Proteins in starches

Based on these results, several different commercial and experimental protease samples were obtained from enzyme companies and were tested for starch yield using the enzymatic corn wet milling process (Figure 3). Two commercial protease enzymes (enzymes A and C) gave starch yields comparable to the conventionally wet milled sample. Pasting properties, residual protein in starch, and surface characteristics of starch samples obtained from... 

Spheres. Semilogarithmic plots of the electrophoretic mobility, p ( velocity/voltage gradient), as a function of gel concentration have been found to be linear for monoraolecular proteins in starch... 

Potassium is required for enzyme activity in a few special cases, the most widely studied example of which is the enzyme pymvate kinase. In plants it is required for protein and starch synthesis. Potassium is also involved in water and nutrient transport within and into the plant, and has a role in photosynthesis. Although sodium and potassium are similar in their inorganic chemical behavior, these ions are different in their physiological activities. In fact, their functions are often mutually antagonistic. For example, increases both the respiration rate in muscle tissue and the rate of protein synthesis, whereas inhibits both processes (42). 

The basic raw materials for the production of beer are sweet worts formed by en2ymatic hydrolysis of cereal starches. The principal cereal is barley which, after malting, is also the source of en2ymes that hydroly2e starches, glucans, and proteins. In some countries, eg, Germany, the mash biH consists... 

Infusion Method. Infusion is a classic method for top-fermented beers and is used for ad British types. The whole mash is heated graduady from mashing-in to mashing-off with holding times for the degradation of protein and starch. No part of the mash is boiled and the malt, therefore, must be well-modified to assure the breakdown of ad soluble substances. Because no boiling takes place there is no physical breakdown of the malt, and consequentiy infusion is not as effective as decoction despite the better protection of the enzymes. 

In addition to plastics materials, many fibres, surface coatings and rubbers are also basically high polymers, whilst in nature itself there is an abundance of polymeric material. Proteins, cellulose, starch, lignin and natural rubber are high polymers. The detailed structures of these materials are complex and highly sophisticated in comparison the synthetic polymers produced by man are crude in the quality of their molecular architecture. 

Polyols are present in desiccation tolerant lichens and liverworts, although not in mosses (Lewis, 1984). More generally starch hydrolysis and sugar accumulation occur in many plants experiencing severe water deficits (Hsiao, 1973). It is tempting to speculate that the accumulation of low molecular weight solutes in reponse to water stress represents a mechanism for the protection of membranes and proteins in the dry state. 

The yield and the composition of the fractions from soy bean meal obtmned with isolating WUS is shown in Table 1. The removal of cold water solubles, proteins and starch from soy meal was successful. The larger part of the material appeared in CWS, 59.1%. UFF contained mainly oligosaccharides and some water soluble proteins and UFR contained mainly water soluble proteins. The solution of SDSS and DTT extracted the residual proteins from the soy meal and the extract consisted for over 80% of proteins. Since the yield of the HWS fraction is only 0.4%, the composition is not discussed here. The remaining WUS contained 90% of NSP and the yield was 15.7%, which indicates that from the polysaccharides present in soy meal 92% was recovered in the WUS. By isolating WUS a fraction is obtained in which almost all cell wall polysaccharides are recovered and which contained only little other components. 

Whey may be substituted for starch by as much as 25% in extruded corn snacks, but the product does not puff as much as com alone, as the water-holding whey protein does not react with the starch matrix (Onwulata et al., 1998). WPCs or isolates can be added along with starch to create expanded snack foods with boosted nutritional content however, without texturization, whey proteins in amounts larger than 15% may interfere with expansion, making the products less crunchy. To counter this effect, whey proteins can be texturized with starch to improve their interaction with other food components in a formulation, principally to increase extmdate expansion. In one successful application, between 25% and 35% of the flour was replaced with whey protein (Onwulata et al., 2001a,b). 

In addition to the bio degradability of PHAs, they have another important feature, which is their hydrophobicity. This makes PHAs superior to their biodegradable competitors like starch and proteins in moisture resistance, despite the higher price of PHAs [18]. Apart from the unique combination of biodegradability and hydrophobicity, PHAs have other interesting and useful material characteristics. The combination of the various special material properties should be kept in mind for application development. 

Rye Proteins. While rye is the only European cereal able to completely replace wheat in bread, rye protein is not as effective as wheat protein. One reason for this is that as much as 80% of the protein in a rye sour dough is soluble compared with 10% of soluble protein in a wheat dough. One factor that inhibits the formation of a gluten-like complex is the 4-7% of pentosans present, which bind water and raise the viscosity of the dough. The crumb structure is then formed from the pentosans in combination with the starch. 

The preference for low protein, low starch damage flour in biscuits is obvious when the role of protein and damaged starch as water binders is considered. The aim in making biscuits is to produce a low moisture food. Incorporating components that bind water makes that aim more difficult. Table 2 considers the relative properties of biscuit and bread flours. 

Used in metal treating/cleaning operations, petroleum well activation, refining ore in the production of tin and tantalum, hydrolyzing of starch and proteins in production of various foods, in the production synthetic rubber, vinyl chloride and alkyl chlorides and in the manufacture of fertilizers, dyes and dyestuffs, artificial silk and pigments for paints. 

Smithies, O., Zone electrophoresis in starch gels group variations in the serum proteins of normal human adults. Biochem. J. 61, 629 (1955). 

Based on sequence similarity, it appears that transporters of this type may also assist in the uptake and acquisition of solutes unrelated to iron chelating compounds and vitamin Bi2 [68], Examples of prospective candidates are outer membrane proteins that are involved in sulfate ester utilisation in Pseudomonas putida [69], or polypeptides playing a role in starch binding at the surface of Bacteriodes thetaiotaomicron [70]. 

In agriculture and food, NIR has been a powerful tool for decades. All shipments of grain leaving US ports are analyzed for moisture, fat, protein, and starch via NIR. Processed foods are also a prime venue for NIR percent of fat in cheese spread, hardness of wheat, and freshness of meats are just some of the applications in food. 

The composition of protein and starch fractions produced from pin milling and air classification are related to a number of variables variability in composition of field pea cultivars, number of passes through pin mill and air classifier, vane settings and protein content of peas, and seed moisture (5,9,23,31). 

Protein content of field peas is negatively correlated with lipid, cell wall material (CWM), sugar, and ash content and positively correlated with starch separation efficiency and protein separation efficiency in air classification of pea flour. The lower separation efficiency of low protein peas may be due to their high lipid and CWM content which makes disintegration of seeds and separation into protein and starch particles by pin milling difficult. It is suggested that peas with a specific protein content should be used in order to control the protein and starch fraction contents (18). 

As seed moisture in field peas decreases, there is a decrease in starch fraction yield, protein content of starch fraction, protein content of protein fraction, and percent starch separation efficiency, and a concurrent increase in protein fraction yield, percent starch in starch fraction, percent starch in protein fraction, percent protein separation efficiency, and percent neutral detergent fiber in the protein fraction. Lower moisture content of field peas improves milling efficiency and results in more complete separation of protein and starch fractions, which could explain the increase in protein fraction yield and percent starch in starch fraction, improved protein separation efficiency and less protein in the starch fraction. The decrease in starch separation efficiency was probably due to the increased starch content of protein fraction and increased protein fraction yield with lower seed moisture. 

Field Pea Flour in Other Baked Products. When McWatters (44) substituted 8% field pea flour and 4.6% field pea concentrate for milk protein (6%) in baking powder biscuits, sensory attributes, crumb color, and density of the resulting biscuits were adversely affected. No modifications were made in recipe formulation when pea products were incorporated. The doughs were slightly less sticky than control biscuits that contained whole milk. This might be due to lack of lactose or to the different water absorption properties of pea protein or starch. Panelists described the aroma and flavor of these biscuits as harsh, beany and strong. Steam heating the field pea flour improved the sensory evaluation scores, but they were never equivalent to those for the controls. 

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