美拉德反应产物丙烯酰胺含量与抗氧化活性的关系

探讨美拉德反应产物抗氧化活性与丙烯酰胺含量之间的关系。以自由基清除率和还原能力吸光值表示抗氧化活性,高效液相色谱(HPLC)检测丙烯酰胺含量,研究不同条件下美拉德反应产物抗氧化活性值与丙烯酰胺含量之间的相关性。结果显示:在10～15 min、120～180℃范围内,丙烯酰胺含量随温度变化趋势与美拉德反应产物自由基清除率的基本一致;美拉德反应产物还原能力在140～160℃范围内达到较大值,基本不随温度的变化而变化。结论:丙烯酰胺生成量和美拉德反应产物的抗氧化活性呈明显的正向关系。     

香辛料抗氧化活性的研究现状

香辛料有很多功能，而抗氧化活性是其重要功能之一。本文论述了30种香辛料的抗氧化活性和一些香辛料对高含DHA鱼油的抗氧化抑制效果，并介绍了从一些香辛料中分离出的具有高活性的抗氧化性物质。     

鲜切西兰花在贮藏过程中自身抗氧化活性的变化

目的研究鲜切西兰花在4℃条件下贮藏14 d内自身抗氧化活性的变化。方法采用DPPH体系、Fenton体系和还原体系研究鲜切西兰花在贮藏期间抗氧化能力的变化。同时还测定了与西兰花抗氧化能力有关的营养成分与酶活性的变化,包括总酚和VC、过氧化氢酶(CAT)、抗坏血酸过氧化物酶(APX)和超氧化物歧化酶(SOD)。结果鲜切西兰花在贮藏期间总抗氧化能力在贮藏前12 d呈逐渐上升状态,之后缓慢降低;清除羟自由基的能力很高,但在贮藏期内呈先缓慢降低后回升的趋势;还原能力在贮藏前10 d呈上升趋势,之后大幅度降低。总酚和APX活性均呈先上升后下降的趋势;VC含量从80 mg/100 g降低到60 mg/100 g,之后变化不大;CAT活性和SOD活性在贮藏前期呈现降低趋势,中期回升,后期又逐渐降低。结论鲜切西兰花的抗氧化能力在8~12 d期间较高。     

Determination of acrylamide content of food products in Korea

Acrylamide (AA) contents of commercial market‐purchased foods and of traditional home‐cooked Korean foods were investigated. The effect of cooking method on AA amount in potatoes was also studied. AA contents of roasted barley and corn ranged from 116 to 449 µg kg^?1 and of chips ranged from 12 to 3241 µg kg^?1, representing a very high variation in AA contents among tested samples. Lower levels of AA were found in wheat flour chips compared to potato chips. AA contents of ramen noodles were below 37 µg kg^?1, whether they contained potato starch or not. The AA contents of Korean home‐cooked oil fried foods increased in the following order: yakwa < whole deep‐fried sea tangle < ground and deep‐fried lotus root < ground and pan‐fried lotus root < French fries < ground and pan‐fried potato. Lotus root and garlic also had the potential to produce AA during cooking. Pre‐treatment such as grinding, boiling, freezing and thawing increased the AA formation in oil‐fried potato. Temperature was more influential than time on AA formation during deep‐oil frying. Removing water‐soluble fractions reduced AA content of cooked potatoes. Copyright © 2006 Society of Chemical Industry     

几种食品添加剂对挤压即食食品丙烯酰胺形成的抑制效果研究

以马铃薯-小麦混合粉为原料,通过在挤压膨化即食食品中,添加不同种类、不同浓度的食品添加剂,研究不同添加剂对产品中丙烯酰胺含量的影响。结果表明:海藻糖、大豆多肽、茶多酚、竹叶提取物、氯化钙等食品添加剂的添加对挤压产品中丙烯酰胺含量的影响显著(p<0.05)。其中当氯化钙添加量达到0.5%时,产品中丙烯酰胺含量比对照减少了80%;大豆多肽添加量达到3%以上或竹叶提取物含量达到0.3%时,产物中丙烯酰胺含量对比对照组减少了50%。     

预处理工艺对黑蒜功能性成分、抗氧化活性影响及相关性研究

分别利用微生物、冷冻和高温高压3种工艺对白蒜进行预处理,发酵制备黑蒜,对黑蒜发酵过程中的色差、褐变程度、总酚、蛋白质、总酸、pH、S-烯丙基-L-半胱氨酸(S-allyl-L-cysteine,SAC)、5-羟甲基糠醛(5-hydroxym-ethylfurfural,5-HMF)等理化指标进行监测,并对羟自由基清除能...     

大蒜精油和姜精油对大豆油的抗氧化活性研究

为了进一步证明大蒜精油和姜油的抗氧化活性,力求为两种精油作为天然多功能食品添加的应用提供一定的理论基础。因此,以用超临界CO2萃取的大蒜油和姜油为主要研究对象,并以精炼大豆油为底物,采用史卡尔(Schaal)法,研究了不同剂量的大蒜精油和姜精油的抗氧化活性,同时将其与用量均为0.02%的TBHQ和维生素E抗氧化能力进行了比较。结果表明,大蒜精油和姜精油对大豆油具有明显的抗氧化效果,并有一定的剂量效应关系,大蒜精油对大豆油的抗氧化能力整体上要明显强于姜精油,并且0.02%大蒜精油的抗氧化性能明显优于0.02%TBHQ和0.02%维生素E,然而实验中姜精油的抗氧化性能均不及0.02%TBHQ和0.02%维生素E。此外,实验研究还发现两种精油添加于油脂中,都会对油脂的颜色和气味产生不同程度的影响。     

生姜不同切割后的抗氧化成分及其活性的变化

对生姜进行不同程度的切割伤害处理(分别切成片状、块状及末状),并在4℃的贮藏温度下于不同的放置时间(0,3,6,12h)测定其抗氧化物质含量,包括黄酮类物质、还原型谷胱甘肽和抗坏血酸含量,并且测定超氧化物歧化酶(SOD)活性,以及测定脂溶性物质抗氧化能力和水溶性物质抗氧化能力。实验结果表明,不同程度的切割伤害处理均使生姜的黄酮类物质含量、还原型谷胱甘肽含量、SOD活性以及水溶性和脂溶性物质的抗氧化能力上升,但切割处理却使VC含量降低,切割伤害程度越大,VC含量下降的速率越快。生姜的脂溶性物质抗氧化能力远远高于水溶性物质的抗氧化能力,总体来说,切割伤害提高了生姜的抗氧化能力,且3种不同的切割伤害处理以伤害程度中等的块状切割最有利于生姜抗氧化能力的提高。      

脱多糖南瓜粉物化特性与抗氧化活性研究

以提取多糖后的南瓜渣为原料制备脱多糖南瓜粉,以南瓜全粉为对照,对比脱多糖南瓜粉与南瓜全粉在物化特性和抗氧化性上的差异。结果表明:与南瓜全粉相比,脱多糖南瓜粉的还原糖含量及其孔隙率均下降明显,戊聚糖和β-胡萝卜素含量略有减少;色泽亮度增加,黄色加深;蛋白质含量虽有所减少,但必需氨基酸所占比例上升,氨基酸组成更加符合FAO/WHO的理想模式;清除DPPH自由基的能力下降。     

Influence of cut type on quality,antioxidant substances and antioxidant activity of fresh-cut broccoli

In order to clarify an efficient and convenient method to increase the antioxidant activity in broccoli, this study intended primarily to elucidate the effect of cutting type on the quality parameters, antioxidant substance contents and antioxidant activity of broccoli using different floret diameters of 10 × 10 cm (CS1), 5 × 5 cm (CS2), 2.5 × 2.5 cm (CS3) and shredded florets (CS4). The results showed that chlorophyll, total soluble solid, vitamin C and reduced glutathione contents of fresh-cut broccoli were decreased obviously during the storage. However, there was a significant influence of cutting type on the enzymatic activities involved in phenolic synthesis and oxidation including phenylalanine ammonia-lyase, cinnamate 4-hydroxylase, and polyphenol oxidase, which contributed to increasing phenolic content by 26.8%, 30.9%, 46.0%, and 51.3% in CS1, CS2, CS3 and CS4, respectively, and further enhanced the antioxidant activity by more than 60% in fresh-cut broccoli. Moreover, the activities of antioxidant-related enzymes, including superoxide dismutase, peroxidase and catalase, were increased significantly in fresh-cut broccoli. In conclusion, the cutting types had no significant effect on quality but clearly influenced the antioxidant substances and activities of broccoli; therefore, this study provided an efficient and convenient method to enhance the potential nutritional value of broccoli.     

生姜多糖类物质的提取及抗氧化活性研究

目的以生姜为原料,采用超声波辅助法和热水浸提法提取生姜多糖类物质并进行抗氧化活性对比研究。方法经单因素试验结合响应面优化设计考察最优提取工艺参数,同时对2种方法提取的生姜多糖抗氧化活性进行对比分析。结果超声波辅助法提取生姜多糖最佳提取条件为:超声温度48℃,超声功率340W,超声时间21 min,液固比50:1(m L/g),在此条件下多糖得率为6.87%;热水浸提法的最佳提取条件为:温度72℃,时间164 min,液固比40:1(m L/g),在此条件下多糖得率为3.13%。抗氧化活性测定结果表明,超声波辅助法和热水浸提法提取生姜多糖的DPPH自由基清除能力的IC_(50)值分别为0.21 mg/m L和0.42 mg/m L,还原能力分别相当于维生素C的3.14%和0.5%,铁离子螯合能力的IC_(50)值分别为2.17 mg/m L和4.18 mg/m L,超声波辅助法提取的生姜多糖的DPPH自由基清除能力、还原力和金属螯合能力分别是热水浸提法提取的生姜多糖的2倍、6倍和1.9倍。结论生姜多糖具有一定的抗氧化活性,本研究可为生姜多糖的提取提供参考。     

姜辣素的超声波辅助提取及其抗氧化活性研究

研究通过单因素及正交试验探讨乙醇体积分数、料液比、超声波处理时间对姜辣素提取效果的影响,确定姜辣素的优化工艺,并探讨了姜辣素提取物对花生油的抗氧化作用,为其进一步开发研究提供参考。结果表明,姜辣素的最佳提取工艺是乙醇体积分数65%vol、功率300W超声提取20min、料液比1∶12（g∶mL）,姜辣素在适宜条件下的提取率达2.78%,该提取物具有抗花生油氧化的作用。     

生姜的抗菌及抗氧化作用的研究进展

文章主要介绍了生姜的化学成分及其提取物的提取方法,重点对生姜的抗菌和抗氧化作用研究进展进行了综述,以期为生姜的综合利用拓展方向。     

热加工对大蒜、洋葱及生姜化学成分和抗氧化能力影响

以大蒜、洋葱及生姜为原料研究其在加热过程中化学成分和抗氧化能力的变化。结果表明:在课题组前期优化得到的最佳工艺参数75℃、85%湿度恒温恒湿箱中热加工8 d后,六种形态大蒜、洋葱及生姜的水分含量都迅速减少、色泽变深,还原糖、总糖、总酸、蛋白质等营养成分含量较热加工前都有升高,多酚含量也增加。热加工后三种辛香蔬菜的抗氧化能力都有不同程度的增加,其中生姜的还原能力、清除羟基自由基能力、清除超氧阴离子自由基能力以及清除DPPH自由基能力增幅最大,分别增加了2.5倍、8.5倍、3.2倍、4.6倍。      

生姜糖蛋白提取工艺优化及抗氧化活性研究

以生姜为原料,在单因素实验基础上采用三元二次回归正交组合设计优化生姜糖蛋白的提取工艺,采用红外光谱初步分析了生姜糖蛋白的结构特征。同时,考察了生姜糖蛋白的抗氧化活性和凝集素芯片的荧光强度。结果表明,生姜糖蛋白的最优提取条件:提取温度为90℃,液固比为35.5∶1,p H为7.5,在此条件下提取3 h,蛋白质得率为2.437 mg/g,糖得率为117.126 mg/g;经分离纯化获得的生姜糖蛋白,采用红外光谱分析表明其存在多糖和蛋白质的特征吸收峰。抗氧化实验与凝集素芯片实验结果表明,生姜糖蛋白在蛋白表面具有糖链结构,且可以螯和金属离子,具备一定的还原能力与重要的生理功能。      

Influence of heating on the polyphenolic content and antioxidant activity of grape seed flour

Abstract: The production of grape seed flour (GSF) from a waste product generated during winemaking, is of interest in product development applications due to its potential health benefits. However, before GSF can used in baking as a source of additional antioxidants, research on its heat stability is required. The overall objective of this study was to assess changes in phenolic content and antioxidant activity of GSF during heating. Merlot GSF was heated at 5 temperatures (120 to 240 °C) for 0 to 90 min. At each time/temperature combination, total phenolic content (TPC), total flavanoid content (TFC), Trolox equivalent antioxidant capacity (TEAC), 2,2 diphenyl‐1‐picrylhydrazyl (DPPH) radical scavenging, and ferric ion reducing antioxidant power (FRAP) of the extracts were determined. Specific polyphenolic compounds, including catechin, gallocatechin, epicatechin, and gallic acid were also measured. Results showed that when Merlot GSF was heated to ≥180 °C, significant decreases in the TPC and antioxidant activity, measured using FRAP, DPPH, and TEAC, were observed. Longer heating times also caused a reduction in antioxidant capability. Catechin and epicatechin content decreased with increasing heating temperature while gallocatechin and gallic acid content increased. Both catechin and epicatechin content had strong positive correlations (r > 0.91) with TPC and TFC, as well with FRAP and TEAC, suggesting that the GSF antioxidant activity is related to the presence of these particular compounds. Overall, while a decrease in antioxidant content was observed during heating, this occurred at higher baking temperatures. Thus GSF may be suitable for use as an ingredient in baked goods to bolster antioxidant content. Practical Application: In order for Merlot grape seed flour (GSF) to be used in baking as a source of additional antioxidant compounds, the impact of heating on the polyphenolic compounds in the GSF needed to be examined. Thermal treatment of Merlot GSF caused significant decreases in the TPC, antioxidant power, and specific polyphenolic compounds when heated ≥180 °C. Thus while antioxidant content decreased with higher heating temperatures, this occurred at higher baking temperatures. Thus, GSF may be suitable for use as an ingredient in baked goods to bolster antioxidant content.     

四种谷物中多酚含量的测定及抗氧化特性研究

对玉米、燕麦、小麦、糙米四种全粒谷物中的多酚物质（可溶性多酚、不溶性多酚、阿魏酸、黄酮等）含量进行测定,并对提取物的抗氧化特性进行研究。结果表明:总酚含量最高的是玉米（49.13±3.39mg/100g）,其次是糙米（23.49±3.37mg/100g）和小麦（18.60±3.52mg/100g）,燕麦中总酚含量最少（13.92±4.56mg/100g）;谷物中多酚主要以结合形式存在（玉米95.54%,糙米90.76%,小麦89.46%,燕麦86.85%）;阿魏酸是主要的多酚物质,且可溶性和不溶性阿魏酸的比例为玉米1∶34、糙米1∶33、小麦1∶17、燕麦1∶5;玉米不溶性提取物清除O2-能力最高（95.01%±2.25%）,该提取物抗油脂氧化能力也最高（POV=34.23±2.61mmol/kg）。      

糖基化修饰产物的抗氧化功能研究进展

蛋白质和糖类是食品中最重要的两类生物大分子,是影响食品质构的主要因素。目前用于蛋白质改性的方法很多,其中糖基化反应就是一种行之有效的改性方法,而修饰后的复合物显示出比各自独立存在更优越的性能,并产生一类具有抗氧化活性的产物,能够起到抗氧化的作用。本文就国内外各种糖基化修饰蛋白的抗氧化性进行了综述,并对其作为新型高分子食品配料具有体外抗氧化活性的保健食品在食品医药领域的应用前景进行了初步探讨。      

裸仁南瓜籽油活性成分分析及抗氧化能力评价

以超临界CO2萃取的裸仁南瓜籽油为研究对象,根据LS/T 3250—2017《南瓜籽油》标准检测其质量指标,运用气相色谱—质谱(GC-MS)联用仪分析脂肪酸和植物甾醇组分,高效液相色谱(HPLC)仪测定角鲨烯含量;以葡萄籽油和亚麻籽油作为对比,研究裸仁南瓜籽油对DPPH、ABTS自由基的清除能力,以评价其抗氧化活性。结果表明,超临界CO2萃取的裸仁南瓜籽油符合LS/T 3250—2017标准,裸仁南瓜籽油主要含有4种不饱和脂肪酸,总含量为74.73%,其中顺式单不饱和脂肪酸和多不饱和脂肪酸含量分别为29.14%,45.54%;富含植物甾醇,β-谷甾醇含量为30.75%,△-7植物甾醇含量达10.77%;角鲨烯含量为5 490μg/g,高达葡萄籽油的80倍,亚麻籽油的279倍;裸仁南瓜籽油具有良好的抗氧化活性,其抗氧化性与油浓度呈正相关,对DPPH自由基的清除能力(IC50为16.14 mg/mL)优于葡萄籽油、亚麻籽油,对ABTS自由基的清除能力(IC50为10.46mg/mL)优于亚麻籽油,裸仁南瓜籽油良好的抗氧化活性可能与其丰富的角鲨烯、植物甾醇和不饱和脂肪酸有关。     

糙米制品抗氧化活性比较研究

研究以糙米为原料,制成糙米饭、糙米线和糙米速食粥3种制品,以精白米饭为对照,分析制品中多酚物质含量、膳食纤维的特性,比较评价其抗氧化活性。结果表明:总酚含量的顺序为:糙米米线(64.05±0.86 mg/100 g)糙米速食粥(63.95±2.02 mg/100 g)糙米饭(50.70±0.02 mg/100 g)白米饭(20.27±0.46 mg/100 g);总黄酮含量顺序为:糙米速食粥(736.50±26.05 mg/100 g)糙米米线(642.27±66.94 mg/100 g)糙米饭(581.17±21.91 mg/100 g)白米饭(186.81±14.12 mg/100 g)。3种糙米制品中总抗氧化能力差异不显著且均高于白米米饭,清除DPPH、ABTS+能力顺序:糙米速食粥糙米线糙米饭白米饭(P0.05)。制品总酚和黄酮含量与自由基的清除力具备显著的相关性(P0.01);游离型总酚和总黄酮含量与其总抗氧化活性具有良好的相关性,相关系数分别为0.904和0.824。糙米线和速食粥的膳食纤维对脂肪酸的吸附力是米饭的2倍左右。糙米制品膳食纤维抗氧活性均高于白米饭;速食粥清除DPPH的能力是米线的2倍多,是米饭的4倍多;速食粥和米线对ABTS+清除力是米饭的3~4倍。糙米速食粥、糙米米线与米饭相比,酚类物质含量较高、膳食纤维具有较强的油脂吸附力和清除自由基的能力。