Peanuts isolates

Arachidonic acid gets its name from arachidic acid the saturated C20 fatty acid isolated from peanut (Arachts hypogaea) oil... 

Vegetable proteins other than that from soy have potential appHcability in food products. Functional characteristics of vegetable protein products are important factors in determining their uses in food products. Concentrates or isolates of proteins from cotton (qv) seed (116), peanuts (117), rape seed (canola) (118,119), sunflower (120), safflower (121), oats (122), lupin (123), okra (124), and com germ (125,126) have been evaluated for functional characteristics, and for utility in protein components of baked products (127), meat products (128), and milk-type beverages (129) (see Dairy substitutes). 

Negative relationships have now been found for plants in isolated pots in wheat (Farquhar Richards, 1984), peanut (Hubick, Farquhar Shorter, 1986 Hubick, Shorter Farquhar, 1988 Wright, Hubick Farquhar, 1988), barley (Hubick Farquhar, 1989 K.T. Hubick, S. von Caemmerer... 

Defatted flours are especially attractive as protein sources, since 10-12% substitution of wheat flour with 50% protein flour will raise total protein content of typical wheat breads by approximately 50%, and 25% substitution will almost double the protein content of cookies. Preparation of protein-enriched breads has been reported in the literature using soy flours and protein concentrates (25), peanut flours and peanut protein concentrates C26, 27), glandless cottonseed flours, concentrates and isolates (28), sunflower seed flours and seed protein concentrates (27) and sesame flours and protein concentrates (26). 

Considerable interest has been shown in uses of vegetable food proteins in cheese-type products. Attempts have been made to coprecipitate casein and vegetable protein in the typical vat process for making cheeses (35). Rhee (36) has found that up to 50% peanut protein isolate and 25% soybean isolate can be effectively substituted for sodium caseinate in the preparation of imitation cheeses. 

Peanut Protein Isolation, Composition, and Properties Jett C. Arthur, Jr. 

C]PCNB metabolism was studied in vivo with 30-day-old peanut plants grown in nutrient solution that contained 17.6 ppm [I CjPCNB. Plant tissue was extracted with cold 80t methanol 48 hr after final exposure to PCNB. The extracts were made aqueous and partitioned against chloroform at pH 5.5 and against ethyl ether at pH 2. Water-soluble, chloroform-soluble, and ether-soluble metabolites were isolated by various chromatographic methods and identified by mass spectrometry and/or by synthesis. The details of these studies have been published previously (, X ... 

Figure 6. Ether-soluble metabolites isolated from the roots of peanut plants treated with FCNB. This represents 13.7% of the C isolated from the roots.

Insoluble residue accounted for only 2% of the applied in peanut cell cultures harvested 14 days after treatment with, [) C]PCNB however, insoluble residue accounted for 37X of the isolated from the roots of peanut plants 33 days after treatment. When peanut cell cultures were treated with... 

Methylene chloride-soluble residues. Methylene chloride-or chloroform-soluble C-labeled products were major residues in all of the plant tissues examined except peanut cell ciiltures (Figure 3). Chloroform-soluble C accounted for 59.2 of the radioactivity isolated from peanut roots 48 hr after treatment with [ C]PCNB. The radioactivity was in the form of PCNB (28.7 ), pentachloroaniline (22.5 ), pentachlorothiophenol (2.6 ) pentachlorothloanlsole (3.1 ) pentachlorothloanlsole sulfoxide (0.5 ) S-(pentachlorophenyl)-2-thioaoetic acid [(S-(PCP)ThioAcetate] (0.5 ) and S-(pentachlorophenyl)-3-thio-2-hydroxypropionic acid [S-(PCP)ThioLactate] (0.2 ) and S-(PCP)Cys (trace) (J), The structures of these compounds are shown in Figure 13. Based on TLC, the last three compounds in this list were classified as polar chloroform- or methylene chloride-soluble residues and the remaining compounds were classified as nonpolar residues. 

Figure 13. Structures of chloroform-soluble residues isolated from peanut roots treated with [ C] PCNB. Chloroform-soluble accounted for 59.2% of the in peanut roots.

Figure 14. Methylene chloride- or chloroform-soluble residues were isolated from plant tissues treated with V C] PCNB. All tissues were treated for 3 days except lake water which is rich in blue green algae (9 h), peanut plants (2-day treatment/2-day post-treatment), and peanut cell cultures (1 day).

Wang and Kinsella (19) studied the fat absorption, and other properties of alfalfa leaf protein (ALP) concentrate and used the soy protein concentrate and isolate Promosoy-lOO and Promine-D,respectively, as the references. The fat absorption values are reported in ml oil/g sample. Converting these to percent fat absorbed (based on the specific gravity of peanut oil) results in values that are higher than those reported by Lin et al. (17) this was most evident in the case of the isolate. 

Peanut Seed. Ramanatham et al. (21) studied the influence of such variables as protein concentration, particle size, speed of mixing, pH, and presence of sodium chloride on emulsification properties of peanut flour (50% protein) and peanut protein isolate (90% protein). Emulsions were prepared by the blender... 

Data in Figure 6 show the effect of varying the pH and sodium chloride concentration on emulsion capacity of peanut protein isolate. Shifting the pH to levels above or below the isoelectric point improved emulsion capacity of peanut protein isolate in O.IM or 0.2M NaCl. Similar trends were noted when distilled water was used as the continuous phase (data not.shown). At the 0.5M NaCl concentration, however, little difference was noted in emulsion capacity at pH 3, 4, or 5 appreciable increases occurred when the pH was raised to 6 and above. At the highest salt concentration (1.OM NaCl), a gradual increase in emulsion capacity occurred when the pH was increased from 3 to 10. An overall suppression in emulsion capacity occurred as salt concentration increased except at pH 5 and 6. These emulsion-capacity curves closely resemble the protein-solubility curves of peanut protein shown in Figure 7... 

Figure 6. Effect of sodium chloride at different concentrations on emulsification capacity of peanut protein isolate at various pHs (21)...

Fontaine et al. (31) presented data comparing the solubility behavior of proteins of peanut and cottonseed meals, proteins of corresponding dialyzed meals, and isolated proteins. While the shapes of the pH/solubility curves for cottonseed and peanut meals differed, the response of proteins to the removal of dialyzable meal constituents was similar. Data indicated the presence of natural materials in both meals which decreased the solubility of meal nitrogen at certain acid pH values but exerted no effect at alkaline pH values. Thus procedures for solubilizing proteins by treatment with proteolytic enzymes should also be designed with consideration of the influence of non-protein constituents. 

Fischer, J., Klein P.-J., Farrar, G. H., Hanisch, F.-G. and Uhlenbruck, G. 1984. Isolation and chemical and immunological characterization of the peanut-lectin-binding glycoprotein from human milk-fat-globule membranes. Biochem. J. 224, 581-589. 

T Urano, MW Trucksess, SW Page. Automated affinity liquid chromatography system for on-line isolation, separation, and quantification of aflatoxins in methanol-water extracts of corn or peanuts. J Agric Food Chem 41 1982-1985,1993. 

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