The generic term "malt" may indicate:

• barley malt
• corn malt
• wheat malt
• rye malt
• and other cereals

Studies

Barley malt  is traditionally used to flavor the foods and it is the product of the germination of barley. During germination, the non-starch polysaccharides (NSPs) in the cell wall of barley, constituting mainly arabinoxylans and β-glucans, are solubilised and partly degraded into smaller molecules (1).

Health

 Barley and germinated barley contain large quantities of glutamine (2) an important substrate for colonic mucosa. Glutamine is easily degraded by the low pH in the stomach, but some of the glutamine is protected by the dietary fibre during digestion in the stomach (3) and therefore reaches the colon. In this study, starting from the premise that Butyric acid, one of the key products formed when β-glucans are degraded by the microbiota in the colon, has been proposed to be important for colonic health. Glutamine bound to the fibre may have similar effects once it has been liberated from the fibre in the colon. Both β-glucans and glutamine are found in high amounts in malted barley. Lactobacillus rhamnosus together with malt has been shown to increase the formation of butyric acid further in rats (4).

The addition of corn makes the mixture sweeter and more pleasant to taste.

References__________________________________________________

(1) Jamar C, Jardin Pd, Fauconnier M. Cell wall polysaccharides hydrolysis of malting barley (Hordeum vulgare L.): a review. Biotechnol Agron Soc Environ. 2011;15:301–13

Abstract. Malting quality results from the different steps of the malting process. Malting uses internal changes of the seed occurring during germination, such as enzymes synthesis, to obtain a good hydrolysis process and the components required. Among the three main hydrolytic events observed, that are namely starch degradation, cell wall breakdown and protein hydrolysis, an efficient cell wall polysaccharides hydrolysis is an essential condition for a final product of quality. Indeed, because of the physical barrier of the cell wall, cell wall polysaccharides hydrolysis is one of the first steps expected from the process to gain access to the cell components. Moreover, viscosity problem and haze formation in malting industry are related to their presence during the process when inefficient degradation occurs, leading to increased production time and cost. Understanding the key elements in cell wall degradation is important for a better control.(1-3, 1-4)-β-glucans and arabinoxylans are the main constituents of cell wall.(1-3, 1-4)-β-glucans are unbranched chains of β-D-glucopyranose residues with β-(1, 3) linkages and β-(1, 4) linkages. Arabinoxylan consists in a backbone of D-xylanopyranosyl units linked by β-(1-4) bonds connected to single L-arabinofuranose by α-(1→ 2) or α-(1→ 3)-linkages. Degradation of (1-3, 1-4)-β-glucans is processed by the (1-3, 1-4)-β-glucanases, the β-glucosidases and the β-glucane exohydrolases. It seems that the (1-3)-β-glucanases are also involved. Arabinoxylans are mainly decomposed by (1-4)-β-xylan endohydrolase, arabinofuranosidase and β-xylosidase.

(2)  Robertson JA, I'Anson KJA, Treimo J, Faulds CB, Brocklehurst TF, Eijsink VGH, et al. Profiling brewers’ spent grain for composition and microbial ecology at the site of production. LWT Food Sci Technol. 2010;43:890–6

Abstract. Brewers' spent grain (BSG) is a readily available, high volume low cost byproduct of brewing and is a potentially valuable resource for industrial exploitation. The variation in BSG composition and the implications for microbiological spoilage by a resident microflora might affect the potential to use BSG as a reliable food-grade industrial feedstock for value-added downstream processing. Fresh samples of BSG from a range of 10 breweries have been analysed for their microbial and chemical composition. The results show that a resident microflora of mainly thermophilic aerobic bacteria (<107g-1 fresh weight) persists on BSG. This population is susceptible to rapid change but at the point of production BSG can be considered microbiologically stable. Chemically, BSG is rich in polysaccharides, protein and lignin. Residual starch can contribute up to 13% of the dry weight and BSG from lager malts has higher protein content than that from ale. In general, at the point of production, BSG is a relatively uniform chemical feedstock available for industrial upgrading. Differences between breweries should not present problems when considering BSG for industrial exploitation but susceptibility to microbial colonisation is identified as a potential problem area which might restrict its successful exploitation.

(3)  Kanauchi O, Agata K  Protein, and dietary fiber-rich new foodstuff from brewer's spent grain increased excretion of feces and jejunum mucosal protein content in rats  Biosci Biotechnol Biochem. 1997 Jan; 61(1):29-33.

Abstract. We made a new protein-rich and fibrous foodstuff by milling and sieving brewer's spent grain. This product contained glutamine-rich protein and the dietary fibers cellulose, hemicellulose, and lignin. We called this product germinated barley foodstuff (GBF). GBF had the effect of increasing fecal dry weight and number of feces and of significantly increasing jejunum mucosal protein content in rats over the cellulose group. In GBF, Gln-rich protein is thought to have strong chemical bonds with dietary fiber, an arrangement which would be important in the way these physiological effects arise. As dietary supplements of Gln or dietary fibers (i.e., cellulose, hemicellulose, lignin, and a mixture of these) did not improve defecation and jejunum mucosal protein simultaneously, the effects of GBF are thought to be caused not by the individual ingredients, but by the combination of protein with dietary fiber.

(4)   Zhong Y, Nyman M. Prebiotic and synbiotic effects on rats fed malted barley with selected bacteria strains. Food Nutr Res. 2014 Oct 6;58. doi: 10.3402/fnr.v58.24848. eCollection 2014.

Abstract. Background: Butyric acid, one of the key products formed when β-glucans are degraded by the microbiota in the colon, has been proposed to be important for colonic health. Glutamine bound to the fibre may have similar effects once it has been liberated from the fibre in the colon. Both β-glucans and glutamine are found in high amounts in malted barley. Lactobacillus rhamnosus together with malt has been shown to increase the formation of butyric acid further in rats. Objective: To investigate whether Lactobacillus rhamnosus 271, Lactobacillus paracasei 87002, Lactobacillus plantarum HEAL 9 and 19, and Bifidobacterium infantis CURE 21 affect the levels of short-chain fatty acids and glutamine in caecum and portal blood of rats fed barley malt. Design: The experimental diets were fed for 12 days. The daily dose of the probiotic strain was 1×10(9) colony forming units and the intake of fibre 0.82 g/day. Results: The malt mostly contained insoluble fibre polymers (93%), consisting of glucose and xylose (38-41 g/kg) and some arabinose (21 g/kg). The fibre polysaccharides were quite resistant to fermentation in the rats, regardless of whether or not probiotics were added (25-30% were fermented). Caecal and portal levels of acetic acid decreased in the rats after the addition of L. plantarum HEAL 9 and L. rhamnosus 271, and also the levels of butyric acid. Viable counts of Lactobacillus, Bifidobacterium and Enterobacteriaceae were unaffected, while the caecal composition of Lactobacilli was influenced by the type of strain administrated. Portal levels of glutamine were unchanged, but glycine levels increased with L. plantarum HEAL 9 and 19 and phenylalanine with L. rhamnosus 271. Conclusions: Although the probiotic strains survived and reached the caecum, except B. infantis CURE 21, there were no effects on viable counts or in the fermentation of different fibre components, but the formation of some bacterial metabolites decreased. This may be due to the high proportion of insoluble fibres in the malt.