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阿霍烯是一种高生物活性硫化物,具有预防心血管疾病等功能。在新鲜大蒜中阿霍烯的含量极少,且稳定性差。本文用新鲜大蒜中的内源酶将其加工成富含阿霍烯的"黑大蒜"制品,调查国内外12种大蒜在加工中蒜氨酸、大蒜辣素和阿霍烯含量的变化,分析各成分含量之间的定量关系,以揭示阿霍烯的产生过程。试验结果表明,蒜氨酸含量在加工中逐渐减少,并趋于平衡;大蒜辣素含量在加工前、后都较低,而加工第2天出现最大值(即最大生成量);阿霍烯含量在加工20d内随时间呈线性增加。黑大蒜制品的阿霍烯含量随大蒜辣素含量的增加呈线性增加,大蒜辣素含量随新鲜大蒜中蒜氨酸含量的增加呈线性增加,充分说明蒜氨酸经过大蒜辣素向阿霍烯的转化过程。当新鲜大蒜中蒜氨酸含量为5.94%时,黑大蒜制品中阿霍烯的含量可达新鲜大蒜的17.5倍。 相似文献
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大蒜是一种药食同源的食物。介绍了大蒜中功能性成分,包括大蒜新素、大蒜辣素、蒜氨酸、蒜酶、超氧化物歧化酶、大蒜多糖、有机硒、有机锗,概述了大蒜具有的保健功能,指出大蒜开发利用的现状及存在问题。 相似文献
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丙酮酸差量法测定大蒜中大蒜辣素含量方法的建立 总被引:1,自引:0,他引:1
《食品与发酵工业》2015,(11):148-151
通过测定经酶促反应后大蒜鳞茎中的丙酮酸含量,以灭酶组大蒜鳞茎中丙酮酸含量为本底,应用丙酮酸差量法计算得出大蒜鳞茎中大蒜辣素含量,并对测定条件进行优化。结果表明:大蒜本底灭酶条件为100℃水浴加热30 min,酶促反应温度为30℃,酶促反应时间为10 min,在520 nm下测定吸光度值,丙酮酸含量浓度在10~50μg/m L内与吸光度呈良好的线性关系,大蒜辣素测定精密度相对标准偏差为0.88%,重现性相对标准偏差为1.05%。该方法操作简单、稳定、重复性好,对于测定大蒜中大蒜辣素切实可行。 相似文献
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不同干燥方法对大蒜的蒜氨酸酶活力的影响 总被引:7,自引:0,他引:7
主要研究了冷冻干燥法以及微波真空干燥与真空干燥联合干燥法这两种不同的干燥方法对大蒜的蒜氨酸酶活力的影响,提取了两种干燥方法得到的干燥大蒜中的蒜氨酸酶,并以合成的蒜氨酸为底物进行了蒜氨酸酶活力的测定。结果表明,新鲜大蒜和冷冻干燥大蒜中蒜氨酸酶的最适温度为40℃,微波真空干燥与真空干燥联合干燥大蒜中酶的最适温度为45℃,新鲜大蒜和两种不同干燥方法干燥的大蒜片中,蒜氨酸酶的最适pH均为6.5。冷冻干燥大蒜及微波真空干燥与真空干燥联合干燥大蒜的酶活保留率分别为96%和87.8%,结果表明,冷冻干燥大蒜的质量略优于微波真空干燥与真空干燥联合干燥法干燥的大蒜。但由于冷冻干燥能耗大,因此微波真空干燥与真空干燥联合干燥法仍是一种生产优质大蒜片的干燥方法。 相似文献
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泰安大蒜与金乡大蒜挥发性风味物质成分分析 总被引:1,自引:0,他引:1
采用自动化静态顶空与气质联用的方法分析对比金乡大蒜与泰安大蒜的挥发性成分,通过GC-MS分析和NIST质谱库计算机检索,对样品进行定性分析,并采用面积归一化法进行定量分析。检测结果表明,不同产地的大蒜中的挥发性风味物质种类略有差别,金乡大蒜中含硫化合物总量高于泰安大蒜,并且,新鲜大蒜含硫化合物含量高于贮藏大蒜,存在显著差异。金乡大蒜和泰安大蒜检出的风味物质种类略有差别,地域性差别对大蒜风味物质种类影响不大,但是,在大蒜风味物质中起决定性作用的1,3-二噻烷、烯丙基三硫化物、烯丙基二硫化物以及而烯丙基四硫醚,在含量上金乡大蒜明显高于泰安大蒜。同时,研究表明,静态顶空与气质联用能够快速、简便、高效、准确地对大蒜中的挥发性风味物质进行组分分析以及鉴定。 相似文献
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Low-frequency and low-intensity ultrasound accelerates alliinase-catalysed synthesis of allicin in freshly crushed garlic 总被引:1,自引:0,他引:1
BACKGROUND: The well‐known chemically and therapeutically active compound allicin is formed in crushed garlic by the interaction of alliin with alliinase. In this study, low‐frequency and low‐intensity ultrasound was employed to accelerate the alliinase‐catalysed synthesis of allicin in freshly crushed garlic. RESULTS: The optimal conditions for improvement of the alliinase‐catalysed synthesis of allicin in freshly crushed garlic were found to be as follows: ultrasound intensity 0.4 W cm?2, ultrasound frequency 50 kHz, enzymatic reaction temperature 35 °C and reaction time 30 min. Under these conditions the yield of allicin was increased by about 25.2% compared with the control without ultrasound. Alliinase in the freshly crushed garlic was purified by ammonium sulfate precipitation and gel filtration on a Sephacryl S‐200 column. The employed ultrasound increased the activity of the purified alliinase by about 42.8%, did not affect the enzyme's temperature optimum and improved its thermal stability. CONCLUSION: The results of this study indicated that the activity of alliinase in freshly crushed garlic might be enhanced by low‐frequency and low‐intensity ultrasound, thereby accelerating the alliinase‐catalysed conversion of alliin in garlic to allicin. Copyright © 2011 Society of Chemical Industry 相似文献
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大蒜中的主要有效成分是大蒜素,它具有强烈的刺激性臭味,但鲜蒜中并不含大蒜素,而含有它的前体物质——大蒜氨酸,它以稳定无臭的形式存在于大蒜中。当大蒜受到冲击(切片或捣碎),蒜酶接触空气被活化,大蒜氨酸转化为大蒜素。根据这一机理,采用不同的反应务件进行实验,开发出脱臭蒜素琼脂糖和脱臭速冻大蒜。 相似文献
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ABSTRACT: Heated (121 °C) garlic extract in which alliinase was inactivated before crushing exhibited complete bacteriostatic activity at 15% against Staphylococcus aureus. Garlic heated for 45 min showed the highest antibacterial activity and the relative peak areas of 4-heptenal, methyl allyl disulfide, diallyl disulfide, 2-vinyl-4H-1,3-dithiin, and diallyl trisulfide (DATS) were highest at 45 min of heating. Other than 4-heptenal, all these compounds are known to possess different degrees of antibacterial activity. DATS was thought to be the primary antibacterial compound in heated garlic extract. It was tentatively concluded that antibacterial compounds were formed from alliin unreacted by alliinase by marked heating. Diallyl compounds with more than three sulfur atoms and the oxidized form of allicin were not detected. 相似文献
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Allinase, which catalyzes the conversion of alliin to allicin, the principal component of potential medicinal value in garlic, is a thermo-labile enzyme. The potential for allicin formation is determined by the quantity of allinase that remains active after the process of preserving garlic by drying. The kinetics of enzymatic activity loss during drying by temperature cycling or by constant temperature were evaluated and compared. Allicin-forming potential was 91% preserved by temperature cycling from 40 to 60 °C. It was found that sugars present in the garlic and the high molecular mass of the enzyme were responsible for protection against degradation at high drying temperatures. Preservation of the enzymatic activity under cyclical conditions occurred mainly with exposure to low temperatures for drying periods longer than those of constant drying conditions. 相似文献
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建立了大蒜中大蒜素和蒜氨酸含量测定的HPLC法。结果表明:蒜氨酸的测定条件为,YMC-PackODS-A C18(25 cm×4.6 mm)色谱柱,流动相为20%甲醇,流速0.7 mL/min,检测波长214 nm;大蒜素的测定条件为,YMC-Pack ODS-A C18(25 cm×4.6 mm)色谱柱,流动相为85%甲醇,流速0.8 mL/min,检测波长214 nm;蒜氨酸和大蒜素的平均回收率分别为,89.9%±1.6%和87.2%±1.3%,精密度(RSD)分别为1.02%和1.46%;大蒜中蒜氨酸和大蒜素的含量分别为,1.67%和0.93%。 相似文献
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硫代亚磺酸酯参与大蒜绿变作用机理初探 总被引:2,自引:0,他引:2
对新蒜采取三种不同贮藏温度处理,对大蒜中硫代亚磺酸酯含量和蒜泥滤液吸光值进行了多点监测,研究硫代亚磺酸酯与大蒜绿变能力之间的关系。结果表明,大蒜绿变能力同硫代亚磺酸酯含量呈正相关关系,由此推测硫代亚磺酸酯是参与大蒜绿变反应重要物质,其含量决定了大蒜的绿变能力。同时研究乙酸浸泡期间大蒜硫代亚磺酸酯含量的变化,分析硫代亚磺酸酯与大蒜绿变程度之间的关系。试验得出,硫代亚磺酸酯含量与大蒜绿变程度的呈线性负相关关系,推测在大蒜中前体物质——蒜氨酸含量一定的条件下,绿色素形成的越多,作为反应中间体的硫代亚磺酸酯参与转化越多,最终表现在它的含量随大蒜绿变程度增加而降低。这就进一步说明硫代亚磺酸酯参与了大蒜绿变反应。大蒜在低温贮藏过程中,第15d之后蒜素含量有很好的升高趋势,这为提高大蒜中蒜素含量的研究建立了理论依据,为其提取加工提供了生产建议。 相似文献