Wrinkled peas starch

Pea starch granules are oval, sometimes fissured, with a diameter of 20-40 ym (13). Molecular and structural characteristics of the two main components of field pea starch—amylose and amylopectin—are important in determining functional properties (25,26). Smooth field pea starch concentrate contains 97.2% starch of which 30.3-37.8% is amylose (9,23,25-27), and wrinkled pea starch concentrate contains 94.8% starch, which is 64% amylose (26). The gelatinization temperature of smooth pea starch is between 64 to 69 C, and that of wrinkled pea starch is greater than 99 C to 115 C. Gelatinization temperature depends on maturity of field pea seed and amylose content (26,27). 

Fig. 3. (A) Wheat starch. (B) Wheat starch under polarized light. (C) Com starch. (D) Cora starch under polarized light. ( ) Potato starch. (P) Potato starch under polarized light. (G) Regal lily starch. (H) Navy bean starch. I) Rice starch. (J) Wrinkled pea starch. (K) Cassava starch. (L) Oat starch, lowing a large compound granule. Magnification x 235. All photographs kindly provided by Professor R. M. Sandstedt of the University of Nebraska.

Wrinkled - pea starches The starches of most legumes generally show somewhat enhanced amylose contents of >28-35% (- broad bean starch, - pea starches). Naturally occurring wrinkled pea (Pisum sativum, convar. medullae ALEF) contains starches with 50% amylose. Plant breeders intend to generate a wrinkled pea with up to 90% amylose. 

Syn. Smooth Pea Starch Wrinkled Pea Starch G. Erbsenstarken E amidons de pois... 

Colonna, R, Mercier, C. (1984). Macromolecular structure of wrinkled- and smooth-pea starch components. Carbohydrate Research, 126,233-247. 

Wrinkled pea has a reduced starch level 66-75% of that seen in the normal round seed. The amylose content is about 33% in the wild-type round form, but is 60—70% in the wrinkled pea seed. Edwards et measured several enzyme activities involved in starch metabolism at four different developmental stages of wrinkled pea and found that branching enzyme activity at its highest level was only 14% of that observed for... 

Fig. 2. Typical DSC curves for pea and maize starch. Water volume fractions (Vi) wrinkled pea (A), Vi = 0.35 smooth pea (B) Vi = 0.29 high amylose maize (C), Vi = 0.20 and normal maize (D), Vi = 0.55. Reprinted from Ref 72, copjrright 1985, with kind permission from Elsevier Science.

A. represents the lesser amount of the starch constituents in the - starch granules, about 15-35% in the normal starches from maize, wheat, potato, maniok and rice. Special varieties of plants exhibit enhanced contents of a. ->amylomaize starches (50-80%) and - wrinkled pea (50-78%) are the most promising carriers of high-amylose starch for industrial utilization. 

Plant breeding is expected to deliver more high-amylose species (amylomaize, wrinkled pea) with stable starch properties and high yields. This ap-... 

P. are starch granules that are deposited in the cotyledons of different pea species as reserve polysaccharide, together with oligosaccharides and proteins. Industrial or pilot-plant products, obtained by ->wet milling and raffination from either Pisum sativum convar. sativum L. (smooth pea) or Pisum sativum convar. medullae ALEE (wrinkled pea). The first one contains 47-54% starch, 5-7% oligosaccharides, 21-34% protein and fiber, the second contains 30-37% starch, 25-36% protein, oligosaccharides and fiber. 

Introduction of special properties by breeding and genetic engineering high-amylose starches from wrinkled pea and amylocom amylopectin starches from waxy com, waxy rice, waxy sorghum, potatoes. 

Bhattacharyya, M. K., Smith, A. M., Noel-Ellis, T. H., Hedley, C., and Martin, C. 1990. The wrinkled-seed character of pea described by Mendel is caused by a transposon-like insertion in a gene encoding starch-branching enzyme. Cell 60, 115-122. 

Smith, A. M. 1988. Major differences in isoforms of starch-branching enzyme between developing embryos of round and wrinkled-seeded peas (Pisum sativum L.). Planta 175,270-279. 

Smith, A. M., Neuhaus, H. E., and Stitt, M. 1990. The impact of decreased activity of starchbranching enzyme on photosynthetic starch synthesis in leaves of wrinkled-seeded peas. Planta. 181, 310-315. 

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