Wheat Seed Proteins: Factors Influencing Their Content, Composition, and Technological Properties, and Strategies to Reduce Adverse Reactions

Abstract

Wheat is the primary source of nutrition for many, especially those living in developing countries, and wheat proteins are among the most widely consumed dietary proteins in the world. However, concerns about disorders related to the consumption of wheat and/or wheat gluten proteins have increased sharply in the last 20 years. This review focuses on wheat gluten proteins and amylase trypsin inhibitors, which are considered to be responsible for eliciting most of the intestinal and extraintestinal symptoms experienced by susceptible individuals. Although several approaches have been proposed to reduce the exposure to gluten or immunogenic peptides resulting from its digestion, none have proven sufficiently effective for general use in coeliac‐safe diets. Potential approaches to manipulate the content, composition, and technological properties of wheat proteins are therefore discussed, as well as the effects of using gluten isolates in various food systems. Finally, some aspects of the use of gluten‐free commodities are discussed.

Recent Progress and Recommendations on Celiac Disease From the Working Group on Prolamin Analysis and Toxicity

“…A "new" class of poorly digestible proteins in wheat, the amylase/trypsin-inhibitors (ATI), has received a lot of attention recently, but their potential role in the pathogenesis of CD needs further investigation (99)(100)(101).…”

Directed-Mutagenesis of Flavobacterium meningosepticum Prolyl-Oligopeptidase and a Glutamine-Specific Endopeptidase From Barley

“…Currently, there is only one approved therapy for celiac disease, which is the lifelong gluten abstinence (2,3). The effects of this prescription on individuals and families, makes it difficult to follow, due to cultural, social, technical, and financial concerns (4,5) as well as problems associated with the use of the gluten-free commodities (6,7). Therefore, alternative therapies are continuously being sought worldwide.…”

“…Gluten, the causal agent of celiac disease (8), is a complex mixture of polypeptides, which is also responsible for the unique technological properties to wheat (6,(9)(10)(11). Glutamine (Gln or Q, 35%) and proline (Pro or P, 15%) are the two major constituents of the gluten proteins, which give it its identity as prolamins (12).…”

“…A strict gluten-free diet ameliorates the intestinal mucosa morphology in a large number of celiac patients. However, a prolonged reliance on such a diet leads to often ignored unwanted effects, such as poor gut health due to changes in microbial population of the gut (18) or increase in the body mass index due to an excess consumption of starch laden low-fiber content processed foods (6). Therefore, alternative methods are continually being sought.…”

“…Among them, the processing methods include sourdough fermentation, use of gluten sequestering polymers or resins, food-grade enzymes of Aspergillus spp. (aspergillopepsin and dipeptidyl peptidase), microbial transglutaminase enzyme and flour derived from germinated or UV treated grains (6). Besides these processing methods, a large number of preventive methods, and intestinal barrier enhancing or immune targeted therapies are being developed and in various phases of clinical testing [cf.…”