Modification of the rheological behavior of amaranth (Amaranthus hypochondriacus) dough

For people with celiac disease, a lifelong abdication of gluten including-products is necessary to live a life without celiac affected reactions. The production of high-quality bread from gluten free flour is not simple in comparison to gluten including flours such as those derived from wheat (Triticum spp.). The gas binding and crumb structure forming capacity are very low in gluten free batters. They can efficiently be analyzed through the rheological properties of the dough used. The use of acidification in amaranth (Amaranthus hypochondriacus) dough preparation is a possible means of changing the rheological behavior of amaranth in the desired direction. Methods include the use of lactic acid directly, or the fermentation via lactic acid bacteria. Adding up to 20 mL lactic acid/kg flour in amaranth dough preparation led, during oscillation tests, to an increase of the complex shear modulus up to 30% in the range of 0.1 up to 10 Hz. The use of sourdough fermentation decreased the complex shear modulus in the same test up to nearly 60%. In creep recovery tests, the elastic part of amaranth dough decreased from 65.4% without any treatment down to 63.9% by the addition of up to 20 mL lactic acid/kg flour. Sourdough fermentation by Lactobacillus plantarum was able to decrease it to 54%. The acidification showed a significant positive influence on the rheological parameters of amaranth dough only at the higher stress level. In contrast, sourdough fermentation was able to produce doughs with viscosity and elasticity similar to that found in pure wheat flours.     

开食料中粗蛋白质水平对荷斯坦犊牛养分消化率和氮代谢的影响

为研究开食料中粗蛋白质水平对断奶犊牛营养物质消化率及氮平衡的影响,本试验选取15头荷斯坦公犊牛分别饲喂粗蛋白质水平为16.22%(低蛋白质组)、20.21%(中蛋白质组)和24.30%(高蛋白质组)的开食料。开食料采用限饲,试验在犊牛的8～16周龄进行,在10周龄和13周龄时,每组分别选取3头牛进行代谢试验。试验期为7d,采取全收粪法。结果表明,10周龄时,除粗蛋白质外,低蛋白质组的其他营养物质消化率均高于另外两组。13周龄时,除干物质外,其他营养物质的消化率均随日粮粗蛋白质水平升高而升高。犊牛的粪氮、尿氮、吸收氮、沉积氮和氮的总利用率随开食料中粗蛋白质水平的升高而升高。由此可得,日龄对犊牛营养物质的消化率存在影响,犊牛的吸收氮和沉积氮随开食料中粗蛋白质水平的升高而升高,但氮的排放也会随之升高。     

抗鸡传染性法氏囊病病毒冻干卵黄抗体与同类产品的比较试验

本研究鸡传染性法氏囊病冻干卵黄抗体和市售精制液体卵黄抗体分别以10羽份和3 mL超剂量肌肉注射各10只18日龄SPF雏鸡,观察14 d均安全。两种抗体以1羽份剂量分别肌肉注射各20只18日龄SPF雏鸡24 h后,用IBDV强毒TL株攻击,连续观察144 h,2个试验组分别有20/20、17/20的雏鸡健活,剖检没有发现法氏囊病变;二者分别以1羽份剂量连续2 d肌肉注射各20只18日龄已经被IBDV强毒TL株攻击12 h的SPF雏鸡,连续观察96 h,2个试验组有19/20、17/20的雏鸡健活,而预防和治疗试验中的阳性对照组中20只鸡均有法氏囊特征性病变发生（20/20）,且死亡率在85%（17/20）以上,阴性对照组雏鸡均正常。     

戊糖片球菌的益生功能及其在食品科学领域中的应用

介绍了戊糖片球菌的抑制食源性致病菌、调节肠道免疫功能、降低胆固醇、抗肿瘤等益生功能,综述了其微生物制剂在食品科学领域中的应用,主要包括发酵肉制品、乳制品和蔬菜,并对其研究前景进行了展望。     

几种微生物发酵剂对风鸭挥发性风味化合物的影响

【目的】探讨几种微生物对风鸭挥发性风味化合物的影响,为肉制品发酵剂的开发提供理论依据。【方法】分别以米酒乳杆菌（Lactobacillus sake）、木糖葡萄球菌（Staphylococcus xylosus）和德汉逊氏酵母菌（Dabaryomyces Hansenula）为发酵剂生产风鸭,采用顶空固相微萃取和气质联用（HS-SPME/GC-MS）对发酵风鸭肌肉中的挥发性风味化合物种类和相对含量进行测定。【结果】共检测到风味化合物117种,主要包括酸10种、醛20种、醇17种、酮14种、酯类27种、烃20种、酚类2种和杂环7种。其中对照中检测到64种风味化合物,米酒乳杆菌、木糖葡萄球菌和德汉逊氏酵母菌处理中分别检测到69、69和73种风味化合物。在各处理中,对照样品中烃类含量较高,米酒乳杆菌处理中酸的含量较高,木糖葡萄球菌处理中醛的含量较高,而德汉逊氏酵母菌处理中醇和酯的含量高。【结论】微生物对风鸭挥发性风味化合物的种类和含量都产生了非常明显的影响。这些挥发性风味化合物对风鸭特有风味的形成起到了重要作用。     

Effect of wheat processing on rumen characteristics and rumen parameters in Holstein‐Friesian calves

In this experiment, effect of wheat processing on rumen conditions and development were investigated. Fifty‐six neonatal Holstein‐Friesian calves (22 male and 34 female) were fed calf starters and post‐weaning diets containing 35 (pre‐weaning) and 21.90% (post‐weaning) popped wheat (PW), steam‐flaked wheat (SFW), dry‐rolled wheat (DRW) or ground wheat (GW) till 12 weeks of age. Calves were weaned at the end of 9th week, and a post‐weaning‐specific starter diets were fed for 1 month. Rumen liquor was analysed in days 30, 60 and 90 of the experiment to determine volatile fatty acids (VFA), pH and ammonia nitrogen concentrations. Twelve male calves (three calves/treatment) were slaughtered, and digestive tract was emptied. Forestomach empty weight and rumen parameters were assessed. Results indicated that calves received PW had the highest total VFA, acetate, propionate, butyrate, ammonia nitrogen, rumen wall thickness, papilla width and density. Calves fed DRW experienced the lowest rumen pH throughout the experiment probably because high proportion of fine particles in GW. Calves consuming PW apparently had more functional rumen in comparison with other groups.     

Forage and sugar in dairy calves' starter diet and their interaction on performance,weaning age and rumen fermentation

The effects of sugar and forage inclusion in calves' starter and their interaction on animal performance and rumen fermentation parameters were investigated. Twenty‐eight neonatal Holstein male calves 3 days of age with average body weights of 42 ± 4 kg were allocated to four different treatments. All calves were fed a similar basal diet consisting of milk and concentrate. The experimental treatments were: (i) basal diet with no supplementation (Control, hereafter designated by C), (ii) basal diet plus 5% granular sugar cane (Sugar, designated by S), (iii) basal diet plus 5% forage (Forage, designated by F) and (iv) basal diet plus 5% forage with 5% granular sugar cane (F × S). Supplement ingredients were used on a dry matter (DM) basis. Rumen fluid parameters were measured twice on days 35 and 70 of the study period. The calves were weaned when they could consume 1 kg of starter for three consecutive days. The results show that starter intake was not affected by treatment; however, the lowest ADG was observed with calves in the sugar treatment. Weaning age was affected by treatments, and forage showed to reduce milk consumption period down to its shortest. Forage–sugar interaction was found to have no effects on animal performance. The structural body indices as well as the health status of the calves were similar in different treatments. Rumen pH did not differ among the treatment groups. Among the rumen parameters, total VFA concentration and molar proportions of butyrate and propionate did not exhibit any significant differences among the treatments. However, ruminal acetate concentration decreased in calves that fed sugar cane during the early weeks of the study period. Comparison of forage and sugar included in the starter diets revealed that forage reduced weaning age, while sugar cane had a negative effect on calves' performance.     

Nutritional Evaluation of a High-Oil Sunflower Meal in Broiler Starter Diets

Two experiments were conducted with broiler chicks to determine the nutritive value of high-oil sunflower meal (HO-SFM), a sunflower oil extraction by-product obtained through screw-press extraction and expanding processes with a proximate composition of 32% CP, 12% crude fiber, and 19% ether extract. In Experiment 1, the effects of a high level (46.4%) of HO-SFM on chick performance and gastrointestinal organs were tested. The objective of Experiment 2 was to determine if pelleting the feed could overcome the bulkiness resulting from inclusion of HO-SFM at a high level. The results of Experiment 1 indicated that addition of 46.4% HO-SFM to broiler starter diets significantly (P < 0.05) depressed body weight, feed intake, and gain but not feed conversion. Fat pad and liver lipid were again significantly (P < 0.05) decreased in the HO-SFM treatment. Impaired performance might have been due to the difference of the density of HO-SFM diet (608 g/L) compared with the soybean meal control (723 g/L). When bulkiness was overcome by pelleting in Experiment 2, it was found that pelleting the feed significantly enhanced growth of broiler chicks compared with SFM or soybean meal mash diets. Liver weights and lipid content were again decreased in HO-SFM diets. The results of this study suggest that HO-SFM can be used up to 28% without adverse effects on broiler chicks. Further improvement was observed with pelleting. Liver weight and lipid content were consistently reduced by feeding HO-SFM.     

Effect of starter fertilizers on the yield and quality of lettuce grown on peaty soils

Abstract. Increasing concerns for the financial and environmental impact of the use of broadcast fertilizer by the UK horticultural industry is leading to the development of alternative application techniques, which aim to reduce inputs through improved efficiency. One such technique, 'starter' fertilizer, was investigated with drilled and transplanted crisp lettuce ( Lactuca sativa ) on two fertile peaty soils. Starter fertilizers injected below the seed of the drilled crop, or as spot applications around the planting module, were tested alone and in various combinations with different rates of broadcast fertilizer. The work extended previous findings, based largely on mineral soils, and demonstrated that high yields of iceberg quality lettuce can be achieved with reduced inputs of broadcast fertilizer, and that there can be additional benefits of earlier maturity and improved quality. It is concluded that starter fertilizer can contribute to the development of environmentally beneficial farming practices whilst maintaining the productivity and competitiveness of the horticultural industry.     

中和培养法制备高浓度乳酸菌发酵剂的研究

为制备高浓度乳酸菌发酵剂,运用化学中和法对乳酸菌进行浓缩培养研究。试验结果表明,以脱脂乳粉+酵母粉作为生长培养基,接种量为2%(嗜热链球菌和保加利亚乳杆菌的接种量各为1%),培养温度39℃,培养过程用质量浓度为4mg/L的NaOH溶液作为中和剂,将pH值控制在5.4或5.0,培养7h以后,可以使乳酸菌活菌数的对数值达到8～9。与普通的液体发酵剂相比,获得了显著浓缩效果。