Microbial Proteases in Baked Goods: Modification of Gluten and Effects on Immunogenicity and Product Quality

Abstract

Gluten-related diseases are a range of inflammatory disorders of the small intestine, characterized by an adverse response to gluten ingestion; therefore, the treatment is a gluten withdrawal. In spite of the increased market of gluten-free products, widely available breads with high acceptability are still missing due to the technological challenge of substituting the special gluten properties. Instead of using alternative ingredients for baking, some attempts have been done to decrease gluten immunogenicity by its enzymatic degradation with microbial proteases. Although the gluten immunogenicity reduction has been reached to an acceptable level, some quality parameters of the products are affected. This review focus on the use of microbial peptidases to prepare less immunogenic baked goods and their effect on product quality.

Recent developments in gluten-free bread baking approaches: a review

“…Unlike human gastrointestinal protease, PEPs can degrade gluten to amino acids or nontoxic peptides (less than nine amino acid residues) (Heredia-Sandoval et al, 2016). In addition, cereal germination can also degrade immunostimulatory gluten peptides and thereby diminish its toxic effects.…”

Screening of gluten hydrolyzing strains for food applications

“…Fecal strains of the genera Bacteroides and Bifidobacterium , such as Bacteroides fragilis and Bifidobacterium longum were shown to hydrolyze gliadin and gluten peptides (Laparra & Sanz, 2010; Sanchez et al., 2012). An advantage of proteolysis of gluten before its ingestion is the addition of cleavage sites in the proline‐rich sequences for gastrointestinal and brush‐border enzymes, which would enhance complete degradation of gluten (Heredia‐Sandoval et al., 2016). According to previous studies, degradation of gluten by probiotic strains could be attributed to their production of proteases.…”

“…According to previous studies, degradation of gluten by probiotic strains could be attributed to their production of proteases. The higher the protease activity, higher is the percentage of gluten degradation (Heredia‐Sandoval et al., 2016). Two of the food‐grade enzymes such as aspergillopepsin (ASP) from Aspergillus niger and dipeptidyl peptidase IV (DPPIV) from Aspergillus oryzae have been shown to have gluten hydrolyzing properties.…”

“…Several attempts have been made to decrease the immunogenicity of gluten by its enzymatic degradation with microbial proteases, instead of using alternative ingredients for baking (Heredia‐Sandoval et al., 2016). The principle of using the microbial proteases is that, unlike human gastrointestinal proteases, some microbial enzymes can cleave the peptide bonds next to proline residues, which frequently occur in gluten proteins (10–15% proline).…”

“…Thus, gluten proteins could be degraded to small peptides (<nine amino acid residues), with lower immunogenesity which is otherwise not possible by mammalian digestive enzymes (Helmerhost & Wei, 2014). These proteases are generally found in plants or microorganisms (e.g., bacteria or fungi) (Heredia‐Sandoval et al., 2016).…”