The impacts of interaction between proanthocyanidin (PC) and decolorized highland barley protein (DHBP) at pH 7 and 9 on the functional and conformational changes in DHBP were investigated. It was shown that PC strongly quenched the intrinsic fluorescence of DHBP primarily through static quenching. PC and DHBP were mainly bound by hydrophobic interactions. Additionally, free sulfhydryl groups and surface hydrophobicity obviously decreased in DHBP after combining with PC. The zeta potential of DHBP–PC complexes at pH 7 increased significantly. A change in the structure of DHBP was caused by interactions with PC, resulting in an increase in the number of β-sheets, a decrease in the number of α-helixes, and a spectral shift in the amide Ⅱ band. Furthermore, the presence of PC enhanced the foaming properties and antioxidant activity of DHBP. Overall, this study suggests that DHBP–PC complexes at pH 7 could be designed as a stable additive, and illustrates the potential applications of DHBP–PC complexes in the food industry.

选用青稞为原料,在固态发酵条件下,研究青稞接种从毛红曲霉(Monascus pilosus)后发酵过程中不同因素对Monacolin K产量的影响.对不同培养基配方及发酵条件等进行单因素试验优化,并以发酵温度、接种量和初始pH值为影响因素,确定产Monacolin K的青稞功能红曲的最优发酵工艺条件.结果表明,以pH4.0的水浸泡至无白心后蒸煮20min的青稞米为基础培养基,添加0.6％蛋白胨、0.3％酵母提取物和0.3％磷酸二氢钾,装料量160 g/500mL,接种10％从毛红曲菌液体菌种,变温发酵,32℃发酵2d后降温至25 ℃发酵21 d.此优化条件下Monacolin K产量可达1.52％.

以昆仑15号、黑老鸦青稞、瓦蓝青稞为研究对象,利用分层碾磨技术,将青稞籽粒由外至内分离出七部位粉.对七部位粉的理化指标进行分析,并采用隶属函数法与主成分分析相结合的方法对各部位粉的营养价值进行了综合评价.结果表明,青稞中的灰分、蛋白质、脂肪、多酚和原花青素含量随籽粒由外至内逐层递减,β-葡聚糖含量在第二、第三部位达到最大值.因此,根据营养成分含量分布情况推测第一部位为青稞粉皮层,第二、三部位为糊粉层,第四至第七部位为胚乳层.隶属函数和主成分分析结果表明,在本实验中获得的七部位青稞粉中,第二部位的青稞粉营养价值最高,尤其是蛋白质含量最高.

为明确青海不同品种黑青稞的营养及化学成分含量,筛选优异种质资源,本研究开展了12种黑青稞营养及化学成分分析与评价.结果 表明,参试黑青稞蛋白、总淀粉、直链淀粉、粗脂肪、粗纤维、灰分、β-葡聚糖含量在部分品种间存在显著差异(P＜0.05),黑青稞具有较高含量的蛋白质(12.19％ ～14.07％)、纤维(2.13％～3.64％)、直链淀粉(18.96％ ～25.94％)和β-葡聚糖(3.91％～7.50％);参试黑青稞中Ca、K、Zn含量存在品种间显著差异(P＜0.05),其余测定的矿物质含量存在部分品种间显著差异(P＜0.05),其中K(581.42 mg· 100g-1)、Mg(171.90 mg· 100g-1)、Ca(90.28 mg· 100g-1)、Na(17.33 mg·100g-1)含量较高;参试黑青稞蛋白中总必需氨基酸含量平均值为319.90 mg·g-1(接近WHO/FAO推荐值360 mg· g-1),第一限制性氨基酸为赖氨酸,第二限制性氨基酸为甲硫氨酸和胱氨酸,第三限制性氨基酸为苏氨酸;参试部分黑青稞品种的总酚、游离酚、结合酚、总黄酮、游离黄酮、结合黄酮及花色苷含量存在显著差异(P＜0.05);主成分筛选出950、Z536、Z533黑青稞综合品质较优,聚类分析将12个黑青稞品种分为4类,第1类蛋白质、多酚、黄酮、β-葡聚糖含量较高;第2类花色苷、氨基酸含量较高;第3类纤维含量较高;第4类淀粉含量较高.本研究结果为黑青稞营养功能品质评价及加工利用奠定了基础,也为特异青稞资源的筛选提供了参考.

通过人体试验检测和评价了青稞全粉含量≥51％挂面的血糖生成指数(Glycemic index,GI).结果表明,以葡萄糖为参考(GI值以100计),受试者食用青稞挂面后,血糖值在餐后15 min和30 min 2个时间点具有统计学差异;青稞挂面的GI值为53.63,血糖负荷(Glycemic load, GL)值为5.37.根据GI值等级划分标准,青稞挂面GI＜55,属低GI食物,表明青稞全粉挂面可以有效控制血糖平衡.

以肚里黄青稞为原料,采用气相色谱-质谱联用技术结合香气分析研究炒制时间及炒制方式对青稞挥发性物质的影响.结果表明:随着炒制时间的延长,挥发性物质种类和含量不断增加,风味物质以杂环类化合物为主,在炒制时间8 min时其相对含量最高达到46.09％.传统先炒后粉的加工方式较先粉后炒得到的杂环类化合物种类更为丰富,特征焙炒香气更为突出.不同炒制时间及方式共有峰为21个,其中杂环类化合物中的吡嗪类物质是炒制青稞最具代表性的香气成分.随着炒制时间的延长,青稞香气由原籽粒的水果香、草香、花香和较弱的油脂香转变为可可香、烤香、坚果香及较少果香为主的典型炒制香气.根据聚类分析和主成分分析结果可知,炒制8 min和11 min相似度较高,表示其香气组成和含量较为一致,但炒制8 min的杂环类化合物含量最高,因此8 min可作为最适宜青稞炒制加工时间.本研究可为青稞焙炒食品开发提供一定理论依据.

近几年城市绿化工作取得了令人瞩目的成绩,基本形成了以街头绿地、庭院绿地为点,以道路绿化、造景绿化为线,以公园、广场等大型绿地为面,与城郊风景林地、遗址公园相结合,"点上绿化成景,线上绿化成荫,面上绿化成林,环上绿化成带",点、线、面、环相街接的综合绿地系统.通过分析著名的古都西安市城市绿化现状,对今后城市绿化提升提出了几点对策研究.

采用α-淀粉酶酶解速溶无麸质复合谷物粉,在单因素试验的基础上,选择淀粉酶添加量、酶作用温度、酶作用时间,进行三因素三水平Box-Behnken试验设计,采用响应面法分析3个因素对响应值(糖度)的影响,从而对速溶无麸质复合谷物粉的酶解工艺参数进行优化.结果表明:淀粉酶添加量0.1％、酶作用时间3.3 h、酶作用温度65℃为最优酶解工艺,其预测I糖度为9.09 Brix,实测糖度为9.07 Brix,两者基本相符,说明回归方程与实际情况拟合度好.

以感官评价为指标研究开发高原皮燕麦茶并通过气相色谱-质谱联用仪(GC-MS),对皮燕麦茶关键工艺参数进行优化研究,对其主要风味物质的成分进行检测初探,研究香气物质的成分类型,确定香气物质的相对含量.结果表明:皮燕麦茶的最优工艺条件为第一阶段焙炒温度为130℃,焙炒时间11 min,第二阶段焙炒温度为180℃,焙炒时间25 min,在此条件下制得的皮燕麦茶的香气、滋味、冲泡性达到最优.通过气相色谱-质谱技术对其香气物质进行检测分析,共检测出56种香气成分,含量较高的组分主要为醛类和吡嗪,这两类香气物质占总香气物质的55.3％,其中,醛类物质共有16种,占香气物质的32.09％;含氮类物质吡嗪有9种,占香气物质的23.21％.

青稞经过发芽后食用品质和营养价值发生了很大的变化,具有良好的发展前景.本文综述介绍青稞在发芽前后其主要理化营养指标的研究变化进展情况,根据原料特点提出了青稞发芽食品的开发思路,为青藏高原青稞产业创新发展提供建议.

研究了HACCP质量控制体系在青稞即食糌粑生产中的应用,根据生产工艺流程,对各工序经行了详尽的危害分析,并提出了相应控制措施.

以青藏高原优质有机青稞为主要原料,通过分段式焙炒技术得到青稞全籽粒麦茶,并与青藏高原出产的枸杞、绿萝花、雪菊、玫瑰花等进行复配,研发出了具有不同保健功效的青稞袋泡茶系列产品.通过正交试验确定了炒制青稞麦茶的工艺条件为:第一阶段:150℃,15 min;第二阶段:180℃,20 min;第三阶段:200℃,5 min;青稞菊杞茶最优配比为:枸杞6％、昆仑雪菊1.6％、玫瑰花3％、柠檬草0.4％;青稞绿萝茶最优配比为:绿萝花10％、七彩菊30％.

硒是人体必需的微量元素之一,元素硒对人体有重要的生理功能.介绍国内富硒食品的开发现状及重要性,指出我国富硒食品的发展方向.

Sucrose fatty acid ester,gellan gum,sodium hexametaphosphate and sodium tripolyphosphate were compounded to give compound aging resisters of original starch in cereal beverages of highland-barley and purple rice.The optimal dosages of the components were determined as follows:sucrose fatty acid ester 1.1 g/L,gellan gum 0.11 g/L,sodium hexametaphosphate 0.13 g/L and sodium tripolyphosphate 0.084 g/L.The shelf life of the beverages exceeded 10 months.Sensory evaluation,physicochemical testing and microbiological examination indicated that the key indicators of the beverages were all up to the related national standards.

The optimal additive dose of compound age resister of original starch in compound cereal beverage of highland-barley has been selected,the best proportion was obtained as follows:Sucrose fatty acid ester1.3 g/L,gellan gum 0.127 g/L,sodium hexametaphosphate 0.12 g/L,sodium tripolyphosphate 0.05 g/L,shelf life of the beverage exceed ten months.By sensory analysis,physical and chemical testing and microbiological examination.The key indicator of the beverage meet related regulation of National Standards(GB).

A new kind of compound cereal protein beverage was studied and developed with highland-barley and soybean as the main raw materials,with the addition of Qinghai medlar,honey,etc. The optimum technological parameters and formula were determined through experiments. The results of physicochemical tests indicated that the beverage had high nutritional value. After sensory evaluation,it was agreed that the compound cereal protein beverage,with or without sugar added,was characterized by the special flavor of highland-barley,and nice color and taste.

A compound cereal beverage was made from highland-barley - a characteristic plateau crop,with the addition of liquid extracts of soybean,purple rice and black sesame. Through orthogonal experiments,the optimum formula was determined as follows: soybean milk 50 ml,highland-barley juice 115 ml,purple rice-black sesame juice 70 ml and sugar 3.5%. The beverage had strong cereal aroma and high nutritional value.