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11.
麦胚高蛋白乳粉的研制及营养评价 总被引:1,自引:0,他引:1
研究了用麦胚浆液与牛乳混合生产高蛋白奶粉的方法。产品的主要特点是具有较高含量的赖氨酸,谷胱甘肽,磷脂,胆碱,不饱和脂肪酸等,这些成分对人体具非了非常的好健脑,抗衰老作用。 相似文献
12.
Afam I Jideani Richard K Owusu Apenten H G Muller 《Journal of the science of food and agriculture》1994,65(4):465-476
The effect of cooking on proteins from acha and durum wheat was assessed from an analysis of protein extractability, gel electrophoretic profiles, in-vitro protein digestibility (IVPD) and the amino acid compositions of wholemeal flour and residue proteins. Heating wholemeal flour samples at 100–140°C (t = 10–40 min) resulted in 0–30% and 45–55% decreases in acha and durum protein solubility, respectively. In general, high molecular weight (30–70 k Da) protein subunits were more susceptible to heat damage. For both cereals, sodium dodecyl sulphate (SDS; 10 g litre?1) and/or dithiothrcitol (DTT; 10 mM ) increased protein solubility in unheated and heated samples. The IVPD index was 90–91% and was not significantly altered by cooking (100–120°C, t = 40 min). Cooking at extreme temperatures (140°C, t = 40 min) reduced the IVPD by 8% (P = 0.05). Osborne fractionation resulted in a durum or acha residue level of 7.8% or 55.2%. Treatment with solvent containing propanol, SDS and/or DTT at room temperature followed by SDS-polyacrylamide gel electrophoresis of non-solubilised proteins showed that the glutelin fraction of acha, with the exception of a 65 kDa subunit, was insoluble owing to strong inter-subunit hydrophobic and disulphide interactions. Wholemeal acha flour and residue protein showed a significantly greater level of hydrophobic and sulphur amino acids as well as glutamine which is associated with H-bonding. The possibility that cereal protein solubility is also dependent on protein-carbohydrate links is discussed. 相似文献
13.
MALHIREDDY INDUMADHAVI V. AGTE 《International Journal of Food Science & Technology》1992,27(2):221-228
The average diet in most developing countries is predominantly cereal based. Wheat, rice and millets are major staple foods. Although these diets are sufficient in iron, their low bioavailability is one of the most significant factors for iron deficiency anaemia. Traditional techniques like fermentation show promise in improving iron bioavailability. In vitro ionizable iron was estimated in 31 different combinations of rice, wheat, sorghum, black gram, bengal gram, green gram and coriander in five replicates with or without, fermentation in steamed products. Results indicate that in general cereal pulse combination and fermentation significantly ( P <0.05) increase the per cent ape of ionizable iron. Combination effects dominated in rice whilst fermentation dominated in sorghum. There was a significant reduction ( P <0.05) in phytate phosphorus on fermentation but no loss of tannin. 相似文献
14.
15.
Alkylated ureas: mineralization and evaluation as N sources 总被引:2,自引:0,他引:2
An incubation experiment was conducted for 11 weeks to study the mineralization of ten alkylated ureas and urea in soil. Six of the alkylated ureas viz. methylurea(MU), 1,3-dimethylurea(1,3DMU), 1,1-dimethylurea(1,1DMU), ethylurea(EU), 1,3-diethylurea(1,3DEU) and butylurea(BU) and urea mineralized during the experiment. Urea mineralized immediately, while alkylated ureas mineralized after an incubation period ranging from less than a week to four weeks (delay period of mineralization). The delay period increased in the following sequence MU < 1,3DMU < EU < BU < 1,1DMU < 1,3DEU, but after the delay period was over the compounds mineralized almost as rapidly as urea. The delay period varied according to the number of carbon atoms in the alkyl group and their position with respect to each other on the molecule. It appeared to be specific for each compound and was apparently not influenced by the presence of urea or other alkylated ureas. This character can be used to develop mixture of various alkylated ureas to obtain N mineralization at the desired time. Rapid evolution of CO2 and N2O was observed during the mineralization of urea as well as alkylated ureas. Increase in soil pH was also observed during this period. The simultaneous ocurrence of these events suggested the formation of urea as an intermediate during the mieralization of alkylated ureas. None of the alkylated ureas showed adverse affect on emergence of wheat seedlings and except DEU and BU at high concentration no other alkylated urea showed any adverse effect on initial growth of wheat seedlings. 相似文献
16.
Ning Wang Jun Chen Qi Zhou Lianzhou Jiang Liqi Wang Yingjie Dai Dianyu Yu Walid Elfalleh 《European Journal of Lipid Science and Technology》2021,123(6):2000091
Crude wax extracted from rice bran oil (RBO) is used to improve the oleogel properties and oxidative stability of RBO. The effect of crude rice bran wax (CrBW) on the formation characteristics and oxidative stability of oleogels is discussed. The results show that oleogels can be formed with 7.0 wt% CrBW at 20 °C. As the concentration of CrBW increases from 7.0 to 11.0 wt%, the hardness and solid fat content (SFC) of the oleogels increase significantly, and the oleogels are primarily β' crystals. Moreover, oleogel crystals formed with 5 and 7 wt% CrBW are flocculent; when the amount included is 9%, the oleogel crystals are transformed into long dendrites, and the density rises. After 90 days of storage at 20 °C, the peroxide value of oleogels formed with 9.0 wt% CrBW slowly rises from 3.21 to 6.52 mmol kg−1. Practical Applications: Oleogels prepared here by CrBW and RBO are an innovative structural lipid without trans fats. Useful information on the rich fats and nutrients in CrBW is provided, which reduces the production cost and improves the industrial production capacity. 相似文献
17.
Simulation of nitrogen dynamics and biomass production in winter wheat using the Danish simulation model DAISY 总被引:14,自引:0,他引:14
S. Hansen H. E. Jensen N. E. Nielsen H. Svendsen 《Nutrient Cycling in Agroecosystems》1991,27(2-3):245-259
A dynamic simulation model for the soil plant system is described. The model includes a number of main modules, viz., a hydrological model including a submodel for soil water dynamics, a soil temperature model, a soil nitrogen model including a submodel for soil organic matter dynamics, and a crop model including a submodel for nitrogen uptake. The soil part of the model has a one-dimensional vertical structure. The soil profile is divided into layers on the basis of physical and chemical soil characteristics. The simulation model was used to simulate soil nitrogen dynamics and biomass production in winter wheat grown at two locations at various levels of nitrogen fertilization. The simulated results were compared to experimental data including concentration of inorganic nitrogen in soil, crop yield, and nitrogen accumulated in the aboveground part of the crop. Based on this validation it is concluded that the overall performance of the model is satisfactory although some minor adjustments of the model may prove to be necessary. 相似文献
18.
预处理方式对小麦秸秆制备高吸水性树脂的影响 总被引:5,自引:2,他引:5
以小麦秸秆为原料合成高吸水性树脂需首先对秸秆进行预处理,通过实验分析,比较了预处理方式如酸处理、碱浸泡、氨水浸泡、碱蒸煮及其联合处理对秸秆及高吸水性树脂的影响;用晶相显微镜、IR等表征了处理前后秸秆的微观形貌、化学结构及树脂的化学结构等;结果表明,比较理想的预处理方式是碱蒸煮处理〔w(NaOH)=14%的水溶液、150℃、0.6 MPa、30 m in〕结合浓度为1 mol/L的硝酸在100℃下处理30 m in,及w(NH3.H2O)=10%的氨水室温浸泡48 h结合浓度为1 mol/L的硝酸在100℃下处理45 m in;两种方式所得高吸水性树脂吸收纯水的质量倍率分别为405 g/g和293 g/g,吸收w(复混肥)=0.1%的水溶液的质量倍率分别为124 g/g和82g/g〔复混肥中w(N)=w(P)=w(K)=10%,N、P、K分别以尿素、过磷酸钙、氯化钾存在〕。 相似文献
19.
20.
Mussoorrie rock phosphate (MRP), MRP + pyrite (25% by weight), diammonium phosphate (DAP), ammonium polyphosphate (APP) and nitrophosphate (NP) were compared in a field experiment as fertilizers for wheat. At 20 kg P ha–1, MRP was only 6 per cent as effective as DAP. However, when it was mixed with pyrite, the efficiency of MRP increased to 64 per cent at 20 kg P ha–1 compared with 97 per cent at 40 kg P ha–1. The P requirement for a targeted yield for 4.5 t ha–1 decreased from 39.4 kg P ha–1 as MRP to 23.7 kg P ha–1 as MRP + pyrite. Of the other P fertilizers studied, NP was as effective as DAP, whereas APP was 9 to 37 per cent more effective than DAP. However, the P requirement as DAP, NP and APP for a targeted yield of 4.5 t ha–1 was similar (11 ± 0.5 kg P ha–1). 相似文献