What is the molar mass of NaOH? If the equation is arranged correctly, the mass units g cancel out and leave moles as the unit. According to the periodic table, the atomic mass of nickel Ni is Therefore, we can divide Privacy Policy.
Skip to main content. Mass Relationships and Chemical Equations. Search for:. Key Takeaways Key Points The mole allows scientists to calculate the number of elementary entities usually atoms or molecules in a certain mass of a given substance. This can also be written as 6. Key Terms mole : The amount of substance of a system that contains as many elementary entities as there are atoms in 12 g of carbon Molar Mass of Compounds The molar mass of a particular substance is the mass of one mole of that substance.
Learning Objectives Calculate the molar mass of an element or compound. Key Takeaways Key Points The molar mass is the mass of a given chemical element or chemical compound g divided by the amount of substance mol.
Molar mass serves as a bridge between the mass of a material and the number of moles since it is not possible to measure the number of moles directly. Key Terms molar mass : The mass of a given substance chemical element or chemical compound in g divided by its amount of substance mol. Learning Objectives Convert between the mass and the number of moles, and the number of atoms, in a given sample of compound.
To convert between mass and number of moles, you can use the molar mass of the substance. Licenses and Attributions. Food hydrocolloids can contribute to this demand by versatile functions such as thickening, gelling, stabilising, and emulsifying, controlling texture and flavour release in food processing. Molar mass effects on viscosity and diffusion in liquid foods, and on mechanical and other physical properties of solid and semi-solid foods and films are overviewed.
In these functions, the molar mass is one of the key factors, and therefore, the effects of molar mass on various health problems related to noncommunicable diseases or symptoms such as cancer, hyperlipidemia, hyperglycemia, constipation, high blood pressure, knee pain, osteoporosis, cystic fibrosis and dysphagia are described.
Understanding these problems only from the viewpoint of molar mass is limited since other structural characteristics, conformation, branching, blockiness in copolymers such as pectin and alginate, degree of substitution as well as the position of the substituents are sometimes the determining factor rather than the molar mass. Nevertheless, comparison of different behaviours and functions in different polymers from the viewpoint of molar mass is expected to be useful to find a common characteristics, which may be helpful to understand the mechanism in other problems.
To contribute to the universal demand for secure and sustainable food supply, food colloids science and technology can do many things. It can create palatable foods from underutilized resources, and can reduce the food loss.
It is reported that there are many people who die from the insufficient supply of foods and malnutrition while food was wasted by improper distribution in some regions as pointed out by the World Health Organization WHO.
While the life expectancy in Japan is the longest in the world, it is demanded to extend the healthy life expectancy, which is defined as the period in which the person can enjoy life without any limitation in day-to-day activities resulting from health problems, because the increase of the life-style related diseases make some people ill, which lowers quality of life and causes a significant financial burden. Palatable, healthy, and sustainable foods are demanded.
From the nutritional standpoint it is possible to have a completely adequate diet in the form of fluid foods that require no mastication. However, few people are content to live on such a diet. Modern food and pharmaceutical companies sell manna-like foods, which proclaim to be palatable and healthy.
But, people don't eat them every day. Bourne raises the great number of dentists in the developed countries which supports his argument. Palatable and healthy foods are even more demanded in such a situation as in the age of covid because disadvantaged persons, such as refugees and patients, are under the harsh stresses. Small molecules such as resveratrol, bile acid, genipin, short fatty acids like butyric acid, have been reported to increase thermogenic activities in animal or cellular models Gao et al.
Nguo et al. They found that MIT was independent of the chain length. Therefore, the palatability plays a role not only in mental and spiritual domain, but also it is correlated with physiological function. Texture and flavour are key factors governing the palatability and molar mass effects on these factors are discussed in the present review.
People demand the diversity. A flexible manufacturing system which can manage to produce small quantity but various kinds is required in production of foods. This is a characteristic feature demanded for food industry different from other industries where most products can be exactly the same and produced massively at a lower price as much as possible although artificial intelligence AI technology may be able to make custom-made products for each individuals in the future.
Since foods generally consist of multiple components, and are changing comparatively rapidly in comparison with other industrial products made of hard materials such as metals, ceramics, and synthetic plastics, therefore the shelf-life is comparatively shorter. While super strong and unchangeable products are required in the other industry, food should be fragile in a sense that it should be chewable and digested by enzymes to be processed in oral and gastrointestinal organs.
It is well known that not only the molar mass but also the structural characteristics such as linkage mode of glucose in polysaccharides make the performance diversity even for similar molar mass compounds. Functional proteins have their specific molar mass because their role in the life phenomenon is designed naturally.
Therefore, it seems to be absurd to dare to write an overview on the effects of molar mass in food quality and health related properties. The authors tried to find some common characteristics or rules governing the mechanism which could be applied to other materials or phenomena within food and health problems.
As an intrinsic characteristic quantity of a matter, it should not depend on the gravity and should be the same on the earth and on the other planet.
However, many papers have been using the former term. In some communities, a concept of the molecular weight is used to represent the mass of the particle even if this particle is composed of different molecules. Starch is known to consist of different molecules, a linear molecule amylose and a branched molecule amylopectin, but many starch chemists use a term starch molecule or a term molecular weight of starch.
Although the detailed discussion of the definition of molar mass or molecular weight is not a main topic of this paper, it is important to clarify the definition of molar mass especially when the structure and properties of complex heterogeneous molecules extracted from natural resources are discussed.
Omission test can identify necessary taste ingredients to make an imitation food such as scallop, crab, sea urchin. However, the combination of these tastants in liquid does not give the pleasure or satisfaction for a man to actually chew a real food.
Successful examples are kanikama crab stick and ikura salmon roe where texture is reproduced. Omission tests were done by Watanabe, Lan, Yamaguchi, and Konosu They found eight taste-active components, glycine, alanine, glutamic acid, arginine, adenosine monophosphate, sodium, potassium, and chloride ions and stated that glycogen enhanced continuity, complexity, fullness, mildness and thickness.
Since glycogen is a highly branched polysaccharide, the molar mass is a determining factor of its thickening function. The necessity of inorganic ions to make imitation foods realistic is understood by the cross modal interaction of different sensations and psychophysical effects, which will be discussed in section 9 Molar mass effect on flavour intensity. The concept of koku was recently re-visited by Nishimura and Egusa and koku was defined as a phenomenon perceived when humans feel complexity, mouthfulness, long-lastingness with a good balance between taste, odor and tactile sensation.
A simple taste such as pure sweetness or bitterness was excluded from koku. Nishimura et al. They stated that it was exactly the same koku what was proposed by Japanese research groups. These papers described successfully the substances which are useful to design palatable foods, but it is necessary to add the viewpoint of the texture which contribute to especially the important factor of koku , the continuity and fullness.
This was already pointed out by a pioneering work of Watanabe et al. Molar mass problem is involved in physical and chemical aspects in designing koku or palatability. A systematic understanding of the kind of amino acids, their arrangement order, and their length as well as their effects on the viscosity is required for the design.
To make the taste research more practical, the texture should be taken into account, and also the role of salt should be understood from the viewpoint of taste-odor, or taste-taste interaction.
This will be discussed later in section 9 Molar mass effect on flavour intensity. Granular protein can prevent the shrinking and dripping of liquid, during frying, of hamburger steak consisting of minced meat with granular protein.
Not only the fibrous texture but also juiciness is an important texture characteristics to produce an authentic meat mouthfeel Puolanne, ; Warner, Low molar mass and high molar mass emulsifiers act differently on the surface of oil droplets. While low molar mass emulsifiers may adsorb faster on the surface of oil droplets because their diffusion coefficient is larger than that of high molar mass ones, high molar mass emulsifiers may show a steric stabilisation effect Dickinson, The steric repulsion is dependent not only on molar mass of the polymer forming layers surrounding droplets but also on the conformation and branching Dickinson, All the hydrocolloid scientists know the importance of molar mass, for example, to control the viscosity of fluid foods, high molar mass polysaccharides can increase the viscosity at a very low dose concentration if the conformation is not completely random coil.
Random coil polysaccharides such as pullulan and dextran are not effective to increase the viscosity. The solution viscosity of low molar mass saccharide is much lower than that of higher molar mass saccharide, i. Though there have been many papers studying food processing or health related problems by changing the dose concentration of different polysaccharides without controlling the molar mass, it is evident that it is not possible to compare the concentration dependence or the different effects of these polysaccharides when the molar mass of each polysaccharide is different.
In the industrial application of these thickening and gelling polysaccharides, the solubility and the hydration rate and extent are important, which are related to the molar mass and other structural characteristics.
In cellulose derivatives, the degree of substitution and its position and length are determining factor of the function. Although the conformation or the stiffness of polysaccharide chain plays important roles in their performance, it is worthwhile to pay attention to the molar mass effect.
The molar mass of some polysaccharides have not been determined with high precision because their structures are heterogeneous and difficult to purify to be subjected to molar mass determination.
Since fibrils of globular protein appeared, the concept of globular protein that forms a gel only at high concentrations changed drastically. McKim et al. This will be discussed later in 6. Here, the molar mass seems to be a key word to understand the safety issues. Heparin is a naturally occurring sulphated polysaccharide with MW ranging from 5 to 40 kDa belonging to the family of glycosaminoglycan.
Since forty years ago, low molecular weight heparin LMWH prepared by chemical or enzymatic hydrolysis or ultrasonic degradation has attracted more attention because of its stronger activity. In the nutrition science, it was believed that proteins are hydrolysed into amino acids to be absorbed at intestinal walls. Ejima, Nakamura, Suzuki, and Sato and Ejima, Yamada, and Sato reported, however, that di- or tri-peptides were detected in human plasma after ingestion of maize and wheat gluten hydrolysates, and aspartic dipeptides in rat plasma after administration of liver protein hydrolysates.
The same research group led by Sato detected di-peptide in human plasma after ingestion of collagen or elastin hydrolysates. They emphasize the importance of detecting bioactive compounds such as dipeptides in the body because it can be related with the biological response upon ingestion of the protein hydrolysate.
A similar situation is developing in the other part of the body. Synovial fluids play a key role for the smooth movement of joints of knee or any other part conferring the lubrication as well as shock absorption. Hyaluronan also called hyaluronic acid, HA is a main ingredient, also occurring in connective, epithelial, and neural tissues e. HA a copolymer consisting of glucuronic acid and N-acetyl-glucosamine, and occurring naturally, but is also produced by microbial fermentation.
Physiological functions of HA have been found strongly influenced by molecular weight MW and some examples are discussed in section 6. Recently, the topical cream on the knee was proposed, and oral therapy, i.
In a traditional nutrition science, it is believed that all the nutrients are digested into monomers and absorbed in the intestine. Oe et al. In all therapies, injection, topical, oral ingestion, the molar mass is recognized as an important factor. Electroporation method as a transdermal drug delivery which allows the penetration of higher molar mass drugs has been attracting attention Kawai et al.
Molar mass of a hydrocolloid molecule increases when it is reconstructed or synthesized while it decreases when it is degrade or digested. Since food is a complex material consisting of many ingredients, and the human body also consists of various parts and is a complex system in which each part interact each other. In each specific problem, the degradation and reconstruction of molecules are governed by specific enzymes and thus different problems cannot be compared directly each other, but methods of study are sometimes similar thus a study on one problem can learn from another study, and finally the total aspects should be overviewed to solve each specific problem.
The viscosity of the liquid foods is in most cases determined by food macromolecules and the molar mass is the determining factor together with the structural characteristics, conformation, molecular shape, stiffness, and degree of branching. Some problems of the mixture of high molar mass and low molar mass polymers, which have an important practical significance in medical problems such as hyaluronate related with knee pain in 6.
The elasticity of solid or semi-solid, gel-like foods is also dependent on molar mass and also the structure of junction zones, the network density and the elastically active network chains, which are also dependent on molar mass. Electric charges, ionic strength and pH are also important factors, and therefore the effect of molar mass is not isolated from these factors. Nevertheless, it is expected that extraction of common features in various phenomena which are strongly influenced by the molar mass of polymers which play an important role is useful.
From this overview, unresolved problem may find a clue from the other problems. Although it is difficult to find a general rule to understand the role of molar mass in food characteristics and disease therapy, effects of molar mass on structural formation and breakdown in food and health are overviewed in the present paper. There are many methods to obtain or analyse polysaccharides and proteins with different molar masses Table 1.
Each methods have advantages and disadvantages. For example, oligomers of sulphated polysaccharides have been attracted much attention because of their biological activities, and depolymerised by ultrasonication, gamma-irradiation, acid or enzymatic hydrolysis. In another report, the sulphate content of fucoidan slightly increased by ultrasonic degradation Guo et al.
Some methods of molar mass change, decrease or increase, applied to polysaccharides and proteins in food and health industries are shown in Table 1. The intrinsic viscosity also called limiting viscosity number is often determined by an Ubbelohde type capillary viscometer. The intrinsic viscosity has a unit of the inverse of the concentration, and represents the volume the polymer occupies in the solution.
Therefore stiff chains or an expanded chain molecules show a high intrinsic viscosity value while compact or less expanded molecules show a lower value. The relation between the intrinsic viscosity and molar mass of polymers, called Mark-Houwink-Sakurada MHS equation, is written as. The MHS exponent a is reported as 0.
Solution properties of pullulan was extensively studied Kawahara et al. The MHS exponent of guar gum was reported as 0.
The intrinsic viscosity has units of reciprocal concentration, so the product with concentration is dimensionless. Since the viscosity of polymer solutions is generally dependent on shear rate, the viscosity obtained by the extrapolation to zero shear rate is used to understand the concentration dependence systematically. The slope above the critical concentration was found about 3. The deviation of the behaviour for galactomannans guar gum and locust bean gum may be due to specific attractive interactions between side groups on the polymer chains or the stiffness of polymer chains.
It should be reminded that a typical behaviour shown in Fig. Cellulose derivatives are soluble and have been studied extensively. A similar shear rate dependence of the steady shear viscosity for beta glucans from oat, barley, wheat flour and wheat bran is shown in Fig. Another example is shown for galactomannan solutions in Fig. Rodriguez-Canto et al. The following features are noted: 1 the viscosity at lower shear rates increases with increasing molar mass; 2 the viscosity decreases with increasing shear rate, which is called shear thinning; 3 The viscosity of the solution of the lowest molar mass does not depend so much on the shear rate, and shows approximately a constant value at lower shear rates.
This is called a Newtonian plateau. Because of the limited sensitivity of the rheometer, the viscosity at very low shear rates cannot often be measured. It should be noted that some published papers erroneously showed a steep rise of the viscosity at lower shear rate with decreasing shear rate, which were probably caused by neglecting the low sensitivity limit of the sensor. Diffusion is a ubiquitous phenomenon of motion of molecules or particles in any phase gas, liquid, or solid caused by the concentration gradient.
This is caused not by an external force but by spontaneous collision in Brownian movement Doi, ; Tanaka, The diffusion is described by a Fick's equation. This can be generalized to three dimension. Rate of diffusion of aroma compounds in a gas phase, carbon dioxide diffusion into egg white through the pore of shell during storage, that of seasonings such as salts, acid, and of sugars in pickling and salting as well as release of tastants in oral cavity, and release of nutrients and drugs in gastrointestinal tract, plasticizers motion in packaging films, and many others, …all play important roles in food and health.
This equation is valid only for an infinitely dilute solution, and for a particle which is larger than the solvent molecule. When a rigid rod molecule rotates, it can sweep a large volume with low density and thus its d f is 1 much smaller than d f of a sphere Burchard, Diffusion coefficient of biomolecules has been measured by ultracentrifugation, dynamic light scattering DLS , nuclear magnetic resonance NMR , and fluorescence correlation spectroscopy FCS.
The value close to 0. Pullulan has been studied extensively as a water soluble, model random coil polysaccharide. The diffusion coefficient of pullulan as a function of molar mass is shown in Fig. The exponent 0. Double-logarithmic plot of D for cycloamylose in 0. They determined the MW and diffusion coefficient D for cycloamylose samples from sedimentation equilibrium in dimethylsulphoxide and by dynamic light scattering in 0.
Dependence of D on MW is shown in Fig. They noticed, taking into account that correction is made for the effect of fluctuating hydrodynamic interaction, that measured translational diffusion coefficients in the aqueous NaOH agreed fairly well with Monte Carlo data and also with the prediction from the Yamakawa—Fujii theory for the associated Kratky-Porod ring combined with relevant theoretical expressions for the expansion factors Nakata et al.
The Stokes-Einstein equation is valid only for infinitely dilute solution. For finite concentration, a corresponding relation. Diffusion coefficient of pullulan was found to decrease with increasing concentration for lower MW 5. This dependence can be generalized by scaling as shown in Fig. The asymptote with zero slope is shown by black dashed line. All curves are normalized by the procedure that merely leads to the shift of the concentration dependence along the horizontal and vertical axes Nesmelova et al.
For interpretation of the references to colour in this figure legend, the reader is referred to the Web version of this article. Diffusion coefficient of probe molecules introduced in gelling polymers was used to estimate the mesh size of gel networks. The decrease of solute gellan concentration at T I 0 might cause a decrease in the local viscosity because solubilized random coil gellan molecules were incorporated into helices and their aggregates.
The increase of D gel at T I 0 was more pronounced than expected from the decrease of local viscosity. Therefore, it is considered that the MW distribution of the gellan remaining as a random coil as a solute among the network of aggregates was shifted to lower MW values because higher molar mass gellan chains were preferentially incorporated to junction zones than lower MW chains. This behaviour probably reflects the collapse of the solute gellan chain, which is caused by effective shielding high salt concentration of repulsion between negative charges on the carboxylate ions Ogawa et al.
Temperature dependence of the NMR echo signal intensity at 1. Closed circles, cooling; open circles, heating. Data points inside brackets indicate D values that are overestimated by convection. The solid straight lines indicate D pul in dilute solution. The diffusion coefficient of pullulan decreased with decreasing temperature, and it was concluded that pullulan chains were not involved directly in the aggregation of gellan, and remained dissolved during the gelling process, probably due to the high solubility of pullulan in water.
The diffusion of pullulan is thought to be restricted by the hydrodynamic interaction with the solute gellan as well as the network of aggregates. The restriction became smaller with decreasing solute gellan concentration and increasing network pore size, both of which result from the thickening of the aggregates. The change in the microscopic surroundings of pullulan during the cooling process is shown schematically in Fig.
A schematic representation of the microscopic environment of pullulan above a , at b and below c T I 0 Shimizu et al. When a physical polymer gel is immersed in a solvent, molecular chains which are not connected to the junction zones were found to release out from the gel to the solvent Djabourov et al.
It has been observed that the immersion of potassium type deacylated gellan gels in water or electrolyte solution induces chain release, and this release is more noticeable for shorter chains. Ultimately the gel becomes eroded and then disintegrates, and the rate of collapse depends on polymer concentration, original molecular mass and the initial salt content of the gels and the solvent. Salt diffusion from the gels into the solution is faster than chain release; chains which lose condensed or bound ions cannot retain a helical conformation, and so they diffuse out into the solution.
Funami et al. They estimated the diffusion coefficient 1. This is reasonable since molecular chains released out from the gel network were shorter than un-released chains. These authors also found the chain release as mass loss up to days. They ascribed this difference to the retardation of the mobility of gellan molecules in gel network. Molar mass is a key for the gel formation. When the material changes from sol state to gel state, the molecules are connected each other spanning the whole space in the vessel, and this is called the percolation at which the molar mass is thought to diverge to infinity De Gennes, ; Nishinari, ; Tanaka, ; Tokita, Gelling polysaccharides and proteins have been used widely for controlling the food texture.
Though it may have some merit, it does not distinguish two concave and convex curves connecting the origin and the break point in the force-deformation plot. We hope that these distinction will be taken into account in the near future. The average number of residues per helical turn for other protein helices is also determined as 3.
While the helix structure is studied extensively in proteins, that is not so much studied in polysaccharides. The helix formation is the prerequisite for gel formation for agarose, gellan, carrageenan double helices , schizophyllan triple helices , however the minimum molar mass required to form a double helix or triple helix has not been so much studied because of the difficulty to get samples. For gellan, Ogawa et al. It was thought that the chain length was too short to form double helices.
This assertion is corroborated by DSC thermograms which ceased to show exothermic peaks Fig. Temperature dependence of intrinsic viscosity for Na-gellan aqueous solutions with 25 mmol NaCl.
No peak was observed for G6. Ogawa et al. Bowman et al. The plateau value increased with increasing molar mass within the DP range from to however the highest molar mass DP still continued to increase even after 10, min Clark et al. Lazaridou et al. Gelation process of these OGL solutions is shown in Fig. The highest molar masse sample MW kDa did not show any tendency to gel, i. In amylose gelation, the plateau value increased with increasing molar mass as shown in Fig.
The apparent inconsistency between Fig. As shown in Fig. This reminds us the slow gelation rate of gelatin solutions. The storage modulus of 1. It is also necessary to take into account the molar mass range and in addition molecular conformation, flexible or stiff, when the modulus of different gelling polymers are compared as a function of molar mass.
It should be noted that there is a critical molar mass and a critical concentration below which no gelation occurs. Since it is difficult to prepare samples with different molecular weight and with a narrow molecular weight distribution, there have not been so many studies on the molecular weight dependence of elastic modulus of gels.
Shear modulus of alginate gels as a function of weight average degree of polymerisation was reported to show two regions; the initial steep ascending region and then levelled off and show a long horizontal region. This comparison is difficult because it is difficult to obtain the series of samples with the same molar mass and only different in the guluronic acid residue content. These tendencies can be summarised as shown in Fig. The elastic modulus increases steeply with increasing molar mass, and then it levels off above a certain molar mass.
The temperature dependence of the elastic modulus has been attracting much attention. Whether the elasticity of agarose is entropic or energetic has been debated for a decade just after the 2nd world war in Japan Nishinari, a. This temperature T max shifted to higher temperatures with increasing molar mass and concentration Fig.
It was found that the entropic part decreased while the energetic part increased with increasing temperature. Strain-Stress curves of 2.
Stress values were taken after 2 min strain Watase; Nishinari, It was shown that box type spectra extended to longer relaxation times with increasing molar mass at a constant concentration, and that both breaking stress and breaking strain increased with increasing molar mass Fig.
More recently, Moritaka. As expected, the size of masticated fragments decreased with decreasing molar mass of agarose, which forms more brittle gels broken at lower fracture strains. Fang et al. The results revealed three distinct and successive steps in the binding of calcium to alginate with increased concentration of Ca ions.
The formation of egg-box dimers and their subsequent association are thermodynamically equivalent processes and can be fitted by a model of independent binding sites. In addition, the step iii showed different association modes depending on the molar mass of alginate.
Gelation kinetics and equilibrium gel properties of alginate aqueous solutions induced by in-situ release of Ca ions from Ca-EDTA during D-glucono-delta-lactone GDL hydrolysis were observed and the modulatory effects of GB were analysed quantitatively. It manifests an inhibitory effect exerted by the addition of GB. Moreover, the gelation kinetics seems not to be altered significantly by the addition of GB. The red zigzag lines represent oligomer GB. Zhang et al. The addition of GB shows an inhibitory effect in the range of 0.
Mixed egg-box dimers between ALG and GB were ruled out because of cooperativity requirement of dimerisation. The promotive effect in the higher Ca concentration regime was assigned to the role of GB dimers participating in and enhancing the lateral aggregation of ALG dimers.
Inhibitory effect is attributed to the binding of calcium ions to shorter guluronate chains. Those findings may be useful in food processing and also have some therapeutical significance in the rheology of sputum as discussed in the following section. More recently, Zhang, Hu, et al. This is significantly different from the case of alginate where no gelation could be induced at all.
In the range of 0. Polysaccharides are frequently used to reduce the fat content, and to improve the texture and water holding capacity WHC of protein gels. They found that WHC increased simultaneously with turbidity and thermal stability, accompanied with the decrease in surface hydrophobicity with increasing molar mass of added SA.
They noticed that the addition of sodium alginate shifted the thermal transition temperature to higher temperatures detected by DSC with the higher contribution by a higher molar mass SA, which is consistent with the same stabilisation by the addition of flaxseed gum to salt-soluble meat protein, but is contradictory with the reported thermal destabilisation of myofibrillar, sarcoplasmic and connective tissue protein by the addition of SA.
They observed that inhomogeneity of cavities formed in SA-protein gel network was enhanced by the higher molar mass SA, which resulted in the increase in WHC because they thought that large cavities could store more water. Compressive stress increased with increasing molar mass which is in good agreement with Fig. Their interpretation was as follows: the molecular size has a significant impact on the viscosity of polymer solutions, thus influencing the diffusion rates of the interacting polysaccharide chains.
However, it is difficult to understand this explanation because the stress-strain curves shown in Fig. Unfortunately, gels from 65 kDa were so weak to keep the shape to do the compression measurements. The inconsistency between the Young's modulus from the slope of stress-strain curves in Fig.
Heat set gel formation also depends on molar mass. This rheological tendency is in accordance with DSC observation in which an endothermic peak appeared on heating accompanying the gelation. More detailed studies on the gelation of MC changing molar masses at a constant degree of substitution, preferably using regioselective substitution, are expected in the future.
The gelation of KGM occurs through the alkali-induced removal of acetyl groups which confer the solubility for this polysaccharide Nishinari, b. KGM forms a thermally stable gel by deacetylation upon addition of alkaline coagulant and the gelation of KGM is promoted by heating, in contrast to many other cold-set thermo-reversible gels.
This is consistent with the general tendency observed in gelatin, carrageenan, alginate and agarose gels as described above. To understand the effect of molar mass on the gelation, it is necessary to obtain KGM sample with a constant degree of acetylation DA with different molar masses, but this has not yet been done because of the difficulty of sample preparation.
The more detailed knowledge will improve further the products. Crystallinity of solid fat is generally much higher than high molar mass polysaccharides and proteins, and the linear elastic range is much narrower than in semi-solid foods mainly composed of polysaccharides and proteins. Spreadability of semi-crystalline solid fat such as butter and margarine is an important functionality during consumption, and this characteristics is different from high molar mass polysaccharide and protein food gels.
Ethyl cellulose EC has been used as oil structuring materials. Gravelle, Barbut, Quinton, and Marangoni examined the oleogel composed of canola oil or soybean oil in the presence of EC with or without surfactants. As is shown in Fig.
From the cryo-SEM observation of partially de-oiled gels, it was found that the internal structure consisted of oil droplets entrapped within a network of interconnected strands or bundles of EC, which formed a scaffolding to support the gel Zetzl et al. Therefore, Gravelle et al. The finding that the gel strength increased with increasing molar mass of EC was also found for EC oleogels of other vegetable oils, canola, soybean, and flaxseed oil Zetzl et al.
Replacing trans and saturated fatty acids in margarines or shortenings has been pursued by bakery industry to produce pastries, croissants, and danishes. Blake and Marangoni examined the effect of composition of a fat substitute for pastries on rheological properties. This fat substitute is called rolled-in shortenings which are folded into dough to form thin laminated layers between dough layers. If two equal amounts of moles of different substances take up different volumes, then it indicates that the molecules of the substance with the larger volume are larger than the molecules of the substance with the smaller volume.
Molar mass is also used to determine what percentage any given element in a compound contributes to the total mass of the compound. For example, consider a sample of Because you know that the molar mass of carbon is Molar masses of atoms can also be used to figure out the precise molar masses of complex molecules without experimenting on them directly. By adding the molar mass for each atom that makes up the molecule, you discover what the molar mass of the molecule as a whole is.
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He started working with Mechanical Turk and then started contracting with individuals and companies directly via the Web. How to Convert Moles to Millimoles. Density to Molarity Conversion. How to Convert Moles to Molecules.
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