萌动青稞玫瑰绿茶的工艺研究及营养成分分析

为开发高附加值青稞产品,以萌动青稞为主要原料,辅以干玫瑰花和绿茶,采用单因素和正交试验对萌动青稞玫瑰绿茶的制备及工艺进行优化,并对其营养组成进行分析。通过感官评价得到萌动青稞玫瑰绿茶的最佳制备工艺为:烘烤温度200℃,烘烤时间8 min,萌动青稞添加量70%(质量分数),此工艺下萌动青稞玫瑰绿茶的感官评分为90.23分。相比于青稞茶和萌动青稞茶,萌动青稞玫瑰绿茶茶粉及茶汤中总酚、黄酮和γ-氨基丁酸(γ-aminobutyricacid,GABA)的含量显著升高,蛋白质、膳食纤维、β-葡聚糖和淀粉的含量有所降低。     

萌动青稞米酒的工艺研究及理化性质分析

为促进中国青稞产业的发展,开发高附加值青稞产品。以萌动青稞为原料,采用单因素试验和正交试验进行萌动青稞米酒的制备及工艺优化,并分析其营养组成和香气成分。以感官评价为基础,通过测定酒精度、糖度和酸度,得到萌动青稞米酒的最佳制备工艺:甜酒曲添加量0.8%,培养时间60 h,培养温度28℃。相比于青稞米酒,萌动青稞米酒中总酚、黄酮和γ-氨基丁酸(GABA)含量明显高,蛋白质、膳食纤维、β-葡聚糖和淀粉含量低。萌动青稞米酒中检测出102种挥发性化合物,以醛类、醇类、酯类物质化合物为主。试验结果丰富了青稞产品种类,对青稞新型饮品的开发具有一定指导意义。     

青稞发芽过程中β-葡聚糖、γ-氨基丁酸和多酚的含量研究

研究青稞中β-葡聚糖、γ-氨基丁酸和多酚三种活性物质的含量随萌动温度和时间的变化。以康青7号、独立花、紫青稞、藏青25号和西藏2000五个青稞品种做萌动实验,分别采用葡萄糖氧化酶-过氧化酶法(Glucose oxidase/peroxidase method,GOPOD)、高效液相色谱法(High Performance Liquid Chromatography,HPLC)、福林酚法检测不同萌动温度和时间条件青稞中的β-葡聚糖、γ-氨基丁酸和多酚含量。结果表明,三类物质在不同品种内随萌动时间的变化趋势不完全相同,三者的变化无显著性相关;β-葡聚糖含量在青稞萌动后下降,γ-氨基丁酸萌动后增加,多酚含量在不同品种中有不同的变化。萌动前,三类物质在藏青25号中的含量最高;萌动后,与相同萌动时间段的其他品种相比,β-葡聚糖在藏青25号中的含量最高,γ-氨基丁酸在藏青25号和西藏2000中的含量较高,多酚在康青7号中含量较高;萌动温度为22℃时,康青7号87 h、西藏2000萌动27 h,紫青稞和藏青25号萌动39 h,可以得到四种萌动青稞中三类物质较佳含量;而独立花青稞不适合做萌动处理。     

青稞萌动过程中β-葡聚糖、γ-氨基丁酸和多酚的含量研究

研究青稞中β-葡聚糖、γ-氨基丁酸和多酚三种活性物质的含量随萌动温度和时间的变化。以康青7号、独立花、紫青稞、藏青25号和西藏2000五个青稞品种做萌动实验,分别采用葡萄糖氧化酶-过氧化酶法(Glucose oxidase/peroxidase method,GOPOD)、高效液相色谱法(High Performance Liquid Chromatography,HPLC)、福林酚法检测不同萌动温度和时间条件青稞中的β-葡聚糖、γ-氨基丁酸和多酚含量。结果表明,三类物质在不同品种内随萌动时间的变化趋势不完全相同,三者的变化无显著性相关;β-葡聚糖含量在青稞萌动后下降,γ-氨基丁酸萌动后增加,多酚含量在不同品种中有不同的变化。萌动前,三类物质在藏青25号中的含量最高;萌动后,与相同萌动时间段的其他品种相比,β-葡聚糖在藏青25号中的含量最高,γ-氨基丁酸在藏青25号和西藏2000中的含量较高,多酚在康青7号中含量较高;萌动温度为22℃时,康青7号87 h、西藏2000萌动27 h,紫青稞和藏青25号萌动39 h,可以得到四种萌动青稞中三类物质较佳含量;而独立花青稞不适合做萌动处理。     

膨化萌动青稞粉油茶的制备及其品质评价

以萌动青稞粉为原料,通过双螺杆挤压膨化技术制得膨化青稞粉。研究物料水分含量、螺杆转速和挤压温度对膨化萌动青稞粉吸水性指数和水溶性指数的影响,通过单因素和正交试验,确定最佳工艺参数为:物料水分含量为26%、螺杆转速为220 r/min、挤压温度为180℃。在传统油茶制作的基础上研制新型膨化萌动青稞粉油茶,主要考察了膨化萌动青稞粉添加量、花生油添加量、炒制温度、炒制时间对青稞粉油茶溶解度指数和感官评分的影响,通过单因素和正交试验,确定最优工艺配方为:青稞粉添加量为68%、花生油添加量为4%、炒制温度60℃、炒制时间为6 min。此时,油茶感官评分为9.26分,具有高蛋白、高膳食纤维、低脂肪和低钠等特点。     

不同热加工对萌动青稞营养成分和加工特性的研究

本文研究了干热熟制、微波熟化、挤压膨化三种热加工方式对萌动青稞萌动青稞营养成分与加工特性的影响。结果表明,不同热加工后的萌动青稞粉总膳食纤维、β-葡聚糖、总酚等含量均有所提高。对照组萌动青稞与不同热加工粉色度存在很大差异,其中挤压膨化对色度影响最大;扫描电镜结果显示,三种热加工方式均使淀粉颗粒遭到一定程度的破碎,其中挤压膨化粉的淀粉颗粒分布的更加紧密,糊化的更完全。在100 ℃时,挤压膨化粉吸水指数、膨胀势均最高,干热熟制粉的水溶性最高;三种热加工粉的峰值黏度、谷值粘度、衰减值、最终黏度、回生值、糊化温度及热焓值均升高。综合试验结果,挤压膨化更利于萌动青稞粉工业化生成。     

不同热加工对萌动青稞营养成分和加工特性的影响

研究干热熟制、微波熟化、挤压膨化3种热加工方式对萌动青稞营养成分与加工特性的影响。结果表明,不同热加工后的萌动青稞粉总膳食纤维、β-葡聚糖、总酚等含量均有所提高。对照组萌动青稞与不同热加工粉色度存在很大差异,其中挤压膨化对色度影响最大;扫描电镜结果显示,3种热加工方式均使淀粉颗粒遭到一定程度的破碎,其中挤压膨化粉的淀粉颗粒分布的更加紧密,糊化也更完全。在100℃时,挤压膨化粉吸水指数、膨胀势均最高,干热熟制粉的水溶性最高;3种热加工粉的峰值黏度、谷值黏度、衰减值、最终黏度、回生值、糊化温度及热焓值均升高。综合实验结果,挤压膨化更利于萌动青稞粉工业化生产。     

青稞营养成分研究进展及其应用现状

近年来,种植于青藏高原的青稞日益受到国内外学者的青睐。青稞中含有的淀粉、蛋白质、β-葡聚糖、脂质、微量元素、维生素以及多酚等营养物质对于人体的肥胖、高血糖、高血压、高血脂以及癌症等疾病均有积极作用。然而,目前青稞的利用主要基于整个谷物,忽略了青稞各组分的应用潜能。鉴于此,分别对青稞不同组分的性质和应用进行总结和归纳,以期为青稞产品的全面开发和增值利用提供参考和理论依据。     

青稞功能成分与生物活性研究进展

青稞是一种营养丰富的禾本科植物,食用历史悠久。除具有较高的营养价值外,现代研究表明,青稞富含β-葡聚糖、多酚等功能因子,具有抗氧化、抗肿瘤、降糖、抗心血管疾病等多种生物活性,在食品、保健及相关行业中具有广阔的应用前景,受到了国内外学者的广泛关注。本文总结了青稞已培育的种类和营养品质,以期为青稞的功能与生物活性的研究和开发提供参考和依据。同时重点综述了青稞抗氧化、降血糖、减肥、降血脂、抗动脉粥样硬化、抗血小板凝聚、免疫调节等功能性研究的成果,旨在为功能性食品的开发提供理论依据,继而有助于预防和辅助治疗慢性病。     

黑青稞的营养价值与产品开发分析与展望

黑青稞是青稞的一种,为青藏高原特有作物。随着人们追求营养健康饮食,黑青稞的营养价值和降血糖、降血脂的保健功效愈来愈受到关注。系统地总结与分析了黑青稞的营养成分、主要功能成分及产品开发方向,并对其发展前景进行展望,旨在为黑青稞产业的高质量发展提供一定的参考。     

CELLULASES OF PLANT AND MICROBIAL ORIGIN IN GERMINATING BARLEY

Cellulase activity in crude extracts of germinating barley is at least five-fold higher in hulled than in hull-less cultivars. Surface sterilization of the grain prior to germination reduces cellulase to levels that are similar in all cultivars. In hulled barley most of the cellulase detected during germination is probably of microbial origin, but there is circumstantial evidence to suggest that significant activity can also be attributed to cellulases of plant origin. The micro-organisms associated with germinating grain reside largely in the hull and the major fungal species present on the hulled variety Clipper were Aureobasidium pullulans, Rhizopus stolonifer and Penicillium spp. Surface sterilization of the grain with silver nitrate, followed by steeping in a solution containing antibiotics, completely eliminated microbial growth on hull-less cultivars. After similar treatment of a hulled barley two yeasts could be detected. The results emphasize the importance of eliminating microbial growth prior to studies of polysaccharide hydrolases which develop during the germination of barley and which are assumed to be of plant origin.     

Effects of grain source and enzyme additive on site and extent of nutrient digestion in dairy cows

Four lactating, cannulated Holstein cows were used in a 4 x 4 Latin square design to investigate the effects of grain source and fibrolytic enzyme supplementation on ruminal fermentation, nutrient digestion in the rumen and in the intestine, and milk production. A 2 x 2 factorial arrangement was used; two grains (barley and hull-less barley) were combined with and without enzyme. The enzyme supplement (Pro-Mote; Biovance Technologies Inc., Omaha, NE) contained primarily cellulase and xylanase activities and was applied daily to the total mixed diet. Dry matter intake was not affected by diet, but starch intake was greatest when hull-less barley was fed. Starch from hull-less barley was more digestible in the rumen and in the total tract than was starch from barley, but opposite results occurred for fiber digestion, indicating that hull-less barley depressed fiber digestion. As a result, cows fed the hull-less barley diets tended to produce more milk with a higher milk lactose content than did cows fed the barley diets. Enzyme supplementation had minimal effects on ruminal digestion but increased nutrient digestibility in the total tract and the proportion of microbial N in nonammonia N. Consequently, cows fed diets supplemented with enzyme had a higher milk protein content and tended to produce more 4% fat-corrected milk than did control cows. These results indicate that the use of hull-less barley rather than barley increased the digestible energy intake of dairy cows, resulting in higher milk production. The use of a fibrolytic enzyme mixture enhanced feed digestibility and milk production.     

Technical note: In situ ruminal starch disappearance kinetics of hull-less barley,hulled barley,and corn grains

The objective of this study was to compare ruminal starch disappearance rates of hull-less barley, hulled barley, and corn grains. Five different genotypes were used for each of the 2 barley types. In addition, each of these genotypes was grown in 2 different locations and years, resulting 10 independent barley samples for each of the 2 barley grain types. Five different genotypes of corn grain were obtained from a commercial seed company. After being ground to pass through a 4-mm screen of a cutter mill, 3.6 g of each grain was placed into a porous bag, which was then incubated in the rumen of 2 ruminally cannulated cows for 0, 4, 8, 12, 24, and 48 h. Corn grains had greater instant ruminal starch disappearances than barley grains (22.4 and 8.2%, respectively). Instant ruminal starch disappearances did not differ between hulled and hull-less barley grains. Ruminal starch fractional disappearance rates were greatest for hulled barley grains, moderate for hull-less barley grains, and lowest for corn grains (15.3, 13.9, and 7.1%/h, respectively). Ruminal starch half-life was shortest for hulled and hull-less barley grains (4.4 h) and longest for corn grains (6.6 h). Ruminal starch half-life did not differ between hulled barley and hull-less barley grains. In conclusion, using a holistic experimental design and statistical analysis, this study showed that starch from hull-less barley grains has a ruminal half-life similar to that of hulled barley grains and shorter than that of corn grains.     

Effects of steeping and anaerobic treatment on GABA (γ-aminobutyric acid) content in germinated waxy hull-less barley

Effects of steeping conditions (time, temperature and soaking solution) and anaerobic storage on the gamma-aminobutyric acid (GABA) content in waxy hull-less barley grains during germination was examined. The barley kernel was steeped for 16 h at different temperatures (5, 15 or 35 °C) either in water or in a buffer solution (pH 6.0, 50 mmol/L sodium acetate) and then germinated at 15 °C for 72 h. To reach the optimum water content (36–44 g/100 g) for germination, a longer steeping period was required when steeping temperature was lower (16 h at 5 °C vs. 8 h at 15 °C). At 35 °C for steeping, however, the water content in the grains increased excessively, and thus germination percentage became much less than those at 5 and 15 °C. The GABA content increased with increasing germination time and was higher in the buffer solution than water. These findings indicate that the glutamate decarboxylase (GAD), which is the rate-limiting enzyme for GABA synthesis, is more activated by extending germination at controlled pH (6.0). An anaerobic storage with nitrogen in the dark for the germinated barley grains substantially raised the GABA content: 14.3 mg/100 g after the treatment for 12 h, which was four times higher than that of control sample (3.7 mg/100 g). Overall results suggest that the steeping prior to germination greatly affects the GABA production during the germination of barley, and the anoxia storage with nitrogen after the germination increases the GABA content.     

Hull-less barley for swine: ileal and faecal digestibility of proximate nutrients,amino acids and non-starch polysaccharides

The nutritive value of three hull-less barley cultivars (Condor, Falcon and CDC Buck) were evaluated. The samples were analysed for proximate composition, amino acids and non-starch polysaccharides (NSP). Wheat and normal barley were used for comparison. Apparent digestibilities were determined with eight cannulated pigs. The diets were formulated to have all energy and protein supplied by the cereals. Compared to normal barley, hull-less barley has higher contents of protein and amino-acids, and lower levels of fibre components. The levels of several essential amino acids in hull-less barley are higher than in wheat. No obvious differences in NSP composition were observed, but the hull-less barley contained considerably higher levels of β-glucan compared to hulled barley and wheat. In digestion trials the piglets did not accept the diet in which conventional barley was formulated as the only energy and protein source, whereas hull-less barleys were well consumed. The results showed that, in the order of Condor, Falcon, CDC Buck and wheat, the overall tract digestibilities of intake energy were 83·1, 80·3, 83·2 and 82·9%, and of protein were 72·6, 69·5, 76·5 and 77·6%, respectively. The averages of apparent ileal amino acid digestibility were 56·5, 58·4, 65·3 and 65·4%, respectively. Hull-less barleys showed 20–37% ileal digestibility of total NSP. This study provides digestibility coefficients of hull-less barleys, and it is concluded that the digestibility of hull-less barley is comparable to wheat and superior to hulled barley in terms of nutrient composition and acceptability. © 1998 SCI.     

THE DETERMINATION AND UTILIZATION OF GIBBERELLIC ACID IN GERMINATING BARLEY

A barley endosperm bioassay, utilizing the induction of acid phosphatase in barley endosperm seed halves, has been developed and applied to study both the development of endogenous gibberellin in grain germinating under malting conditions and the utilization of externally applied gibberellic acid. The assay is affected by barley age and variety and these observations may have practical implications. After 24 h germination the level of endogenous gibberellin-like material present in the grain was approximately 1·4 ng/corn. The biological activity of the total gibberellin-like material extracted from grain treated with gibberellic acid fell during germination although significant quantities of applied gibberellic acid had entered the grain during the first 24 h germination.     

IAA,ABA AND GERMINATION OF SPRING BARLEY CARYOPSES DURING POST-HARVEST MATURATION

Changes in the content of indole-3-acetic acid (IAA) and abscisic acid (ABA) were investigated in the caryopses of three spring barley varieties (Alexis, Akcent and Rubin) shortly before harvest and during post-harvest maturation. Simultaneously, the values of the germination index and germinating energy were followed after harvest. The differences in endogenous contents of the phytohormones were determined in the caryopses of all three barley varieties which showed a decreasing pattern during post-harvest maturation while in contrast the values of the germinating energy and germination indices increased. Significant differences were observed between the varieties .     

Effects of feeding hull-less barley on production performance,milk fatty acid composition,and nutrient digestibility of lactating dairy cows

The objectives of this study were to evaluate production performance, milk fatty acid composition, and nutrient digestibility in high-producing dairy cows consuming diets containing corn and hull-less barley (cultivar Amaze 10) in different proportions as the grain source. Eight primiparous and 16 multiparous Holstein cows were assigned to 1 of 4 diets in a replicated 4 × 4 Latin square design with 21-d periods. Cows were fed once daily (1200 h) by means of a Calan gate system (American Calan Inc., Northwood, NH). All diets contained ～20% grain (dry matter basis). Treatments consisted of 100% corn (0B), 67% corn and 33% hull-less barley (33B), 33% corn and 67% hull-less barley (67B), and 100% hull-less barley (100B) as the grain sources. Total-tract nutrient digestibility was estimated using lanthanum chloride (LaCl₃) as an external marker. Dry matter intake differed quadratically among treatments, being lowest for 67B and highest for 0B and 100B. Feeding hull-less barley did not affect milk yield, and milk fat concentration differed cubically among treatments. The cubic response was attributed to the higher milk fat concentration observed for the diet containing 67B. Neither the concentrations in milk of protein and lactose nor the yields of protein and lactose differed among treatments. The proportion of de novo synthesized fatty acids in milk did not differ among treatments. The apparent total-tract digestibility of dry matter, crude protein, and neutral detergent fiber did not differ among treatments. Although a quadratic effect was observed, starch digestibility was minimally affected by treatments. In conclusion, this study indicates that hull-less barley grain is as good as corn grain as an energy source when formulating diets for high-producing dairy cows.     

PRODUCTION OF α-AMYLASES IN GERMINATING WHOLE AND INCUBATING DE-EMBRYONATED BARLEY KERNELS*

α-Amylases produced in germinated barley and incubated de-embryonated barley kernels (cv. Bonanza), in the absence and presence of gibberellic acid (GA₃), were analyzed qualitatively by polyacrylamide gel isoelectric focusing (PAG-IEF) and quantitatively by chromatofocusing. Identical patterns of α-amylase components were obtained for both germinated barley and incubated de-embryonated barley kernels at each germination/incubation stage, in the absence or presence of GA₃. Total α-amylase increased rapidly in the germinating whole seed whereas in the incubating de-embryonated grain the α-amylase activity increase was much slower. Addition of exogenous GA₃ did not induce production of higher levels of α-amylase in either the germinating whole or incubating de-embryonated barley kernel. Quantitative chromatofocusing analysis revealed that the proportion of α-amylase III to α-amylase II activity decreased linearly with germination time in the whole grain but remained constant in the incubating de-embryonated grain in the absence or presence of GA₃. The major proportion of α-amylase activity in the germinating whole grain and incubating de-embryonated grain was synthesized in the form of α-amylase II components. However, α-amylase I represented a larger proportion of the total α-amylase activity produced in the incubating de-embryonated grain, as compared to the germinating whole seed in the absence or presence of GA₃. These results suggest that embryo excision differentially affects production of α-amylase II as compared to α-amylase I.     

RECOGNITION OF TWO LIPASES FROM BARLEY AND GREEN MALT

Lipase was extracted from ground samples of germinating and ungerminated barley, using the detergent Triton X-100. Enzyme activity, measured by the release of oleic acid from radioactively labelled triolein, was approximately half that in suspensions of barley flour. Two distinct lipases, both active at neutral pHs, and having similar molecular weights (around 400,000) but differing in their ionic properties, were isolated from barley. The more abundant lipase was found mainly in the embryo, while the other was located in the endosperm. Both total and extractable lipase activity increased during germination.