FACTORS CONTROLLING THE FERMENTABLE EXTRACT IN DISTILLERS MALT

The relationships between the alcohol yield obtainable from different malts and some readily measurable parameters have been investigated. Gel filtration studies clearly show that melanoidin-type condensation products, which were previously suggested as a cause of low fermentability, are not produced in significant amounts in highly modified malts. These studies also show important details relating to the hydrolysis of dextrins in distillers' worts and washes. Measurement of the limit dextrinase activity of a range of distillers' malts has indicated that this enzyme is not a limiting factor in determining wort fermentability and its concentration does not correlate with the overall spirit yield. There may be a relationship between the whole amylase complex, as expressed by the diastatic power and wort fermentability. From a study of the reducing sugar contents of worts, it was confirmed that the major factor controlling fermentable extract in malt is the relative amounts of starch-derived sugars in the wort. It now appears possible to determine the fermentability of distilling wort by the standard extract and the reducing power of the wort obtained by the standard I.O.B. extraction.     

废新闻纸碎浆后产生的溶解及胶体物质的分析

对废新闻纸碎浆过程中产生的溶解及胶体物质（DCS）进行了定性与定量分析，研究结果发现溶解物质（DS）的含量占整个DCS含量的90％左右，而胶体物质（CS）的含量仅占10％左右。另外，DCS中碳水化合物的含量明显高于亲脂性抽出物与合成聚合物，而合成聚合物的含量相对比较低。碎浆过程中释放出最多的糖类是木聚糖，仅有少量的聚半孔糖醛酸释放到体系中。在总的脂肪酸与树脂酸（RFA）中脱氢枞酸含量占整个RFA含量的一半以上，另外一种含量比较高的便是枞酸．     

Effects of sucrose supplementation on dry matter intake,milk yield,and blood metabolites of periparturient Holstein dairy cows

Thirty-four multiparous Holstein dairy cows (780 +/- 17.2 kg body weight; 3.4 +/- 0.08 body condition score) were used in a completely randomized design to evaluate the effects of fermentable carbohydrate source on dry matter (DM) intake, milk production, and blood metabolites of transition cows. Treatments were initiated 30 d before expected calving date. After calving, all cows went onto a similar lactating cow diet. Dry matter intake was measured daily, and milk production and composition were measured weekly for 56 d after calving The control diet consisted of 11.5% ground corn, whereas the treatment diet consisted of sucrose replacing 2.7% of ground corn on a DM basis. Prepartum plasma glucose concentrations were higher (66.3 vs. 69.3 +/- 1.13 mg/dl) for cows fed the diet containing sucrose. Glucose concentrations were not different postpartum. Prepartum and postpartum nonesterified fatty acids, blood urea N, and insulin did not differ between treatments. Substitution of sucrose as a readily available carbohydrate source for ground corn did not affect prepartum or postpartum DM intake. Milk yield, 3.5% fat-corrected milk yield, and milk components did not differ between treatments. Results from this research demonstrated that partially replacing ground corn with sucrose did not enhance prepartum or postpartum intake or performance.     

电场和提取剂对提取胞外聚合物的影响

本文研究了电场和提取剂对胞外聚合物提取效果的影响,实验测定了在交流电场下不同的提取剂如：NaOH、EDTA、Tris和硫酸对提取液中的多糖含量,结果表明,电场和提取剂对提取效果有明显影响。     

Alfalfa baleage with increased concentration of nonstructural carbohydrates supplemented with a corn-based concentrate did not improve production and nitrogen utilization in early lactation dairy cows

The objective of this study was to investigate the effects of feeding alfalfa baleage with different concentrations of nonstructural carbohydrates (NSC) supplemented with a common corn-based concentrate on performance, ruminal fermentation profile, N utilization, and omasal flow of nutrients in dairy cows during early lactation. Ten multiparous (8 ruminally cannulated) and 8 primiparous Holstein cows were randomly assigned to treatments (high- or low-NSC diet) in a crossover design. The difference in NSC concentration between the 2 alfalfa baleages fed from d 14 to 21 averaged 14 g of NSC/kg of dry matter (DM). Forages and concentrate were offered in separate meals with forages fed once and concentrate offered 3 times daily. Except for the molar proportion of valerate, which was lowest in cows fed the high-NSC diet, no other changes in ruminal fermentation were observed. Omasal flows of most nitrogenous fractions, including bacterial nonammonia N and AA, were not affected by treatments. Apparent ruminal digestibilities of neutral and acid detergent fiber and N were lowest, whereas that of total ethanol-soluble carbohydrates was highest when feeding the high-NSC diet. Postruminal digestibilities of DM, organic matter, fiber, and N were highest in cows fed the high-NSC diet, resulting in no difference in total-tract digestibilities. Total-tract digestibility of total ethanol-soluble carbohydrates was highest in cows fed the high-NSC diet, but that of starch did not differ across treatments. Although milk yield and total DM intake did not differ between treatments, yields of milk fat and 4% fat-corrected milk decreased significantly in cows fed the high-NSC diet. Milk concentration of urea N was lowest, and that of ruminal NH₃-N highest, in cows fed the high-NSC diet. Plasma urea N concentration tended to be decreased in cows fed the high-NSC diet, but concentrations of AA were not affected by treatments, with the exception of Asp and Cys, both of which were lowest in cows fed the low-NSC diet. Feeding diets with contrasting NSC concentrations did not improve milk production, N utilization, or bacterial protein synthesis, possibly because intakes of NSC and DM were similar between treatments. Overall, results from the current study should be interpreted cautiously because of the lack of difference in dietary NSC intake between treatments and reduced N and fiber intakes when feeding the high-NSC diet.     

Effects of Different Short-Term UV-B Radiation Intensities on Metabolic Characteristics of Porphyra haitanensis

The effects of ultraviolet (UV) radiation, particularly UV-B on algae, have become an important issue as human-caused depletion of the protecting ozone layer has been reported. In this study, the effects of different short-term UV-B radiation on the growth, physiology, and metabolism of Porphyra haitanensis were examined. The growth of P. haitanensis decreased, and the bleaching phenomenon occurred in the thalli. The contents of total amino acids, soluble sugar, total protein, and mycosporine-like amino acids (MAAs) increased under different UV-B radiation intensities. The metabolic profiles of P. haitanensis differed between the control and UV-B radiation-treated groups. Most of the differential metabolites in P. haitanensis were significantly upregulated under UV-B exposure. Short-term enhanced UV-B irradiation significantly affected amino acid metabolism, carbohydrate metabolism, glutathione metabolism, and phenylpropane biosynthesis. The contents of phenylalanine, tyrosine, threonine, and serine were increased, suggesting that amino acid metabolism can promote the synthesis of UV-absorbing substances (such as phenols and MAAs) by providing precursor substances. The contents of sucrose, D-glucose-6-phosphate, and beta-D-fructose-6-phosphate were increased, suggesting that carbohydrate metabolism contributes to maintain energy supply for metabolic activity in response to UV-B exposure. Meanwhile, dehydroascorbic acid (DHA) was also significantly upregulated, denoting effective activation of the antioxidant system. To some extent, these results provide metabolic insights into the adaptive response mechanism of P. haitanensis to short-term enhanced UV-B radiation.     

The effects of feeding α-amylase-enhanced corn silage with different dietary starch concentrations to lactating dairy cows on milk production,nutrient digestibility,and blood metabolites

Corn silage is one of the most common ingredients fed to dairy cattle. Advancement of corn silage genetics has improved nutrient digestibility and dairy cow lactation performance in the past. A corn silage hybrid with enhanced endogenous α-amylase activity (Enogen, Syngenta Seeds LLC) may improve milk production efficiency and nutrient digestibility when fed to lactating dairy cows. Furthermore, evaluating how Enogen silage interacts with different dietary starch content is important because the ruminal environment is influenced by the amount of rumen fermentable organic matter consumed. To evaluate the effects of Enogen corn silage and dietary starch content, we conducted an 8-wk randomized complete block experiment (2-wk covariate period, 6-wk experimental period) with a 2 × 2 factorial treatment arrangement using 44 cows (n = 11/treatment; 28 multiparous, 16 primiparous; 151 ± 42 d in milk; 668 ± 63.6 kg of body weight). Treatment factors were Enogen corn silage (ENO) or control (CON) corn silage included at 40% of diet dry matter and 25% (LO) or 30% (HI) dietary starch. Corn silage used in CON treatment was a similar hybrid as in ENO but without enhanced α-amylase activity. The experimental period began 41 d after silage harvest. Feed intake and milk yield data were collected daily, plasma metabolites and fecal pH were measured weekly, and digestibility was measured during the first and final weeks of the experimental period. Data were analyzed using a linear mixed model approach with repeated measures for all variables except for body condition score change and body weight change. Corn silage, starch, week, and their interactions were included as fixed effects; baseline covariates and their interactions with corn silage and starch were also tested. Block and cow served as the random effects. Plasma glucose, insulin, haptoglobin, and serum amyloid A concentrations were unaffected by treatment. Fecal pH was greater for cows fed ENO versus CON. Dry matter, crude protein, neutral detergent fiber, and starch digestibility were all greater for ENO than CON during wk 1, but differences were less by wk 6. The HI treatments depressed neutral detergent fiber digestibility compared with LO. Dry matter intake (DMI) was not affected by corn silage but was affected by the interaction of starch and week; in wk 1, DMI was similar but by wk 6, cows fed HI had 1.8 ± 0.93 kg/d less DMI than LO cows. Milk, energy-corrected milk, and milk protein yields were 1.7 ± 0.94 kg/d, 1.3 ± 0.70 kg/d, and 65 ± 27 g/d greater for HI than LO, respectively. In conclusion, ENO increased digestibility but it did not affect milk yield, component yields, or DMI. Increasing dietary starch content improved milk production and feed efficiency without affecting markers of inflammation or metabolism.     

离子色谱同时测定果汁中22种糖、糖醇和醇

目的建立积分安培-离子色谱法同时测果汁中22种糖、糖醇和醇定的方法。方法在流速为0.40 mL/min, pH值在6.5～8.6,柱温为30℃条件下,在CarboPacTM MA1(4 mm×250 mm)色谱柱中进行分离。结果 22种组分在测定浓度范围内具有良好的线性关系(r~20.999);除了甲醇外,其他21种组分检出限在0.006～0.203 mg/L之间;在0.50、1.00、5.00 mg/L 3个添加浓度水平下,回收率为75.83%～105.89%,相对标准偏差(RSD)在1.03%～10.39%范围内。结论该方法简便、快速、准确、灵敏,完全适于果汁中22种糖、糖醇和醇的分析测定。