Effect of thermal processing and fermentation with Chinese traditional starters on characteristics and allergenicity of wheat matrix

Wheat allergy has become a serious health threat worldwide and its prevalence has increased alarmingly in the past few years.Factors such as food matrix and food processing may alter the structure of wheat proteins,and hence affect its allergenic properties.However,few reports have focused on the influence of Chinese traditional starter fermentation on wheat allergy.In this study,5 starters from different regions of China were used for fermentation,and protein characteristics were monitored by sodium dodecyl sulfate polyacrylamide gel electropheresis,and immunoreactivity analyzed by immunoassay with allergenic serum was obtained from New Zealand white rabbits.The allergenicity of steamed and baked matrices was also evaluated.The results showed that the allergenicity of wheat dough was basically increased at the beginning and then decreased during fermentation,but specific trends depend on different starters.With the progress of fermentation,especially as pH value decreased to 3.0-4.0,the allergenicity decreased significantly.Baking and steaming can reduce the allergenicity of wheat matrix,but fermentation is not a key factor affecting the allergenic activity of proteins.Our results can provide a theoretical basis for controlling wheat allergenicity in food proces sing or producing hypoallergenic food.

Gastrointestinal Tract Development in Unweaned Calves Feeding Different Amounts of Milk and Different Starters

This study was conducted to determine the effect of different starter diets and different amounts of milk on growth performance and gastrointestinal tract development in unweaned calves. 16 calves were assigned to 4 groups, 4 calves in each group. These four groups received the following treatments respectively: 1) high milk (6 L) + low starch (21%), high NDF (28%), high molasses (10%) starter (HMLS group);2) high milk (6L) + high starch (40%), low NDF (14%), low molasses (5%) starter (HMHS group);3) low milk (3 L) + low starch (21%), high NDF (28%), high molasses (10%) starter (LMLS group);4) low milk (3 L) + high starch (40%), low NDF (14%), low molasses (5%) starter (LMHS group). The trial was of 2 × 2 factorial design. All calves had free access to hay and water. Results showed that the low milk allowance increased calf concentrate dry matter intake (DMI) and total DMI, reduced body height at 4 weeks of age, reduced heart girth at 6 weeks of age (P < 0.05). The low milk allowance increased complex stomach full weight, reticulorumen full weight, and the percentages of stomach full weight and reticulorumen full weight over body weight (P < 0.05). The low starch, high fiber, high molasses starters reduced the complex stomach full weight, the proportion of the complex stomach empty weight over body weight, reticulorumen empty weight, abomasum full weight, the proportion of abomasum empty weight over body weight and reticulorumen volume (P < 0.05). The low milk allowance increased calf intestine length, small intestine full weight, the proportion of small intestine full weight over body weight, but reduced the jejunum villus width (P < 0.05), increased ruminal pH (P < 0.05). The low milk allowance reduced papilla length in rumen anterior ventral blind sac, but increased papilla length in the posterior ventral sac

Usefulness of Natural Starters in Food Industry: The Example of Cheeses and Bread

Natural starters have been extensively used for many centuries to make many different fermented food products from different raw materials: Milk, meat, roots, vegetables, etc. The industrialisation of food production at the end of the 19th century necessitated the use of regular selected starters to standardize the organoleptic characteristics of the final product. As a consequence, during the 20th century, there was a decline in the use of natural starters in Western countries except in the production of local cheeses or sourdough breads. The beginning of this new millennium has witnessed a deep change in consumer demand, in pursuit of quality, safety and pleasure. In this context, natural starters could, in the future, play an important role in the development of fermented products. However, food producers and researchers have first to cope with fundamental problems in the understanding of these complex ecosystems. The dynamic evolution of the microbial population inside the natural starter (its resilience, its genetic and physiological aptitudes) and the consequences on the product are still partially unknown. This document reviews a broad range of articles concerning the use of natural starters with a specific focus on cheeses and breads, and discusses the major stakes for local food production and the consumption of typical products.

Screening of Fermentation Starters for Organic Fertilizer Composted from Chicken Manure

In order to find fermentation starters that can promote rapid and effective composting of chicken manure,shorten the fermentation period,and improve the compost quality,fermentation starters with different microbial combination ratios(C1,C2,C3,C4 and C5) were designed and fermentation experiment was carried out on these five fermentation starters,commercially available organic fertilizer starter(SS),and chicken manure without inoculating fermentation starter. In the process of the fermentation,the changes in the fermentation temperature,water content and pH value were monitored; the effects of organic manure on the germination rate and growth of rapeseed seeds were measured;viable count,water content,and pH value of prepared fermentation starters were measured; main indicators( organic matter,nitrogen,phosphorus,and potassium) of organic fertilizer generated from fermentation were measured. From the indicators,the formula C3 and C4 were better,in the beginning of fermentation,the temperature rose rapidly,and it reached 40 ℃ in the second day; the water content dropped to below 35% in the 18 th day; the pH value underwent the process of declining-rising-stable,and the overall value showed slight rise,but the change was not great( 0-0. 5). C3 and C4 fermentation products had better effects on the germination and growth of rapeseeds. The germination rate of the rapeseed seeds was 100% and 97. 5% and the bud length was 15. 94 mm and 14. 57 mm,respectively,and the root length was45. 97 mm and 39. 44 mm,respectively. The content of organic matter in fermented organic manure was 86. 62% and 85. 17% respectively,and the total content of nitrogen,phosphorus and potassium was 8. 85% and 8. 22% respectively,and the pH was 7. 5 and 8. 0 respectively.All of these complied with the industry standard NY525-2012( organic matter ≥ 45%,and nitrogen,phosphorus,and potassium ≥ 5%,pH 5. 5-8. 5). The fermentation of fresh chicken manure was completed within 20 days,conforming to the requirements of large-scale organic fertilizer production factory for composting chicken manure into organic fertilizer.

Evolution of free amino acids, biogenic amines and volatile compounds in fermented sausages inoculated with Lactiplantibacillus plantarum and Staphylococcus simulans

Lactic acid bacteria and coagulase-negative staphylococci play an important role in the production of fermented sausages,such as inhibiting the growth of undesirable bacteria and antioxidant.In this study,the effects of inoculation with different starter cultures(Lactiplantibacillus plantarum HN108 and Staphylococcus simulans NJ209)on the free amino acids(FAAs),biogenic amines(BAs)and volatile compounds of fermented sausages were investigated using an amino acid analyzer,ultra performance liquid chromatography and gas chromatography-ion mobility spectrometry,respectively.The pH and carbonyl content of the inoculated group was significantly lower than those in the control group(P<0.05).L.plantarum HN108 significantly reduced the content of FAAs and BAs in fermented sausage production(P<0.05),while S.simulans NJ209 promoted the formation of FAAs(especially bitter amino acids)and exhibited slight BAs-reducing activity.In addition,L.plantarum HN108 promoted the formation of volatile compounds such as ketones,alcohols and alkenes in sausages.In conclusion,L.plantarum HN108 could contribute to reducing the content of putrescine and tyramine and forming the desirable flavor compounds in fermented sausages.Thus,L.plantarum HN108 is expected to be a starter culture that can improve the safety and flavor of fermented sausages.

Preparation of lactic acid bacteria compound starter cultures based on pasting properties and its improvement of glutinous rice flour and dough

The effects of 5 lactic acid bacteria(LAB)fermentation on the pasting properties of glutinous rice flour were compared,and suitable fermentation strains were selected based on the changes of viscosity,setback value,and breakdown value to prepare LAB compound starter cultures.The results revealed that Latilactobacillus sakei HSD004 and Lacticaseibacillus rhamnosus HSD005 had apparent advantages in increasing the viscosity and reducing the setback and breakdown values of glutinous rice flour.In particular,the compound starter created using the two abovementioned LAB in the ratio of 3:1 had better performance than that using a single LAB in improving the pasting properties and increasing the water and oil absorption capacity of glutinous rice flour.Moreover,the gelatinization enthalpy of the fermented samples increased significantly.For frozen glutinous rice dough stored for 28 days,the viscoelasticity of frozen dough prepared by compound starter was better than that of control dough,and the freezable water content was lower than that of control dough.These results indicate that compound LAB fermentation is a promising technology in the glutinous rice-based food processing industry,which has significance for its application.

Postnatal Total Serum Protein Concentration Influences the Health and Growth Parameters of Preweaned Female Holstein Friesian Calves

This study focuses on the effect of the total serum protein(TSP)concentrations at 3 days after birth on the health and growth parameters of preweaned female Holstein Friesian calves.A total of 165 female calves were enrolled and evaluated for morbidity which included diarrhea(D),respiratory disease(Rd)and omphalitis(O).Also,calves with more than one disorder in the same time were recorded as multi-morbid.Body weight(BW)was determined at birth,30 and 60 days of age.Blood samples were taken at 3 days after birth and TSP was determined using a digital Brix refractometer.For statistical analysis all female calves based on TSP concentration were grouped into 3 categories:1-TSP≥6.2 g/dL,2-TSP 5.8-6.1 g/dL,and 3-TSP<5.8 g/dL.Overall,the average of TSP concentration was 6.38 g/dL.The prevalence of diarrhea,respiratory disease(Rd)and omphalitis(O)was 16.96%,7.88%and 4.85%respectively,in calves with one disorder and 6.06%in calves with D+Rd,3.64%in calves with Rd+O,3.03%in calves with O+D,and 3.64%in calves with D+Rd+O.As the TSP concentration in calves decreased from≥6.2 g/dL to<5.8 g/dL the calf hood disorders increased in female calves with one disorder and with more than one disorder.The female calves with fair to poor immunity(category 3-TSP<5.8 g/dL)were significantly more likely(OR 6.28,95%CI 2.91-13.5,p value<0.001)to be affected by diseases compared with female calves with excellent immunity(category 1-TSP≥6.2 g/dL).Also BW and average daily gain(ADG)at 30 and 62 days of life decreased as TSP concentrations decreased.The female calves with TSP≥6.2 g/dL at 3 days of life had the greatest BW at 30 and 62 days of age(51.8 kg and 77.1 kg respectively)compared with female calves with TSP<5.8 g/dL at 3 days of life(46.6 and 70.6 kg respectively).Moreover,starter feed intake during the first 30 days of life,31 to 62 days of life and 1 to 62 days of life was greater in female calves with excellent immunity(TSP≥6.2 g/dL)than female calves with good immunity(TSP 5.8-6.1 g/dL)or with fair to poor immunity(<5.8 g/dL TSP).Measuring the TSP at 3 days of calf’s This study focuses on the effect of the total serum protein(TSP)concentrations at 3 days after birth on the health and growth parameters of preweaned female Holstein Friesian calves.A total of 165 female calves were enrolled and evaluated for morbidity which included diarrhea(D),respiratory disease(Rd)and omphalitis(O).Also,calves with more than one disorder in the same time were recorded as multi-morbid.Body weight(BW)was determined at birth,30 and 60 days of age.Blood samples were taken at 3 days after birth and TSP was determined using a digital Brix refractometer.For statistical analysis all female calves based on TSP concentration were grouped into 3 categories:1-TSP≥6.2 g/dL,2-TSP 5.8-6.1 g/dL,and 3-TSP<5.8 g/dL.Overall,the average of TSP concentration was 6.38 g/dL.The prevalence of diarrhea,respiratory disease(Rd)and omphalitis(O)was 16.96%,7.88%and 4.85%respectively,in calves with one disorder and 6.06%in calves with D+Rd,3.64%in calves with Rd+O,3.03%in calves with O+D,and 3.64%in calves with D+Rd+O.As the TSP concentration in calves decreased from≥6.2 g/dL to<5.8 g/dL the calf hood disorders increased in female calves with one disorder and with more than one disorder.The female calves with fair to poor immunity(category 3-TSP<5.8 g/dL)were significantly more likely(OR 6.28,95%CI 2.91-13.5,p value<0.001)to be affected by diseases compared with female calves with excellent immunity(category 1-TSP≥6.2 g/dL).Also BW and average daily gain(ADG)at 30 and 62 days of life decreased as TSP concentrations decreased.The female calves with TSP≥6.2 g/dL at 3 days of life had the greatest BW at 30 and 62 days of age(51.8 kg and 77.1 kg respectively)compared with female calves with TSP<5.8 g/dL at 3 days of life(46.6 and 70.6 kg respectively).Moreover,starter feed intake during the first 30 days of life,31 to 62 days of life and 1 to 62 days of life was greater in female calves with excellent immunity(TSP≥6.2 g/dL)than female calves with good immunity(TSP 5.8-6.1 g/dL)or with fair to poor immunity(<5.8 g/dL TSP).Measuring the TSP at 3 days of calf’s life,offers information directly correlated to an individual calf’s immunity status,their likeliness of morbidity,mortality and body development and overall the effectiveness of the colostrum management program in the dairy farm.life,offers information directly correlated to an individual calf’s immunity status,their likeliness of morbidity,mortality and body development and overall the effectiveness of the colostrum management program in the dairy farm.

通过西门子Starter软件调试G120C变频器

文章介绍了使用西门子变频器调试工具Starter软件对G120C变频器进行调试的过程。其中包括恢复出厂设置、宏应用、软件控制、电机识别、PID压力调节等功能。

Gluten-free flour fermented with autochthonous starters for sourdough production:Effect of the fermentation process

Refined rice flour and wholegrain quinoa and buckwheat flours were used to prepare gluten-free sourdoughs.Two autochthonous LAB strains were isolated,one from quinoa (Limosilactobacillus fermentum Q3) and the other from buckwheat (Lim.fermentum T5).Lactiplantibacillus plantarum ATCC8014 was used as a reference starter.Two fermentation processes were evaluated,a single-step process (30℃,24 h) named SD1,and a daily refreshment process (backslopping for 10 days) named SD2.Sourdoughs were freeze-dried prior to analyses.Pasting properties,pentosan and polyphenol contents,and antioxidant activity were analysed.Flour properties were significantly modified by fermentation.Polyphenol extractability increased during fermentation,which resulted in a higher antioxidant capacity,mainly through a reducing mechanism.Q3 and T5 strains produced the most remarkable modifications of flour properties.Differences were found between both fermentation processes,mainly as a result of the development of different microbiota.The single-step fermentation (SD1) showed to be a simple and appropriate method for improving flour properties.

Effect of inoculating mixed starter cultures of Lactobacillus and Staphylococcus on bacterial communities and volatile flavor in fermented sausages

The objective of this study was to explore the effects of the inoculation of mixed starter cultures of Lactobacillus and Staphylococcus(labeled L-S)on microbial community and flavor in fermented sausages during the ripening process.Culture-dependent(colony count)and culture-independent(high-throughput sequencing)methods were employed to evaluate bacterial communities.Volatile compounds were identified by gas chromatography-mass spectrometry,and the results were analyzed by principal component analysis(PCA).The identified bacteria with high relative abundance included Lactobacillus and Pediococcus,and the relative abundances of Leuconostoc and Weissella in fermented sausages were remarkably decreased at the end of the ripening process.At the end of ripening,2-nonenal,tetradecanal,ethylstearate and terpinyl acetate played substantial roles in the flavor development of the L-S fermented sausages.Sensory evaluation showed a high score in the L-S fermented sausages.Sausages can be inoculated with L-S starter culture to improve the safety and flavor of meat products.

3D printed lactic acid bacteria hydrogel:cell release kinetics and stability

In this study,a new type of 3 D printed living biological hydrogel was developed by integrating lactic acid bacteria(LAB)into biocompatible and non-toxic polymer materials.Interestingly,the living materials loaded with LAB can be freeze-dried and reused for more than 100 times.The bio-hydrogel can be used to co-culture different LAB and keep its fermentation performance stable in long-term use.The release kinetics model and response surface method were used to simulate and optimize the bacteria release mode in the bio-hydrogel.The results show that the release of bacteria from hydrogel is regulated by the coupling of Fickian diffusion and polymer swelling.The stability of LAB hydrogel was evaluated by reuse experiments.The images of confocal microscopy and scanning electron microscope showed that the bacteria with high cell viability were distributed in the hydrogel and intact structure of the living hydrogel was maintained after 100 times of reuse as yoghurt starter.In conclusion,the 3 D printed LAB bio-hydrogel developed in this study has the advantage of reuse and sustainability,which is expected to open up a new way for the preparation of food culture starter.

Composition analysis of acid hydrolysates from Cucurbita moschata Duch.polysaccharides and their effect on oxidative stress resistance of Caenorhabditis elegans

Pumpkin polysaccharides(PPe)have a variety of bioactive effects and our previous research showed the acid hydrolysate(PPe-S,a mixture)from PPe had an antioxidative capacity both in vitro and in viro.The aim of this study was to purify PPe-S and investigate the antioxidant stress effects of 2 purified components(PPe-S-1 and PPe-S-2)using Caenorhabditis elegans as model organism.The results showed that PPe-S-2 had a notable antioxidant effect,and could significantly enhance the activities of antioxidant enzymes including superoxide dismutase(SOD)(P<0.01),catalase(CAT)(P<0.01)and glutathione reductase(GR)(P<0.05),and increase the level of glutathione(GSH)(P<0.01),and decreased the content of malondialdehyde(MDA)(P<0.05).PPe-S-2 could significantly extend the survival time of C.elegans(P<0.01),which were stress-induced by hydrogen peroxide and methyl viologen.PPe-S-2 was a heteropolys accharide composed of glucose,arabinose,rhamnose and galactose with the molar ratio of 1.00:0.03:0.02:0.14.The molecular weight of PPe-S-2 was 0.73 kDa detected by high performance liquid chromatography.These studies demonstrated that PPe-S-2 obtained by the acid hydrolysis of PPe had a prominent protective effect to the damage induced by the intracellular free radical generating agents.

ISG型速度耦合混合动力系统全局最优控制方法

混合动力系统具有节能和环保优势,为了提高混合动力系统的燃油经济性,结合ISG(integrated starter generator)型速度耦合混合动力系统的结构,构建了系统动力学模型。利用动态规划方法,设计了以发动机节气门开度和电机转矩为控制变量,以发动机转速和电池SOC等为状态变量,以整个循环发动机燃油消耗最低为目标函数,电池SOC维持平衡和限制频繁换挡为附加代价函数的动态规划算法。仿真结果表明:与传统的基础车型相比,混合动力系统燃油经济性提高了35.5%。

RESEARCH OF THE SWITCHED RELUCTANCE STARTER/GENERATOR SYSTEMS

This paper focuses on the simulation and test of the switched reluctance starter/generator systems. Through the emulational analysis of the initial starting torque, the optimal turn-on section of the power switches is discovered. The fundamental theory of the generating operation is analyzed with the linearity model, and a new method is presented based on voltage pulse width modulation for the generating mode control. Through the steady-state and optimized emulation of the output power and system efficiency, the optimizational control approach for the generating mode over a wide speed range is introduced. At last, the test of the 3KW prototype system shows that the dynamic and static performance of this system is fine.

SINAMICS G120变频器的2线、3线控制

Siemens A&D推出新一代集成式变频器SINAMICS G120。全新的模块化变频器,集成了故障安全保护功能和通用的现场总线通讯,并具有再生能量回馈功能,是一款更加灵活可靠的变频器。通过对G120变频器调试,阐述了如何应用利用STATER软件配置系统参数,设置变频器的2线,3线控制方式,并详细阐述2线,3线控制方式的控制时序。

利用Community Starter Kit构建Web网站

随着网络技术的发展,越来越多的网站采用ASP.NET为工具进行开发,但由于其复杂性使很多开发者望而却步,为了能够让开发者能够快速的构建W eb站点,M icrosoft推出了ASP.NET StarterK it,这里对ASP.NET Starter K it进行了描述,并用其中的Community Starter K it构建了一个具有评价、用户投票、上载配额、更改通知和主题的W eb站点。

SINAMICS S120在上悬卸料离心机上的应用

文章采用SINAMICSS120DC/AC共直流母线的多轴驱动器拖动两台上悬全自动卸料离心机的方式,弥补了以往带能量回馈变频器"一拖二"的缺陷。采用一台S7-300PLC控制两台离心机的工艺过程,使两台离心机工作状态信号在内部传递,更便于用一台触摸屏对两台设备进行操作,也便于用WinCC等数据采集与监控软件的组态及简化与S7-300PLC相连的拓扑结构。在实际的使用中发挥了高效节能、自动化程度高等优势,具有广泛的应用前景。

一类新的最优变重量光正交码

变重量光正交码用于光码分多址通信系统以满足不同服务质量用户需求。本文证明了当整数v≡25(mod 50)且v>25时存在最优(v,{3,5},1,{5/6,1/6})变重量光正交码。

利用微软Community Starter Kit创建图书馆网站

微软ASP.NET技术用在开发网站上具有代码安全、开发速度快等优点,但开发人员很常掌握这项技术的所有特点以及这项技术带来的优势。ASP.NET Starter Kit(asp.net启动工具包)为开发者提供了ASP.NET和.NET framework一个非常好的途径,通过该启动工具包能建立一个完整的应用程序解决方案。该文采用启动工具包里面的Community Starter Kit案例来开发图书馆网站。通过较长时间运行,该网站表现出很好的稳定性和实用性。

(6×v,{3,4},1,Q)光正交码的构造

光正交码(OOC)是光码分多址通信系统的基础,二维光正交码比一维光正交码具有更好的性能。二维变重量光正交码目前研究结果少。本文利用斜Starter构造了两类二维变重量光正交码(6×v,{3,4},1,(4/5,1/5))-OOC和(6×v,{3,4},1,(2/3,1/3))-OOC,其中第一类是最优的,第二类码字个数比理论上界少3个。