贵州辣椒的降氟技术研究

为降低贵州辣椒中的氟化物含量,采取不同的干制方法和浸泡、蒸煮、清洗等加工处理,对贵州辣椒中的氟含量进行控制。结果表明,通过采用清洗、浸泡处理,以及提高浸泡温度或进行蒸煮处理,均可明显降低由于煤烟所导致的氟化物含量。工艺为:采用常温浸泡30 min、或高温蒸煮10 min后清洗2次,即可获得降低贵州辣椒中氟含量的较好效果。     

不同产地薏米的营养品质比较

选取贵州兴仁、福建浦城、云南师宗、老挝万象4个产地的薏米,对其基本营养组成、矿物元素、维生素、总多糖、总多酚、总黄酮含量进行测定。此外,分析比较不同产地薏米蒸煮后的吸水率、膨胀率、硬度和弹性,并对蒸煮后的薏米进行感官评价。结果表明,贵州兴仁薏米的蛋白质含量较高;云南师宗和老挝万象薏米油酸含量要显著高于其它产地薏米（p＜0.05）;云南师宗和老挝万象薏米维生素E的含量明显优于其它产地的薏米（p＜0.05）;贵州兴仁薏米总多糖含量显著高于其它产地薏米（p＜0.05）。蒸煮后薏米的吸水率和膨胀率排序为：云南师宗薏米＞福建浦城薏米＞贵州兴仁薏米＞老挝万象薏米;蒸煮后云南师宗和老挝万象薏米较硬,弹性较大;贵州兴仁薏米蒸煮后的感官评分要明显优于其它3个产地薏米。     

醋酸浸泡蒸煮联合处理对干制罗非鱼骨质量的影响

本文研究了在醋酸浸泡蒸煮联合处理(0.15MPa,120℃,5～120min,醋酸浓度0～12%)对干制后罗非鱼骨质量的影响。结果表明:延长热处理时间和增大醋酸浸泡浓度均可使干制后的鱼骨相对硬度及其羟脯氨酸含量降低,并使灰分含量相应增加;钙磷比经蒸煮处理后显著变小;醋酸浸泡蒸煮联合处理比单纯的蒸煮处理对鱼骨有更高的软化效率。对于不同醋酸浸泡热处理的干制鱼骨,其羟脯氨酸含量和相对硬度的对数成极显著的线性关系(P0.01),这表明醋酸浸泡蒸煮联合处理可能主要是通过减少鱼骨中的胶原蛋白来实现其对鱼骨的软化作用的。     

蒸煮工艺参数对绿豆糊化特性的影响

浸泡和蒸煮是豆类食品加工的必须程序,直接影响产品的品质。通过对不同浸泡时间下绿豆胀豆率以及不同蒸煮时间对绿豆硬度和糊化特性的影响研究,确定了绿豆的最佳泡豆温度为35℃、时间为5h、最佳蒸煮时间为15min;并建立了绿豆硬度和糊化度、糊化度与RVA糊化特性各特征值之间的线性回归方程,证明糊化度和硬度、糊化度和RVA特征值之间存在极显著的线性关系。     

浸泡、蒸煮工艺对大豆品质特性的研究

对大豆浸泡、蒸煮等预处理工艺条件进行了研究.结果表明,浸泡工艺最佳条件:在25℃下,豆水按照比例1:3,浸泡时间为12 h,大豆的完全吸水率可达到2.1.使用物性仪分别测定了不同蒸煮温度和时间下大豆的硬度、弹性、咀嚼性,发现其中硬度、弹性、咀嚼性随温度的升高而逐渐下降,而脆性变化无明显规律.大豆的前处理最佳工艺条件:蒸煮温度为112℃,豆水为1:1.2,蒸煮时间为25min.     

浸泡时间对薏米蒸煮过程中水分分布的影响

为研究浸泡对薏米在蒸煮过程的影响,将薏米浸泡不同时间(0、30、60、90、120、150 min),采用低场核磁共振技术(LF-NMR)研究薏米在蒸煮过程中水分的分布状态和流动性变化,并研究不同浸泡时间对薏米蒸煮过程中吸水率、膨胀率、质构的影响。结果表明:随着蒸煮时间和浸泡时间增加,薏米的吸水率和膨胀率增大,硬度降低;薏米在蒸煮过程中的弹性呈下降趋势,浸泡增大了薏米在蒸煮过程中的弹性,浸泡后的薏米在蒸煮过程中的弹性无显著差异;浸泡缩短薏米蒸煮时间,蒸煮过程中易流动水转变为不易流动水,且随着浸泡时间的增加,易流动水转变为不易流动水的速度先增大后下降。主成分分析结果表明主成分1(吸水率、膨胀率、T_(21b)、T_(22)、M_(22)、M_(21b)、硬度、弹性)、主成分2(T_(21a)、T_(21b)、T_(22)、M_(21a)、M_(21b))和主成分3(T_(21a)、M_(21a)、M_(21b))前三个主成分可以解释变异方差的88. 87%,并且浸泡薏米与未浸泡薏米在样品评分图上显著分开。     

几种糙米性质研究及隆粳软1号糙米蒸煮条件优化

对几种糙米的成分、断面结构以及RVA特征谱进行研究,同时优化了新型米种隆粳软1号的蒸煮条件,为更好地探究新型米种的性质及其应用前景提供了研究思路和理论基础。本研究采用RVA-Super4快速粘度分析仪进行糙米粉糊化特性的快速测定,并测定了不同米种水分、总淀粉、蛋白质、脂肪、直链淀粉、总膳食纤维以及灰分的含量。通过单因素实验确定浸泡温度、浸泡时间、蒸煮加水量对隆粳软1号糙米蒸煮品质的影响,并结合响应面分析法得到隆粳软1号糙米最佳蒸煮工艺条件为:浸泡时间40 min,浸泡温度38 ℃,蒸煮加水量为1:1.8,此条件下隆粳软1号糙米蒸煮食味品质较好,硬度与黏度比值为32.98±0.21,为解决新型米饭蒸煮问题提供了参考。     

超声辅助鸡爪胶原蛋白肽处理对鸡胸肉贮藏品质的影响

探究4 ℃（冷鲜）与－18 ℃（冷冻）条件下超声辅助鸡爪胶原蛋白肽处理对鸡胸肉贮藏品质的影响。设置未处理、去离子水浸泡、超声辅助去离子水浸泡、鸡爪胶原蛋白肽溶液浸泡、超声辅助鸡爪胶原蛋白肽溶液浸泡5 个处理组,研究4、－18 ℃贮藏期间鸡胸肉的品质变化,包括滴水损失率、蒸煮损失率、水分分布、质构指标和组织结构变化。结果表明：随着贮藏时间的延长,2 个贮藏温度下的鸡胸肉水分构成均发生大幅改变,4 ℃组的不易流动水向自由水大量转化,导致滴水损失率和蒸煮损失率变化的上升速率更快,－18 ℃组的水分迁移程度较小;4 ℃组鸡胸肉的保水性较差;超声处理组的质构参数得到显著改善（硬度降低、弹性增加）,且对鸡胸肉色泽无显著影响。超声辅助鸡爪胶原蛋白肽处理能显著提高鸡胸肉贮藏期内的品质。     

鲜湿方便米饭制备工艺

以市场上常见的大米为原料制作鲜湿方便米饭,研究了浸泡时间、浸泡温度、蒸煮温度、蒸煮时间、蒸煮压力对鲜湿方便米饭食味品质的影响,以及不同添加量的低聚果糖对鲜湿方便米饭质构、感官评分的影响以及不同储存时间下不同添加量的低聚果糖对米饭硬度、粘性、感官评分和回生焓的影响。试验结果表明,鲜湿方便米饭的最适浸泡温度为45 ℃,浸泡时间为60 min;蒸煮工艺蒸煮压力为0.25 Mpa、蒸煮时间30 min、蒸煮米水比1∶0.9;在鲜湿方便米饭中添加1.5%低聚果糖时,有明显抗老化效果,鲜湿方便米饭的感官评分最高。     

微波蒸煮对米粉品质的影响

考察不同微波功率对浸泡与未浸泡两种预处理米粉品质的影响,通过失重率、碘蓝值、酶解力、质构特性的检测,优化微波蒸煮条件,为微波即食米粉的开发提供理论依据。实验结果表明浸泡过程对米粉的蒸煮品质影响较小;米粉的失重率、硬度和粘结性随着微波功率的提高而增加,回弹性和酶解力受微波功率影响较小;600W微波功率蒸煮的米粉碘蓝值最高。     

陈窖豆豉粑传统工艺剖析及优势菌群鉴定

工艺独特的贵州黔西、大方两地陈窖豆豉粑微生物区系分离鉴定结果表明,黔西陈窖豆豉粑以泛酸芽胞杆菌(B.pantothenticus)、蜂房芽胞杆菌(B.alvei)、坚强芽胞杆菌(B.firmus)等芽胞杆菌为优势菌群,为细菌发酵型产品,而大方陈窖豆豉粑则是爪哇毛霉(M.javanicusWehmer)、鲁氏毛霉(M.rouxians(Calmette)Wehmer)、总状毛霉(M.racemosusFres.)、坚强芽胞杆菌、革兰氏阳性无芽胞杆菌等霉菌和细菌共存发酵的复合发酵型产品,同时两地产品的后期陈窖阶段,均有球菌(Stophylococcus或Pediococcus)和酵母菌(HansenulaanomalaH.etp.sydowvar.amomala)富集,可能对产品的风味和营养起着一定作用。     

FORMATION OF TASTE AND ODOR COMPOUNDS DURING PREPARATION OF DOUCHIBA, A CHINESE TRADITIONAL SOY-FERMENTED APPETIZER

Douchiba (DCB), a Chinese traditional soy‐fermented appetizer, is abundantly produced and widely consumed in Guizhou province of southwest China. In this study, an analysis of free amino acid (FAA) profiles, low‐molecular weight peptide fractions (LMWPFs), hydrophobic bitter peptide fractions (HBPFs) and volatile compounds was conducted to understand the changes in taste and odor compounds of DCB during five consecutive manufacturing stages: steamed soybean (SS), 5‐day incubated Koji (Koji), 6‐month fermented Douchi, semifinished Douchiba (sm‐DCB) and 6‐month ripened finished Douchiba (DCB). The total free amino acids (TFAAs) increased significantly from SS to DCB by about 11 times and amounted to 20.1% of the crude protein. Arg, Glu, Phe, Leu and Lys were the most abundant FAA at the end of ripening, and were 64.6% of TFAA. The most abundant taste active FAA classes were the bitter FAA, representing eight‐ and threefold increases over sweet and MSG‐like FAA, respectively. The final values of all bitter and monosodium glutamate‐like (MSG‐like) FAA at DCB stage were significantly higher than their respective thresholds. The ratio of oligopeptides (500～1000 Da) accounted for 13.8 and 2.5% of LMWPF and HBPF, respectively. However, the taste of DCB was predominated by saltiness, followed by moderate “umami” taste and slight bitterness, likely as a result of the balance and interaction among different taste components. A total of 122 volatile compounds were identified, including alcohols, acids, esters, aldehydes, ketones, phenols, sulfur‐containing compounds, heterocyclic compounds, alkines, benzenes and spice aromatics. The subtle aroma of the finished DCB seemed to depend not only on particular key compounds but also on a “critical balance” or a “weighted concentration ratio” of 60 compounds. These volatile compounds, mainly derived from lipid oxidation, amino acid degradation, carbohydrate fermentation, Maillard reaction and Strecker degradation during the microbial metabolism, enzymatic catalysis and spontaneous reactions.     

陈窖豆豉粑类黑精提取及骨架肽段氨基酸组成分析

发酵期18个月的陈窖豆豉粑,其类黑精含量按Hashiba方法以干基计为4.76%。采用优化的常温分离提取工艺获得的类黑精组分经氨基酸分析表明,陈窖豆豉粑类黑精骨架由肽段构成,并且肽段中最具类黑精形成活性的氨基酸残基主要是天冬氨酸(Asp)、谷氨酸(Glu)、精氨酸(Arg)、赖氨酸(Lys)和脯氨酸(Pro)。     

传统陈窖豆豉粑和霉菌型豆豉挥发性风味化合物研究

采用顶空固相微萃取（HS—SPME）和气质联用（GC—MS）方法，共鉴定出贵州传统陈窖豆豉粑和霉菌型豆豉四个样品中的挥发性化合物102种，其中DCB-1、DCB-2、DCB-3和LGM-DC分别为65、48、50和47种，这些化合物包括醇（16）、酸（13）、酯（18）、醛（5）、酮（11）、酚（2）、吡嗪（11）、呋喃（9）、吡喃酮（2）、含硫化合物（4）、酰胺类化合物（9）以及其它化合物（2）等12类。已报道的对大豆发酵调味品风味贡献较大的41种化合物至少在三个样品中同时检出。就Maillard反应特征产物之一的吡嗪类化合物而占，其含量仅次于酸，可能对产品主体风味的形成起着重要作用。     

熟豆豆浆馒头与传统小麦粉馒头的感官品质及营养成分对比

本文以大豆、小麦富强粉为主要原料制成熟豆豆浆馒头,与传统加工工艺制成标准粉馒头和富强粉馒头进行感官评价和营养成分对比.结果表明:在感官品质的对比中,三种馒头感官品质的总得分和气味方面的得分为熟豆豆浆馒头＞富强粉馒头＞标准粉馒头,在粘牙方面的得分为熟豆豆浆馒头大于标准粉馒头和富强粉馒头,在色泽方面的得分为熟豆豆浆馒头和富...     

核磁共振技术研究馒头水分的迁移变化

利用NMR(nuclear magnetic resonance)技术和质构分析法(texture profile analysis)从分子水平上探讨水分在馒头储藏过程中的迁移情况。通过对馒头的硬度和NMR 参数之间进行相关分析,发现它们之间具有显著相关性(p<0.01)。实验结果表明：储藏期间馒头的硬度指标与其水分存在状态的变化密切相关,水分迁移运动是导致馒头老化的重要原因,馒头心部的老化变硬比表层老化变硬滞后。     

Analysis of Volatile Compounds in Shochu Koji,Sake Koji,and Steamed Rice by Gas Chromatography‐Mass Spectrometry

The volatile compounds in three types of koji (yellow, white, and black) and steamed rice were investigated using gas chromatography‐mass spectrometry. The objective of this study was to characterize each koji type based on its profile of volatile compounds. From the steamed rice and rice koji samples examined, a total of 29 volatile compounds were identified. Butanal, hexanal, dimethyl trisulfide and cyclohexyl isothiocyanate were detected only in steamed rice. The volatile profile of yellow koji (sake koji) was distinct from those of white and black kojis (shochu koji). On the basis of relative peak areas, alcohols and aldehydes were identified as being more abundant in yellow koji. White and black kojis had similar volatile profiles, and had a greater abundance of furans than yellow koji. We assume that the different suites of volatile compounds identified in shochu and sake kojis impart the respective characteristic flavours to shochu and sake.     

陈窖豆豉粑类黑精组分体外抗氧化活性研究

药食资源中天然存在的抗氧化活性物质对人体健康的保护作用被日益关注。发酵期18个月的陈窖豆豉粑类黑精的不同组分,经体外抗氧化活性实验表明,粗提物(DCBM)及其S-8树脂粗分组分(DCBM-W和DCBM-E)均显示出一定的抗亚油酸氧化能力,样品浓度为100μg/mL时,活性强于VC,低于BHT,其中DCBM-E可达BHT的1/2,并且DCBM-E经ODS-AQ反相C18柱分离后,其还原力[、DPPH]和[.OH]自由基清除能力虽不及BHT或VC,但组分间差异较大,进一步分离纯化可望筛选到抗氧化活性极强的化合物。     

复配杂粮馒头营养分析及稳定人体血糖效果研究

以小麦粉、黄豆粉、糙小米粉、杏仁粉、玉米粉、燕麦粉和谷朊粉为原料,制备一种营养相对均衡复配杂粮馒头.通过对其营养分析和餐后人体血糖值测定,结果表明:复配杂粮馒头营养均衡指数0.47,营养均衡性优于小麦馒头(INB =0.72),与血糖密切相关的碳水化合物和淀粉含量较低;与葡萄糖和小麦馒头比较,进食复配杂粮馒头后血糖升高...     

Comparison of Two Small-Scale Processing Methods for Testing Silken Tofu Quality

In developing a simple, reliable, small-scale method to assess silken tofu quality in our soybean improvement program, we examined two processing methods and two coagulants, glucono-δ-lactone (GDL) or nigari (magnesium chloride) in two experiments. Silken tofu was prepared from a commercial soybean variety (expt 1) or seven soybean varieties (V1–V7) which were grown and harvested together (expt 2). The soybeans were soaked overnight (the soak method, with 55 g soybeans) or ground dry first (the dry method, with 60 g soybeans) before processing. The quality of the silken tofu was evaluated and compared among varieties and coagulant-processing methods and their interactions. Moisture and protein content in soymilk and soybean seeds, soymilk yield and protein and solid recovery in soymilk were determined. Compared with the dry method, the soak method allowed faster soymilk extraction, produced soymilk with lower solid and higher protein content and firmer silken tofu with either GDL or nigari as coagulant. Depending on whether nigari or GDL was used as coagulant, the soak method also produced silken tofu with the highest or the lowest water loss which correlated strongly and negatively with tofu hardness (r?=??0.93***). Differences were detected among varieties for the key quality attributes. Taken together, the soak method with GDL as coagulant would be the preferred combination to use to assess tofu quality.