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61.
Aquafaba, the viscous liquid resulting from cooking chickpeas in water is typically discarded. However, this solution is now widely used by the vegan community as an egg replacement that adds texture to food products, such as mayonnaise, pudding, ice cream and baked goods. Sponge cake was prepared with either egg white or aquafaba derived from ten different brands of canned chickpea and the texture and colour were compared. Aquafaba obtained from each chickpea can produced foam which differed in both properties and stability. In addition, aquafaba from some brands provided comparable foam volume and stability to that achieved with egg white. The colour and texture of sponge cake made with either egg white or aquafaba were similar and acceptable, but cakes prepared with aquafaba were less springy, and less cohesive than cake that included egg white. Based on our results, it appears that aquafaba has potential to replace egg white in eggless cake recipes.  相似文献   
62.
Dental caries is a highly prevalent disease caused by colonisation of tooth surfaces by cariogenic bacteria, such as Streptococcus sobrinus and Streptococcus salivarius. Reducing initial adherence of such bacteria to teeth may delay onset of caries. Many foods, such as milk, can inhibit microbial adherence. In this investigation, the effect of untreated (UT) and enzyme-treated (ET) dairy powders on adherence of S. sobrinus and S. salivarius to hydroxylapatite (HA), an analogue of tooth enamel, was examined. Untreated (UT) acid whey protein concentrate (AWPC) 80 inhibited streptococcal adherence to phosphate-buffered saline-coated HA (PBS-HA) and saliva-coated HA (S-HA) by >80% at ?31.25 μg mL−1. UT sweet WPC80, buttermilk powder and cream powder also significantly reduced adherence (P < 0.05). Enzyme-treatment of all dairy powders reduced their anti-adhesion activity. However, ET sweet WPC80 significantly inhibited growth of these streptococci (P < 0.05) at ?0.6 mg mL−1. Therefore, dairy powders may reduce progression of dental caries by their anti-adhesion and/or antibacterial activity.  相似文献   
63.
This experiment was carried out with 58-week old laying quails (Coturnix coturnix japonica) assigned to four treatment groups with eight quails per replication in six repetitions in a completely randomized design. The treatments consisted of diets with different levels of flaxseed (0, 1.5, 3.0, and 5.0%). The amounts of cholesterol and total lipids and the fatty acid composition of quail egg yolk were determined in four 21-day cycles. No difference was found in cholesterol levels between the four treatments and the four cycles. The increased ingestion of linolenic acid (LNA) in diet reduced the formation of arachidonic acid (AA) significantly. The 3.0 and 5.0% treatment groups presented a reduction in total saturated fatty acids (TSFA) with the increase in percent flaxseed in feed comparatively to the control value. The n-3 fatty acid level was high in all treatments when compared to that of the control group. The n-6/n-3 ratio decreased from 21.30 (control) to 4.52 (5.0%), which is a better value from the nutritional viewpoint.  相似文献   
64.
65.
REFLICS: Real-time flow imaging and classification system   总被引:1,自引:0,他引:1  
An accurate analysis of a large dynamic system like our oceans requires spatially fine and temporally matched data collection methods. Current methods to estimate fish stock size from pelagic (marine) fish egg abundance by using ships to take point samples of fish eggs have large margins of error due to spatial and temporal undersampling. The real-time flow imaging and classification system (REFLICS) enhances fish egg sampling by obtaining continuous, accurate information on fish egg abundance as the ship cruises along in the area of interest. REFLICS images the dynamic flow with a progressive-scan area camera (60 frames/s) and a synchronized strobe in backlighting configuration. Digitization and processing occur on a dual-processor Pentium II PC and a pipeline-based image-processing board. REFLICS uses a segmentation algorithm to locate fish-egg-like objects in the image and then a classifier to determine fish egg, species, and development stage (age). We present an integrated system design of REFLICS and performance results. REFLICS can perform in real time (60 Hz), classify fish eggs with low false negative rates on real data collected from a cruise, and work in harsh conditions aboard ships at sea. REFLICS enables cost-effective, real-time assessment of pelagic fish eggs for research and management. Received: 12 April 2000 / Accepted: 6 July 2000  相似文献   
66.
用结英期蚕豆苗(荚果可供采青豆食用)植株上30厘米左右之嫩梢制作的叶蛋白饲料,适口性良好.用4%的蚕豆苗叶蛋白饲料等量取代产蛋鸡饲粮中的鱼粉(1.5%)和焙炒大豆(2.5%)时,对产蛋鸡的生产性能无明显影响(P>0.05),但极显著地改善了蛋黄色泽等级(P<0.01)、降低了软破蛋率,从而显著地改善了鸡蛋品质,提高了养鸡经济效益.  相似文献   
67.
在螳螂孵化前,调查了螳螂卵囊在柞蚕场中的水平分布格局。经卡平方检验和5种聚集指标的测定结果表明,螳螂卵囊的空间分布型属于聚集分布中的负二项分布,即在柞林间的分布特点表现为极不均匀的嵌纹分布,种群中个体在发生概率上是不相同的,样方内一个个的存在,增加了同样方内其他个体发生的概率。  相似文献   
68.
Under environmental conditions, wild birds can be exposed to multiple stressors including natural toxins, anthropogenic pollutants and infectious agents at the same time.This experimental study was successful in testing the hypothesis that adverse effects of cyanotoxins, heavy metals and a non-pathogenic immunological challenge combine to enhance avian toxicity. Mortality occurred in combined exposures to naturally occurring cyanobacterial biomass and lead shots, lead shots and Newcastle vaccination as well as in single lead shot exposure. Mostly acute effects around day 10 were observed. On day 30 of exposure, there were no differences in the liver accumulation of lead in single and combined exposure groups. Interestingly, liver microcystin levels were elevated in birds co-exposed to cyanobacterial biomass together with lead or lead and the Newcastle virus. Significant differences in body weights between all Pb-exposed and Pb-non-exposed birds were found on days 10 and 20. Single exposure to cyanobacterial biomass resulted in hepatic vacuolar dystrophy, whereas co-exposure with lead led to more severe granular dystrophy. Haematological changes were associated with lead exposure, in particular. Biochemical analysis revealed a decrease in glucose and an increase in lactate dehydrogenase in single and combined cyanobacterial and lead exposures, which also showed a decreased antibody response to vaccination.The combined exposure of experimental birds to sub-lethal doses of individual stressors is ecologically realistic. It brings together new pieces of knowledge on avian health. In light of this study, investigators of wild bird die-offs should be circumspect when evaluating findings of low concentrations of contaminants that would not result in mortality on a separate basis. As such it has implications for wildlife biologists, veterinarians and conservationists of avian biodiversity.  相似文献   
69.
酶水解是降低食物过敏原致敏性的一种常用手段,本文分别利用胃蛋白酶、木瓜蛋白酶、中性蛋白酶和碱性蛋白酶水解鸡蛋清蛋白,通过三羟甲基氨基甘氨酸-十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(Tricine-SDS-PAGE),并结合水解度(邻苯二甲醛法)分析监测蛋清蛋白的酶解过程,进一步利用制备的兔抗蛋清蛋白多克隆抗体血清和鸡蛋过敏患者血清池评估酶解产物的抗原性和致敏性。结果表明:木瓜蛋白酶和碱性蛋白酶能够有效的水解蛋清蛋白,并且所得酶解产物的抗原性和致敏性较低,其中,木瓜蛋白酶水解蛋清蛋白后产物的抗原性降低了59.23%,致敏性降低了4.91%;碱性蛋白酶水解蛋清蛋白后产物的抗原性降低了57.61%,致敏性降低了4.55%。因此,木瓜蛋白酶和碱性蛋白酶对鸡蛋清蛋白降解及致敏性降低方面均有显著影响。   相似文献   
70.
In the marine polychaete, Platynereis dumerilii, reproductive behavior in the two sexes is synchronized by the consecutive discharge of male and female sex-specific pheromones. After the female releases the eggs into the free water column, immediate fertilization is achieved by several males circling around the eggs emitting sperm clouds. We report the isolation and identification of the sperm-release pheromone present in the coelomic fluid of sexually mature females. Each step in isolation was guided by bioassay. Isolation methods included extraction and solvent partitioning and separation methods included ultrafiltration and high-performance liquid chromatography. Uric acid was identified as the sperm-release pheromone that is discharged by the female with release of the eggs. The threshold concentration for sperm release by males was determined as 0.6 M.  相似文献   
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