Quality Characteristics of Soft Kernel Durum -- A New Cereal Crop

Authors: Morris, Craig; FUERST, E - Washington State University

Submitted to: Wheat Genetics International Symposium Proceedings
Publication Type: Proceedings
Publication Acceptance Date: 10/3/2014
Publication Date: 9/25/2015
Citation: Morris, C.F., Fuerst, E.P. 2015. Quality Characteristics of Soft Kernel Durum -- A New Cereal Crop. Wheat Genetics International Symposium Proceedings. Chapter 30: 275-278. doi: 10.1007/978-4-431-55675-6_30.

Interpretive Summary: This book chapter demonstrates the transfer of Puroindoline genes and Hardness locus from T. aestivum to T. turgidum subsp. durum. As a result, the processing and utilization of durum were dramatically altered. Research has shown that milling can be performed on “standard” wheat mills. As opposed to coarse semolina, a low starch damage, fine particle size flour can be produced. Flour quality for the first soft durum, ‘Soft Svevo’, appears to be intermediate between hard and soft hexaploid varieties. Further breeding, selection and testing will be needed to resolve end-use quality in greater detail. However, pilot-scale pasta trials have indicated excellent spaghetti quality of soft durum. A number of baked goods, traditionally made from hexaploid wheat flour, have been successfully made. Durums can also be freely crossed with wild emmer wheat, providing direct access to an enormous gene pool of disease resistance and stress tolerance traits. The creation of soft durum increases the potential for wheat production under marginal cropping conditions, while establishing a new wheat class with expanded and novel uses.

Technical Abstract: Production of crops is in part limited by consumer demand and utilization. In this regard, world production of durum wheat (Triticum turgidum subsp. durum is limited by its culinary uses. The leading constraint is its very hard kernels. Puroindolines, which act to soften the endosperm, are completely lacking in durum. Currently, durum grain is milled on highly specialized mills which produce as their primary objective coarse semolina. Morris and co-workers (2011) described the development of soft kernel durum wheat. The soft kernel trait (Hardness locus) was introgressed into Langdon via Ph1b, and crossed to the Italian durum cv. Svevo (producing ‘Soft Svevo’). Soft Svevo behaves much like a soft hexaploid wheat with somewhat lower break flour yield, higher water absorption, and smaller cookie diameter. Pilot scale spaghetti manufacture indicated that hydration levels could be reduced to 26-27% for soft durum, as opposed to about 32% for commercial semolina. Cooking trials indicated equal-or-better texture, cooking loss and tolerance. Soft Svevo flour performed well in in a range of baked goods. These studies demonstrate the stable transfer of the Puroindoline genes from T. aestivum to T. turgidum subsp. durum. As such, the processing and utilization of durum was dramatically altered. The creation of soft durum therefore increases the potential for wheat production under marginal cropping conditions, while establishing a new wheat class with expanded and novel uses.