采后钙处理对香菇多糖和细胞稳定性的影响

以采后香菇子实体为原料,采取CaCl2溶液真空渗透法,研究Ca2+处理对采后香菇多糖、β-1,3-葡聚糖酶活性、膜透性和MDA的影响。结果表明：0.12mol/L CaCl2处理的效果最好,β-1,3-葡聚糖酶活性为20.54U/mg,香菇多糖含量为0.38%,膜电导率为85.11%,MDA含量为2.48μmol/L,均优于对照。不同浓度Ca2+处理均能抑制香菇采后β-1,3-葡聚糖酶活性,降低香菇多糖贮藏期间的损耗,并有效维持细胞膜结构的完整性。     

明矾替代物生产马铃薯淀粉粉丝的研究

传统加工生产粉丝时均加入含铝物质-明矾,铝摄入过量对人体有害。试验采用绿豆淀粉、魔芋粉和复合磷酸盐3种物质替代明矾,并通过测定粉丝的断条率和烹煮损失率分析了替代物对粉丝质量的影响。结果表明,绿豆淀粉对粉丝质量有一定改善作用,添加4%～6%的绿豆淀粉、0.4%～0.6%的魔芋粉和0.4%～0.6%的复合磷酸盐能明显改善无明矾马铃薯淀粉粉丝的品质。正交试验表明,以断条率为指标各因素影响大小次序是B>C>A;以烹煮损失率为指标各因素影响大小次序是A>C>B,结合试验结果、生产工艺和产品经济效益,以A1B2C3为最佳组合。断条率为6.7%;烹煮损失率为7.2%。其品质接近或超过传统添加明矾的粉丝。     

发酵布丁豆腐生产工艺的研究

本实验通过在豆浆中添加葡萄糖酸-δ-内酯(GDL)和CaCl2并利用乳酸菌发酵生产一种新型的布丁豆腐,其质地细腻、营养丰富、富有弹性,并具有独特的豆香味。采用正交试验确定最佳的发酵工艺条件为:发酵温度40℃、发酵时间5h、接种量4%,并通过单因素试验确定GDL和CaCl2的最佳添加量为:0.2%和0.05%。     

凝固剂对热改性SPI与猪肌肉盐溶蛋白共凝胶作用的影响

本文研究通过单因素实验和正交实验研究凝固剂葡萄糖酸-δ内酯(GDL)、CaCl2、MgCl2和复合凝固剂对改性大豆分离蛋白(SPI)与猪盐溶蛋白(SSPP)共凝胶的影响。结果表明,GDL对蛋白质共凝胶具有破坏作用,而CaCl2、MgCl2对共凝胶均有促进作用。蛋白质混合凝胶形成的最佳条件为:加热时间20min、CaCl2与MgCl2分别为0.3%、温度95℃、m(SSPP):m(SPI)=7:3。     

超声辅助冻融法提取燕麦麸β-葡聚糖

为探究燕麦麸中β-葡聚糖的超声辅助冻融提取方法,采用超声浸提、蒸发浓缩、反复冻融从燕麦麸中提取β-葡聚糖,研究燕麦麸β-葡聚糖的提取得率、纯度、持水性和黏度,同时用紫外和红外光谱对提取的燕麦麸β-葡聚糖进行结构表征。结果表明:超声辅助提取时,当料液比为1∶20(g/mL)、超声功率为500 W、提取温度为55℃、提取时间为50 min,可将提取液蒸发浓缩至体积的4.0%,反复冻融2次,燕麦麸β-葡聚糖的得率为6.0%,β-葡聚糖纯度可达到82.3%,其持水率为307.6%,燕麦麸中提取的β-葡聚糖紫外光谱、红外光谱和β-葡聚糖的标准图谱一致。超声辅助冻融法提取可得到较高纯度、持水率和黏度的燕麦麸β-葡聚糖。     

淀粉液化芽孢杆菌产β-葡聚糖酶培养基优化以及酶稳定剂的研究

采用正交试验方法,进行了淀粉液化芽孢杆菌发酵产β-葡聚糖酶培养基的优化。结果表明,采用玉米粉30g/L,大麦粉40g/L,豆饼粉30g/L,Na2HPO4.12H2O 6g/L,(NH4)2SO4 4g/L,CaCl2 0.8g/L,MgSO4.7H2O1g/L组成的培养基发酵,β-葡聚糖酶活力达到128.55U/mL,比优化前提高了22.48%。在β-葡聚糖酶溶液中添加大分子亲水型多糖黄原胶、动物蛋白明胶、甘油、氯化钠可明显提高β-葡聚糖酶的热稳定性。将添加甘油120g/L、黄原胶5g/L复合稳定剂的葡聚糖酶溶液60℃处理2h,酶液的残余酶活比未经处理的酶活提高了55.3%。     

无矾淮山药红薯粉丝的研制

以淮山药粉、红薯淀粉为主要原料,研制一种无矾新型粉丝。以粉丝的感官评分、断条率和糊汤吸光度作为试验指标进行单因素试验,考察淮山药粉、海藻酸钠、复合磷酸盐对红薯粉丝品质的影响。并通过正交试验得出粉丝最佳配方。结果表明:当淮山药粉8%、海藻酸钠0.5%、复合磷酸盐0.4%时,粉丝品质最佳,其感官评分为91.20,断条率为8.33%,糊汤吸光度为0.101。该配方生产的粉丝品质较高,为进一步生产淮山药无矾粉丝提供了理论依据。     

明矾替代物对甘薯粉丝品质的影响

多数粉丝在加工时均加入了含铝物质-明矾,但铝摄入过量对人体有害.试验从多种添加剂中筛选出三种明矾替代物-玉米淀粉、复合磷酸盐和黄原胶,并通过测定粉丝的断条率、糊汤情况及膨润度分析了替代物对粉丝质量的影响.结果表明,添加0.3%明矾可显著改善粉丝断条率和糊汤情况;玉米淀粉对粉丝质量有一定改善作用,添加4.0%甘薯粉丝质量达到最佳;添加0.40%～0.50%的复合磷酸盐或0.3%的黄原胶均能显著改善甘薯粉丝的品质.正交试验表明,添加4%的玉米淀粉、0.5%的复合磷酸盐和0.3%的黄原胶对粉丝质量有很显著的改善作用,其质量接近于添加了0.3%明矾的粉丝.     

淀粉液化芽孢杆菌5582产β-葡聚糖酶的发酵条件和酶学性质研究

报道了淀粉液化芽孢杆菌(Bacillusamyloliquefacien)BS5582菌株产β-葡聚糖酶和蛋白酶的液体发酵条件优化和酶学特性的研究结果。摇瓶水平下产β-葡聚糖酶的最佳培养基(g/L)为大麦粉40,玉米粉30,豆饼粉30,Na2HPO4·12H2O6,(NH4)2SO44,MgSO·47H2O1,CaCl20.8;产酶最佳起始pH7.0,装液量25mL/250mL。种子于37℃培养10h后,接种量8%,在37℃下发酵51.75h后β-葡聚糖酶酶活最高达到182.52U/mL,蛋白酶酶活达8062U/mL。β-葡聚糖酶的最佳反应pH6.5,最佳反应温度50℃。10mmol/L的Ca2 、Na 、NH4 、K 、Mg2 对β-葡聚糖酶活性有一定的激活作用;而相同浓度的Cu2 、Fe2 则表现出较强的抑制作用。     

降低粉丝断条率的循环清水煮粉技术及装置

断条率是评价粉丝食用品质和商品价值的关键指标。采用循环清水煮粉技术及装置,热水流经射流装置对粉丝进行冲刷梳理煮制后,通过排污装置净化,循环利用。不仅自动化程度高,而且提高了粉丝品质,降低了生产成本。试验结果表明:循环清水煮粉技术与传统钢锅煮粉方法相比,粉丝断条率降低55%,一等品率提高11.3%,得率提高7.9%;单位热耗降低58%,耗水量减少39%。     

响应面法优化啤酒酵母泥中β-1,3-葡聚糖提取工艺

为提高啤酒酵母泥中β-1,3-葡聚糖的得率,采用响应面法优化酸碱法提取葡聚糖的工艺条件,对NaOH质量分数、碱提温度、碱提时间3个因素进行单因素试验。根据单因素试验结果,设计中心组合试验,以葡聚糖得率为指标,采用响应面分析法确定最优工艺参数。结果表明：在NaOH溶液质量分数2.05%、92.70℃处理2.50h条件下,β-1,3-葡聚糖得率实测值为15.76%,模型预期值为15.82%,响应面优化法提高了β-1,3-葡聚糖的得率。     

A new approach for the utilization of barley in food products: Barley tarhana

One hulless and two hulled barley samples were used to produce tarhana samples with relatively high β-glucan content. Chemical and sensory properties of the tarhana samples were investigated and compared with the traditional wheat tarhana. Although some of the β-glucan may be destroyed during fermentation, the results indicated that barley flours can be used to produce tarhana with relatively high β-glucan content. Effect of tarhana production on the electrophoretic properties of proteins was evaluated in this study by using SDS–PAGE. Relative band intensities of tarhana samples were generally less intense than those of respective flour samples probably due to the hydrolysis of proteins during fermentation. The use of barley flours affected the color and RVA soup index values of tarhana samples. However, the overall sensory analysis results indicated that utilization of barley flours in tarhana formulation resulted in acceptable soup properties in terms of most of the sensory properties.     

加热即食方便豆腐脑产品的开发

采用豆粉冲调、均质、添加凝固剂和85 ℃水浴加热15 min的方式制作即食豆腐脑。研究了不同添加量的葡萄糖酸-δ-内酯（GDL）、氯化钙和氯化镁对制作的即食豆腐脑特性的影响。结果表明,GDL、氯化钙和氯化镁单一使用时,添加量分别在0.50%、0.30%和0.40%时豆腐脑产品凝胶效果较好。在对以上3种凝固剂进行不同比例复配,从质构特性和感官评价两方面确定了GDL、氯化钙、氯化镁的复配比例在10∶2∶3时开发的即食新产品相较于单一使用凝固剂和其他3种复配比例有显著优势（P＜0.05）。     

Factors influencing consumers’ willingness to use beverages and ready-to-eat frozen soups containing oat β-glucan in Finland,France and Sweden

Factors affecting consumers’ willingness to use beverages and ready-to-eat frozen soups containing oat β-glucan were studied in Finland, France and Sweden (N = 1157).Three beverage or soup samples were presented to each consumer: a reference sample without β-glucan/health claim, a sample containing β-glucan, without claim and a third one with β-glucan and claim (cholesterol or glucose related). Questions about liking, beneficiality, willingness to use and price estimates for purchasing were asked before and after tasting. A trained sensory panel (N = 11) also profiled the sensory characteristics of the samples.Taste of the samples strongly affected the willingness to use them. Health claim gave a significant but small added value to beverages and soups with β-glucan. The price respondents were willing to pay for the beverages and soups containing β-glucan decreased after tasting, regardless of the health claim. No notable effect due to gender or age on the willingness to use products with health claims was found.     

Effect of barley β-glucan on murine RAW264.7 macrophages against virulent Salmonella enterica serovar Typhimurium

Heavily evidenced in antimicrobial effects of microbial β-(1,3)(1,6)-glucan, the botanical β-(1,3)(1,4)-glucan is mostly shown to effectively control blood cholesterol level. S. Typhimurium belongs to food-borne zoonoses often causing worldwide epidemic outbreaks in animals and human with severe diarrhea and gastrointestinalitis. Cereal soups are commonly prescribed as neutraceutical for rehydration purpose and a sustaining therapy. Botanical β-(1,3)(1,4)-glucan is easily released in boiled cereal soup. β-(1,3)(1,4)-Glucans on modulating host defense to enteric infectious agents is seldom reported. Our results demonstrated that barley β-(1,3)(1,4)-glucans effectively increased the murine macrophage cell line RAW264.7 against S. Typhimurium infection through antibacterial lysozyme activity (P < 0.001), not the production of intracellular reactive oxygen species. Furthermore, barley β-(1,3)(1,4)-glucans upregulated the gene expressions of its receptor dectin-1. In conclusion, barley β-(1,3)(1,4)-glucan induces a mild immune response with increasing antibacterial lysozymes through up-regulating its receptors dectin-1 and lysozyme M gene expressions.     

发芽处理对青稞β-葡聚糖抗氧化和抗炎作用的影响

本文对青稞进行发芽处理,主要探究发芽过程对其β-葡聚糖含量、分子量、抗氧化及抗炎作用的影响。实验结果表明:发芽过程中,β-葡聚糖的含量总体呈现先上升后下降的趋势,分子量从275.74 kDa持续降至114.63 kDa;和未发芽青稞β-葡聚糖相比,FRAP值、DPPH自由基和ABTS自由基抑制率等三项体外抗氧化能力测定指标分别上升了35.63%、248.64%、80.57%;此外,通过建立脂多糖(LPS)诱导结肠癌细胞(Caco-2)炎症模型发现,发芽青稞β-葡聚糖能明显提高细胞存活率,减少炎症因子肿瘤坏死因子(TNF-α)、白细胞介素-6(IL-6)和促炎因子前列腺素E2(PGE₂)、一氧化氮(NO)的分泌水平,降低丙二醛(MDA)生产量并增加超氧化物歧化酶(SOD)、谷胱甘肽(GSH)含量从而改善细胞炎症期间的氧化应激水平。综上得出,发芽处理能显著增强青稞β-葡聚糖抗氧化和抗炎作用,从而缓解肠道在炎症受到的损伤。     

苯酚-硫酸法测定β-葡聚糖含量研究

分别以β-葡聚糖和葡萄糖为标准品测定青稞提取物中β-葡聚糖含量。以β-葡聚糖为标准品时,线性浓度范围在6～13μg/mL,回归方程为y=0.0445X-0.0071,回归系数为R2=0.9568,青稞中提取β-葡聚糖粗提物纯度为22.3%(脱脂)和10.7%(未脱脂);以葡萄糖为标准品时,线性浓度范围在0-21μg/mL,回归方程为y=0.0588X+0.0326,回归系数为R2=0.9934,青稞中提取出β-葡聚糖粗提物纯度为12.5%(脱脂)和4%(未脱脂),二者之间测定结果有78.4%左右误差。在β-葡聚糖含量测定过程中不能用葡萄糖代替β-葡聚糖作标准品,用β-葡聚糖作标准品时苯酚-硫酸法工作曲线线性回归性不强,直接用苯酚-硫酸法测定β-葡聚糖方法不可取。     

基于人体必需金属盐替代的低钠盐肌原纤维蛋白凝胶特性和作用机理

为降低肌原纤维蛋白凝胶中钠盐的使用量,研究不同氯盐(CaCl₂、MgCl₂、KCl)部分替代NaCl对肌原纤维蛋白凝胶性质包括强度、微观结构、持水力和流变学性质的影响,并通过十二烷基硫酸钠-聚丙烯酰胺凝胶电泳、内源性荧光光谱、表面疏水性、巯基含量等技术手段阐明其作用机理。结果表明,3种氯盐替代效果排序为KCl>CaCl₂>MgCl₂。0.5%～1.5%质量分数的盐替代范围内,KCl替代组的凝胶强度优于对照组(3%NaCl),持水力与对照组相比无显著差异(P>0.05);Ca Cl₂替代组的凝胶强度在1.5%替代质量分数时显著下降(P<0.05),持水力呈先下降后上升趋势;MgCl₂替代组凝胶强度显著降低(P<0.05),持水力上升。在流变学性质方面,不同质量分数KCl替代组的储能模量明显高于对照组。CaCl₂和MgCl₂的替代使肌原纤维蛋白表面疏水性增大、巯基含量减少,3种氯盐的替代...     

High molecular weight barley β-glucan decreases particle breakdown in chapattis (Indian flat breads) during in vitro digestion

The influence of high molecular weight barley β-glucan on particle breakdown in chapattis during in vitro starch digestion was investigated in this study. Chapattis with 0%, 4% and 8% β-glucan were prepared by mixing whole-wheat flour with commercially available β-glucan enriched barley flour (Barley Balance?). There was an inverse relation between the rate of in vitro starch digestion and amount of β-glucan in chapattis. The rate of starch digestion was influenced by the ability of chapattis to resist particle breakdown. Viscosity of the digests increased with increase in amount of β-glucan in the chapatti samples and this effect was more pronounced in the absence of pancreatin. It may be concluded that this increase in viscosity and the putative increase in undigested chapatti fragments resulting from the presence of β-glucan therein might have reduced the rate of in vitro starch digestion.