The purpose of malting is to produce enzymes in the grain of the grain and to make defined changes to its chemical components (Kunze, 1996b). The malting process includes cleaning and sorting barley broths, soaking the grain in water, germinating the grain, and finally drying and drying in the oven (Figure 15.1). The third and final step in the malting process is the right to go. Convection heat treatment dries out the green malt to prevent further germination. If germination continued, the kernel would continue to grow and all starch reserves needed by the brewer would be used up by the growing plant. In most malts, moisture is first removed from the sprouted grain – this is called wilting. Further drying further reduces the moisture content and prepares the malt for the development of taste and colour. Other important results obtained during the cooking process are enzyme activity and brittleness. It is the controlled variations of this stage that bring out the wide range of malt colors and flavors used by brewers in making their unique and distinctive beers and lagers. The soaking step moisturizes the seed, allowing germination to begin. Germination allows the embryo to develop under controlled conditions, allowing the sperm to develop enzymes that break down or alter the structure of the endosperm.

Other enzymes hydrolyze and dissolve the reserve strength and proteins of the endosperm. The amount of soluble matter, often referred to as an “extract”, is an important quality parameter used to predict the amount of beer or spirits a malt can produce. The oven is the last step in malting and stops the growth of the embryo by removing moisture. Temperatures and cooking times are particularly important because they determine the final enzyme content of a malt, the development of desirable flavours, flavours and colours, and the concentration of undesirable flavours and flavours (Table 2). Different types of equipment can be used to produce malt. In traditional ground malting, the grains germinate in a thin layer on a solid bottom, and the grain is manually raked and turned to keep the grains loose and aerated. In a modern malting plant, the process is more automated and the grain is sprouted on a split bottom to allow air to be pushed through the grain bed. Large mechanical turners, for example Saladin boxes, keep the bed much thicker loose with increased productivity and better energy efficiency. The malting plant typically uses cereal grains, especially barley1571, which germinate when soaked in water, developing the enzyme capable of hydrolyzing the starch in the grain to obtain glucose and maltose.

During germination, barley changes its heterodispersity only slightly. In general, there is a correlation between the quality of the malting plant and the protein content of the malted substrate, as shown by the germination of wheat. The germination capacity as well as the activity of beta-amylase and protease in the substrate are positively correlated with protein content.1572,1573 Subscribe to America`s largest dictionary and get thousands of other definitions and an advanced search – ad-free! Barley must be stored safely to maintain the potency of the grain for germination. Storage in a malting plant is usually done in vertical steel or concrete silos for ease of handling, but can be done in shallow warehouses if large quantities of grain need to be stored. The grain is stored in such a way as to be protected from moisture and pests. A typical silo stores between 5,000 and 20,000 tonnes of clean, dry barley ready for malting. Years of intensive research and development lead to the perfect technological solution for craft malts. Kaspar Schulz is the oldest brewery manufacturer in the world and has been laying the foundations for good beer since 1677. In its tenth generation as a family business based in Bamberg – at the heart of Germany`s brewing culture – it is of particular importance. The integration of “tradition and technology” is what they do and have always done. In fact, the company has been developing and supplying complete malting systems since 1879.

The malting process consists of several steps. Malt is considered relatively stable after production, if the grain moisture is less than about 12% (w/w), and can be stored under suitable conditions for many months. Low humidity and special attention to possible fungal growth are essential during prolonged storage. The final color of the malt depends on the oven regime used to dry the malt so that it is stable during storage. So-called storage malts are dried at temperatures well below 100 °C, while alemalt is dried at about 100 °C. These higher temperatures stimulate non-enzymatic browning reactions between sugars and free amino compounds, resulting in a darker color and generally a higher degree of flavor. Basically, however, both still retain the enzymatic activity essential to the brewing process. The degree of enzyme development is called “modification” and has an impact on how malt is used in the brewery. Malting is the limited germination of cereal grains in moist air under controlled environmental conditions. Traditionally, millet and sorghum malting in southern Africa was carried out by first soaking the grain in a slice of grass in a river, then germinating the grains in a bag or spreading them on a bottom for 2-3 days (Gadaga et al., 1999). Subsequently, the malt was sun-dried and finely ground. The biggest change in grain caused by malting is the mobilization of alpha and beta-amylases from the grain.

In slurries to which malt is added, the action of malt-alpha-amylase reduces the viscosity of the pulp by hydrolysis of starch. This slimming effect is very important when porridge is used as weaning food or food for the infirm. The nutritional value of any food is directly related to its solids content. Thus, a porridge of 30% solids has three times the nutrient content of one in 10%, but these porridges are too rigid to be consumed by infants and infirm. A reduction in viscosity can be achieved by adding malted grains. For example, adding sorghum malt to 25% solid pearl millet pulp to obtain a total solid of 30% reduced pulp viscosity by over 6000 cP to an acceptable level of only 2500-3000 cP (Thaoge et al., 2003). In addition, porridge can also be made tastier by the action of malt-beta-amylase (i.e. the production of maltose and therefore the increase of sweetness). The total values of amylase activity, called diastatic force, in pearl millet malt (Pelembe et al, 2002) and finger millet malt (Gomez, 1994) were similar to those of sorghum malt. However, pearl millet malt appears to have more beta-amylase activity, approaching barley malt levels (Pelembe et al., 2004). The malt grain used to dilute porridges is called amylase rich flour (RFA) or “potency flour” (Alnwick et al., 1988).

The use of RFA in conjunction with safe and hygienic practices has been strongly recommended for weaning food preparation in Africa. Grain malting also has many other effects on the composition of the grain of the cereal, most of which have a positive effect on its nutritional value (Taylor and Belton, 2002). The composition of essential amino acids is improved, as well as the digestibility of proteins and starch. The content of B vitamins increases and the bioavailability of minerals is improved by the destruction of phytate. Malting barley has several purposes. On the one hand, the development of amylolytic enzymes is essential for the subsequent brewing operation, as they are necessary for the formation of fermentable sugars from malt starch. This diastatic force is more than sufficient for conventional brewing, so it can be diluted to some extent with non-diastatic materials such as specialty syrups and malts. Secondly, on a practical level, it is desirable to reduce or eliminate the β-glucans present in barley. These form gels that significantly slow down or even stop the separation of the sweet wort from the residual solid. Third, enough free amino acids must be released, either during malting or during the brewing phase of beer production, to support yeast growth, which is needed in the early stages of fermentation.

Finally, in terms of taste, “grainy” or “green” flavors must be eliminated to be replaced by desirable “malty” flavors. Other aspects are gaining importance, namely the reduction of agrochemical residues during malting, which means that smaller quantities end up in the final beer. This also applies to the presence of barley microflora, which may be accompanied by a number of mycotoxins. Malt is often called the “soul of beer” and is over 4,000 years old. Malt is one of the four essential ingredients used in craft beer production. It is the malt that adds color, aroma, flavor and body to any beer and lager, and can make any beer stand out from the rest. Although a variety of grains have been used for brewing, barley is the preferred grain for beer. Barley itself cannot be fermented into alcohol, and so it is converted to malted barley or malt in a process called malting.

The product of the malting plant is used to make a nutritious broth, which in principle resembles the LB broth used for the growth of E. coli. coli. This nutritious broth, known as seasoning, is used as a culture medium for yeast. It is made by adding water to the malt, which is then pureed (Figure 16.6). (Sour porridge is slightly different. Microbes are allowed to partially break down the mash, causing it to acidify, giving the resulting product a sour taste.) Malt enzymes then catalyze reactions to maltose, glucose and other sugars. After this maturation of the puree, it will exist as slurry containing seed residues, proteins, and simple and complex carbohydrates (Figure 16.7).