224 TECHNOLOGY OF CEREALS TABLE 9.2 fuel,25-30%; Characteristics of a selection of malts electricity, 15-20%: Malt type Extract Moisture Colour Final kiln wages,15-20%; (EBC) temperature repairs/maintenance, 10-20%; miscellaneous. 15-25% 44742 As with many wet processes of cereals the costs Crystal malt 100-30 00550 of water treatment before discharge are increasing as standards become more stringent. The Bio- Roasted malt logical Oxygen Demand (BOD)load from a Roasted barley 27 51000-1550230 30,000 tonnes per annum maltings is equivalent Of all the malts listed only ale and lager malts contain to a population of about 9000 people(Gibson enzymes 1989) Source: Palmer, 1989. Reproduced by courtesy of Aberdeen ale malt compared with that of barley is shown Malt pr。 duction in Table 9. 1. The characteristics of brewers malts Palmer(1989)reports that about 17 million of various types are given in Table 9.2 tonnes of barley are used annually, world-wide, to duce 12 million tonnes of malt and about 970 Ageing million hectolitres of beer. This represents about 10%of world barley production 6 Before use it is necessary to mill kilned malts it is customary to delay this process to permit By-products of malting moisture equilibration. Kilning effects drying rapidly and in individual grains a gradient exists The main by-product of malting is called 'malt from a higher inner to a lower outer(husk) sprouts. They are separated from kilned malt by moisture content. Differences in a malt of 3-5% passing the malt through revolving reels or a wire m.c.may be 4 or 5%(1-3% outside to 5-8% screen. They account for 3-5% of product and inside). Unless equilibrated, agglomeration of the they are incorporated into stock feeds. Typically damper parts can reduce extraction potential and they contain 25-34% N-compounds, 1. 6-2.2 undue fragmentation of dry husk leads to haze fat, 8.6-11.9% fibre, 6.0-7 1% ash and 35-44% in the extract(Pyler and Thomas, 1986). Storage N-free extract(Pomeranz, 1987 for up to 3 months may be used. As specifications become increasingly sensitive to moisture content Non-brewing uses of malt the conditions of storage progressively include humidity control(Palmer, 1989 Milled barley malt is used as a high diastatic supplement for bread flours which are low in Energy consumption and other costs natural diastatic activity, and as a favour supple ment in malt loaves. Malt extracts and syrups are The Energy Technology Support Unit published produced by concentrating worts by evaporation a report in 1985 of a survey of United Kingdom Malt is also used in the manufacture of malt maltsters. Specific energy consumed per tonne of vinegar malt ranged from 2. 48 to 6.81 G], with a weighted and electricity. Power costs comprised grain Adjuncts handling and process requirements Although malt derived from barley is generally Estimates of proportionate costs, including considered to be the superior feedstock for brewing these values are given by gibson(1989)as and distilling, it is common practice in many224 TECHNOLOGY OF CEREALS TABLE 9.2 fuel, 25-30%; Characteristics of a Selection of Malts electricity, 15-20%; Malt type Extract Moisture Colour Final kilning wages, 15-20%; (“/kg) (Oh) (“EBC) temperature repairs/maintenance, 10-20%; (“C) miscellaneous, 15-25%. Ale* 305 4.0 5.0 100 As with many wet processes of cereals the costs Lager* 300 4.5 2.0 80 Cara pils 265 7.0 25-35 75 Crystal malt 268 4.0 100-300 75 of water treatment before discharge are increasing 70-80 150 as standards become more stringent. The Bio- Amber malt 280 2.0 Chocolate malt 268 1.5 900-1200 220 Roasted malt 265 1.5 1250-1500 230 logical Oxygen Demand (BOD) load from a Roasted barley 270 1.5 1000-1550 230 30,000 tonnes per annum maltings is equivalent * Of all the malts listed only ale and lager malts contain to a PoPulation of about 9000 People (Gibson, enzymes. 1989). Source: Palmer, 1989. Reproduced by courtesy of Aberdeen University Press. ale malt compared with that of barley is shown in Table 9.1. The characteristics of brewers malts of various types are given in Table 9.2. Ageing Before use it is necessary to mill kilned malts but it is customary to delay this process to permit moisture equilibration. Kilning effects drying rapidly and in individual grains a gradient exists from a higher inner to a lower outer (husk) moisture content. Differences in a malt of 3-5% m.c. may be 4 or 5% (1-3% outside to 5-8% inside). Unless equilibrated, agglomeration of the damper parts can reduce extraction potential and undue fragmentation of dry husk leads to haze in the extract (Pyler and Thomas, 1986). Storage for up to 3 months may be used. As specifications become increasingly sensitive to moisture content the conditions of storage progressively include humidity control (Palmer, 1989). Energy consumption and other costs The Energy Technology Support Unit published a report in 1985 of a survey of United Kingdom maltsters. Specific energy consumed per tonne of malt ranged from 2.48 to 6.81 GJ, with a weighted average of 3.74 GJ. Quoted costs included fuel and electricity. Power costs comprised grain handling and process requirements. Estimates of proportionate costs, including these values are given by Gibson (1989) as: Malt production Palmer (1989) reports that about 17 million tonnes of barley are used annually, world-wide , to produce 12 million tonnes of malt and about 970 million hectolitres of beer. This represents about 10% of world barley production. By-products of malting The main by-product of malting is called ‘malt sprouts’. They are separated from kilned malt by passing the malt through revolving reels or a wire screen. They account for 3-5% of product and they are incorporated into stock feeds. Typically they contain 25-34% N-compounds, 1.6-2.2% fat, 8.6-11.9% fibre, 6.0-7.1% ash and 3544% N-free extract (Pomeranz, 1987). Non-brewing uses of malt Milled barley malt is used as a high diastatic supplement for bread flours which are low in natural diastatic activity, and as a flavour supple￾ment in malt loaves. Malt extracts and syrups are produced by concentrating worts by evaporation. Malt is also used in the manufacture of malt vinegar. Adjuncts Although malt derived from barley is generally considered to be the superior feedstock for brewing and distilling, it is common practice in many