I like this discussion, this is some good info from brewing science and practice. In which he is talking about the grist, and specially how some breweries mill there grain.
"The newest designs use hammer-milled grists that are very fine indeed. Their are reasons for using the most finely ground grist that can be processed with the equipment available. The finer the particles the faster they hydrate on mashing, the faster the pre-formed soluble substances dissolve and the faster the extract leaches from the particles during sparging. Furthermore the enzymes have more ready access to their substrates in thoroughly disrupted grists. The surface/volume ratio of material is larger the smaller and more numerous the particles into which it is divided and so a finely divided grist provides a larger surface area on which enzymes can act and across which substances can diffuse. To varying extents the particles will be previous, permitting enzymes, substrates and the products of hydrolysis to enter and leave. In practice, finer grinding gives grists that, up to a given 'degree of fineness', yield higher extracts. Finer grinding is less advantageous with better modified malts (this is the basis of the analytical fine-coarse extract difference determination), but it is beneficial with many (perhaps all) mash tun adjuncts."
Later on he mentions,
"More finely ground grists are converted more quickly, saccharify faster, give higher extracts and sometimes the worts obtained are more fermentable and less turbid."
"By using very fine grists the whole mashing process can be carried out more quickly and with better extract yields . The levels of TSN and FAN increase and, at least with some grists, levels of soluble B-glucans increase and worst viscosities increase. Sometimes the flavor of the beer produced is improved, perhaps because the shortened mashing times allow less poorly flavoured material to be extracted."
In short Narziss,
seems to agree that a fine grind not only allows for easier extraction and faster hydrolysis of endosperm, but could also improve the FAN levels in beer which would mean better head formation, and could make a better tasting beer due to less tannin extraction and such. This is obviously a newer study I wonder which one is correct.
I would worry about what he says here, "Finer grinding is less advantageous with better modified malts (this is the basis of the analytical fine-coarse extract difference determination), but it is beneficial with many (perhaps all) mash tun adjuncts." Seems to go against what he is saying all along?????
I have never heard of milling with needles, very interesting.