes in the fatty acid composition, p-AV and TOTOX were in the order, GSO 〉 EVOO 〉 VCO throughout the experiment, while PV was in the order, VCO 〉 EVO0 〉 GSO. Meanwhile, the reduction in the IV was in the order, GSO 〉 VCO 〉 EVOO throughout the experiment. On the other hand, the changes in the %FFA were in the order, VCO 〉 GSO 〉 EVO0 throughout the experiment. VCO had the greatest stability against domestic deep frying, followed by EVO0 and GSO had the least stability against domestics deep frying.

Projective Mapping and Product Positioning of Deep Fat Fried Snack

A study was carried out to examine the quality parameters of commercially available popular deep-fried snack-Mu- rukku. Eight samples (four spicy and four salty) of most commonly consumed deep-fried snacks in India, viz., murukku (an extruded strands-like product made from the mixture of rice flour and black gram dhal flour) were analyzed for moisture, oil content, CIE instrumental color (L*a*b*), instrumental texture measurement (breaking strength of murukku strands), aroma finger printing by electronic nose and sensory quality. Quantitative descriptive analysis (QDA) and results showed that sample ‘A’ had highest acceptance and sample D lowest acceptance scores. The results indicated that significant variations were observed in moisture content (2.21 - 3.35%), oil content (30.10 - 34.61%) and textural parameters. Electronic nose technique was found useful in fingerprinting the aroma pattern of market samples in a short time. Descriptive sensory profiling coupled with principal component analysis showed the interrelationship among and between sensory, instrumental, chemical parameters.

Improving oxidative stability of soyabean oil by apple pomace extract during deep frying of french fries

Repetitive use of same oil for deep-frying over extended period results in the production of various harmful compounds thus posing a serious health threat to consumers.Apple pomace,a by-product of apple processing industry is considered a rich source of various bioactive compounds,thus would be of great interest to the frying industry.The aim of this study was to explore the effect of apple pomace extract(APE)on the oxidative stability of soyabean oil during deep frying of french fries and compare it with its highest polyphenolic fraction quercetin(QE)and synthetic antioxidant tertiary butyl hydroquinone(TBHQ).Total phenols(TP)and Total flavonoid content(TFC)of APE obtained from ultrasound assisted extraction(UAE)was found to be(5.58±0.27 mg GAE/g)and(5.42±0.45 mg QE/g)respectively with an antioxidant activity of 76%and(9.9 mM As acid/mg)as determined by DPPH and FRAP assay.Soyabean oil enriched with natural antioxidants show higher thermal stability and quality in terms of various physico-chemical indices and sensory evaluation as compared to control and TBHQ enriched oils.Transfatty acids(TFA)in both control and antioxidant enriched oils during frying were found in higher concentration crossing the legal limit of 2%.The thermal stability of oils conferred by antioxidants follows this order QE˃APE˃TBHQ˃Control.Thus,natural antioxidants obtained from agro-industrial waste have the great potential to replace synthetic antioxidants effectively in conferring stability to deep-fried oils.

固相萃取-高效液相色谱法检测油炸猪肉中丙烯酰胺

建立油炸猪肉中丙烯酰胺的固相萃取-高效液相色谱检测方法。油炸猪肉样品经正己烷脱脂,2 mol/L氯化钠溶液提取,乙酸乙酯萃取,固相萃取小柱净化后,以甲醇-水(5∶95,V/V)为流动相,Hypersi10DS2-C18色谱柱分离,内标法定性、定量分析丙烯酰胺。结果表明:丙烯酰胺的定性检出限为6 μg/kg,定量检出限为20 μg/kg,线性定量范围0.05~1.00 μg/m L,线性相关系数(R2)为0.999 8,本方法的加标回收率稳定在90%~92%范围,相对标准偏差小于3.5%。

油炸用油的种类对炸鱼丸的品质及N-亚硝胺含量的影响

分别使用葵花籽油、花生油、大豆油、玉米油4种植物油炸制鱼丸,通过测定炸鱼丸的质构、蒸煮损失率、脂肪氧化值（thiobarbituric acid reaction substances,TBARs）、亚硝酸盐残留量、N-亚硝胺含量,考察油的种类对炸鱼丸品质和安全性的影响。结果表明：油的种类对各项检测指标都有显著影响。以氧化稳定性最高的花生油炸制的鱼丸,组织状态最好,蒸煮损失小,以氧化稳定性最低的葵花籽油炸制的鱼丸组织状态最差,蒸煮损失大。鱼丸油炸后脂肪发生氧化,样品TBARs值的顺序为花生油（1.0 mg/kg）〈大豆油〈玉米油〈葵花籽油（4.8 mg/kg）组;亚硝酸盐残留量的顺序为花生油（57 mg/kg）〉葵花籽油〉玉米油〉大豆油（36 mg/kg）组;N-亚硝胺含量顺序为葵花籽油（12.52μg/kg）〈花生油〈大豆油〈玉米油（19.91μg/kg）。检测的9种N-亚硝胺中,N-亚硝吡咯烷的含量最高（8.68~11.22μg/kg）,其次是N-二丙基亚硝胺（1.63~1.90μg/kg）和N-二丁基亚硝胺（1.19~1.48μg/kg）。实际生产中应采取选择合适的食用油,并采取相应措施,降低炸鱼丸的脂肪氧化和N-亚硝胺含量。

2-羟基-5-特辛基苯乙酮肟的合成及表征

以四氯乙烯为溶剂,对特辛基苯酚、乙酰氯、无水AlCl3和盐酸羟胺为主要原料,采用分步合成法合成了2-羟基-5-特辛基苯乙酮肟.考察了无水AlCl3用量、乙酰氯的用量、Fries重排温度、肟化反应盐酸羟胺用量以及缚酸剂无水碳酸钠用量对产物产率的影响,实验结果表明,当n(AlCl3)∶n(乙酰氯)∶n(对特辛基苯酚)=1.5∶2∶1,Fries重排温度为120℃,n(Na2CO3)∶n(盐酸羟胺)∶n(对特辛基苯酚)=0.5∶1∶1.产物收率64.9%.对合成产物利用核磁共振进行了结构表征.

萃取剂2-羟基-5-壬基苯乙酮肟的合成

本文以4-壬基酚、乙酰氯、无水AlCl3和盐酸羟胺为主要原料合成了2-羟基-5-壬基苯乙酮肟(HNAO)。合成2-羟基-5-壬基苯乙酮(HNA)时,采用了一步法,以四氯乙烯为溶剂,n(4-壬基酚)∶n(乙酰氯)∶n(AlCl3)=1∶2∶1.2,加毕AlCl3后补加4-壬基酚物质量0.2倍的乙酰氯,回流温度下(120℃)反应6h。HNA收率为98.1%,纯度为79.5%。合成HNAO时,以蒸馏的HNA为原料,以甲苯为溶剂,导辛酸钠为相转移催化剂,n(HNA)∶n(盐酸羟安)∶n(碳酸钠)=1∶1.3∶0.85,75℃下反应4.5h。HNAO收率为97.9%,纯度为88.6%。FT-IR分析结果表明所得中间体及产物与HNA和HNAO特征相符。

2-乙酰基-4-氟苯酚的合成工艺研究

2-乙酰基-4-氟苯酚是一种重要的药物中间体,以对氟苯酚和乙酸酐为起始原料,在吡啶催化下生成4-氟苯基乙酸酯,在AlCl_3催化下通过Fries重排得到2-乙酰基-4-氟苯酚.实验表明:1 mol对氟苯酚在2 mL吡啶催化下和1.4 mol乙酸酐,在90℃油浴下酯化0.5 h,生成4-氟苯基乙酸酯,该反应产率为80%.在1.7 mol AlCl_3催化下,1 mol 4-氟苯基乙酸酯加热到120℃反应6 h重排得到2-乙酰基-4-氟苯酚,该步产率为68.39%.

7-羟基黄酮的五种合成方法

近年来,对黄酮类化合物的化学结构及活性研究已成为药物化学研究的热点和重点之一。7-羟基黄酮具心血管活性,可用作黄酮类选择性冠状动脉扩张剂的中间体,而受到化学家的普遍重视。本文概述了五种合成7-羟基黄酮的主要方法。

2-羟基-5-特辛基苯乙酮肟的合成

研究了用4-特辛基酚、乙酰氯、三氯化铝、盐酸羟胺、异辛酸为原料,用四氯乙烷为溶剂,经3步反应合成2-羟基-5-特辛基苯乙酮肟。在AlCl3作用下,乙酸-(4-特辛基)-苯酯经过Fries重排合成2-羟基-5-特辛基苯乙酮,其优化的合成条件为:以四氯乙烷为溶剂,n(AlCl3)∶n(4-特辛基酚)=1.2∶1,反应温度120℃,反应时间6h。该条件下,2-羟基-5-特辛基苯乙酮的合成产率为90.8%(以辛基酚计),液相色谱纯度为89.2%。产物经IR、1 H-NMR表征确认。由于特辛基的位阻比壬基的高,相同条件下合成的2-羟基-5-特辛基苯乙酮肟的纯度明显比2-羟基-5-壬基苯乙酮肟高;此外,由于高位阻基团的存在,有望提高其对铜的反萃取性能。

天然产物5,6,7,3′,4′-五甲氧基异黄酮的合成(英文)

以3,4-二甲氧基苯乙酸和3,4,5-三甲氧基苯酚为原料,通过一条包括酯化反应、Fries重排、以及Vilsmeier-Haack反应等5步反应的路线合成了天然产物5,6,7,3′,4′-五甲氧基异黄酮。根据3,4,5-三甲氧基苯酚计算目标产物的总收率为76%,利用NMR及元素分析确证了化合物的结构。

11,23-二己酰基-26,28-二甲氧基杯[4]芳烃的合成

以26,28-二甲氧基杯[4]芳烃为原料,经Fries重排反应,选择性地合成了杯[4]芳烃酚羟基对位的二酰化产物:11,23-二己酰基-26,28-二甲氧基杯[4]芳烃,收率最高可达58.4%。通过1HNMR对其结构进行了表征,并对其性质进行了初步研究.

天然产物5,7-二甲氧基-4′-羟基异黄酮的合成

以4-羟基苯乙酸和3,5-二甲氧基苯酚为原料,通过一条包括苄基化、酰氯化、酯化、氢化、Fries重排、以及Vilsmeier-Haack反应等6步反应的路线合成了天然产物5,7-二甲氧基-4′-羟基异黄酮,目标产物的总收率为33%.利用1HNMR、13C NMR及元素分析确证了化合物的结构.

5-氟-2-羟基苯乙酮的制备

以对氨基苯酚为原料,一步进行氨基与酚羟基的双重酯化,三氯化铝/氯化钠条件下进行Fries重排,水解产物进行氟重氮化后加热得5-氟-2-羟基苯乙酮成品。原料廉价,反应条件相对温和,总收率可达54.5%,具有工业生产应用价值。

4'-羟基查尔酮的合成研究

以苯酚和乙酸酐为原料,经酚酯化反应、Fries重排反应、羟醛缩合来合成4＇-羟基查尔酮。对反应的主要因素进行了研究,结果表明：酚酯化反应的温度应控制在125-130℃,乙酸酐和苯酚的摩尔比为0.25∶0.21、反应时间为2.5 h,产率为86%;Fries重排反应的温度应控制在25-30℃,乙酸苯酯和催化剂无水三氯化铝摩尔比为0.15∶0.18、反应时间为24 h,产率为21%;羟醛缩合的反应温度为室温,在稀碱的醇溶液中（0.14g/mL）进行,反应时间为12 h,产率68%。

马里亚纳海沟Challenger Deep的岩石圈流变结构与动力学分析

马里亚纳海沟是西太平洋板块边缘沟-弧-盆体系构造演化的关键地区,其南端的Challenger Deep不仅是地球表面最深点,也是马里亚纳海沟、马里亚纳岛弧、马里亚纳海槽、西马里亚纳洋脊和帕里西维拉海盆的构造汇聚点。开展岩石流变结构与动力学过程研究对于认识Challenger Deep的形成演化具有重要的科学意义。利用综合地球物理资料,通过对重、磁数据的计算分析,研究马里亚纳沟-弧-槽-盆系统的等效黏滞系数和岩石圈强度等流变学特征。利用地震资料,勾绘海沟之下贝尼奥夫带随深度变化的特征以及陡变形态。计算结果表明:对应马里亚纳海沟-岛弧-海槽系统,自由空气重力异常向东凸出,形成弧型异常区;区内异常表现为串珠状线性特征,异常值中间高,两侧低。不同深度岩石圈累积强度比值表明,海沟南北两侧地壳上硬下软,海沟中部地壳上软下硬。在给定应变速率条件下计算的等效黏滞系数东高西低,说明西侧构造体地壳比东侧构造体地壳更容易变形。Challenger Deep岩石圈强度较大,等效黏滞系数较高,具有上硬下软的流变学特征,为板块俯冲在该区的弯曲、撕裂与快速翻转提供了重要条件。地震与重力剖面分析表明,Challenger Deep处的岩石圈累积应力强度和有效粘滞系数条件,可以使马里亚纳海沟俯冲带在重力作用下弯曲、开裂,或部分向南翻转、变陡。

2-羟基二苯甲酮缩L-异亮氨酸还原Schiff碱的制备

以苯酚和苯甲酰氯为原料,经酯化反应、Fries重排合成得到2-羟基二苯甲酮,再与L-异亮氨酸缩合,形成的Schiff碱经硼氢化钾还原,得到目标化合物2-羟基二苯甲酮缩L-异亮氨酸还原Schiff碱。其组成和结构已由熔点测定、红外光谱和元素分析等方法进行了表征。并探讨了该还原Schiff碱的最佳反应条件为:硼氢化钾用量为1.5当量,反应温度0-5℃,反应时间1 h。