THE EFFECT OF VARIOUS STARCHES ON THE STABILITY OF BAKING POWDERS

1936 ◽  
Vol 14b (6) ◽  
pp. 204-215 ◽  
Author(s):  
Wilfred Gallay ◽  
Adam C. Bell
Keyword(s):  
Particle Size ◽  
Relative Humidity ◽  
Starch Granule ◽  
Crystal Form ◽  
Physical Effect ◽  
Wheat Starch ◽  
Stabilizing Effect ◽  
Wheat Starches ◽  
The Difference ◽  
The Stability

A study has been made of the stabilizing effect of potato, corn, wheat and rice starches in phosphate, tartrate and combination baking powders under widely differing conditions of storage. The stabilizing effect was found to depend on the size of the starch granule, decreasing efficiency being obtained with increasing granular size in the following order: rice, wheat, corn, potato. Microscopic observations were made to determine the physical effect of the starch. Small wheat granules were found to be more efficient than large ones, and finely powdered wheat starch more efficient than coarse wheat starch. The stability is greater with increasing particle size of acid constituent, and the crystal form of the latter is also important. The difference in stability lent by the various starches is increasingly accentuated with increasing fineness of acid constituent. The stability decreases rapidly with rise in relative humidity. The moisture take-up of potato, corn and wheat starches at different humidities has been measured.

scholarly journals Effect of Potato Pulp Pectic Polysaccharide on the Stability of Acidified Milk Drinks

Molecules ◽  
2020 ◽  
Vol 25 (23) ◽  
pp. 5632
Author(s):  
Weixuan Sun ◽  
Wenhan Yang ◽  
Yuxue Zheng ◽  
Huiling Zhang ◽  
Haitian Fang ◽  
...  
Keyword(s):  
Particle Size ◽  
Zeta Potential ◽  
Neutral Sugar ◽  
Lower Serum ◽  
Pectic Polysaccharide ◽  
Potato Pulp ◽  
Lower Viscosity ◽  
Stabilizing Effect ◽  
New Ideas ◽  
The Stability

In order to broaden the application of potato pulp pectic polysaccharide (PPP) in stabilizing acidified milk drinks (AMDs) and investigate the stabilizing effect and physical properties of AMDs prepared with PPP, a comparative study was made among PPP, commercial high methoxyl pectin (HMP) and low methoxyl pectin (LMP). The zeta potential, rheology, particle size and serum separation of AMDs were evaluated after preparing with PPP, HMP and LMP, respectively. Results indicated that PPP led to lower serum separation than LMP (14.65% for AMDs prepared with 0.5% PPP compared to 25.05% for AMDs prepared with 0.5% LMP), but still higher than HMP (9.09% for AMDs prepared with 0.5% HMP). However, narrower particle size distribution and lower viscosity of AMDs was achieved by PPP than by LMP and HMP. PPP can electrostatically adsorb on the surface of casein and its abundant neutral sugar side chains would provide steric hindrance to prevent casein flocculation in AMDs. Our results might provide some new ideas for the application of PPP in improving the stability of AMDs.

The stability of a periodically heated layer of fluid

1981 ◽  
Vol 110 ◽  
pp. 149-159 ◽  
Author(s):  
John Dowden
Keyword(s):  
Rayleigh Number ◽  
Heated Layer ◽  
Uniform Thickness ◽  
Approximate Relation ◽  
Infinite Layer ◽  
Large Fluctuations ◽  
Stabilizing Effect ◽  
The Mean ◽  
The Difference ◽  
The Stability

The stability of an infinite layer of fluid of uniform thickness at rest with two horizontal boundaries is investigated when the difference between the temperatures at the top and bottom boundaries has a component which is a fluctuating periodic function of time in addition to a constant part. When both boundaries are free small fluctuations have a stabilizing effect on the layer, while large fluctuations tend to make it less stable, consistently with the numerical results of Yih & Li (1972); the effect is attributable entirely to the variation of the temperature gradient with time. An approximate relation between the mean Rayleigh number and the amplitude of the fluctuations is found which separates stable situations from unstable ones. This is compared with the criteria deduced by Homsy (1974) using energy arguments for disturbances of any amplitude.

maize, 1.4-2.7%; of waxy barley, 2.1-8.3%; and of waxy swell only slightly in cold water. Granules differ in size rice 0-2.3%; thus the range of amylose contents of the and shape among plants. For example, corn starch has an waxy wheats is comparable to that of other waxy cereal average diameter of about 15 1.1,M, wheat starch has a bi-grains. Biochemical features of starch from waxy wheats modal size distribution of 25-40 and 5-10 [tm, potato are similar to those of waxy maize [71]. starch has an average size of 40 WTI, and rice starch has an Starch from barley contains 22-26% amylose, the rest average size of 5µm [99]. being amylopectin [28]. However, samples of 11-26% The particle sizes of starch granules have recently re-amylose are known, and starch from waxy barley contains ceived much attention because of their important roles in only 0-3% amylose, while high-amylose starches contain determining both the taste and mouthfeel of fat substitutes up to 45%. and the tensible properties of degradable plastic films. Amylose content of rice is categorized as very low Daniel and Whistler [39] reported that small-granule (0-9%), low (9-20%), intermediate (20-25%), or high starch about 2 !um in diameter, or similar in size to the lipid (25-33%) [124]. The amylose content of long grain rice micelle, had advantages as a fat substitute. Lim et al. [117] ranges from 23 to 26%, while medium grain ranges from investigated the use of starches of different particle size in 15 to 20% and short grain ranges from 18 to 20% [103]. degradable plastic film. They reported that a linear correla-Oat amylose content (16-27%) is similar to that of tion between film thickness and particle size and an in-wheat starch, but oat amylose is more linear and oat amy-verse linear correlation between film thickness and particle lopectin is more branched than that found in wheat [121]. size. Small-granule starches may also be used as face pow-Most sorghum starch is similar in composition to corn der or dusting powder, as a stabilizer in baking powder, and contains 70-80% branched amylopectin and 21-28% and as laundry-stiffening agents. amylose [127]. However, waxy or glutinous sorghum con-The size of the wheat starch granule is 1-30 lam, the tains starch with 100% amylopectin and has unique prop-size distribution being bimodal. Such a bimodal size distri-erties similar to waxy corn [158]. Badi et al. [11] reported bution is characteristic of wheat starch, as well as of rye 17% amylose in starch from one pearl milled population. and barley starches. Wheat starch consists of two basic Gracza [69] reviewed the minor constituents of starch. forms: small spherical granules (about 5-10 wri) and larg-Cereal starches contain low levels of lipids. Usually, the er lenticular granules (about 25-4011m). The small B-gran-lipids associated with starch are polar lipids. Generally, the ules are spherical and have a diameter of less than 10 wrt; level of lipids in cereal starch is between 0.5 and 1%. Be-a mean value of about 4 lam has been reported. The large sides low levels of other minerals, starches contain phos-A-granules are lenticular and have a diameter greater than phorus and nitrogen. In the cereals, phosphorus occurs 10 lam, with a mean 14.11.1m. In reality, the granules have a mostly in the form of phospholipids. The nitrogen is gener-continuous distribution of granule size within the range ally considered to be present as protein, but it may also be designated for that starch. Amylose and amylopectin are a constituent of the lipid fraction. intermixed and distributed evenly throughout the granule. The interaction between amylose and lipids is more Many believe that the composition and properties of small powerful by far than that between amylopectin and lipids and large granules are similar, but this is a subject of some [55]. It is well established that polar lipids (e.g., mono-argument and the subject of many research studies [42]. glycerides, fatty acids, and similar compounds) form a hel-Kulp [110] evaluated the fundamental and bread-mak-ical inclusion complex with the amylose molecule, be-ing properties of small wheat starch granules and com-tween the hydrocarbon chain of the lipid and the interior of pared them with those of regular starch. Small granules the amylose helix. were found to be lower in iodine affinity, indicating differ-ences in amylose levels or some fundamental structural differences. Gelatinization temperature ranges, water-binding capacities, and enzymic susceptibilities of small Starch is laid down in the shape of particles in special amy-granules were higher than those of regular ones. loplast cells in the plant. These particles are called gran-Rice has one of the smallest starch granules of cereal ules, and they are the means by which the plant stores en-grains, ranging in size from 3 to 5 pm in the mature grain, ergy for the carbohydrate in a space-saving way, but also to although the small granules of wheat starch are almost the make the energy easily accessible when the seed germi-same size [33]. The small granule size of that starch results nates [57]. One starch granule is synthesized in each amy-in physical properties that make it useful as a dusting flour loplast, and the shape and size of a starch granule is typical in bakeries. Rice starch amyloses have degree of polymer-of its botanical origin. ization (DP) values of 1000-1100 and average chain Starch granules are relatively dense, insoluble, and lengths of 250-320. These structural properties of amylose

2000 ◽  
pp. 405-432
Keyword(s):  
Particle Size ◽  
Film Thickness ◽  
Starch Granule ◽  
Amylose Content ◽  
Granule Size ◽  
Wheat Starch ◽  
Rice Starch ◽  
Starch Granules ◽  
Small Granule ◽  
Average Size

Use of a Lyophilized Reference Plasma to Compare Coagulation Test Procedures

1975 ◽  
Vol 34 (02) ◽  
pp. 426-444 ◽  
Author(s):  
J Kahan ◽  
I Nohén
Keyword(s):  
Oral Anticoagulant Therapy ◽  
Repeated Measurements ◽  
Test Procedures ◽  
Coagulation Activity ◽  
Close Relationship ◽  
Measured Activity ◽  
Test Materials ◽  
The Difference ◽  
The Stability ◽  
The One

SummaryIn 4 collaborative trials, involving a varying number of hospital laboratories in the Stockholm area, the coagulation activity of different test materials was estimated with the one-stage prothrombin tests routinely used in the laboratories, viz. Normotest, Simplastin-A and Thrombotest. The test materials included different batches of a lyophilized reference plasma, deep-frozen specimens of diluted and undiluted normal plasmas, and fresh and deep-frozen specimens from patients on long-term oral anticoagulant therapy.Although a close relationship was found between different methods, Simplastin-A gave consistently lower values than Normotest, the difference being proportional to the estimated activity. The discrepancy was of about the same magnitude on all the test materials, and was probably due to a divergence between the manufacturers’ procedures used to set “normal percentage activity”, as well as to a varying ratio of measured activity to plasma concentration. The extent of discrepancy may vary with the batch-to-batch variation of thromboplastin reagents.The close agreement between results obtained on different test materials suggests that the investigated reference plasma could be used to calibrate the examined thromboplastin reagents, and to compare the degree of hypocoagulability estimated by the examined PIVKA-insensitive thromboplastin reagents.The assigned coagulation activity of different batches of the reference plasma agreed closely with experimentally obtained values. The stability of supplied batches was satisfactory as judged from the reproducibility of repeated measurements. The variability of test procedures was approximately the same on different test materials.

PREPARATION AND CHARACTERISATION OF ACETYLATED WHEAT STARCH SUPPORTING FOR DIABETES TREATMENT

2018 ◽  
Vol 8 (5) ◽  
pp. 78-84
Author(s):  
Uyen Tran Thi Ngoc ◽  
Nam Nguyen Khac ◽  
Dung Tran Huu
Keyword(s):  
Physicochemical Properties ◽  
Resistant Starch ◽  
Starch Content ◽  
Degree Of Substitution ◽  
Wheat Starch ◽  
Diabetes Treatment ◽  
Glucose Response ◽  
Swelling Capacity ◽  
Wheat Starches

Background: The purpose of the study was to prepare acetylated wheat starches which have amylase hydrolysis resistant capacity to use as functional food supporting for diabetes treatment. Method: Acetate wheat starches were prepared by acetylation reaction of native wheat starch with different mole ratios of acetic anhydride. These starches were determined for the physicochemical properties by 1H-NMR, SEM, X-ray, DSC, solubility and swelling capacity, the resistant capacity by amylase hydrolysis in-vitro. Results: Acetate wheat starches were prepared successfully with the increase in acetyl content and degree of substitution corresponding with the increase of anhydride acetic, which resulted in the change of physicochemical properties of the wheat starches, including constitution, solubility, swelling capacity and contributed to the increase in resistant starch content in the acetate wheat starches. The AC150-9 containing 2.42% acetyl with degree of substitution 0,094 and resistant starch 32,11% is acceptable by FDA guideline about food safety. Conclusion: Acetate wheat starches contain low rate of digestive starch, while containing a higher proportion of resistant starch than natural wheat starch, possessing a high resistance to amylase activities. Thus, it is hope that this kind of starch to control the rapid increase of postprandual blood glucose response for diabetes treatments effectively. Key words: Acetate wheat starch, substitution, DS, RS, amylase

In the stability of paints and varnishes for protective and decorative wood finish

2016 ◽  
Author(s):  
Ю.И. Цой
Keyword(s):  
Organic Solvents ◽  
Evaluation Criteria ◽  
Ternary Systems ◽  
Solubility Parameters ◽  
Formaldehyde Resin ◽  
Film Forming ◽  
The Difference ◽  
Molecular Forces ◽  
The Stability ◽  
Thermodynamic Interaction

Задача получения однородного состава ЛКМ сводится к правильному выбору пленкообразователей и соответствующих растворителей и, в случае необходимости, разбавителей и добавок. На основе положений теории растворимости была проведена оценка совместимости компонентов и стабильности таких систем. Критериями оценки были приняты параметры растворимости и термодинамического взаимодействия. Исследовали совместимость алкидных лаков с аминоформальдегидными смолами в бутаноле, и результаты этих исследований представлены в треугольной фазовой диаграмме. Для оценки совместимости смол по результатам расчета параметров термодинамического взаимодействия были построены спинодали для тройных систем. Как показывает анализ результатов проведенных исследований, даже при большой разности ?? = |?12 – ?13| = 0,2 наблюдается небольшая область несовместимости. С уменьшением разности ?? область несовместимости сужается. При ?23 > ?с область несовместимости расширяется как для ? = 0,2, так и для ?? = 0,1 и ?? = 0. Таким образом, для таких систем на совместимость компонентов, в первую очередь, влияет их взаимодействие между собой – чем оно больше, тем лучше они совместимы. Проведенные исследования показали, что парциальные параметры растворимости, учитывающие природу когезионных сил, более объективно характеризуют растворимость пленкообразующих смол в органических растворителях, чем их общий параметр растворимости. Растворимость пленкообразующих алкидных и этерифицированных аминоформальдегидных смол в органических растворителях обусловлена термодинамическим взаимодействием молекулярных сил различной природы. Стабильность смеси алкидной и этерифицированной аминоформальдегидной смолы в бутаноле обусловлена в большей степени термодинамическим взаимодействием молекулярных сил; при этом степень бутанолизации меламиноформальдегидной смолы оказывает наибольшее влияние на стабильность cистемы. Проведенные исследования по стабильности лакокрасочных смесей из различных пленкообразующих смол на основе рассмотренных критериев оценки могут быть использованы для совершенствования технологии защитно-декоративной отделки древесины. The problem of obtaining a homogeneous composition of the coatings is reduced to the proper selection of film-forming agents, and diluent and, if appropriate, diluents and additives. On the basis of the theory of solubility, we have carried out the assessment of the compatibility of the components and stability of such systems. The evaluation criteria were adopted the parameters of the solubility and thermodynamic interaction. Researched the compatibility with alkyd varnishes aminoformaldehyde resin in butanol, and the results of these studies are presented in the triangular phase diagram. To evaluate the compatibility of the resins according to the results of calculation of thermodynamic parameters of interaction were built spinodal for ternary systems. As the analysis of the results of the studies, even when the difference ??|?12 – ?13| = 0,2 there is a small area of incompatibility. With the decrease of the difference ? ? region incompatibility narrows. When ?23> ?с region incompatibility extends to ?? = 0,2, and for ?? = 0.1 and ?? = 0. Thus, for such systems, compatibility of components, primarily, affects their interaction with each other – the further away it is, the better they are compatible. Studies have shown that the partial solubility parameters, which take into account the nature of cohesive forces, more objectively characterize the solubility of film-forming resins in organic solvents than their total solubility parameter. The solubility and film-forming aminoformaldehyde esterified alkyd resins in organic solvents due to thermodynamic interaction of molecular forces of different nature. Тhe stability of the mixture and aminoformaldehyde esterified alkyd resin in butanol is generated largely by thermodynamic forces of molecular interaction; the degree of butanolate melamine-formaldehyde resin has the greatest effect on the stability of the system. Conducted research on the stability of the paint mixtures of various film-forming resins on the basis of the evaluation criteria can be used to improve the technology of protective and decorative wood finish.

Functional characterization and structural modelling of peptidoglycan degrading β-N-acetyl-glucosaminidase from a dental isolate of Serratia marcescens

2020 ◽  
Vol 23 ◽  
Author(s):  
Aditi Rathee ◽  
Anil Panwar ◽  
Seema Kumari ◽  
Sanjay Chhibber ◽  
Ashok Kumar
Keyword(s):  
Functional Characterization ◽  
Major Change ◽  
Crystal Form ◽  
Bound State ◽  
Dynamics Simulation ◽  
Gram Positive ◽  
Structural Cell ◽  
Stability Structure ◽  
Arginine Residues ◽  
The Stability

Introduction:: Enzymatic degradation of peptidoglycan, a structural cell wall component of Gram-positive bacteria, has attracted considerable attention being a specific target for many known antibiotics. Methods:: Peptidoglycan hydrolases are involved in bacterial lysis through peptidoglycan degradation. β-N-acetylglucosaminidase, a peptidoglycan hydrolase, acts on O-glycosidic bonds formed by N-acetylglucosamine and N-acetyl muramic acid residues of peptidoglycan. Aim of present study was to study the action of β-N-acetylglucosaminidase, on methicillin- resistant Staphylococcus aureus (MRSA) and other Gram-negative bacteria. Results:: We investigated its dynamic behaviour using molecular dynamics simulation and observed that serine and alanine residues are involved in catalytic reaction in addition to aspartic acid, histidine, lysine and arginine residues. When simulated in its bound state, the RMSD values were found lesser than crystal form in the time stamp of 1000 picoseconds revealing its stability. Structure remained stably folded over 1000 picoseconds without undergoing any major change further confirming the stability of complex. Conclusion:: It can be concluded that enzymes belonging to this category can serve as a tool in eradicating Gram-positive pathogens and associated infections.

scholarly journals Effects of Sources and Forms of Vitamin K3 on Its Storage Stability in Vitamin Premixes or Vitamin Trace Mineral Premixes

Animals ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 1140
Author(s):  
Huakai Wang ◽  
Pan Yang ◽  
Longxian Li ◽  
Nan Zhang ◽  
Yongxi Ma ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Storage Time ◽  
Storage Stability ◽  
Choline Chloride ◽  
Crystal Form ◽  
Negative Effects ◽  
Trace Mineral ◽  
Vitamin K3 ◽  
Choline Group ◽  
Micro Sphere

Six types of vitamin K3 (VK3); two sources (menadione sodium bisulfite, MSB; menadione nicotinamide bisulfite, MNB), and three different forms (crystal, micro-capsule, and micro-sphere) were used to determine the retention of VK3 in vitamin premixes (Experiment 1) or vitamin trace mineral (VTM) premixes (Experiment 2) after 1, 2, 3, and 6 months of storage. The retention of VK3 in vitamin premixes was evaluated at 25 °C/60% relative humidity or 40 °C/75% relative humidity in an incubator in Experiment 1 and in VTM premixes (choline chloride: 0 vs. 16,000 mg/kg) stored at room temperature in Experiment 2. The VK3 retention in vitamin premix or VTM premix decreased significantly with the extension of storage time (p < 0.05). In Experiment 1, the VK3 retention was higher in the 25 °C/60% incubator (56%) than in the 40 °C/75% incubator (28%). The MNB retention (52%) was higher than MSB retention (32%). The retention of VK3 in micro-capsules (43%) or micro-spheres (48%) was higher than the crystal form (35%) after six months of storage. In Experiment 2, there was no difference between the retention of MSB (49%) or MNB (47%). The retention of VK3 of micro-capsule (51%) or micro-sphere (54%) was higher than that of crystal form (40%). The VK3 retention was higher in the choline-free group (51%) than in the choline group (47%) after six months of storage. Finally, the predicted equations of VK3 retention with storage time in vitamin premixes or VTM premixes were established. The R2 of the prediction equations was ≥0.9005, indicating that time is an important factor in predicting VK3 retention. In conclusion, the higher temperature-relative humidity, choline had negative effects on VK3 retention during premix storage. MNB retention was higher than MSB during storage of vitamin premix. The encapsulated forms of VK3, micro-capsules and micro-spheres, could improve VK3 storage stability in vitamin premix and VTM premix.

Stability and mutual impact of perception of parental pressure and infants' social support – A study based on the difference between employment status and household income

2021 ◽  
pp. 002072092199705
Author(s):  
Yong Wang
Keyword(s):  
Household Income ◽  
Employment Status ◽  
Working Mothers ◽  
Social Research ◽  
Research Report ◽  
Parental Pressure ◽  
Income Levels ◽  
Significant Difference ◽  
The Difference ◽  
The Stability

The purpose of this study is to explore the stability and interaction between parental pressure and social research report, as well as the role of employment status and family income levels in this process. This study used a special study on Korean children (PSKC) 2–4 waves. Use t-test, correlation and autoregressive cross-delay modeling to analyze the data. The main findings of this study are: First, over time, parental pressure and mother’s social research report are consistent. Secondly, the pressure of motherhood and childcare has an obvious lagging effect on upbringing, and vice versa. Third, there is no significant difference between working mothers and non-working mothers in terms of the stability of working parents' pressure, social research report and social research report for children's pressure channels. However, parental pressure can only predict the social research report of working mothers. Fourth, there is no significant difference between the stability and interaction of these two structures in household income levels. In short, the results show that, over time, parental pressure is consistent with mother’s social research report. The results also show that there is a significant cross-lag effect between the mothers’ perceptions of mutual pressure analysis. In the process from parental pressure to social research report, I found the difference between working and non-working mothers. The advantage of this study is that the expected longitudinal design was adopted during infancy and the priority between the two structures can be considered. The results of this study can be used as a source of intervention plans to help parents withstand severe parenting pressure and lack of social research report.

scholarly journals Modeling and Analysis of BDS-2 and BDS-3 Combined Precise Time and Frequency Transfer Considering Stochastic Models of Inter-System Bias

2021 ◽  
Vol 13 (4) ◽  
pp. 793
Author(s):  
Guoqiang Jiao ◽  
Shuli Song ◽  
Qinming Chen ◽  
Chao Huang ◽  
Ke Su ◽  
...  
Keyword(s):  
Stochastic Models ◽  
Satellite System ◽  
Modeling And Analysis ◽  
System Bias ◽  
Frequency Transfer ◽  
Global Navigation ◽  
The Difference ◽  
The Stability ◽  
Global Navigation Satellite ◽  
Precise Time

BeiDou global navigation satellite system (BDS) began to provide positioning, navigation, and timing (PNT) services to global users officially on 31 July, 2020. BDS constellations consist of regional (BDS-2) and global navigation satellites (BDS-3). Due to the difference of modulations and characteristics for the BDS-2 and BDS-3 default civil service signals (B1I/B3I) and the increase of new signals (B1C/B2a) for BDS-3, a systemically bias exists in the receiver-end when receiving and processing BDS-2 and BDS-3 signals, which leads to the inter-system bias (ISB) between BDS-2 and BDS-3 on the receiver side. To fully utilize BDS, the BDS-2 and BDS-3 combined precise time and frequency transfer are investigated considering the effect of the ISB. Four kinds of ISB stochastic models are presented, which are ignoring ISB (ISBNO), estimating ISB as random constant (ISBCV), random walk process (ISBRW), and white noise process (ISBWN). The results demonstrate that the datum of receiver clock offsets can be unified and the ISB deduced datum confusion can be avoided by estimating the ISB. The ISBCV and ISBRW models are superior to ISBWN. For the BDS-2 and BDS-3 combined precise time and frequency transfer using ISBNO, ISBCV, ISBRW, and ISBWN, the stability of clock differences of old signals can be enhanced by 20.18%, 23.89%, 23.96%, and 11.46% over BDS-2-only, respectively. For new signals, the enhancements are −50.77%, 20.22%, 17.53%, and −3.69%, respectively. Moreover, ISBCV and ISBRW models have the better frequency transfer stability. Consequently, we recommended the optimal ISBCV or suboptimal ISBRW model for BDS-2 and BDS-3 combined precise time and frequency transfer when processing the old as well as the new signals.

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