Potential use of visible and near infrared reflectance spectroscopy for the estimation of nitrogen fractions in forages harvested from permanent meadows

One‐hundred and ninety‐two herbage samples from permanent meadows located in the mountains of León (NW Spain) were analyzed for total nitrogen (total N), nitrogen in trichloroacetic acid precipitated matter (TCAN), borate–phosphate buffer insoluble nitrogen (BPBN), neutral‐detergent insoluble nitrogen (NDIN) and acid‐detergent insoluble nitrogen (ADIN). These data were used to calculate the partition of nitrogen fractions proposed by the Cornell Net Carbohydrate and Protein System (CNCPS): A (total N ? TCAN), B₁ (TCAN ? BPBN), B₂ (BPBN ? NDIN), B₃ (NDIN ? ADIN) and C (ADIN). Near‐infrared reflectance spectroscopy (NIRS) technology accurately predicted total N, TCAN and NDIN, as judged by coefficient of determination (R²) and ratio performance deviation (RPD) values greater than 0.90 and 2.5, respectively. The rest of the insoluble N fractions (BPBN and ADIN) were predicted with less accuracy by NIRS. Estimations of CNCPS N fractions (A, B₁, B₂, B₃ and C) using visible–NIR spectra of forage samples did not allow accurate predictions (R² < 0.90; RPD < 2.5). Copyright © 2005 Society of Chemical Industry     

Preliminary characterization of an Italian craft durum wheat beer

In recent years, there has been increasing interest in the production of beers brewed using raw materials of local origin. Many micro‐breweries have been established in Italy, particularly in Sardinia, where some have started to use Sardinian wheat to produce a beer that has a regional connection. The most widespread wheat cultivar used in Italy has been Senatore Cappelli, which is still grown in Sardinia and in some other regions. Bread produced with this type of wheat is characterized by a high protein content and good sensory properties. Owing to its origin, this cultivar is being considered for use in beer production. In this work, a Sardinian durum wheat beer was compared with two other wheat beers brewed in Europe (Germany and the Czech Republic). Standard beer chemical analyses, along with volatile and sensorial profiles, were used to characterize the Sardinian craft durum wheat beer. Copyright © 2014 The Institute of Brewing & Distilling     

Rumen digestion kinetics,microbial yield,and omasal flows of nonmicrobial,bacterial, and protozoal amino acids in lactating dairy cattle fed fermentation by-products or urea as a soluble nitrogen source

The objective of this study was to evaluate the effect of a fermentation by-product on rumen function, microbial yield, and composition and flows of nutrients from the rumen in high-producing lactating dairy cattle. Eight ruminally cannulated multiparous Holstein cows averaging (mean ± standard deviation) 60 ± 10 d in milk and 637 ± 38 kg of body weight were randomly assigned to 1 of 2 treatment sequences in a switchback design. Treatment diets contained (dry matter basis) 44% corn silage, 13% alfalfa silage, 12% ground corn, and 31% protein premix, containing either a control mix of urea and wheat middlings (CON) or a commercial fermentation by-product meal (Fermenten, Arm and Hammer Animal Nutrition, Princeton, NJ) at 3% diet inclusion rate (EXP). The trial consisted of three 28-d experimental periods, where each period consisted of 21 d of diet adaptation and 7 d of data and sample collection. A triple-marker technique and double-labeled ¹⁵N¹⁵N-urea were used to were used to measure protozoal, bacterial, and nonmicrobial omasal flow of AA. Rumen pool sizes and omasal flows were used to determine digestion parameters, including fractional rates of carbohydrate digestion, microbial growth, and yield of microbial biomass per gram of degraded substrate. Fermentation by-product inclusion in EXP diets increased microbial N and amino acid N content in microbes relative to microbes from CON cows fed the urea control. Microbial AA profile did not differ between diets. Daily omasal flows of AA were increased in EXP cows as a result of decreased degradation of feed protein. The inclusion of the fermentation by-product increased nonmicrobial AA flow in cows fed EXP versus CON. Average protozoal contribution to microbial N flow was 16.8%, yet protozoa accounted for 21% of the microbial AA flow, with a range of 8 to 46% for individual AA. Cows in this study maintained an average rumen pool size of 320 g of microbial N, and bacterial and protozoal pools were estimated at 4 different theoretical levels of selective protozoa retention. Fractional growth rate of all microbes was estimated to be 0.069 h^?1, with a yield of 0.44 g of microbial biomass per gram of carbohydrate degraded. Results indicated that fermentation by-product can increase omasal flow of AA while maintaining adequate rumen N available for microbial growth and protein synthesis. Simulations from a developmental version of the Cornell Net Carbohydrate and Protein System indicated strong agreement between predicted and observed values, with some areas key for improvement in AA flow and bacterial versus protozoal N partitioning.     

Effects of a commercial fermentation byproduct or urea on milk production,rumen metabolism,and omasal flow of nutrients in lactating dairy cattle

The objective of this study was to evaluate the effects of a fermentation byproduct on rumen fermentation and microbial yield in high producing lactating dairy cattle. Eight ruminally cannulated multiparous Holstein cows averaging (mean ± standard deviation) 60 ± 10 d in milk and 637 ± 38 kg of body weight were assigned to 1 of 2 treatment sequences in a switchback design. Treatment diets contained (dry matter basis) 44% corn silage, 13% alfalfa silage, 12% ground corn, and 31% premix containing either a control mix of urea and wheat middlings (CON) or a commercial fermentation byproduct meal (Fermenten, Arm and Hammer Animal Nutrition, Princeton, NJ) at 3% diet inclusion rate (EXP). Diets were formulated to be isonitrogenous and isocaloric, with similar levels of neutral detergent fiber and starch. The trial consisted of three 28-d experimental periods, where each period consisted of 21 d of diet adaptation and 7 d of data and sample collection. Omasal nutrient flows were determined using a triple-marker technique and double-labeled ¹⁵N¹⁵N-urea. The EXP diet provided 18 g/d more nonammonia N versus the CON diet, representing 3.0% of total N intake. Energy-corrected milk yield (41.7 and 43.1 kg/d for CON and EXP, respectively), milk fat, and protein yield and content did not differ between treatments. Total dry matter intake was similar between treatments (25.5 and 26.4 kg/d for CON and EXP, respectively). Ammonia N concentration and pool size in the rumen was greater in cows fed the EXP diet. No differences were observed in rumen or total-tract dry matter, organic matter, or neutral detergent fiber digestibility. Ruminal degradation of feed N was 15% lower in cows fed EXP diets, resulting in differences in omasal N flows. Results demonstrated the fermentation byproduct meal had a sparing effect on degradable feed protein, but did not increase microbial N flow from the rumen.     

Identification of durum wheat cultivars and monovarietal semolinas by analysis of DNA microsatellites

 Microsatellites isolated in bread wheat were used to identify 20 Italian durum wheat (Triticum turgidum var. durum L.) cultivars. A total of 15 microsatellite primer pairs were tested against DNA extracted from leaf tissue, single seeds and semolina. Twelve markers showed allelic polymorphism among the 20 cultivars, providing a total of 41 different alleles. Firstly, an analysis of microsatellite informativeness in the chosen set of durum wheat cultivars was made and a set of highly polymorphic microsatellites was established. Secondly, among the most polymorphic cultivars, the minimum number of microsatellites able to distinguish all cultivars was determined. A set of five microsatellites was found sufficient to differentiate the durum wheat cultivars examined. The method is directly applicable to seeds and semolina, and is suitable for detecting seed mixtures in the same seed lot. Received: 22 February 1999 / Revised version: 19 April 1999     

Chemical composition of dehulled seeds of selected lupin cultivars in comparison to pea and soya bean

With the objective of promoting the cultivation, usage, and consumption of lupin, in the present study, the chemical and fibre composition of dehulled seeds of seven cultivars of different lupin species (Lupinus angustifolius, Lupinus albus and Lupinus luteus) was determined in comparison to pea (Pisum sativum) and soya bean (Glycine max).     

Processing and characterization of durum wheat bread enriched with antioxidant from yellow pepper flour

The effect of the addition of yellow pepper flour on bread physico-chemical and sensorial properties was addressed in this study. In particular, vegetable flour concentration was set at 25%; in order to optimize the bread sensorial properties, yellow pepper flour was separately hydrated at three different water content levels. Texture analysis were carried out on both dough and bread samples to evaluate their firmness. Furthermore, tomographic analysis was performed on the same samples in order to provide a more detailed view of their texture. Estimation of the glycemic response, determination of the carotenoids content and sensory analysis of the fortified bread were also determined. Results highlighted that the highest glycemic index was achieved in bread sample having the highest water content and that showed the worst results in terms of texture. Among the studied samples, bread with medium hydration level showed good structural characteristic, double anti-oxidant content compared to the control bread (CTRL S) and the highest sensorial quality.     

Chemical composition and protein quality of newly released groundnut (Arachis hypogaea L ) cultivars

Five groundnut (Aruchis hypogueu L) cultivars developed by the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) and two local cultivars as controls were grown in post-rainy and rainy seasons at Patancheru, India. They were analysed for their proximate composition, minerals and trace elements, amino acid composition, true protein digestibility (TD), biological value (BV), net protein utilisation (NPU), and protein efficiency ratio. One-hundred seed mass, protein content and TD were significantly higher in the post-rainy season while starch, sugars, BV and NPU were significantly higher in the rainy season. Post-rainy cultivars exhibited higher concentrations of potassium, calcium, iron and several essential and non-essential amino acids. TD of blanched groundnut was better than that of the whole seeds. The composition and protein quality of ICRISAT cultivars were comparable to those of the controls.     

Chemical composition,digestibility and protein quality of 12 sunflower (Helianthus annuus L) cultivars

Twelve sunflower (Helianthus annuus L) cultivars grown in Spain were analysed and tested in experiments with rats. The dehulled seeds contained an average of 32.2 MJ kg⁻¹ dry matter (DM) gross energy, 653 g kg⁻¹ DM fat, 60 g kg⁻¹ DM total non-starch polysaccharides (NSP) and 6 g kg⁻¹ DM Klason lignin. The sunflower seed hulls contained 20.2 MJ kg⁻¹ DM gross energy, 53 g kg⁻¹ DM fat, 562 g kg⁻¹ DM total NSPs and 239 g kg⁻¹ DM Klason lignin. The sunflower samples were dehulled and partially defatted (to ∼17% fat) and included in diets for rats. The dehulled, partially defatted samples contained on average 74.6 g nitrogen kg⁻¹ DM and 1.409 mg g⁻¹ phenolic compounds (chlorogenic acid + caffeic acid + derivative 1 + derivative 2) varying from 0.677 to 2.847 mg g⁻¹. Groups of five growing rats were fed diets (9.38% crude protein) containing one of the sunflower cultivars as the only source of protein. Apparent ileal and faecal digestibilities were determined by using an indigestible marker (Cr₂O₃) and faecal digestibility based on total faecal collections. Apparent ileal, caecal and faecal digestibilities of organic matter were 81.2–91.5% (P = 0.05), 95.8–97.1% (P = 0.005) and 94.7–95.3% (P = 0.94) respectively. The apparent faecal digestibilities of DM, energy and protein (N × 6.25) were 93.2–93.8%, 93.5–94.3% and 81.6–84.3% respectively with no differences among cultivars. Biological value (BV) ranged between 63.8 and 73.2% (P = 0.0001) and net protein utilisation (NPU) between 59.9 and 69.5% (P = 0.0001). BV and NPU were positively correlated with lysine and threonine contents, but no correlation with the analysed phenolic compounds was detected. © 1999 Society of Chemical Industry     

Effect of kilning on the composition of protein and arabinoxylan in wheat malt

To explore the effect of kilning on the quality of wheat malt, wheat variety LM21 was malted with three different kilning programmes. Protein composition and arabinoxylan, xylanase (EC 3.2.1.8) activity, diastatic power and free amino nitrogen (FAN) were evaluated. Arabinoxylan content and xylanase activity were monitored during the kilning process. The results showed that the malt obtained from the kilning programme A showed the highest diastatic power, Kolbach index, FAN and lowest wort viscosity. Total arabinoxylan content showed no significant change during the kilning process, while the water extractable arabinoxylan and the xylanase activity reached the maximum values at the kilning temperature of 55°C, after which the xylanase activity decreased with the increase in kilning temperature. Extending kilning time at 40–50°C increased the diastatic power, FAN and Kolbach index and reduced the wort viscosity. © 2019 The Institute of Brewing & Distilling     

Studies on protein and its high‐molecular‐weight subunit composition in relation to chapati‐making quality of Indian wheat cultivars

In order to predict the suitability of wheat for chapati making, 15 Indian wheat cultivars were studied for various protein characteristics in relation to chapati‐making quality. The cultivars varied considerably in their protein characteristics and chapati‐making potential. Results clearly indicated that both quantitative and qualitative characteristics of proteins influenced the chapati‐making potential of cultivars. Puffed height, the important qualitative parameter of chapati, was positively correlated with protein content (r = 0.62, p < 0.05), gluten content (r = 0.79, p < 0.01), sodium dodecyl sulphate (SDS) sedimentation value (r = 0.57, p < 0.05) and Glu‐1 quality scores of high‐molecular‐weight (HMW) subunits (r = 0.66, p < 0.01). Overall quality score of chapati was positively correlated with gluten content (r = 0.64, p < 0.01), SDS sedimentation value (r = 0.60, p < 0.05) and Glu‐1 score (r = 0.58, p < 0.05). HMW subunit composition varied considerably among cultivars. Cultivars having 5 + 10 subunits at the Glu‐1D chromosome, a protein content of about 130 g kg^?1 and SDS sedimentation value around 75 ml yielded excellent chapatis, while those having 2 + 12 subunits, a protein content of about 115 g kg^?1 and SDS sedimentation value around 55 ml resulted in poor chapatis. Interestingly, the presence of the 1BL/1RS chromosome in cultivars had no adverse effect on chapati quality. © 2003 Society of Chemical Industry     

Improved methodology for the characterisation of transgenic Bt-11 maize cultivars using RP-HPLC profiles of albumin,globulin, prolamin,and glutelin protein fractions and chemometric analysis

A clear differentiation between Bt-11 transgenic and isogenic non-transgenic maize cultivars has successfully achieved analysing the perfusion and monolithic RP-HPLC profiles of the albumin, globulin, prolamin, and glutelin maize fractions together with a discriminant analysis. Significant differences between transgenic and isogenic non-transgenic cultivars were observed in the chromatograms obtained from any of the four protein fractions. The application of linear discriminant analysis to the area percentages corresponding to every peak detected in every protein fraction was successfully employed for the classification of transgenic Bt maize lines obtaining a global percentage of correct classification of 100%. For perfusion RP-HPLC, the variables with more discriminant power and prediction capability were the following peaks: peaks 1 and 3 for albumins, peak 2 for globulins, peaks 3 and 6 for prolamins, and peaks 7 and 8 for glutelins. In the case of monolithic RP-HPLC, the variables were peaks 2 and 3 for albumins, peak 5 for globulins, peaks 5, 6, and 7 of prolamins, and peak 10 for glutelins.     

黄酒生麦曲贮存期理化变化

为了在黄酒生产过程中更加合理地使用生麦曲,通过对黄酒生麦曲在贮存期间的糖化力、液化力、总酸和水分等指标的定期测定,找出黄酒生麦曲在贮存过程中理化指标的变化规律。结果表明：生麦曲贮存有一定期限,超过一定期限后,其理化指标有所下降,会影响生麦曲的整体质量。     

超高压对肉及肉制品组织结构和主要化学组成分影响的研究进展

超高压作为一种新型冷杀菌技术,不仅具有杀菌、灭酶、保留产品特色风味和色泽等特点,还可以显著改善肉制品的质构和保油保水性,可以生产适合厌食症患者食用的新型口感的低温凝胶类肉制品,这是通过对蛋白质等肌肉化学组成分的高压修饰实现的.本文对超高压技术的原理进行简单介绍,并综述了超高压对肉及肉制品各组织结构(肌肉组织、结缔组织和脂肪组织)及化学成分(水分及蛋白质)影响的研究进展,旨在为该新技术在肉及肉制品中的应用提供相应理论参考.     

Chemical Composition,Amino Acid Content and Protein Quality of the Little-Known Legume Bauhinia purpurea L

Some nutritional and antinutritional characteristics and biological value of Bauhinia purpurea L seeds were studied. The mature seeds contained (g kg^-1 as is) 271·7 crude protein, 58·7 crude fibre, 124·5 crude fat, 29·3 ash and 515·3 carbohydrates. Potassium, phosphorus and iron occurred in higher concentrations when compared with commonly consumed legumes. The globulins and albumins together constituted major storage proteins (82% total protein). The essential amino acid profile of total seed proteins compared well with the FAO/WHO reference pattern except for a deficiency of sulphur-containing amino acids and tryptophan. When compared with the globulins, the albumins appeared to be a rich source of cystine, methionine, threonine, lysine and tryptophan. Seed lipids contained high levels of the unsaturated fatty acids, oleic and linoleic, which accounted for 62·6% of total fatty acids recovered. Both dry heating and autoclaving significantly reduced the antinutritional compounds. The in vitro protein digestibilities of raw, dry-heated and autoclaved seeds were 59·5, 72·3 and 78·7%, respectively. True digestibility and net protein utilisation were significantly higher in processed seed samples compared with raw seeds. Regarding utilisable protein, autoclaved samples exhibited relatively higher values than raw seeds. © 1997 SCI.