Wort, beer

Megazyme International Ireland, 2001. See above. A booklet supplied with the /3-glucan determination kit containing directions for standard and streamlined procedures for [i-glucan determination in barley and oats, as well as the procedure for /i-glucan determination in malt, wort, beer, and spent grain. 

The estimation of iso-a-acids in wort, beer, and isomerized hop extracts is usually based on their light-absorption properties (Table 14.12). Measurements are made at 275 nm in acid solution or 255 nm in alkaline solution. Humulinic acids, which possess no bitterness, show similar light absorption to the iso-a-acids. Both a- and p-acids show appreciable absorption at the wavelengths mentioned so all these must be absent from the extract analysed. Hulupones exhibit 80-90% of the absorption of the iso-a-acids at these wavelengths but, since they are also bitter, it is often not regarded as so important to exclude them from the analysis. Beer produced by conventional wort boiling will contain only trace amounts of a-acids and humulinic acids, and iso-a-acids may be estimated directly on an isooctane extract of the beer. Worts, on the other hand, may also contain appreciable amounts of a-acids and isomerized hop extracts may contain a-acids, iso-a-acids, and humulinic acids. 

Fermentation vessels are usually 2-6 m (6 5-18 6 ft) deep, although deeper ones are used successfully. The material of construction should present an internal surface which is smooth, easy to clean, and hard to scratch or pit. It must not corrode, be subject to electrolysis, release toxic material, or deform. It should be chemically inert to wort, beer and to cleansing and sterilizing solutions. Expensive or deformable materials which are otherwise suitable for vessel construction are often used as liners for less expensive or more durable materials (Tables 19.1 and 19.2). 

Acetobacter Wort, beer dispenses, and cask-conditioned ales and barrel-aged ales, brewery biofilm Sour, vinegary Hazy, ropiness Acetic acid... 

Glucano- bacter Wort, beer dispense and cask-conditioned ales Sour, vinegary Hazy Acetic acid, acetate... 

As the beer progresses through the brewery it comes into contact with vessel surfaces, pipes, and fittings, all of which can harbor infection, particularly on the cold side of the brewery after wort clarification. Any surface that comes into contact with wort, beer, or yeast should be thoroughly cleaned and sterilized, that is, vessels, piping. 

McMurrough I, Hemigan G P, Cleary K 1985 Interactions of proteases and polyphenols in worts, beers and model systems. J Inst Brew 91 93-100... 

Chloroform-acetic acid-water 3 6 1 1 3 1 mono- and oligosaccharides Wort, beer sulfuric acid HPTLC MD, 1st and 2nd run 3rd run 98... 

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