Effects of distillers dried grains with solubles and mineral sources on gaseous emissions

Distillers dried grains with solubles (DDGS), an important ethanol industry co-product, has been used as a high-protein feed in poultry production. Limited studies exist on their effect on air emissions, however. In the current study, 4 diets (2 × 2 factorial design: 0 or 20% DDGS + inorganic or organic mineral sources) were fed to Hy-line W36 hens from 50 to 53 wk of age and the effects of DDGS level and mineral sources on air emissions were monitored continuously for a 23-d period in environmentally controlled chambers. The NH₃, H₂ S, CH₄, nonmethane hydrocarbons, N₂ O, CO₂, and CO₂-equivalent emissions ranged from 0.51 to 0.64 g/day-hen, 0.71 to 0.84 mg/day-hen, 33.9 to 46.0 mg/day-hen, 54.1 to 60.0 mg/day-hen, 66.0 g to 72.2 g/day-hen, and 83.1 to 92.1 g/day-hen, respectively. Feeding DDGS to laying hens resulted in 14% decreased NH₃ emissions but a 19% increase in CH₄ emissions without affecting other gaseous emissions. More than 30% of N, 80% of P, 80% of K, and 50% of Ca was retained in the manure. In conclusion, feeding laying hens a diet containing 20% DDGS may be beneficial for the environment. Substitution for organic trace minerals did not affect hen performance or air emissions.     

彼子和榧实原植物的本草考证——兼与陈重明先生等商榷

中国唐代以来的多数本草著作,均认定《神农本草经》中的彼子和《名医别录》中的榧实,与《唐本草》中的榧子为同物。现代中药学论著考订其原植物为今红豆杉科榧树（榧子）Torreya grandis Fort.ex Lindl.。殊误。经全面考证后确认,彼子是今三尖杉科三尖杉属Cephalotaxus Sieb.et Zucc.植物,榧实是红豆杉科红豆杉属Taxus L.植物,后世本草中的榧子与它们并非同物。     

宁南山区苜蓿地土壤水分和养分变异规律研究

以宁南半干旱黄土丘陵区3年生、7年生、11年生、19年生,以及7年生上坡、中坡、下坡苜蓿地为研究对象,分析了苜蓿地0—5m土壤干层及土壤养分的消长规律。研究结果表明:(1)坡位与种植年限均对土壤水分产生影响,上坡苜蓿地0—5m土壤平均含水量为6.34%,显著小于中坡和下坡;不同旱作年限苜蓿地0—5m土壤含水量排序为:3年生>7年生>19年生>11年生;土壤干燥化指数SDI排序为:上坡>中坡>下坡;3年生>7年生>19年生>11年生,土壤干燥化程度随着土层深度的增加而减弱。待苜蓿老化后土壤水分可以得到恢复,土壤干燥化程度降低,但这一过程需要较长的时间。(2)在土壤旱化过程中,随着坡位的下降,苜蓿地0—100cm层土壤平均有机质、全氮、速效氮、全磷、速效磷、速效钾含量增加;随着土层深度的增加,土壤有机质、全氮、速效氮、全磷、速效磷下降。随着苜蓿旱作时间的延长,土壤有机质、全氮、速效氮、速效磷、全磷、速效磷含量呈下降的趋势;待苜蓿老化严重时,土壤有机质、全氮开始逐渐积累,但仍然处于低水平状态。     

牧区奶干渣组合式发酵剂响应面法优化

以脱脂牦牛乳为试验材料,发酵3.5 h滴定酸度为试验指标,在不同菌种最佳组合方式筛选的研究基础上,利用响应面Box-Behnken中心组合试验研究了4株筛自牧区、发酵性能优良的菌种:保加利亚乳杆菌(MGD1-3)、嗜热链球菌(MGB39-5)、嗜热链球菌(G81-1)、植物乳杆菌(BM5152)不同接种比例对牧区奶干渣发酵效果的影响。结果表明,优化得到最优组合式发酵剂为:MGD1-3体积分数3.06%、MGB39-5体积分数0.64%、G81-1体积分数0.55%、BM5152体积分数2.04%,滴定酸度为75.87°T。为了便于实际操作,确定最终体积接种比为:MGD1-3∶MGB39-5∶G81-1∶BM5152=30∶6∶5∶20,接种量体积分数为6.0%,该条件下进行3次平行试验,得到滴定酸度平均值为74.21°T;将接种优化后组合式发酵剂制成的奶干渣(试验组)与牧区采集奶干渣(对照组)进行感官与理化指标比较,结果表明该组合式发酵剂发酵性能优良。     

辐照杀菌对红枣品质的影响

研究了γ射线辐照红枣的杀菌效果及其对主要有机营养成分、矿物质、维生素、氨基酸含量及感官品质的影响。试验结果表明:红枣辐照杀菌效果显著,经3×103Gy辐照处理后,5个红枣样品的微生物数量均达到国家标准;辐照对红枣中总糖、蛋白质、矿物质及VA、VE、VB1、VB2含量和感官品质无显著影响;辐照后红枣中粗脂肪含量和氨基酸总量比辐照前有所增加,但不显著(P>0.05);VC含量随辐照剂量的增加显著下降(P<0.01),当辐照剂量为3×103Gy时,其含量比对照降低了20.5%;辐照对红枣的感官品质不仅无不良影响,而且在一定程度上还有改善作用。提出了红枣辐照杀菌的适宜剂量为3×103Gy。     

Amino acid digestibility of heat damaged distillers dried grains with solubles fed to pigs

The primary objective of this experiment was to determine the effects of heat treatment on the standardized ileal digestibility(SID) of amino acids(AA) in corn distillers dried grains with solubles(DDGS) fed to growing pigs. The second objective was to develop regression equations that may be used to predict the concentration of SID AA in corn DDGS. A source of corn DDGS was divided into 4 batches that were either not autoclaved or autoclaved at130°C for 10, 20, or 30 min. Four diets containing DDGS from each of the 4 batches were formulated with DDGS being the only source of AA and CP in the diets. A N-free diet also was formulated and used to determine the basal endogenous losses of CP and AA. Ten growing pigs(initial BW: 53.5 ± 3.9 kg) were surgically equipped with a T-cannula in the distal ileum and allotted to a replicated 5 × 4 Youden square design with 5 diets and 4 periods in each square. The SID of CP decreased linearly(P 0.05) from 77.9% in non-autoclaved DDGS to 72.1, 66.1, and 68.5% in the DDGS samples that were autoclaved for 10, 20, or 30 min, respectively. The SID of lysine was quadratically reduced(P 0.05) from 66.8% in the non-autoclaved DDGS to 54.9, 55.3, and 51.9% in the DDGS autoclaved for 10, 20, or30 min, respectively. The concentrations of SID Arginine, Histidine, Leucine, Lysine, Methionine, Phenylalanine, or Threonine may be best predicted by equations that include the concentration of acid detergent insoluble N in the model(r2= 0.76, 0.68, 0.67, 0.84, 0.76, 0.73, or 0.54, respectively). The concentrations of SID Isoleucine and Valine were predicted(r2= 0.58 and 0.54, respectively) by the Lysine:CP ratio, whereas the concentration of SID Tryptophan was predicted(r2= 0.70) by the analyzed concentration of Tryptophan in DDGS. In conclusion, the SID of AA is decreased as a result of heat damage and the concentration of SID AA in heat-damaged DDGS may be predicted by regression equations developed in this experiment.     

香肠自然风干过程中微生物和部分理化性质变化的研究

对如皋香肠在风干期间定时取样,分别测定其pH值,Aw值,亚硝酸钠含量,氯化钠含量,微生物细菌总数及菌群变化。结果显示,香肠的颜色指标发生了较明显变化,切面的颜色随成熟时间的延长变暗;香肠pH值呈现下降趋势;细菌总数和乳酸菌数在风干前8d时不断增加,随后逐渐稳定;氯化钠含量在风干8d前有升高趋势,随后趋向稳定;亚硝酸钠在风干8d前有升高趋势,随后趋向稳定。     

Pond production of Pacific white shrimp,Litopenaeus vannamei,fed grain distillers dried yeast

The objective of this study was to demonstrate the feasibility of four diets formulated to contain increasing levels (0, 50, 100 and 150 g kg^?1 of diet) of grain distillers dried yeast (GDDY) in production diets for Litopenaeus vannamei, reared in outdoor tanks or production ponds. The production pond trial was carried out in 16, 0.1‐ha ponds using four replicates per diet. Juvenile shrimp (38.1 ± 4.26 mg, initial weight) were stocked at 30 shrimp m^?2 for a 16‐week period. The same four diets and a commercial reference diet were offered to shrimp maintained in outdoor tanks over a 12‐week period. A total of 20 tanks were stocked with juvenile shrimp (3.05 ± 0.22 g, initial weight) obtained from production ponds at a density of 30 shrimp per tank (40 shrimp m^?2). At the conclusion of these trials, mean final weight ranged from 19.77 to 23.05 g, yield ranged between 4760 and 5606 kg ha^?1, survival ranged from 69.6% to 89.4%, and feed conversion ratio (FCR) was between 1.02 and 1.23. Shrimp reared in the outdoor tanks confirmed the results of the pond trial. Mean final weight ranged between 18.12 and 18.97 g, survival ranged from 93.3% to 98.3%, and FCR was between 1.25 and 1.29. In both trials, there were no significant differences regarding mean final weight, FCR and survival among dietary treatments. Based on this study, GDDY up to 150 g kg^?1 of diet can be used in L. vannamei commercial feed formulation.     

低盐乳酸菌法与传统法腌干鱼制品的风味比较

为了研究不同腌制方法对鱼肉风味的影响,为腌干鱼制品加工新技术的进一步优化和应用提供理论依据,采用固相微萃取-气相色谱-质谱(SPME-GC-MS)联用法分析,鉴定比较了鲜红牙原料采用低盐乳酸菌法和传统法腌干鱼制品的风味成分变化。结果表明:鲜红牙、低盐乳酸菌法腌干鱼和传统腌干鱼肉中分别检测出80、110、91种挥发性成分,醛、醇、酮类化合物是构成腌干鱼肉独特风味的主要成分。经低盐乳酸菌法腌干的鱼肉挥发性物质对风味贡献较大的醛、醇、酮类化合物总量达35种,而鲜鱼和传统腌干鱼肉中分别只有17和21种。低盐乳酸菌法腌干鱼肉风味物质中含有大量的醇、醛类物质,但不含有胺类物质,在保持传统腌制鱼肉风味的基础上增加了特有的花香味、水果香味及酒香味,提升了鱼肉感官品质。所以采用低盐结合复合乳酸菌法制备腌干鱼,不仅能缩短腌制时间,还能提升腌干鱼肉特有的风味,而且防止了胺类物质的产生,显著提高产品的品质和安全性。     

True Metabolizable Energy and Amino Acid Digestibility of Distillers Dried Grains with Solubles

In recent years, policies encouraging the production of ethanol have stimulated an enormous increase in the production of distillers dried grains with solubles (DDGS). The form of the ingredient that is becoming increasingly available differs from that of previous decades in that it is derived almost entirely from corn and is dried under less severe conditions. Seventeen DDGS samples were obtained from 6 different plants in the midwestern United States from 2002 to 2004. Each sample was analyzed for TME_n, and 8 representative samples were analyzed for total and digestible amino acids (AA) by the precision-fed rooster assay using conventional or cecectomized Single Comb White Leghorn roosters, respectively. Color [lightness (L*), redness (a*), and yellowness (b*)] of each DDGS sample was measured with a Minolta Chroma Meter CR-300. The TME_n ranged from 2,490 to 3,190 kcal/kg (86% DM basis) and had a mean of 2,820 kcal/kg. Variation was noted among samples, presumably reflecting differences in the original corn composition, fermentation, and disposition of solubles. Considerable differences were observed among the true AA digestibilities of the DDGS samples. Most samples were golden in color, and true AA digestibility values were relatively consistent among these samples. The average total concentration and digestibility coefficients of several most limiting AA for the 8 DDGS samples were as follows: Lys, 0.71% (70); Met, 0.54% (87); cystine, 0.56% (74); Thr, 0.96% (75), Val, 1.33% (80), Ile, 0.97% (83); and Arg, 1.09% (84). Correlations were found among digestible Lys, Thr, Arg, His, and Trp and the yellowness (b*) and lightness (L*) of the DDGS samples. In general, DDGS samples that were more yellow and lighter in color had higher total and digestible AA levels. The variation in TME_n and AA digestibility observed among samples strongly indicated that confirmatory analyses should be conducted prior to using samples from a new supplier.