焙烤工艺对鹰嘴豆营养品质及风味的影响

以鹰嘴豆为原料,研究150 ℃和200 ℃焙烤工艺对鹰嘴豆营养品质及风味的影响。结果表明,150 ℃焙烤不同时间对蛋白质、总多酚含量影响不大,而淀粉、总黄酮含量随焙烤时间变化而波动,其中总黄酮含量在150 ℃焙烤10 min 时达到最高值2.29 mg/g;200 ℃焙烤不同时间对淀粉、蛋白质含量影响不大,而200 ℃焙烤60 min 时总多酚含量明显增加至3.92 mg/g,总黄酮含量随焙烤时间延长整体呈现增加趋势;150 ℃和200 ℃焙烤30 min 以后,粗脂肪及油酸（C18∶1）、亚油酸（C18∶2）等不饱和脂肪酸含量随焙烤时间延长呈明显降低趋势,而棕榈酸（C16∶0）、硬脂酸（C18∶0）等饱和脂肪酸的含量呈明显升高趋势。通过全二维气相色谱-飞行时间质谱分析,共鉴定出222 种挥发性成分,不同焙烤条件会明显改变鹰嘴豆挥发性成分组成和含量,增加挥发性成分种类,其中,吡嗪类是鹰嘴豆中种类丰富、含量高的挥发性成分,其总体表现为150 ℃焙烤30 min 或200 ℃焙烤10 min 内呈现降低趋势,随后随着焙烤时间延长呈升高趋势。结果表明,不同焙烤工艺对鹰嘴豆营养品质及风味影响较大,低温短时间焙烤可以提升鹰嘴豆营养品质和风味。     

焙烤对核桃仁风味及其油脂氧化的影响

焙烤可以有效增加坚果的风味,但由于坚果中含有的大量不饱和脂肪酸极易受热氧化,因此要严格控制焙烤工艺.以带囊衣核桃仁作为研究材料,对不同温度和时间下焙烤的核桃仁进行了风味评定和油脂过氧化值的测定,得到125℃,4 h是油脂氧化程度最小而风味最佳的焙烤条件.     

美拉德反应对焙烤花生特征风味形成的影响

通过模拟焙烤花生过程中的美拉德反应,制备焙烤花生风味物质。并利用GC-MS对反应产物中的挥发性成分进行鉴定,并与烤花生和花生香精的挥发性成分进行比较。同时还研究了温度、时间、底物浓度、水分含量对美拉德反应中2,5-二甲基吡嗪产量的影响。实验结果表明反应产物具有浓郁的焙烤花生香味,在反应产物的20种挥发性成分中,有11种与烤花生相同,12种与花生香精相同。     

油菜籽微波过程对油中焙烤风味形成的影响

微波预处理油菜籽能使菜籽油形成浓郁的焙烤风味。利用顶空固相微萃取-气质联用技术结合香气稀释因子分析对微波压榨菜籽油中具有焙烤风味的关键成分进行鉴定,同时考察油菜籽微波过程中游离糖、游离氨基酸、体系温度和油菜籽水分的变化。结果表明:微波压榨菜籽油中共鉴定出13种具有焙烤风味的挥发性成分,包括9种吡嗪类物质,以及醇类、醛类、呋喃和噻唑类物质各1种,其中FD因子大于等于32的包括2,5-二甲基吡嗪、2,6-二甲基吡嗪、5-甲基呋喃醛、2-乙基-6-甲基吡嗪、2-乙基-5-甲基吡嗪和3-乙基-2,5-二甲基吡嗪,这6种物质对菜籽油中焙烤风味的贡献最大;油菜籽微波0～8 min过程中,除蔗糖外,其他游离糖(果糖、葡萄糖)和游离氨基酸呈现逐渐降低的趋势,根据含量变化及相关性分析,初步推测参与菜籽油焙烤风味形成的可能前体物质是葡萄糖、果糖、天门冬氨酸、亮氨酸和赖氨酸。     

焙烤对甜荞关键组分及风味物质的影响研究进展

甜荞是一种高营养价值的功能性杂粮,焙烤是改善甜荞粉风味的一种工艺,其对甜荞的淀粉、蛋白、抗氧化物活性物质及风味物质有显著影响。其中,经过焙烤后的甜荞粉,淀粉糊化程度增加,糊化温度升高,结晶程度降低,淀粉颗粒结构被破坏;蛋白质性质发生变化,氨基酸含量增加;抗氧化活性物质含量随焙烤程度呈先增加后降低的趋势。此外,焙烤使甜荞粉风味丰富,增加了吡嗪类物质,使甜荞粉的风味中添加坚果味以及焦香味,甜荞粉的风味得到改善。本文首先从甜荞的焙烤工艺入手,重点回顾了焙烤过程对甜荞籽粒及甜荞粉的关键组分及风味物质的影响,并对影响甜荞焙烤品质的关键因素进行了分析,最后,对焙烤甜荞的应用前景进行了展望。     

焙烤糯米粉的关键风味物质分析

焙烤糯米粉是通过烤箱高温焙烤改善糯米粉风味性质的改性产品。以感官评定、气相色谱-质谱联用(GC-MS)和气相色谱-嗅觉测定法(GC-O)为表征手段,对糯米粉焙烤后的关键风味物质进行分析。结果表明,焙烤后的米粉整体风味品质显著提高,共检测出风味物质103种,相比较于焙烤前增加了33种,总质量浓度从7. 49 mg/L增加至94. 12 mg/L。种类和浓度增加较明显的为醛类、酮类和杂环化合物。其中关键的风味物质共10种,包括己醛、辛醛、壬醛、癸醛、反-2-癸烯醛、2,4-癸二烯醛、2-戊基呋喃、1-辛烯-3-醇、丁酸丁酯、2-叔丁基-3,4,5,6-四氢吡啶,这些关键风味物质可能产生于高温下的美拉德反应。综上,经过焙烤,米粉被赋予了更为浓郁的风味。     

卵磷脂对面包焙烤品质的影响

研究选用卵磷脂作面团乳化剂 ,使油脂乳化分散 ,以改善面筋的网络结构 ,影响面包的体积 ,从而改善面包的纹理结构。通过对实验结果的评判 ,来判断它们对面包焙烤性质的影响 ,确定它在面包制作过程中的添加量 ,对卵磷脂加入所产生的其它问题也进行了分析讨论。     

黑豆不同发芽期多酚、黄酮及抗氧化活性分析

为增加黑豆利用价值、拓宽黑豆资源利用渠道,选取黑豆为原料水培发芽,测定黑豆不同发芽期多酚、黄酮、花青素含量和对DPPH·、ABTS⁺·和·OH的清除能力,并分析活性物质与抗氧化性之间的相关性。结果表明:黑豆不同发芽期多酚、黄酮含量呈不断上升趋势,发芽至84 h,多酚含量达到最大值,为8.3 mg/g;发芽至96 h,黄酮含量最高,为8.5 mg/g,相对于萌芽初期,多酚及黄酮含量增加显著(P<0.05),而花青素含量不断下降。黑豆发芽84 h时对DPPH·清除率最大,为57.18%,在96 h对ABTS⁺·清除率最大,为54.78%,在72 h时对·OH清除率最大,为26.13%。相关性分析表明,黑豆发芽过程中多酚、黄酮含量与其对DPPH·、ABTS⁺·和·OH清除能力均呈一定正相关(P<0.05)。试验为水培黑豆芽苗菜的选育提供技术支撑,为黑豆芽苗菜功能性产品的开发及综合利用提供理论依据。     

三叶木通不同部位多酚、黄酮含量及抗氧化活性比较

分别用超声波法和回流提取法对三叶木通不同部位进行提取,测定不同处理条件下不同部位的多酚和黄酮含量及抗氧化能力。结果表明,超声波提取法优于回流提取法,不同部位中以藤茎超声波提取物多酚、黄酮含量最高和抗氧化能力最强,其多酚含量(TPC)、黄酮含量(TFC)、DPPH自由基清除能力(DPPH)、ABTS自由基清除能力(ABTS)、铁还原抗氧化能力(FRAP)值分别为(63.033±0.482)mg/g,(26.395±0.731)mg/g,(380.860±5.462)μmol Trolox/g,(337.181±1.586)μmol Trolox/g,(387.406±1.773)μmol Trolox/g。两种方法测得的多酚和黄酮含量及抗氧化活性均呈现以下趋势:藤茎叶片果皮种子果肉。Spearman相关性研究表明,多酚、黄酮含量与抗氧化活性呈强相关。研究结果为三叶木通的深加工利用提供了理论依据。     

红松壳多酚、黄酮和多糖含量及抗氧化活性相关性的研究

为了探究红松壳中主要活性成分的含量及其与抗氧化活性之间的相关性,试验以伊春红松壳为原料,使用不同浓度乙醇溶剂提取红松壳多酚、黄酮和多糖并分析其含量,采用SPSS软件分析松壳中活性物质与抗氧化活性之间的相关性。试验结果表明,当乙醇的浓度为40%时,红松壳多酚、黄酮和多糖得率均最高,分别为4.05 mg/g、1.7 mg/g和7.05 mg/g。抗氧化活性试验表明,红松壳多酚抗氧化活性显著高于黄酮和多糖,与Vc抗氧化活性相当。其中松壳多酚对DPPH·的IC50(半数清除率浓度)值是0.20±0.05μg/m L,对·OH的IC50值是13.04±0.04μg/m L,对总还原力的IC50值是40.15±0.06μg/m L。相关性分析结果也表明松壳多酚与抗氧化活性相关性最高,其中松壳多酚与DPPH·相关性是0.908,与·OH相关性是0.989,与总还原力相关性是0.989(p0.01),可以看出松壳多酚是主要的抗氧化成分。本实验研究的结果为伊春红松壳副产物的综合利用以及开发天然抗氧化剂提供了科学依据。     

Improved Fermentation of Cocoa Beans with Enhanced Aroma Profiles

The cocoa (Theobroma cacao) fermentation was carried out using starter consortia of Saccharomyces cerevisiae, Lactobacillus plantarum, and Acetobacter aceti with 10% inoculum. The fermented beans were soaked with sterile water (1:3 wt/v) for the duration of 1, 3, and 5 h. The treated beans were dried to the moisture content of 7 ± 1%. The samples were then roasted, ground and subjected to steam distillation. The volatiles were extracted and identified using GC-MS. The samples soaked for 1 h scored 100% cut score along with 0.85% fermentation index. The volatile and non-volatiles were associated with beans treated in water after fermentation. Volatile compounds were classified as esters, alcohols, acids, aldehydes, ketones, pyrazines, hydroperoxides, and hydrocarbons. Most of the oxygenated aliphatic compounds and aromatics were potentially derived via an acetic acid and shikimic acid pathways, respectively. Untreated cocoa beans contained 12 sesquiterpene hydrocarbons potentially derived through the mevalonic acid pathway and contributed to harsh notes. Also, these metabolites were completely absent in the treated samples indicating depletion while soaking. Thus, the treated samples (1 h) had enhanced quality with high flavor notes with 8.5 rating on sensory evaluation. Thus, these soaking treatments with fermentation lead to improvement of flavor profiles which confers improved cocoa quality.     

Effect of Different Mixing Intervals on the Fermentation of Cocoa Beans

Four mixing intervals (6, 12, 18 and 24 h) were compared with special reference to three selected cacao varieties from two locations of Sri Lanka. Cocoa beans were fermented for 6 days by using the ‘sweat box’ fermentation method. Irrespective of location and variety, product prepared by using all mixing intervals were significantly different with variations in temperature as well as degree of fermentation. Frequent mixing (at 6 and 12 h) produced a higher number of well-fermented beans than other treatments. When practical aspects of fermentation in both small and large scale contexts are considered, mixing at 12 h intervals for 6 days can be recommended as the most suitable treatment for three varieties tested from two locations. © 1997 SCI.     

Sequencing and Identification of Different Salmonella Species in Cocoa Beans Treated with Gamma Irradiation

Gamma irradiation is an effective way to eliminate the bacterial load in cocoa beans. During harvesting these are exposed to various factors of contamination. The aim of this study was to analyze the effect of gamma irradiation on the presence of Salmonella spp considered a microbiological risk in chocolate. Cocoa samples (n = 31) were treated with three doses of gamma irradiation (2, 3 and 5 kGy) besides a control sample without irradiation. The PCR method revealed 22 bacteria (n = 124) with Salm3-Salm4 amplified. The DNA sequencing method confirmed the presence of two isolates who belong to Salmonella spp. and 20 belonging to Klebsiella sp and Enterobacter sp. These results were retrieved from the control samples and irradiation 2kGy, while radiation 3 to 5 kGy no growth of microorganisms.     

15种黄酮类化合物对烤鸡胸肉中杂环胺含量的影响

为研究15 种黄酮类化合物对烤鸡胸肉中5 种杂环胺含量的影响,将烤鸡胸肉经NaOH提取、乙酸乙酯萃取,通过Oasis MCX固相萃取小柱净化后,采用超高效液相色谱-串联质谱法对杂环胺含量进行分析,并采用主成分分析法研究黄酮类化合物对烤鸡胸肉中杂环胺形成影响的差异性。结果表明,15 种黄酮类化合物中染料木素、表没食子儿茶素没食子酸酯（epigallocatechin gallate,EGCG）和木犀草素对烤鸡胸肉中1-甲基-9H-吡啶并[3,4-b]吲哚和9H-吡啶并[3,4-b]吲哚抑制作用较好,抑制率达20%以上;EGCG、柚皮素、木犀草素和染料木素对2-氨基-1-甲基-6-苯基-咪唑并[4,5-b]吡啶抑制作用较好,抑制率达45%以上;染料木素、柚皮素和木犀草素对2-氨基-3,8-二甲基咪唑并[4,5-f]喹喔啉和2-氨基-3,4,8-三甲基-3H-咪唑并[4,5-f]喹喔啉抑制作用较好,抑制率达45%以上。主成分分析结果显示,EGCG、木犀草素和染料木素聚为一类,且对5 种杂环胺均有较强的抑制作用。通过化学结构推测得出,黄酮母核中A环同时存在5-羟基和7-羟基,B环的4’-羟基对黄酮类化合物有效抑制烤鸡胸肉中杂环胺的形成具有重要作用,而C环中3-羟基的存在会降低其对杂环胺形成的抑制作用。综上,黄酮类化合物对杂环胺的形成具有影响,EGCG、木犀草素和染料木素的抑制作用最强,可为高温肉制品安全加工提供理论参考。     

Food Evolution: The Impact of Society and Science on the Fermentation of Cocoa Beans

Cocoa is part of the cultural heritage in many areas of South and Central America and has played an important role in the history of human culture there. The modern methods of cocoa bean production for the purpose of the manufacture of modern chocolate are tied to the origin and development of cocoa bean fermentation and processing methods and the science of microbiology. To date, however, there has not been a study that discusses the impacts of both science and culture on the evolution of cocoa beans and cocoa bean processing. This work provides both a detailed overview of the evolution and historical development of cocoa, from its earliest forms to modern chocolate manufacturing, an in‐depth discussion of the biochemistry of cocoa bean fermentation, as well as a compilation of primary research studies with details on fermentation methods, the scientific bases of interactions in microbial fermentations, and methods for their investigation, as well as metabolites that are produced. As a result, we present here the major microorganisms among all the ones that have been identified in previous studies. This database will aid researchers seeking standardized inoculants to drive cocoa bean fermentation, as well as serve as a guide for inventorying and assessing other food evolution–related studies regarding traditional and artisanal‐based food systems.     

十种蜂花粉醇提物中总多酚和总黄酮含量测定

为测定蜂花粉的功能性成分,用不同浓度乙醇对蒲公英、野菊花、桃花、山楂、野藿香、黄玫瑰、野玫瑰、黄柏、山花、五味子十种蜂花粉进行提取。结果表明:桃花花粉多酚提取适宜用水或低醇,野藿香花粉水提多酚提取量高于醇提物,山楂花粉和山花花粉适宜用70%乙醇提取多酚,其余六种蜂花粉选用70%～80%乙醇提取多酚效果比较好;山花花粉适宜用无水乙醇提取黄酮,野菊花花粉适宜用70%乙醇提取黄酮,其余八种蜂花粉选用80%乙醇提取黄酮效果较好。黄玫瑰花粉的总多酚和总黄酮含量均为最高,野藿香花粉中总多酚和总黄酮含量都最低。     

Roasting Effects on Dietary Fiber Composition of Cocoa Beans

The effect of roasting on dietary fiber fractions of cocoa beans was determined by gravimetric and fractionation procedures after enzymatic treatment. Roasting had no notable effect on total dietary fiber content (TDF). Components of insoluble dietary fiber (IDF) became redistributed after roasting. One of the largest changes was a sharp increase of Klason lignin. The noted decrease in sugar content without a change in IDF suggested that neutral sugars and uronic acids may be involved in Maillard polymer formation. Soluble dietary fiber (SDF) did not show large variations. Undigestible protein in IDF increased after roasting.     

5种豆类中总多酚、总黄酮含量及抗氧化活性比较研究

以黑豆、绿豆、红小豆、大豆和豇豆5种豆类为研究对象,测定其乙醇提取物总多酚和总黄酮含量,并通过4个指标比较其体外抗氧化活性。结果表明,5种不同豆类中总多酚和总黄酮含量分别在2.05 mg/g^6.33 mg/g和1.50 mg/g^4.09 mg/g的范围内,其中黑豆的总多酚和总黄酮含量都最高,分别为6.33 mg/g和4.09 mg/g;5种豆类对DPPH自由基、羟基自由基、超氧阴离子自由基的清除能力都比较高,黑豆的清除力最强,其对3种自由基的清除能力分别为80.92%、77.42%和81.62%;相关性分析表明5种豆类的总多酚含量和总黄酮含量之间呈极显著正相关(P<0.01),这两种活性成分含量和DPPH自由基、羟基自由基、超氧阴离子自由基清除能力之间都呈正相关,其中总黄酮含量和超氧阴离子自由基清除能力之间呈显著正相关(P<0.05)。     

六种蜂花粉多酚和黄酮类物质含量测定及抗氧化性的研究

对六种不同蜂花粉中多酚及黄酮类物质进行定量,并且进行了醇提物抗氧化性的初步探讨。结果表明,这六种蜂花粉均有比较强的DPPH·自由基清除能力以及还原能力,是一种优良的天然抗氧化剂。     

赤霞珠葡萄梗黄酮、原花青素和多酚的提取工艺优化

研究赤霞珠葡萄梗中黄酮、原花青素和多酚的提取工艺。以葡萄梗中黄酮、原花青素和多酚含量的综合评分为评价指标,采用正交设计优化赤霞珠葡萄梗黄酮、原花青素和多酚超声辅助双水相提取的条件。结果表明:超声辅助双水相提取的最优工艺条件为:料液比为1:40(g/mL)、超声时间为50 min、乙醇质量分数为24%、硫酸铵质量分数为20%。在此提取条件下,放大8倍赤霞珠葡萄梗中黄酮、多酚和原花青素的含量分别为72.85、122.21、87.67 mg/g,相对标准偏差在3%以内,说明该工艺具有可行性。