肉制品中亚硝酸盐替代的研究现状及作用机制

亚硝酸盐在肉制品中应用广泛，具有护色、抗氧化、改良风味、抑菌等多种作用。然而，亚硝酸盐在体内代谢后易形成致畸致癌物——N-亚硝胺，危害人体健康。因此，亚硝酸盐替代物的开发一直是肉制品领域的研究热点。文章对目前的两大类亚硝酸盐替代物(天然植物提取物和微生物)的研究分别进行综述，并对其作用机制进行剖析，以期为更健康绿色的新型肉制品生产提供借鉴。     

绿茶、橘皮、大豆中酚类物质体外消化前后稳定性及抗氧化活性的研究

本研究以富含3类代表性酚类化合物（黄烷醇、黄烷酮和异黄酮）的3种食物（绿茶、橘皮、大豆）作为原料,模拟其在人体口胃肠中的体外消化过程。采用高效液相色谱-二极管阵列检测器/电喷雾-四极杆-飞行时间串联质谱检测器（HPLC-DAD/ESI-Q-TOF-MS）检测体外消化前后酚类化合物的种类及含量变化,同时测定不同消化阶段总酚含量（TPC）、总黄酮含量（TFC）以及抗氧化活性（DPPH、ABTS、FRAP、ORAC）的变化。结果表明,绿茶提取物中检测出4种酚类化合物（表没食子儿茶素、(+)-儿茶素、表没食子儿茶素没食子酸酯和表儿茶素没食子酸酯）,大豆提取物中检测出4种酚类化合物（大豆苷、染料木苷、大豆苷元和染料木素）,橘皮提取物中检测出2种酚类化合物（柚皮苷和橙皮苷）;三种食物提取物中,经过体外消化后,绿茶提取物中的酚类化合物最不稳定,除(+)-儿茶素外,其余3种酚类物质几乎降解完全,损失率均达95%以上。绿茶、橘皮、大豆提取物的TPC在胃消化阶段显著升高（P<0.05）,在肠消化阶段显著降低（P<0.05）。绿茶提取物TFC在口腔和胃消化阶段显著升高（P<0.05）,在肠消化阶段显著降低（P<0.05）。橘皮、大豆提取物TFC与TPC变化趋势一致。绿茶提取物的四种抗氧化活性经胃肠消化后呈先升高再降低的趋势。大豆提取液体外消化前后ABTS、FRAP抗氧化活性在口腔阶段显著降低（P<0.05）,DPPH、ORAC抗氧化活性在口腔、胃消化阶段显著升高（P<0.05）,在肠消化阶段显著降低（P<0.05）。橘皮提取液ORAC抗氧化活性在肠消化阶段显著升高（P<0.05）,ABTS、FRAP抗氧化活性在体外消化阶段均表现出和总酚含量变化一致的趋势。     

聚葡萄糖的特性及其在肉制品中的应用

聚葡萄糖是一种水溶性膳食纤维,有很好的理化性质和生理功能。本文重点阐述了聚葡萄糖的特性及其在肉制品中的应用和功能性肉制品的发展趋势。聚葡萄糖和肉制品的结合可以赋予肉制品更多的功能特性,对人体有更健康的益处。     

静电纺丝技术包埋天然酚类化合物研究进展

天然酚类化合物因其对人体健康具有众多益处,近年来在食品、营养学和医药等领域得到了广泛的关注。然而,酚类化合物较差的溶解性、稳定性和生物利用度等严重地限制了其应用。如何有效地保护和运载这些酚类化合物并保持其生物活性成为研究的热点问题。静电纺丝是一种易于操作且成本低廉的纳米级纤维制备技术,所制备的纳米纤维可作为纳米载体对生物活性物质进行包埋和控制释放,因此可作为包埋酚类化合物的一种有效方法。本文概述了静电纺丝技术的基本原理、类型、影响参数、常用的聚合物基质和优势,对静电纺丝技术包埋天然酚类化合物的相关研究进行了综述,最后展望了其在食品工业的应用前景,以期为静电纺丝技术在食品领域应用提供一定的理论指导。     

水产品中常见酚类化合物检测方法研究进展

作为当前被广泛关注的水体污染物之一,酚类化合物分布广泛、种类繁多、危害性高。酚类化合物不仅可通过生活饮用水直接进入人体,也可经水体及水体微生物转移到水产品中,在水产品中富集,并通过食物链对人体造成潜在的危害,因此对水产品中酚类化合物的研究具有极其重要的意义。本研究综合调研了水产品中常见酚类化合物的研究现状,重点聚焦了常见酚类化合物相关检测技术进展,以期探寻便捷、高效、灵敏的酚类化合物检测技术,为研究和制定水产品中酚类化合物检测方法标准提供依据。     

体外结肠发酵对青稞膳食纤维中酚类化合物的含量及抗氧化活性的影响

以青稞中的可溶性膳食纤维(soluble dietary fiber,SDF)和不可溶性膳食纤维(insoluble dietary fiber,IDF)为原料,通过体外结肠发酵,测定不同时间点酚类化合物的含量和抗氧化活性,并利用高效液相色谱法对发酵液中的酚类化合物进行定性和定量。结果表明:在体外结肠发酵48 h过程中,随着发酵时间的延长,IDF中酚类化合物含量呈逐渐升高趋势,SDF中酚类化合物含量呈先升高后下降趋势,在结肠发酵第30小时,酚类化合物含量达到最高,为(50.62±2.45)μmol/g;IDF和SDF中酚类化合物的抗氧化活性变化趋势与酚类化合物含量变化相似;青稞膳食纤维经体外结肠发酵后,发酵液中酚类化合物分为羟基苯甲酸、羟基肉桂酸和类黄酮,包括18种酚类化合物。在结肠发酵过程中,IDF和SDF中阿魏酸含量均呈先升高后下降趋势,IDF在发酵第24小时含量最高;SDF在发酵第5小时含量最高。结果表明,青稞膳食纤维可作为多酚的传递物质,在结肠发酵过程中缓慢释放多酚化合物,能够提高多酚含量和抗氧化活性,促进人体健康。     

体外消化和结肠发酵对蜂花粉酚类化合物及抗氧化活性的影响

蜂花粉富含酚类化合物,具有抗氧化、抑菌、抗炎等功效,因此蜂花粉酚类化合物的吸收和利用与人体的健康密切相关.该文以油菜蜂花粉、五味子蜂花粉、茶花粉为原料,通过体外胃肠消化和结肠发酵,对比了3种蜂花粉在不同消化阶段以及发酵时间总酚、总黄酮的含量和抗氧化活性的变化规律,并进一步分析其生物有效性.结果显示,3种蜂花粉经体外胃肠...     

传统肉制品加工过程中亚硝酸盐的控制技术

亚硝酸盐因其具有良好的发色、抗氧化、抑菌等作用而被广泛应用于肉制品加工中,然而亚硝酸盐在肉制品中能够形成致癌性的亚硝胺类物质,致使肉制品的食用安全性降低。随着人们健康意识越来越强,传统肉制品加工过程中亚硝酸含量问题也被高度重视。目前,许多学者开始研究低亚硝酸盐肉制品的加工方式、肉制品中亚硝酸盐的控制方法等。在此研究领域,东北农业大学食品学院的孔保华教授取得了丰硕成果,本刊记者就传统肉制品加工过程中亚硝酸盐的控制技术对孔保华教授进行了专访。     

亚硝酸盐在肉制品加工中的应用研究

亚硝酸盐是一种常见的食品添加剂,因其具有良好的发色、抗氧化、抑菌等作用而被广泛应用于肉制品加工中。但如果食品中亚硝酸盐含量过多,会对人体造成一定的危害。通过综合分析亚硝酸盐的特性及其在肉制品加工中的作用、存在的安全性问题,探寻更好地减少或替代亚硝酸盐使用的方法,以期为安全肉制品的生产提供理论依据。     

天然酚类化合物的抑菌作用及在肉与肉制品中的应用研究进展

氧化和微生物腐败是影响肉与肉制品品质和货架期的主要原因。从植物中提取的酚类化合物具有抗氧化和抑菌活性,但其抑菌机制尚不完全明确,同时缺乏较为系统、深入的总结。本文基于天然酚类化合物的分类和抑菌活性差异,从细胞壁、细胞膜、生物膜和蛋白质的合成等方面分析总结酚类化合物可能的抑菌机制及其在肉类工业中的应用情况,以期为研究天然酚类化合物的抑菌机制及其在肉类生产加工中的应用提供理论基础。     

茶多酚在肉制品保鲜中的应用研究进展

肉制品营养丰富、味道鲜美,一直是人们餐桌上的佳肴,但受微生物、物理和酶的作用极易腐败变质,限制了其货架期和流通半径。茶多酚是一类从茶叶中提取、具有多个酚羟基的化合物,因具有较强的抗氧化性被广泛应用于肉制品贮藏和保鲜中,并取得较好的效果。本文介绍了茶多酚的结构及性质,综述了茶多酚抗氧化及抗菌机理,分析了茶多酚在多种肉制品保鲜中的应用现状,对茶多酚的应用前景进行展望。     

White and Green Teas (Camellia sinensis var. sinensis): Variation in Phenolic,Methylxanthine, and Antioxidant Profiles

Abstract: Recent investigations have associated white teas with anti-carcinogenic, immune-boosting, and antioxidative properties that may impact human health in a manner comparable to green teas. An in-depth chemical analysis of white tea types was conducted to quantify polyphenols and antioxidant potential of 8 commercially available white teas, and compare them to green tea. Extraction and HPLC protocols were optimized and validated for the quantification of 9 phenolic and 3 methylxanthine compounds to examine inter- and intra-variation in white and green tea types and subtypes. A sampling strategy was devised to assess various subtypes procured from different commercial sources. Variation in antioxidant activity and total phenolic content (TPC) of both tea types was further assessed by the 1-1-diphenyl-2-picrylhydrazyl (DPPH) and Folin–Ciocalteau (F–C) assays, respectively. Total catechin content (TCC) for white teas ranged widely from 14.40 to 369.60 mg/g of dry plant material for water extracts and 47.16 to 163.94 mg/g for methanol extracts. TCC for green teas also ranged more than 10-fold, from 21.38 to 228.20 mg/g of dry plant material for water extracts and 32.23 to 141.24 mg/g for methanol extracts. These findings indicate that statements suggesting a hierarchical order of catechin content among tea types are inconclusive and should be made with attention to a sampling strategy that specifies the tea subtype and its source. Certain white teas have comparable quantities of total catechins to some green teas, but lesser antioxidant capacity, suggesting that white teas have fewer non-catechin antioxidants present. Practical Application: In this investigation white and green teas were extracted in ways that mimic common tea preparation practices, and their chemical profiles were determined using validated analytical chemistry methods. The results suggest certain green and white tea types have comparable levels of catechins with potential health promoting qualities. Specifically, the polyphenolic content of green teas was found to be similar to certain white tea varieties, which makes the latter tea type a potential substitute for people interested in consuming polyphenols for health reasons. Moreover, this study is among the first to demonstrate the effect subtype sampling, source of procurement, cultivation, and processing practices have on the final white tea product, as such analysis has previously been mostly carried out on green teas.     

红茶抗氧化活性有效成分及其作用机制研究进展

随着生命科学领域研究的深入,抗氧化的重要性日益被人们广泛认知.红茶作为一种广受人们喜爱的健康饮品,富含茶多酚、茶色素等多种抗氧化活性成分,可以通过直接消除自由基、络合金属离子、调节生物酶系的活性等途径起到抗氧化作用,对于人体来说是一种有价值的抗氧化剂来源.文章通过查阅近十几年来红茶抗氧化相关文献,对红茶抗氧化活性有效成...     

Polyphenolic compounds as functional ingredients in cheese

A functional cheese product containing polyphenolic compounds was developed, and the polyphenolic retention efficiency and antioxidant property of the product evaluated. Single phenolic compounds, including catechin, epigallocatechin gallate (EGCG), tannic acid, homovanillic acid, hesperetin and flavones, and natural crude compounds, such as grape extract, green tea extract, and dehydrated cranberry powder, were added as functional ingredients to the prepared cheese. They evidenced different levels of retention in the cheese curds which varied widely in terms of their effects on gel-formation behaviours, depending on their molecular properties and their hydrophobicity was particularly relevant. Cheese curds with polyphenolic compounds at a concentration of 0.5 mg/mL showed effective free radical-scavenging activity. The nutritional value of cheese product was improved by adding bioactive phenolic compounds to the cheese curd. These results suggest that we may apply this approach to other dairy products for better quality and functionality of the products.     

Screening of the antioxidant properties and polyphenol composition of aromatised green tea infusions

BACKGROUND: Aromatised green teas are widely sold and popular owing to their fragrance. In this study the antioxidant activity of six commercial green tea infusions was assessed by three complementary assays. RESULTS: In order to evaluate the tea infusions as antioxidant sources, their phenolic content (Folin‐Ciocalteu assay), cupric ion‐reducing antioxidant capacity (CUPRAC) and 2,2‐diphenyl‐1‐picryhydrazyl (DPPH) radical‐scavenging ability were determined. Their content of polyphenols was also determined by high‐performance liquid chromatography/mass spectrometry (HPLC/MS) in negative electrospray ionisation mode. Some teas with citrus aroma, besides having a relatively high content of catechins, also contain other phenolic compounds such as naringin and hesperidin. The three assays used to evaluate the antioxidant capacity of the tea infusions gave different rank orders. Therefore an antioxidant index was calculated for better correlation of the results, and its highest value was obtained for Clear Green Mint tea infusion. CONCLUSION: The studied teas, besides having a relatively high content of catechins, also contain naringin and hesperidin, which are not present in ‘pure’ green tea. It is important to run multiple assays to get a better estimate of the antioxidant capacity of a given sample. Copyright © 2012 Society of Chemical Industry     

微波加热对食品中酚类物质的含量及抗氧化活性的影响

酚类物质具有预防疾病和抗氧化等功效,在食品中应用广泛,但是食品烹调手段可能会影响酚类物质的组成和特性,微波加热是新兴的食品烹调加工方法,本文对微波引起食品中酚类物质和食品抗氧化活性的影响进行了综述,展望了酚类提取物的应用情况。      

Green Tea Polyphenolic Compounds and Human Health

Polyphenols are a structurally diverse group of compounds that occur widely throughout the plant kingdom. Polyphenolic compounds are ubiquitous in all plant organs and are, therefore, an integral part of the human diet. Recent interest in food phenolics has increased greatly because of the antioxidant and free radical-scavenging abilities associated with some phenolics and their potential effects on human health. Most of the polyphenols in green tea are commonly known as catechins. The regular consumption of green tea is related to benefits in some diseases as atherosclerosis and cancer. Although consumption of dietary polyphenols such as flavonoids has been suggested to have beneficial biological effects, there are considerable evidences to suggest that such compounds are not without risk of adverse effects.     

Antioxidative and Anti-Glycation Activity of Buckwheat Hull Tea Infusion

The utilization of buckwheat hull for the preparation of buckwheat hull tea was addressed in this study. The total phenolics content, flavonoids profile, antioxidant capacity, and anti-glycation activity of buckwheat hull tea were compared to those of green tea. The buckwheat hull contained rutin, quercetin, and C-glucoflavones; however, the total phenolic content was significantly lower in comparison to green tea leaves. Rutin and vitexin were the main flavonoids found in buckwheat hull tea. The buckwheat hull tea showed lower antioxidant capacity and inhibitory activity against the formation of fluorescent advanced glycation end products as compared to green tea.