益生菌发酵对苹果浆理化性质、抗氧化活性及挥发性风味的影响

目的 探究益生菌发酵对苹果浆理化性质、抗氧化活性及挥发性风味物质的影响。方法 测定苹果浆发酵过程中活菌数、pH、总酸、总糖、还原糖、总酚、黄酮、1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl, DPPH)自由基清除能力、铁离子还原能力(ferric reducing antioxidant power, FRAP)和2,2’-联氮-二(3-乙基-苯并噻唑啉-6-磺酸)二铵盐[2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonicacid)ammoniumsalt,ABTS]阳离子自由基清除能力,同时比较了发酵前后挥发性风味物质的变化。结果 发酵体系中活菌数、总酚、黄酮在发酵第3d时达到最大值,分别较发酵前提高了12.63%、17.63%和22.06%;FRAP与ABTS阳离子自由基清除能力在发酵第4d达到最大值,分别较发酵前提高了42.47%和10.45%;可滴定酸含量与DPPH自由基清除能力随着发酵时间的延长逐渐增加,发酵第7 d时,分别升高了126.34%和26.32%; pH、总糖、还原糖含量较...     

Application of amaranth protein isolate and hydrolysate on a reduced salt fish restructured product: antioxidant properties,textural and microbiological effects

This work evaluates amaranth protein ingredients [isolate (I) and alcalase‐hydrolysate (H)] acting as antioxidants and binders in restructured fish products. Gel products were obtained after thermal treatment (40 °C, 30 min; 90 °C, 30 min) of different formulations from fish muscle pastes, where salt (2%) was partially or totally replaced by I or H. Antioxidant activity was assessed by conjugated dienes and thiobarbituric acid‐reactive substances (TBARs) measurements during the chilled storage. Textural properties, water‐holding capacity, colour and microbiological quality were evaluated. Reduced‐salt content products containing 2% w/w of I or H partially inhibited lipid oxidation especially at the level of the decomposition of hydroperoxides into secondary products, due to about 50% and 60% of inhibition of TBARs, respectively, was registered. Also, these products showed acceptable microbiological quality and technological characteristics with only minimal changes in properties as gel hardness and colour parameters compared with control products (2% w/w salt).     

无糖藜麦发酵乳的物化特性及抗氧化活性

目的：开发有益于身体健康的无糖风味发酵乳。方法：在复原乳中添加藜麦浆,以木糖醇替代蔗糖经发酵后得无糖藜麦发酵乳,以酸度、黏度、持水力等物化特性及体外抗氧化为评价指标,探究藜麦浆对无糖发酵乳的影响。结果：添加藜麦浆的发酵乳pH高于普通发酵乳,酸度、黏度、持水力则略低于普通发酵乳,且无糖藜麦发酵乳的DPPH自由基清除率（86.23%）、ABTS自由基清除率（71.32%）、羟基自由基清除率（63.27%）、Fe³⁺还原能力（0.48 mmol/L）均高于普通发酵乳。结论：添加木糖醇和藜麦浆会改变发酵乳的物化性质,同时提高发酵乳的抗氧化活性。     

蛹虫草固态发酵豆渣的功能性成分与抗氧化活性

目的:用蛹虫草固态发酵豆渣,测定豆渣发酵前后功能性成分含量及抗氧化能力的变化。方法:蛹虫草CM-1固态发酵豆渣7 d,测定发酵前后豆渣水提物中虫草素、总酚和多糖的含量,以及DPPH自由基清除力、还原力、ABTS自由基清除能力、铁离子还原力（FRAP）的变化,并用皮尔森相关性分析以及主成分分析研究了虫草素、总酚、多糖含量与抗氧化指标之间的关系。结果:豆渣经蛹虫草CM-1固态发酵,水提物中多糖、虫草素和总酚含量分别是（236.16±39.91）、（1.88±0.04）μg/mg和（11.94±0.33）μg GAE/mg,多糖、总酚含量分别是发酵前的1.42倍和2.15倍。豆渣经过发酵,在提取物浓度为6 mg/m L时,DPPH自由基清除力由24.63%提高到72.4%,还原力由0.11提高到0.38,ABTS自由基清除能力由76.76%提高至88.71%,FRAP由39.08μmol/L提高至269.55μmol/L。主成分分析和相关性分析表明,抗氧化指标与虫草素、总酚、多糖含量具有非常显著的相关性（p<0.01）。结论:用蛹虫草发酵豆渣可以提高豆渣的功能性成分和抗氧化能力,发酵豆渣有望开发成为功能性食品基料及抗氧化食品。      

The influence of douchi starter cultures on the composition of extractive components, microbiological activity, and sensory properties of fermented fish pastes

Three experiments were conducted to test the hypothesis that douchi cultures could serve as a potential starter for enhancing the quality attributes of fermented silver carp meat. In experiment 1, an active, prefermented douchi culture was incorporated into a fish paste to aid in the fish fermentation (30 d) and facilitate biochemical production of extractive flavor components (PRF). In experiment 2, a fully fermented (30 d) douchi was added to a fish paste and the mixture was fermented for 30 d (PSF). In experiment 3, a fish paste without the douchi culture was fermented for 30 d (CF). Total extracted free amino acids increased by 68.0, 68.6, and 78.8% (P < 0.05) from their initial levels to 2930, 2422, and 1573 mg/mL after 30 d of fermentation for PRF, PSF, and CF fish pastes, respectively, of which, glutamic acid, aspartic acid, alanine, lysine, and leucine were the major amino acids (>100 mg/mL). The concentrations of both formaldehyde-reactive nitrogen and ammonia nitrogen extractives increased significantly (P < 0.05) during fermentation, following the order of PRF > PSF > CF. Low amounts of biogenic amines (<25 ppm) were produced in all samples. Sensory panel evaluation showed that PRF fish pastes had desirable aroma and taste. The douchi-inoculated fermentation could be a novel technique for expanding the utilization, consumption, and the economic values of silver carp meats. Practical Application: Douchi, a fermented soybean product, is a traditional food flavoring ingredient commonly used in China, Japan, and other Asian countries. It is also used in many Chinese cuisines in the United States. On the other hand, fermented seafood made from freshwater fish such as silver carp is known to contain bioactive components believed to promote health. The findings from the present study indicated that douchi as a novel starter can be used to produce fermented silver carp fish pastes with excellent flavor and consumer acceptability. The results may be applicable to other fish species to produce similar fermentation products.     

酸浆水中3种菌株的产酸能力及抗氧化活性

为了获得优质的豆腐凝固剂,应用从自然发酵的酸浆水中分离的3个菌株(解淀粉杆菌L5、L6以及阿米塞毕赤氏酵母Y),分别进行单菌、双菌和三菌发酵试验,研究其产酸能力和抗氧化活性。结果表明:两个解淀粉乳杆菌菌株均可在豆腐黄浆水生长产酸,其中菌株L6发酵豆腐黄浆水产酸能力更强,35℃发酵60 h后,酸度达到65.11oT,而3个菌株进行组合发酵时也有较强的产酸能力,在发酵60 h后,酸度也达到65.44oT。经过解淀粉乳杆菌L6发酵后,酸浆水还原Fe3+的能力和清除DPPH自由基的能力略有增加,螯合Fe2+的能力显著增强,在发酵48 h时达到54.45%;与L6不同,解淀粉乳杆菌L5发酵制备的酸浆水螯合Fe2+的能力随着发酵时间延长而明显下降;阿米塞毕赤氏酵母Y发酵制备的酸浆水具有良好的还原Fe3+的能力、清除DPPH自由基的能力以及螯合Fe2+的能力;当3个菌株组合发酵时,其产酸能力以及酸浆水还原Fe3+的能力、清除DPPH自由基的能力和螯合Fe2+的能力均比L6+Y双菌株发酵制备的酸浆水强。综合得出,在发酵豆腐黄浆水产酸和抗氧化能力方面,单菌株L6最优,组合发酵时L5+L6+Y为最优。     

连翘叶发酵型饮料的研制及抗氧化活性研究

以连翘叶、白砂糖、阿拉伯胶为主要原料,制备连翘叶发酵型饮料。在单因素试验基础上,以感官评分为评价指标,采用二次通用旋转组合试验优化其发酵工艺,并考察其对1,1-二苯基-2-三硝基苯肼(DPPH)、2,2’-联氮-双-3-乙基苯并噻唑啉-6-磺酸(ABTS)自由基清除能力及还原力。结果表明,连翘叶发酵型饮料的最佳发酵工艺条件为白砂糖添加量5%,复合菌种(克鲁维毕赤酵母∶植物乳杆菌=1∶1)接种量0.04%,连翘叶粉添加量2.0%,阿拉伯胶添加量0.6%,发酵时间18 h。在此优化条件下,连翘叶发酵型饮料感官评分为(86.53±1.03)分,色香味俱佳,口感酸甜,无明显苦味,理化与微生物指标均符合相关国家标准。连翘叶发酵型饮料的DPPH自由基清除率、ABTS自由基清除率及还原力(OD_{700 nm}值)分别为(90.57±2.63)%、(79.85±1.74)%、(0.736±0.04),表明其具有良好的抗氧化性。     

3种不同酵母发酵黄精酒的抗氧化活性及风味物质分析

目的 探究3种酵母发酵黄精(Polygonatum cyrtonema)酒的抗氧化活性及其风味特征。方法 借助紫外分光光度法、电子舌、顶空固相微萃取-气相色谱-质谱法(headspace solid phase microextraction-gas chromatography-mass spectrometry, HS-SPME-GC-MS)及感官评价法多源信息综合分析BRG、D254、DV10 3种商业酵母发酵黄精酒的理化指标、总酚、总黄酮、抗氧化活性及滋味和挥发性香气成分。结果 酵母发酵能够提升黄精酒皂苷、总酚、总黄酮的含量及抗氧化活性。不同酵母发酵黄精酒的理化指标存在显著差异, DV10发酵的黄精酒酒精度、总黄酮含量, 总糖、总酸含量相对较低。电子舌系统测定结果表明3种黄精酒在涩味、苦味回味、鲜味、丰富度、咸味、酸味和苦味上存在差异, DV10黄精酒滋味更为协调。3种酵母发酵的黄精酒共计检测出51种挥发性物质, BRG、DV10和D254分别为36、31和22种。DV10菌株发酵的黄精酒酯类物质含量最高, 气味活度值(odor activity value, OAV)>500的香气成分有6种, 分别为丁酸乙酯、乙酸异戊酯、正己酸乙酯、辛酸乙酯、癸酸乙酯、异戊醇, 是DV10发酵黄精酒的关键香气组分, 赋予了DV10发酵黄精酒花香、果香和奶油香甜的香气。BRG发酵黄精酒挥发性物质中有硫化氢(H2S), D254发酵黄精酒关键香气组分较少。感官评价结果显示BRG发酵黄精酒存在臭鸡蛋气味, 与HS-SPME-GC-MS分析结果一致, 对酒体感官造成了负面影响。DV10发酵黄精酒综合感官评价结果最优。结论 通过3种酵母发酵均可提高黄精浸提液的皂苷、总酚和总黄酮含量及抗氧化活性, DV10酵母发酵的黄精酒酒精度高, 滋味和香气协调, 酯类物质含量较高, 以黄精香和花果香为主, 品质较优, 可作为酿制黄精酒的参考商业菌株。     

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。     

Bacteriological properties and health-related biochemical components of fermented fish sauce: An overview

Fish sauce is an amber-colored salty liquid in Southeast Asian cuisine used as an important condiment for improving the taste of foods. It is produced by fermenting the fish with salt in the ratios of 1:1 or 3:1 (fish:salt, wet wt) in underground concrete tanks or earthenware for 6–12 months at ambient conditions. Proteins of the raw materials are hydrolyzed into peptides and amino acids by microbial proteolytic enzymes during fermentation. This paper reviews fish sauce diversity and its bacteriological, biochemical, and biofunctional properties. Additionally, efforts to accelerate fish sauce production by employing halotolerant bacterial cultures and proteinases to reduce the fermentation period and also to improve the acceptability of the product are also reviewed. Further, the review provides an overview of bacterial proteinases that have been employed to enhance the sensory and microbiological quality of fish sauce. The review also outlines the effect of fermented fish sauces on health, especially in reference to several bioactive peptides and bacterial metabolites apart from discussing desalination technique to recover the metabolites from fish sauce.     

嗜盐四联球菌SNTH-1产多肽发酵条件优化及其呈味、抗氧化特性

该研究以产多肽能力较强的嗜盐四联球菌（Tetragenococcus halophilus）SNTH-1为试验菌株,大豆蛋白为发酵基质,通过单因素试验、Plackett-Burman试验、最陡爬坡试验及Box-Behnken响应面试验对其产多肽培养条件进行优化,并对其呈味及抗氧化特性进行研究。结果表明,嗜盐四联球菌SNTH-1产多肽的最优培养条件为：发酵时间40 h、盐度5.2%、发酵温度37 ℃、接种量3%、初始pH值8.1,在此优化条件下,多肽含量为（32.96±0.02）mg/mL。菌株SNTH-1所产多肽的鲜味、厚味、甜味、咸味、苦味的风味强度较优化前有所提高,清除1,1-二苯基-2-三硝基苯肼（DPPH）自由基的半抑制浓度（IC50）值为0.22 mg/mL。     

西兰花乳清发酵饮料工艺优化及其抗氧化活性研究

目的: 为改善乳清资源的浪费现象,开发功能性复合乳清产品。方法：以乳清、西兰花为原料,采用益生菌菌蔬酵素浸泡发酵,通过单因素和正交试验筛选最优工艺,进一步添加品质改良剂调配,制备西兰花乳清发酵饮料,并对产品的感官、理化、微生物以及抗氧化活性进行研究。结果：筛选的最佳工艺为：乳清添加量64.685%,切块西兰花添加量20%,白砂糖15%,发酵剂0.050%,35 ℃发酵6 d;滤出西兰花,向滤液中添加0.265%品质改良剂（最佳调配工艺为：海藻酸钠0.150%,β-环糊精0.100%,柠檬酸钠0.015%）,混匀,均质。产品pH 3.84±0.07,糖度8 OBx,粗蛋白(1.8±0.04) g/100 g,乳酸菌含量1.4×106 CFU/mL,DPPH自由基清除率94.67%±2.73%,ABTS+自由基清除率96.33%±1.01%,还原能力87.23±2.44 A700 nm,SOD酶活(713.08±17.52) U/mL。讨论：西兰花乳清发酵饮料色香味俱佳、口感浓郁顺滑、营养丰富,有较高的抗氧化活性,具有较好的开发前景。     

Isoflavone profiles,phenol content,and antioxidant activity of soybean seeds as influenced by cultivar and growing location in Ohio

Isoflavone levels and isoflavone chemical composition in soybeans vary between planting locations although the exact factors which control isoflavone biosynthesis are unclear. We compared levels of 12 isoflavones in soybean seeds of six cultivars grown in four different locations in Ohio in 2002 as determined by high‐performance liquid chromatography. Antioxidant activity contained in plant‐based foods can improve food oxidative stability and phenolics and isoflavones have proven active in food systems. Radical scavenging activity was assessed using the 2,2‐diphenyl‐1‐picrylhydrazyl (DPPH) radical. Total phenolics (TPCs) were determined by using Folin–Ciocalteu reagent. Total isoflavones (TIs) varied five‐fold (1573–7710 nmol g^?1) between seeds from the various location–cultivar combinations. One location (Wooster, Ohio) produced seeds containing half the isoflavones as the other locations tested apparently due to poor growing conditions. The cultivars could be divided into two groups based on TI, one having approximately 50% more isoflavones. Surprisingly, across the entire data set, with increasing TI, the proportion of isoflavones accounted for by the daidzein family increased due primarily to malonyl daidzin. DPPH scavenging did not differ significantly by location or cultivar (P > 0.05) and did not correlate with TPC or TI. Profiling soybean isoflavones could help elucidate how isoflavone biosynthesis is regulated and lead to better disease resistance of soybean crops and soy foods with greater health benefits. Copyright © 2007 Society of Chemical Industry     

抹茶茶汤感官理化特性、多酚组成及抗氧化活性研究

研究了两种市售抹茶茶汤理化指标、多酚化学组成及抗氧化活性,并进行感官审评。结果表明:随着冲泡次数的增加,抹茶汤的pH值增加,可滴定酸含量降低,色泽明亮度增加但黄蓝度降低。同时,一泡茶汤较二泡、三泡茶汤具有最优的色香味感官品质。此外,两种抹茶茶汤的总多酚含量、多酚组成及体外抗氧化活性无显著差异,但均随冲泡次数递减;UPLC所分析茶汤中的9种化学物质中含量相对较高的成分依次为表没食子儿茶素没食子酸酯、咖啡因和表没食子儿茶素。     

红衣组分对花生分离蛋白及其酶解产物理化和抗氧化性质的影响

以花生为原料,研究了花生红衣组分对花生分离蛋白及其酶解产物理化和抗氧化性质的影响。研究结果表明:含红衣的分离蛋白酶解速度低于不含红衣的;相同水解度条件下,含红衣的表面疏水性小于脱红衣的;GPC分布中,含红衣的峰值大于脱红衣的;红衣组分能够提高花生分离蛋白及其酶解产物的溶解性、乳化稳定性、乳化活性;在相同水解度条件下,含红衣的水解产物多酚含量显著高于脱红衣的,多酚含量的差异与花生分离蛋白及其水解产物的抗氧化性具有正相关性。