Protein quality and amino acid-protein relationships of maize,sorghum and rice grain as influenced by nitrogen,phosphorus, potassium and soil moisture stress

In pot and field experiments cereals were grown with greatly differing rates of N, P and K applications. For maize and sorghum, soil moisture levels were also varied. N applications, P- and K-deficiency, and moisture stress generally increased the total N content of grain, from 1.06 to 2.68, 1.01 to 2.42 and 0.81 to 2.33% (as % of DM) for maize, sorghum and rice, respectively. P, K and moisture stress affected the amino acid composition only indirectly through their effects on N concentration. In all three cereals increasing N concentrations were associated with decreases in crude protein of lysine, methionine, cystine, threonine, tryptophan and, generally, with increases of isoleucine, leucine, phenylalanine and glutamate. Lysine as a percentage of dry matter increased up to the highest N concentration in all three cereals. Linear regressions with significant correlation coefficients were found between concentrations of most (g 16 g^?1 N) or all (mg 100 g^?1 DM) amino acids and N content of grain. Based on all experimental data equations for lysine were: g 16 g^?1 N=4.44–0.89 × %N; 4.23–0.86 × % N; 4.39–0.42 × % N for maize, sorghum and rice, respectively. Correction of P- and K-deficiency decreased N content of grain and resulted in higher lysine content and better nutritional value of grain protein, whereas correction of N-deficiency had the opposite effect. The amino acid composition of rice was much more balanced than that of maize and sorghum with a leucine/isoleucine ratio of 2 compared to that of 3 in maize and sorghum. In rat feeding experiments true digestibility of maize and sorghum protein was high (about 95%) but increased only slightly with increasing N in grain, whereas the biological value decreased considerably, from 63 to 55 and from 70 to 58, respectively. The chemical score underestimated the nutritional value of both cereal proteins.     

油菜蜂花粉及其蜂粮的营养成分

本文以油菜蜂花粉及其蜂粮为研究对象,对其常规营养成分、氨基酸和脂肪酸组成进行测定,评价并比较二者的营养价值。结果表明:油菜蜂粮的水分、还原糖和粗脂肪含量显著高于蜂花粉(p<0.05),灰分、蛋白质和总黄酮含量显著低于后者(p<0.05);油菜蜂花粉及其蜂粮中含有8种必需氨基酸,蜂粮总必需氨基酸与总氨基酸的比值(EEA/TAA)显著高于蜂花粉(p<0.05),分别为37.80%和34.74%;油菜蜂花粉和蜂粮的饱和脂肪酸中棕榈酸含量最高,分别为33.81%、33.50%,不饱和脂肪酸中亚麻酸含量最高,分别为32.42%、38.22%,差异显著(p<0.05)。油菜蜂粮是一种优质的必需氨基酸和必需脂肪酸营养源,可以作为一种潜在的原料应用于功能性食品的开发。     

基于GC-IMS分析不同杂粮馒头挥发性成分的差异

为阐明不同杂粮和添加量的馒头挥发性成分差异,本研究采用气相色谱-离子迁移色谱 (Gas Chromatography-Ion Mobility Spectrometry,GC-IMS)分别对质量分数为10%、20%、30%的燕麦、高梁、黍子、藜麦、小米、薏米、荞麦馒头进行挥发性成分测定与分析,根据挥发性成分的指纹图谱并结合多元统计分析方法探究不同杂粮馒头间的差异。结果表明,从杂粮馒头中共鉴定出31种挥发性物质,主要有醛、醇、酯、酮和杂环类化合物,以醛、醇和酯为主。随着杂粮添加量的增加,挥发性成分的种类和浓度有所增加。多元统计分析发现不同杂粮馒头挥发性成分存在一定差异,因此,燕麦和薏米的挥发性物质种类和浓度差异最大,高梁、黍子和藜麦差异次之,小米和荞麦差异最小。GC-IMS联用技术可快速简便检测杂粮馒头中挥发性成分,为杂粮馒头的品质控制和产品开发奠定理论基础,对杂粮深加工具有重要意义。     

预处理对六种黄酒酿造原料酿造特性的研究

为探究不同黄酒酿造原料的酿造特性,以红谷、张杂谷、圆糯米、黍米、金米、粳大米等六种谷物为原料进行浸泡和蒸饭实验,监测浸泡过程中不同原料质构和色泽的动态变化;比较了浸泡后六种米浆水的有机酸和氨基酸组成;并对蒸饭中挥发性风味物质的含量进行分析。结果表明,浸泡过程中六种谷物的颜色和质构参数存在显著差异（P＜0.05）。红谷米浆水的总氨基酸含量最高（976.49 mg/L）,乙酸、酒石酸和柠檬酸含量显著高于其他谷物米浆水的相应含量（P＜0.05）。六种谷物蒸饭样品中共检出165种挥发性成分,其中红谷蒸饭中酸类（11.75 μg/100 g）和酚类含量（10.54 μg/100 g）远高于其他谷物。综上所述,红谷米浆水中氨基酸含量以及蒸米中酸类香气成分较高,这有利于发酵醪的进一步微生物发酵。     

Supplementation of fermented sorghum Kisra bread with legume protein isolates

Kisra is a fermented sorghum flour bread which constitutes the staple diet in Sudan. Sorghum, like other cereals, has some limitations due both to its low protein content and to limitations in some essential amino acids particularly lysine. The objective of the present work was to increase the protein content of Kisra and improve the amino acid profile, especially lysine. Protein isolates were prepared from bonavist bean and white bean by alkaline extraction. The protein isolates were used to increase the protein content of the fermented sorghum dough to about 25%. The legume protein isolate supplemented dough was fermented in the traditional method used for making Kisra. The most significant effect of Kisra supplementation was the improvement in protein content (two-fold) as well as the increase in the limiting amino acids. The results indicated a significant increase (P < 0.01) in lysine in the protein supplemented doughs and Kisras as compared to the control. The increase in lysine ranged 2–2.6 folds. Sorghum supplementation with legume protein isolates was not accompanied by signifi- cant changes in organoleptic properties of the end product.     

Comparative study of phytic acid content,in-vitro protein digestibility and amino acid composition of different types of flat breads

Phytic acid content of eight different types of leavened and unleavened flat breads was determined. It was highest in unleavened and non-fermented whole wheat chapati and lowest in the leavened and fermented white wheat flat bread roghni nan. The effect of baking conditions, bread composition and phytic acid content on in-vitro digestibility of protein was measured using a pepsin multienzyme pH stat technique. The amino acids released were separated by ultrafiltration. The rate of protein digestibility of flat bread and amino acid released depended upon the type of flour used, baking conditions, phytic acid content and other antiproteolytic constituents of breads. Leavening and fermentation of breads resulted in an increase of protein digestibility and availability of amino acids. Addition of soya flour increases the protein digestibility of breads whereas millet flour decreases it.     

Evaluation of the potentials of millet,sorghum and barley with similar nitrogen contents malted at their optimum germination temperatures for use in brewing

Studies on the malting physiology of barley have led to similar studies on millet and sorghum. This study compares the outcomes of the malting physiology of millet, sorghum and barley. Results show that optimal development of diastatic power, soluble nitrogen, hot water extract and the wide range of amino acids of these three cereals is related to optimal malting conditions and appropriate mashing procedures. Transfer of the nitrogen/extract/soluble nitrogen/diastatic concepts of barley malt do not apply to millet and sorghum. However, all the cereals studied produced the range of amino acids required by yeast for fermentation. Sorghum malt released the highest amounts of group 1 amino acids, usually taken up faster by yeast. It also produced and released the highest amounts of amino acids, classified as group 2, which are assimilated more slowly than group 1 amino acids. It also produced and released more of the amino acids that are slowest to be assimilated during fermentation, as well as very high levels of proline. Optic barley malt produced and released the least amount of proline. The fate of proline during yeast fermentation is not clear, but it is believed that proline is not utilized during fermentation. Copyright © 2013 The Institute of Brewing & Distilling     

Extractability,fractionation and nutritional value of low and high tannin sorghum proteins

Kafirins and glutelins were found to be the major, while albumins and globulins were the minor components of sorghum proteins. Marked differences were noticed in both amino acid composition and electrophoretic properties among the sorghum protein fractions. Albumins and globulins were more rich in most of essential amino acids than the other sorghum protein fractions. Dehulling of sorghum grain led to a marked reduction in tannins, and slight reduction in total protein. Low tannin sorghum, Giza 15 variety, had relatively high levels of protein extraction efficiency, albumins, globulins and kafirins, slightly low levels of glutelins and the same amino acids as the high tannin sorghum SX 121 variety.     

秘鲁鱿鱼不同组织营养成分分析与评价

为实现秘鲁鱿鱼资源的高值化利用,分析秘鲁鱿鱼不同组织(头部、肌肉、内脏、眼部和颈部)的基本营养组成、氨基酸组成、脂肪酸组成和矿物质元素含量,比较其不同组织的营养特性。结果表明,秘鲁鱿鱼不同组织之间营养组成存在显著差异。不同组织水分含量均在75%以上,眼部水分含量最高(84.85%);肌肉的粗蛋白含量最高(18.21%)且粗脂肪含量最低(0.33%);内脏的粗脂肪(2.75%)和总糖(0.60%)含量均显著高于其它组织。所有组织均含有18种氨基酸,且不同组织的必需氨基酸含量占比均大于36%。每种必需氨基酸的氨基酸评分(amino acid score,AAS)大多数在0.60以上,化学评分(chemical score,CS)大多数低于鸡蛋蛋白模式。不同组织分别检测出8种~11种脂肪酸,不饱和脂肪酸含量均大于64%,眼部的多不饱和脂肪酸含量最高(76.30%),肌肉组织的二十二碳六烯酸(docosahexaenoic acid,DHA)含量最高(46.83%),颈部的二十碳五烯酸(eicosapentaenoic Acid,EPA)和DHA占比最高(61.49%)。所有组织中常量元素K、Na和P含量最为丰富,内脏中Mg、Ca、Cu、Fe、Zn、Mn、Se的含量远高于其它组织。     

The changes of the yield,composition and nutritive value of leaf protein extracted from vetch and cereal mixtures during three years cultivation

Three mixtures of vetch with cereals (rye, triticale and wheat) were grown during three consecutive seasons 1985/86, 1986/87 and 1987/88 and leaf protein concentrates (LPC) were prepared using the standard method. LPC were analysed for their gross composition and amino acid content. True digestibility (TD) and biological value (BV) of LPC proteins were estimated on rats using the Thomas-Mitchell balance method. There were no statistical differences in green matter and dry matter yield in the course of the whole experiment. However, in the first season (1986) the yield of vetch × rye mixture was apparently higher and that of the other two mixtures was lower than in the next two years. The protein content of LPC in 1986 was lowest, especially in the concentrates obtained from the triticale and wheat mixtures. There were only small differences in amino acid composition of proteins and these differences did not depend on the year of cultivation or species of cereal used. BV of protein extracted from the rye-containing mixtures was always lower than that of other preparations (means of three years: rye 40, triticale 46, wheat 49). Protein extracted in 1987 had the highest BV. It can be concluded that the season of cultivation affects the green and dry matter yield of legume x cereal mixtures though these differences are levelled off during long-term experiments. The LPC quality is affected both by the kind of cereal and year of cultivation.     

盐酸水解方法对鸡肉中氨基酸含量的影响

摘 要: 目的 研究盐酸水解过程中, 水解时间和添加巯基乙醇和苯酚保护剂对鸡肉中18种氨基酸含量的影响, 确定获得鸡肉氨基酸最高含量的盐酸水解方法。方法 以30个鸡胸肌(3种鸡、每种10个)为实验对象, 设计6个水解时间, 研究盐酸水解时间对鸡肉样品中18种氨基酸含量的影响, 确定获得氨基酸最高含量的盐酸水解时间。在上述研究的基础上, 随机选择6个鸡胸肌(3种鸡、每种2个)为实验对象, 设置3个水解时间, 研究巯基乙醇和苯酚对鸡肉样品中18种氨基酸含量的影响, 最终确定获得鸡肉中18种氨基酸最高含量的盐酸水解方法。结果 缬氨酸(valine, Val)和异亮氨酸(isoleucine, Ile)的最佳水解时间为24或26 h, 两水解时间无显著性差异(P>0.05); 其余16种氨基酸的最高含量均在22 h; Ile的含量在盐酸水解法水解24 h显著高于20 和22 h(P<0.05), 但在苯酚+盐酸水解法水解22h含量最高; 天冬氨酸(aspartate, Asp) 的含量在巯基乙醇+盐酸水解法水解22 h显著高于20 和24 h(P<0.05), 但在盐酸水解法水解22h含量最高; 甘氨酸(glycine, Gly)、丙氨酸 (alanine Ala)、酪氨酸(tyrosine, Tyr) 和苯丙氨酸 (phenylalanine, Phe)的含量在苯酚+盐酸水解法水解22 h显著高于20 h(P<0.05), 但水解22与24 h之间无显著性差异(P>0.05), 其中, Gly在苯酚+盐酸水解法水解22 h含量最高, Ala在盐酸水解法水解22 h含量最高, Tyr和Phe在巯基乙醇+盐酸水解法水解22 h含量最高; Val在盐酸水解法水解24 h含量最高, 脯氨酸(proline, Pro)和赖氨酸 (lysine, Lys)在苯酚+盐酸水解法水解22 h含量最高, 亮氨酸 (leucine, Leu) 在巯基乙醇+盐酸水解法水解22 h含量最高; 其余氨基酸在不同水解方法及水解时间中均无显著性差异(P>0.05), 但都在盐酸水解法水解22 h时含量最高。结论 巯基乙醇和苯酚对鸡肉中的含硫氨基酸无保护作用, 获得鸡肉中18种氨基酸最高含量的盐酸水解方法是盐酸水解法水解22 h。     

含不同粗粮粉面包的营养、质构特性、风味化合物

以小麦粉为主要原料,分别添加一定量马铃薯全粉、荞麦粉、薏苡粉、燕麦粉制作粗粮面包,以氨基酸组成、质构、色泽、风味为评价指标,分析粗粮面包营养特性(主要是游离氨基酸含量)、质构特性、色泽变化和挥发性风味化合物的特征,同时以普通面粉面包为对照。结果表明:从质构特性来看,粗粮粉添加量不应超过12%;除薏苡组外,其余组的氨基酸综合评分均高于对照组;粗粮组面包风味较对照组浓郁,风味物质的总量和种类均高于对照组;添加粗粮粉制作的面包会产生一些特别的风味物质,如壬醇、3-甲基十五烷、十八烷、植烷、3-甲基丁酸、2,6-二甲基吡嗪等。因此,添加适量的粗粮粉既能丰富面包的营养,又能产生浓郁的风味物质,而对面包色泽影响不大。     

The production of the Chinese baijiu from sorghum and other cereals

Baijiu is a widely consumed spirit usually distilled from fermented sorghum. Here the use of other cereal grains (wheat, corn, rice and barley) is compared with sorghum. The concentration of ethyl acetate in spirit made from sorghum was found to be higher than in the spirits made using other grains, whereas the concentrations of aldehydes and higher alcohols were lower. Based on sensory evaluations, the flavours were more satisfactory when sorghum was used for making Baijiu. Of the other cereals, the flavour from wheat was better than those of corn, rice and barley for making Baijiu. The ester concentration of the spirit made from the rice was low, whereas aldehyde and alcohol contents were high. An abnormal flavour was found in spirits made from corn or barley. Further work with sorghum showed variations in tannin content, and a correlation between the tannin content and brewing performance. When the content of tannin was <1.94%, the ethyl acetate and ethyl octanoate content were positively correlated with tannin content. In contrast, the ethyl lactate and higher fatty acid ethyl esters content were negatively correlated with tannin content. The results of flavour analysis and sensory evaluation indicated that the ideal sorghum tannin content for producing Baijiu was between 1.0 and 2.0%. Copyright © 2017 The Institute of Brewing & Distilling     

Effects of barley flour and barley protein isolate on chemical, functional, nutritional and biological properties of Pita bread

This study was carried out to investigate the effects of fortification of wheat flour with barley flour (BF) and barley protein isolate (BPI) at three levels; 5, 10 and 15% levels on the chemical composition, nutritional evaluation and biological properties of pita bread. Proteins fractions such as globulin, prolamin, glutelin-1 and glutelin-2 as well as protein isolates were extracted from barley flour and evaluated for protein yield, chemical composition and nutritional quality. Highest yield and essential amino acids contents were obtained in barley protein isolate. SDS-PAGE gels electrophoresis indicated that fortified wheat flour with BPI and BF consists of proteins coming from wheat flour and barley proteins. The contents of essential limiting amino acids in bread were increased from 1.38 to 3.10 g/100 g for lysine and from 0.86 to 1.73 g/100 g for methionine as the ratio of fortification with BF and BPI increased from 0 to 15%. The highest content of total phenolics, antioxidant activity, and inhibitory activity for both angiotensin converting enzyme (ACE) and α-amylase were found in fortified bread with BPI at 15%. Results indicated that bread made from fortification of wheat flour with BF and BPI at 15% showed superior chemical, physico-chemical, nutritional and biological properties.     

粳糯高粱籽粒理化性质及酿酒特性分析

以6种高粱为材料,对高粱籽粒理化性质、出酒率和酒品质等进行测定,分析不同类型高粱品种酿酒特性。结果显示,糯性高粱籽粒吸水率和膨胀率均大于粳性,其中冀酿2号支链淀粉含量最高,为69.84%。粳性辽杂19容重、含水量、蛋白质含量最大,分别为787 g/L、9.66%、8.91%。粳性高粱淀粉颗粒表面光滑,结构较为松散,糯性淀粉浆起始温度、终止温度和热焓值均高于粳性。粳性辽杂19酒中乳酸乙酯含量最高,为227.98 mg/100 mL,其余酯类糯性的均小于粳性。粳性佳县高粱总淀粉、单宁、酒中乙酸乙酯的含量和出酒率均为最高,分别为77.42%、1.22%、229.29 mg/100 mL和41.61%。该研究揭示了粳糯高粱之间籽粒、淀粉理化性质和蒸煮特性存在较大差异,最终导致不同高粱酒香味物质含量不同,结合出酒率得出佳县高粱较适合于陕西省西凤酒的酿造。     

阿克陶引种栽培的5个果桑品种桑葚氨基酸分析与评价

对新疆阿克陶县玉麦乡引种栽植的5个果桑品种的成熟桑葚的氨基酸含量进行了检测,分析了不同品种间的氨基酸组成、总氨基酸、必需氨基酸、鲜味氨基酸、药用氨基酸及支链氨基酸含量的差异,采用RAA、RC、SRC等氨基酸评价指标进行了营养评价。结果表明:5个果桑品种的成熟桑葚中均含有16种氨基酸,总含量为0.802~1.323 g/100 g,其中谷氨酸含量最高,色氨酸和蛋氨酸含量最低,不同品种之间EAA/TAA差异不显著(P>0.05);8632的总氨基酸、必需氨基酸、鲜味氨基酸、药用氨基酸和支链氨基酸的含量均显著高于其它品种,红果2号次之;与FAO/WHO氨基酸模式谱比较得出,除蛋氨酸+胱氨酸之外,其它必需氨基酸接近或符合FAO/WHO氨基酸模式要求;氨基酸比值系数法评定可知第一限制氨基酸为蛋氨酸+胱氨酸,不同品种的SRC评分依次为红果2号>8632>台果>大10>果选2号,红果2号和8632的SRC分别为84.863和82.859。说明5个果桑品种中8632和红果2号的氨基酸营养价值高,作为新疆地区推广的果桑品种具有明显的优势。     

三种酿酒高粱的理化特性与基酒风味分析

以东北粳高粱、自贡小高粱和泸州糯高粱3种高粱为实验对象,模拟浓香型白酒酿造过程,并对所产基酒的风味物质进行了对比分析。结果表明,泸州糯高粱的支链淀粉、粗脂肪、粗蛋白含量最高,分别为53.01%、3.96%、7.94%;东北粳高粱的总淀粉和直链淀粉含量最高,分别为71.35%、28.52%;自贡小高粱的粗脂肪和总淀粉的含量最低,分别为2.49%、61.50%,其他指标趋于其他两者之间;泸州糯高粱的9种氨基酸含量显著高于东北粳高粱和自贡小高粱;对基酒的主要风味物质进行气质联用（GC-MS）分析可知,泸州糯高粱基酒一共检出8种醇类,18种酯类;自贡小高粱基酒一共检出8种醇类,14种酯类;东北粳高粱基酒一共检出6种醇类,13种酯类。     

Release of free ferulic acid and changes in antioxidant properties during the wheat and rye bread making process

Changes in the free ferulic acid (FFA) contents and antioxidant properties during bread making processes were determined. Experimental breads were produced from whole meal and white wheat and rye flours, and fermented using either baker’s yeast or sourdough starter. Sourdough fermented bread contained the highest content of FFA. Release of occurred mainly during dough fermentation. A further increase in the ferulic acid content in the bread crumb and a decrease in the crust was observed. Total antioxidant properties of sourdough bread, defined as the sum of lipophilic and hydrophilic compound activities, were significantly (p<0.05) higher than for yeast bread. Sourdough bread contained more methanol soluble phenolic compounds, proteins, tocochromanols, and oxidized products of fatty acids than yeast bread. The equilibrium between the anti- and pro-oxidative compound contents resulted in similar antioxidant properties for bread using both types of fermentation, and to results observed for the flour used for baking.     

Improving the quality of sorghum injera by decortication and compositing with tef

Injera is an Ethiopian fermented pancake‐like bread made from cereals, with tef being preferred. Decortication and compositing with tef were evaluated as methods to improve the injera‐making quality of red tannin‐free and tannin‐containing sorghums. Both decortication and compositing improved sorghum injera quality. Concerning decortication, mechanical abrasion was found to be more effective than hand pounding because acceptable injera was obtained with lower milling loss. Good quality injera was produced at an extraction rate of 540 g kg^?1 for tannin‐containing and 830 g kg^?1 for tannin‐free sorghum. With compositing, good quality injera was produced with a 50:50 (w/w) composite of whole tannin‐containing sorghum and tef. Both processes reduced the tannin content of the flours, which appeared to relieve the inhibiting effects of tannins on the fermentation. Decortication also seemed to improve sorghum flour injera‐making quality by improving flour pasting as a result of reducing the level of interfering substances such as lipids and proteins. In contrast, the improvement brought about by compositing with tef seemed to be due to inherent differences between tef and sorghum starch granules and an increase in the water solubility index of the flour. Compositing seems to be a more useful method of improving sorghum injera quality than decorticating as it avoids the grain loss associated with decortication. Copyright © 2005 Society of Chemical Industry     

Effect of amino acids on Maillard reaction product formation and total antioxidant capacity in white pan bread

Maillard reaction products (MRPs) can be an important dietary antioxidant source. Bread is the most popular bakery product; however, limited information is available on the antioxidant activities of MRPs generated during bread-baking. This paper reports the effect of different amino acids on bread properties, melanoidin formation and antioxidant activities. Totally six amino acids at four different levels were evaluated. Increasing the amount of amino acid led to darker bread crust, higher melanoidin content and stronger antioxidant activity. Among the six amino acids, bread with glycine had the highest melanoidin content and ABTS radical scavenging activity up to 1079.77 ± 8.43 μmol TE mg⁻¹. Bread with lysine had the highest DPPH radical scavenging activity up to 281.97 ± 10.52 μmol TE mg⁻¹. Bread with alanine had the highest crust metal chelating activity compared with others. Adding certain dietary amino acids is a potential approach to enhance the antioxidant capacity of bread products.