菲律宾蛤仔外套膜液含氮物分布特性及贮藏变化

以活品菲律宾蛤仔外套膜液为研究对象,对外套膜液含氮物以及在活品贮藏过程中的变化进行了分析。鲜活原料分为四个处理组,即对照组、15 ℃室温下的湿藏与干藏组、及4 ℃冷却干藏组。结果显示,外套膜液水分含量高达95%以上;干物质中主要由灰分、蛋白及多糖组成,含量分别为69.41%、15.82%及15.11%;外套膜液抽提氮占总氮70%。与原料组相比,三个贮藏组的总氮、抽提氮、游离氨基酸和总糖有明显升高趋势,总体而言,干藏比湿藏高,冷却干藏比室温干藏高。游离氨基酸分析结果显示,不同贮藏组的各个氨基酸虽存在明显差异,具有呈味功能的谷氨酸、甘氨酸、精氨酸均占总FAA的50%以上;7种必需氨基酸包括苏氨酸、缬氨酸、甲硫氨酸、异亮氨酸、亮氨酸、苯丙氨酸及赖氨酸均有检测,其中赖氨酸含量最高。蛋白态氮的氨基酸组成分析表明,各个贮藏组苏氨酸、缬氨酸、甲硫氨酸、异亮氨酸、亮氨酸、苯丙氨酸及赖氨酸等必需氨基酸含量占总氨基酸的比值在25%~37%。总之,不同的贮藏处置对菲律宾蛤仔含氮物分布均有影响,其中冷却干藏的影响最大。菲律宾蛤仔外套膜液富含蛋白与多糖,其富含呈味FAA及氨基酸的特点,为开发具有营养功能的海鲜调味料提供参考。     

THE POTENTIAL OF TERMINALIA CATAPPA (TROPICAL ALMOND) SEED AS A SOURCE OF DIETARY PROTEIN

The nutritional value of Terminalia catappa seed as a source of dietary protein was investigated. The crude protein content of the seed was high (25.81%). The amino acid analysis showed a good pattern of the essential amino acids (EAA) (in g/16 g N) - leucine (7.32), isoleucine (3.58), valine (2.74), phenylalanine (3.04), tryptophan (0.9), methionine (1.48), lysine (3.39), threonine (2.94), histidine (2.96). Tyrosine (2.12) is the limiting amino acid. The protein quality of the seed was evaluated by in vivo bioassays using weanling male Sprague Dawley rats (50–60 g). The indices of protein quality measured include PER, BV, NPU and TD. There were positive correlation between PER and BV (r = 0.7105), PER and body weight gain (r = 0.9157), PER and nitrogen intake (r = 0.7428). The results showed that T. catappa seed protein has a good pattern of the EAA, is highly digestible, can support growth and positive nitrogen balance and thus has a high dietary protein quality.     

THE AMINO ACIDS CONTENT OF SOME IRAQI DATES

SUMMARY –Amino acid content and nutritive value of three varieties of Iraqi dates was studied. Protein of the date was acid hydrolyzed for 24 hr and the amino acid content determined in a Phoenix automatic analyzer. The protein content on a fresh weight basis was 1.96% for Zahdi, 1.89% for Hillawi and 2.38% for Sayer. The following amino acids were present in these varieties: lysine, histidine, arginine, aspartic acid, threonine, glutamic acid, serine, prolin, glycine, alanine, cystine, valine, methionine, isoleucine, leucine, tyrosine and phenylalanine. Glutamic acid was present in highest concentration and Sayer variety contained more amino acids than Hillawi and Zahdi. Tryptophan and half-cystine may have been destroyed during acid hydrolysis.     

Effects of increased supply of essential amino acids on the metabolism of the isolated perfused guinea-pig mammary gland.

The effects of high rates of infusion of essential amino acids on amino acid uptake by the isolated perfused guinea-pig mammary gland were studied. Infusion of methionine, tyrosine, phenylalanine, histidine and tryptophan (designated group 1) resulted in significant increases in the uptakes of tyrosine, phenylalanine and histidine. Methionine, tryptophan and other essential amino acids were not significantly affected. Infusion of threonine, valine, isoleucine, leucine, lysine and arginine (designated group 2) resulted in significant increases in uptake of all these amino acids. Group 1 amino acid uptake was not significantly affected. Infusion of all the essential amino acids (i.e. groups 1 and 2 together) resulted in significant increases in all their uptakes. Using as index 'the predicted rate of protein synthesis', infusion of group 1 and 2 together led to an apparent 27% increase in protein synthesis. The above results are discussed in relation to the control of milk protein synthesis by limiting essential amino acids.     

Effects of jugular-infused lysine, methionine, and branched-chain amino acids on milk protein synthesis in high-producing dairy cows

In addition to lysine and methionine, current ration-balancing programs suggest that branched-chain amino acid (BCAA) supply may also be limiting in dairy cows. The objective of this study was to investigate whether BCAA, leucine, isoleucine, and valine become limiting for milk protein synthesis when methionine and lysine supply were not limiting. Nine multiparous Holstein cows with an average milk production of 53.5 ± 7.1 kg/d were randomly assigned to 7-d continuous jugular infusions of saline (CTL), methionine and lysine (ML; 12 g and 21 g/d, respectively), or ML plus leucine, isoleucine, and valine (ML+BCAA; 35 g, 15 g, and 15 g/d, respectively) in a 3 × 3 Latin square design with 3 infusion periods separated by 7-d noninfusion periods. The basal diet consisted of 40% corn silage, 14% alfalfa hay, and a concentrate mix, and respectively supplied lysine, methionine, isoleucine, leucine, and valine as 6.1, 1.8, 4.7, 8.9, and 5.3% of metabolizable protein. Dry matter intake (23.9 kg/d), milk yield (52.8 kg/d), fat content (2.55%), fat yield (1.33 kg/d), lactose content (4.77%), lactose yield (2.51 kg/d), and milk protein efficiency (0.38) were similar across treatments. Protein yield and protein content were not significantly different between ML (1.52 kg/d and 2.88%, respectively) and ML+BCAA (1.51 kg/d and 2.83%, respectively), but they were significantly greater than that of CTL (1.39 kg/d and 2.71%). Cows that received ML+BCAA had less milk urea nitrogen content (10.9 mg/dL) compared with milk of CTL cows (12.4 mg/dL) and ML cows (11.8 mg/dL). Whereas high-producing cows responded positively to methionine and lysine supplementation, no apparent benefits of BCAA supplementation in milk protein synthesis were found. Infusion of BCAA may have stimulated synthesis of other body proteins, probably muscle proteins, as evidenced by decreased milk urea nitrogen.     

超高温灭菌处理对再制干酪蛋白质和氨基酸含量的影响

通过测定不同热处理方式再制干酪的蛋白质和氨基酸含量,研究超高温灭菌对再制干酪蛋白质和氨基酸的影响。结果表明,不同热处理对再制干酪中蛋白质的含量没有显著影响(p>0.05)。但是相比于巴氏灭菌,超高温灭菌再制干酪的必需氨基酸含量显著降低了8.4%~9.0%,其中缬氨酸、蛋氨酸、异亮氨酸、亮氨酸和赖氨酸的含量显著降低(p<0.05)。而且超高温灭菌处理加强了氨基酸的脱氨反应,使再制干酪中氨的含量显著增加(p<0.05)。此次试验为再制干酪的工业化生产提供理论参考。     

马关县不同产地草果氨基酸组成与分析

目的 研究马关县不同产地草果中氨基酸含量与组成。方法 采用Biochrom30+型氨基酸分析仪检测5个乡镇产草果中氨基酸。结果 草果M2、M4、M5检出17种氨基酸,7种必需氨基酸;草果M1、M3检出16种氨基酸,未检出蛋氨酸,且不同产地草果的氨基酸具有差异。草果TAA为36.02mg/g～45.79mg/g,EAA为14.71mg/g～16.42mg/g,以谷氨酸(6.67mg/g),天冬氨酸(4.72mg/g)含量较高。氨基酸比值系数法显示草果中蛋氨酸+胱氨酸、赖氨酸均为不足,亮氨酸、苯丙氨酸+酪氨酸、缬氨酸均为过剩,第一限制性氨基酸为蛋氨酸+胱氨酸。草果中呈味类氨基酸和药用氨基酸含量丰富,分别占TAA的89%、64%。SRC比值系数分显示草果M2得分最高,为65.40。结论 不同乡镇产草果中的氨基酸含量有显著差异,综合分析氨基酸营养价值最高的是草果M2。     

Protein and free amino acid patterns in maize ensiled with or without urea

Free and protein amino acid contents of whole-plant maize ensiled with or without urea were determined at intervals during the fermentation process. The free amino acid content of both untreated and urea-treated silage increased with time in storage, but the increases were generally larger in the treated silage. The true protein of untreated silage decreased with time in storage. In urea-treated silage many individual amino acids increased considerably. Among those were the essential amino acids isoleucine, lysine, threonine and valine. The result was a net gain of several amino acids in the treated silage while there was a general decline of most amino acids in the untreated silage. Urea-treated silage at day 20 contained 38% more true protein and 150% more free amino acids than did untreated silage. The implications of these changes for dairy cattle nutrition are discussed.     

Effect of technological processing and preservation method on amino acid content and protein quality in kale (Brassica oleracea L. var. acephala) leaves

BACKGROUND: The aim of the investigation was to evaluate the level of amino acids and quality of protein in raw and processed kale leaves. RESULTS: In all samples the dominant amino acids in g kg^?1 raw matter were glutamic acid, aspartic acid and proline. In raw kale leaves the limiting amino acids were lysine, isoleucine and cystine with methionine, and in the remaining products also valine and leucine. Blanched kale leaves contained 88% of the amino acid content in raw leaves, 76% in cooked leaves, and 69–77% and 71–72% of initial levels in frozen and canned products, respectively. In raw, blanched and cooked leaves essential amino acids comprised 44%, 44% and 47%, respectively, of total amino acids; in frozen and canned leaves the proportions were 46% and 44%, respectively. The essential amino acid index was 97 for canned products, 100–109 for frozen leaves, and 117 for raw kale leaves. CONCLUSION: Raw and processed (blanched or cooked) kale leaves are a good source of amino acids. Copyright © 2011 Society of Chemical Industry     

DIETARY FATTY ACIDS AND AMINO ACIDS OF CAMELINA SATIVA SEED

Abstract Camelina sativa ( L. ) Crantz is an ancient oilseed crop. Camelina seed can be used as a food ingredient and raw material for the production of oil. The by-product from the production of oil by pressing (oil cakes) was traditionally used as fodder ingredient.
Camelina seed samples for analyses were collected from geographically remote localities in Europe and in Scandinavia (6° W - 25° E, 48 - 61° N). The seed was analyzed for the content of oil, fatty acids, total nitrogen and amino acids.
The mean content of oil in the seed was 43.3 ± 0.22%/DM. The predominating acid, α-linolenic (18:3 n-3), was 37.8 ± 0.17%; and others were oleic acid (18:1 n-6) 13.4 ± 0.13%; linoleic acid (18:2 n-6) 14.8 ± 0.12%; gondoic acid (20: 1 n-9) 15.4 ± 0.16% and erucic acid (22: 1 n-9) was 2.76 ± 0.07%/total FA.
Crude protein was 42.5 ± 0.46%/fat free DM. Considerable amounts of essential amino acids were present, such as arginine 8.15 ± 0.06%; glycine 5.44 ± 0.04%; isoleucine 3.96 ± 0.02%; leucine 6.63 ± 0.04%; lysine 4.95 ± 0.04%; phenylalanine 4.19 ± 0.04%; proline 5.09 ± 0.03%; threonine 4.25 ± 0.03% and valine 5.42 ± 0.04%. The methionine content was 1.72 ± 0.04% and cystine, 2.12 ± 0.05% (A.A. g/16 g N).     

烟叶中游离氨基酸与化学成分派生值之间的关系

系统地分析了烤烟烟叶中游离氨基酸与化学成分派生值的关系。参试材料３１份,每个样品鉴定２６项指标。对试验数据分别进行简单相关分析、逐步回归和偏相关分析以及典型相关分析。简单相关分析结果表明,游离氨基酸组分与化学成分派生值之间均存在一定的相关关系。其中丝氨酸、甘氨酸、缬氨酸含量较高,钾／氯比值较高,则烟叶品质较好。逐步回归和偏相关分析系统地分析了游离氨基酸组分对化学成分派生值贡献的大小。其中对施木克值的贡献,以蛋氨酸最大,甘氨酸、丙氨酸和色氨酸次之;对于氧化钾与氯的比值来说,贡献最大的是丝氨酸。典型相关分析结果表明,游离氨基酸与化学成分派生值间的典型相关主要是由组氨酸、酪氨酸、脯氨酸、苯丙氨酸、亮氨酸、丙氨酸、苏氨酸、胱氨酸、天冬氨酸、氨与施木克值、两糖差及糖／碱比值相关显著引起的。     

AVAILABILITY OF AMINO ACIDS IN SARCOPLASMIC FISH PROTEINS COMPLEXED WITH SODIUM HEXAMETAPHOSPHATE

SUMMARY– Comparisons were made on the availability (enzyme digestion) of 4 amino acids (lysine, methionine, tryptophan, and threonine) in sarcoplasmic fish proteins and sarcoplasmic fish proteins complexed with sodium hexametaphosphate. The protein complexes were formed by reacting 1% solutions of sarcoplasmic fish proteins at pH values ranging from 2–4 and at phosphate concentrations ranging from 0.005–0.05 M. Uncomplexed sarcoplasmic protein was obtained by precipitation from 70% isopropanol. The samples were digested with the enzyme pronase and the available amino acids were measured with a bio-assay system. No significant differences in the availability (enzyme digestion) of amino acids were found between complexed and noncomplexed samples. Assays of samples dried at 75°C showed that nearly 100% of the methionine, threonine and tryptophan and 85% of the lysine were available. When the samples were subjected to moist heat (50% moisture, 100°C) for up to 24 hr, availability of lysine, methionine, tryptophan and threonine was reduced by 35, 22, 39 and 34%, respectively. Results of this study indicate that the nutritional characteristics of fish proteins are unimpaired when they are complexed with sodium hexametaphosphate.     

不同注水比例对猪肉营养品质的影响

目的探讨不同注水比例对猪肉的营养流失情况。方法以猪背最长肌为原料,分别注入10%、20%、30%和40%的去离子水,分析了猪肉注水后其流失液的透光率、色差值、灰分含量、蛋白含量、游离氨基酸含量和矿物质含量。结果随着注水比例的增加,猪肉的汁液特性发生显著变化,其中汁液流失率、汁液的透光率、L*值随注水比例增大而逐渐增大,a~*、b~*值随着注水比例的增加而显著降低(P0.05);而且注水会大大降低猪肉的营养价值,随着注水比例的增加,猪肉中蛋白质和矿物质元素的流失量显著增加(P0.05),其中矿物质元素流失量的大小依次为K、P、Na、Mg、Ca、Zn、Cu,同时也造成了17种游离氨基酸的大量流失,包括必需氨基酸苏氨酸、缬氨酸、异亮氨酸、亮氨酸、苯丙氨酸和赖氨酸。结论从猪肉的营养价值而言,为注水猪肉的判别提供理论参考依据。     

喷雾干燥法制备双孢菇蛋白粉工艺优化及其营养价值评价

建立了喷雾干燥法制备双孢菇蛋白粉的工艺。以集粉率为指标,在单因素实验基础上,对进风温度、提取液蛋白质浓度、进料速率进行单因素及正交实验。结果表明:进风温度为165 ℃、提取液蛋白质浓度为40 mg/mL、进料速率为650 mL/h时,集粉率最高为38.8%。所得蛋白粉为奶白色,有鲜蘑菇香味。营养检测分析表明,双孢菇蛋白粉蛋白质含量为65.8%,碳水化合物为8.8%,粗脂肪为0.4%,粗纤维为3.8%,灰分为2.0%,水分为7.20%;氨基酸种类齐全,人体必需的8种氨基酸占氨基酸总量的41.0%;苏氨酸、异亮氨酸、赖氨酸、色氨酸四种必需氨基酸接近FAO/WHO标准。此外,还含有丰富的矿质元素,如重金属镉、铅、砷、汞含量均在国家规定的食品安全标准以内。     

Analysis and metabolite profiling of glucosinolates,anthocyanins and free amino acids in inbred lines of green and red cabbage (Brassica oleracea L.)

We profiled and quantified glucosinolates (GSLs), anthocyanins and free amino acids in thirty-seven inbred lines green and red cabbage. Analysis of these distinct cabbages revealed the presence of 8 GSLs, 13 anthocyanins and 12 free amino acids. GSL contents were varied among the different lines of cabbage. The maximum levels of glucoraphanin (14.91 μmol/g DW) and glucobrassicin (12.37) were found in FX 1-28 and FX 1-32 lines, respectively. Total GSLs in red cabbage lines were 50% higher than those of green cabbage. Anthocyanin contents in red cabbage were ranged from 4.11 to 6.81 mg/g DW in FX 2-3 and FX 1-34 lines, respectively. Among the 13 anthocyanins, both cyanidin 3-(feruloyl) (sinapoyl)diglucoside-5-glucoside and cyanidin 3-(sinapoyl) (sinapoyl)diglucoside-5-glucoside levels were the highest amounts. The amounts of total free amino acids were ranged from 523.5 to 1308 mg/100 g fresh weight (FW) in green cabbage and 484.8 to 1271 in red cabbage, respectively. In red cabbage lines, 9.4% of the total free amino acids accounted essential amino acids such as valine, threonine, isoleucine, leucine and lysine. Thus, the amounts of GSLs, anthocyanins, and amino acids varied widely, and the variations in these compounds between the lines of cabbage were significant.     

Biochemical and nutritional evaluation of Neonotonia wightii (Wight & Arn.) Lackey (Fabaceae)

Seeds of Neonotonia wightii (Wight & Arn.) Lackey (Fabaceae), used as food by Malayali tribals in the Kollihills of Namakkal District, Tamil Nadu in Peninsular India, locally known as Adutheenikai, were analyzed for proximate composition, total (true) seed proteins, amino acid composition, fatty acid composition, minerals and antinutritional factors. The information is reported here for the first time in science. Crude protein, crude fat, ash and nitrogen free extractives constitute 20.6, 12.8, 5.8%, and 52.1g/100g seed flour, respectively. The calorific value of 100-g dry matter of seed material is 1700 kJ. The essential amino acids, leucine, lysine, isoleucine, valine, therionine and histidine are present in higher concentrations as 79, 54, 44, 37, 34 and 32 mg/100g crude protein, respectively. The limiting essential amino acids were cystine, methionine and tryptophan. The unsaturated fatty acids constitute more than 60% of seed lipids. The seeds were found to be a potential source of minerals such as potassium, magnesium, manganese and copper. The concentration of these minerals was relatively more than that of NRC/NAC recommended dietary allowances. The anti-nutritional factors such as total free phenols, tannins, l-DOPA, hydrogen cyanide and phytic acid contents were also determined.     

Redirection of carbon flux to lysine in a recombinant of Corynebacterium lactofermentum ATCC 21799 by limited supply of pantothenate

To increase carbon flux to lysine, minimized production of amino acids that are biosynthetically related to lysine, for example, isoleucine and valine, is required. By limiting the supply of pantothenate, the precursor of coenzyme A, the carbon flux was redirected from isoleucine and valine to lysine in the recombinant of Corynebacterium lactofermentum ATCC 21799 containing the plasmid pGC77. The pGC77 contains hom(dr), thrB, and ilvA encoding feedback-deregulated homoserine dehydrogenase, homoserine kinase, and threonine dehydratase, respectively. At 250 microM of isopropyl-beta-d-thiogalactopyranoside, the recombinant (pGC77) produced lysine, valine, and isoleucine. Limiting the supply of pantothenate from 300 microg/l to 30 microg/l resulted in an increase in lysine (from 4.5 to 6.4 g/l) and decreases in valine (from 3.1 to 1.6 g/l) and isoleucine (from 0.9 to 0.3 g/l) production. The concentration of pyruvate was higher and that of acetate lower in the pantothenate-limited culture than in the control, suggesting that the limited supply of pantothenate delayed the conversion of pyruvate to acetyl-CoA. Increased availability of pyruvate by limiting the supply of pantothenate might favor the integration of pyruvate into the lysine branch. The results of this study are useful for the production of lysine with decreased concentrations of byproducts.     

Amino acid composition of Iraqi dates

Eighteen free and bound amino acids of three commercially packed varieties of Iraqi dates—Hallawi, Khadrawi, and Sayir—were quantitatively determined by means of an automatic amino acid analyser. The following essential amino acids had protein scores lower than 100%: phenylalanine plus tyrosine, isoleucine, lysine, and valine.     

发酵猪肉香肠的营养成分分析与评价

为探讨发酵香肠的营养价值,对发酵猪肉香肠的基本营养成分、氨基酸含量进行了测定,结果表明,发酵猪肉香肠蛋白质含量高达34.3%,显著高于市场上同类产品;脂肪及钠含量较低;氨基酸种类齐全,其中天门冬氨酸、谷氨酸、精氨酸、亮氨酸、赖氨酸等含量较高,必需氨基酸（Essential Amino Acids,EAA）占总氨基酸含量的43%,必需氨基酸与非必需氨基酸（Non-Essential Amino Acids,NEAA）含量之比为0.76,第一、二限制氨基酸分别为缬氨酸、苏氨酸。     

苹果浓缩汁美拉德反应有关影响因素的研究

以苹果制汁新品种鲁加1号和鲁加3号[特拉蒙(Telemon)×富士(Fuji)]的浓缩果汁为试材,研究了苹果浓缩汁贮藏过程中氨基酸、还原糖和5-羟甲基糠醛(5-HMF)含量的变化,并利用几种氨基酸和还原糖分别在柠檬酸-磷酸缓冲液(pH3．20)与苹果浓缩汁中进行美拉德模拟试验。实验结果表明:贮藏过程中,苹果浓缩汁中的赖氨酸、苯丙氨酸、亮氨酸、异亮氨酸、蛋氨酸、苏氨酸的含量呈下降趋势;还原糖含量成波浪式变化,即先上升后下降,然后上升再下降;5-HMF含量先上升后下降;在柠檬酸-磷酸缓冲液中进行美拉德模拟试验其氨基酸与还原糖的反应活性分别与苹果浓缩汁中的反应活性存在较大差异,在两个实验中赖氨酸都具有较大的反应活性。