“oast house” at page 621 states: “Oast houses, or ‘hop kilns’ as they are also known …” To be more specific, the buildings for drying hops seem to have been called oast houses (from a mostly Southern English dialect word meaning “kiln”) in Kent and Sussex, but hop kilns in Surrey, the West Midlands and other areas outside the far south-east corner of England. The distinctive tall round buildings mentioned in this entry are called “roundels”.
“oats” at page 622 needs to say that records both in Britain and in Continental Europe show that oats were a frequent ingredient in ale in the medieval period, together with wheat and barley, being mentioned in accounts of brewing in, eg, the records of St Paul’s Cathedral in London in the 13th century (see William Hale Hale (sic), The Domesday of St Paul’s in the Year MCCXXII, London, Camden Society, 1858, and also VT van Vilsteren, “De oorsprong en techniek van het brouwen tot de 14de eeuw”, mentioned in Richard Unger, //Beer in the Middle Ages and the Renaissance//), were still being used by West Country brewers early in the 16th century in their ales, were mentioned in an ingredient in March beer by Gervase Markham in 1615 (see The English Housewife) and were also used by Norwegian home brewers until the 20th century – see Odd Nordland, Brewing and Beer Traditions in Norway, 1969.
“old ales” at pages 625-626 suffers from the misconception that “beer style” is a concept that can be usefully applied to brewing before the 20th century, and that there was such a “style” as “old ale” in the 18th and 19th centuries. It fails to appreciate that “old ale” as a style is strictly a 20th century phenomenon. It also fails to recognise that in the 18th and 19th centuries there was one type of malt liquor, “ale”, and that this could be sold new, when it would be called “mild”, or aged, when it would be called “old”. It states that “at first little separated [old ales] from barley wine”, but “barley wine” as a concept or “style” is, again, a 20th century idea (for a discussion of these issues see here). It fails to understand that an 18th or 19th century brewer would not have set out to brew an “old ale” but a strong ale, which he might or might not age. It states that “Old ales were normally fermented only from the first, high-gravity runnings of the mash, often in a parti-gyle brewing process”, which fails to understand what parti-gyling was: the mixing of the different runnings. It states that after mashing the grain for an “old ale”, “the second runnings were then fermented as brown ales or other medium-strength beers”, failing to understand that ales were frequently (and indeed after the middle of the 18th century almost universally) pale in colour, and that there WAS no brown ale in Britain between about 1750 and about 1900. It states that “Long aging in wood allowed the ale … to acquire some flavour from the raw wood”, but brewers went to great effort to acquire close-grained oak for their casks, precisely to avoid woody flavours. There is, in addition, no evidence to say aged ales would have picked up wood flavours. It states that “Old ales were invariably higher-alcohol beers of perhaps 6% or 7% alcohol by volume”, but this is far too low: 7.5% abv was standard for mild ale, and ales kept for long periods could be substantially stronger than that, up to 10 or 11 per cent abv. It states that “the original old ales were literally old by beer standards of the day, matured for months and often years in wooden casks”, but lengthy ageing for months was perfectly normal for all sorts of ale and beer. It states that “‘old ales’ … have kept the original dark colour range …” but the original ales, mild and old, in the 19th century were pale, made from pale malt, as 19th century brewing books show. See the commentary on this entry at Shut up About Barclay Perkins.
“oxidation,” in this entry it states: “A good example of the importance of oxygen in brewing is the perhaps the oxidation of the carbohydrate glucose in the process of yeast respiration.” This is not the case as brewers yeast in does not respire aerobically during normal brewing conditions, instead it ferments. Due to the Crabtree effect this is even the case when the yeast is first pitched and oxygen levels are high.