Bitter Qualities Research Articles

ANALYTICAL AND BREWING SIGNIFICANCE OF A TRICYCLIC OXIDATION PRODUCT OF HUMULONE (TRICYCLODEHYDROISOHUMULONE)

Tricyclodehydroisohumulone (TCD) is an oxidation product of humulone formed during storage of hops. It is about 70% as bitter as isohumulone, and considerably more stable, both chemically and in the brewing process. When used to bitter beer by addition to the copper the overall utilization of TCD is around 75% and the quality of bitterness is excellent. TCD is a normal constituent of beer brewed from old hops, and accounts for a part of the non iso-α-acid bitterness of such beers. TCD mimics iso-α-acids in some standard analytical procedures for bitterness determination, and interferes in others; the analytical significance is discussed.

Cation and anion contributions to gustatory quality of simple salts

Curves of mean percentages of the four gustatory quality responses as a function of concentration of solutions of LiCl, KCl, lithium sulfate, and potassium sulfate were evaluated as to the relative contributions of the cation and anion to the quality. It was concluded that chloride ion, and sulfate ion to a lesser degree, were responsible for the salty quality. In the mid-range concentrations, potassium ion was responsible for the bitter quality, and lithium ion, by means of an ion-soliient interaction; was responsible for the sour quality reported. At the very low concentrations, at which all salts tested evoked sweet responses, a structure produced by a solvent-cation interaction was assumed to be responsible. The details of the presumed structure are still to be clarified. Although one ion in each salt is primarily responsible for a particular quality over a given concentration, the other ion usually modifies the effect.

Variability in gustatory quality identification

A total of 60 male and 60 female non-smoking undergraduates were tested on two gustatory screening tasks in which solutions representing the four basic taste qualities were used. The solution concentrations chosen were low, but supposedly distinct as to their qualities. Only 16% of the males were able to identify all solutions correctly, i.e., to a criterion of 4 correct out of 7 presentations, as compared to 34% of the females. A further 28% of the males consistently confused the sour and bitter qualities as did 10% of the females. A correction procedure used in one part of the experiment did not prevent this confusion. We suggest that the sour-bitter confusion may be the gustatory analogue of abnormal color vision.

The Mayor of Casterbridge and the Old Testament's First Book of Samuel: A Study of Some Literary Relationships

From one standpoint, the major theme of Thomas Hardy's The Mayor of Casterbridge is not “character is fate” or “man against himself,” but rather it is the conflict between generations. This is a very ancient subject matter, one of the archetypal themes noted by the Jungian literary psychologist Maud Bodkin, who traces it in classical Greek drama and in Shakespeare's Hamlet and King Lear? In Hardy's novel the conflicting generations are represented by Michael Henchard, the middle-aged corn factor and mayor, and Donald Farfrae, the energetic young Scotchman whose two-fold abilities, “the commercial and the romantic” (p. 162), while exercised with the best of intentions, prove deadly to his patron. Because of the ineluctability of this theme, it is necessary that the affection between the two men should turn to hate and that Henchard, as the older, should go under. The special bitterness of Henchard's inevitable failure is perhaps Hardy's characteristically pessimistic contribution. But we might also relate this quality of bitterness to the lack—increasingly in Hardy's time and almost totally in ours—of a generally accepted religious outlook which could transform Henchard's sufferings into a mitigating ritual and his death into a sacrificial symbol. Whereas Lear dies in the bosom of his family, as it were, surrounded by both his living and dead relatives, in full view of an awed and edified audience, Henchard's death is hidden from the eyes of all men except the faithful “fool” Whittle, whose report is necessarily limited to a few concrete particulars. Under the circumstances, Elizabeth–Jane's “what bitterness lies there!” (p. 337) is, at least on one level of the narrative, a final comment which every reader must echo.

忽布の苦味に關する釀造學的研究

Studying on the reason of the rough bitterness of hops, we found that it had almost no relations to the total resin contents of hops, the ratio of α-resin and β-resin, the oxidation and iodine value of total resins, and the sulphur dioxid, contents of hops. The soluble constituents in hop-straw were found to act upon the resins, and they determine the quality of bitterness.