The extraction of phenolics (anthocyanins, total phenolics and tannins) and pigmented tannin evolution in Merlot red wines made using three different winemaking techniques were evaluated over one year. Traditional maceration (TM) (two plunges per day), half plunging (half) and no plunging (NP) methods were compared using triplicate 12 kg vinification. No pre-fermentation maceration occurred and a 15-day fermentation and post-fermentation period was used. The wines were analysed daily during the 15-day maceration period and regularly after pressing during the next 11 months. Phenolic, tannin and colour measurements were analysed using UV/Vis spectral readings processed using the AWRI WineCloud TM . At the end of the 15-day maceration, total phenolics, total pigment and free anthocyanins were significantly lower in concentration in the TM treatment compared with NP. The tannin concentration also was significantly lower from days 10 to 12. Pigmented tannin was consistently at higher concentrations in the TM treatment, although not significantly so, during maceration. The significant differences were maintained as the wine developed over the next 11 months; however, the NP trial wine displayed increased pigmented tannin development compared with the TM, being significantly higher in pigmented tannin from about day 90. Higher colour and phenolic extraction in the NP trial led to higher stable colour development in the resulting wines, with the winemaking having an important effect in modifying the pigment profile of the wines. General wine quality parameters did not differ significantly between the three treatments.

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The nutritional diseases designated as beri beri, scurvy and pellagra are currently believed to be induced by a deficency in the diet of some undefined but essential constituent or constituents. From the experimental standpoint the pigeon is peculiarly sensitive when the diet fails to provide a sufficiency of these unknown but essential food substances, and polyneuritis develops. The symptoms of polyneuritis in birds closely resemble those of beri beri in man. The guinea pig hal proved to be especially susceptible to scurvy. On the other hand, pellagra in the ordinary laboratory animals is rarely mentioned.We have accomplished the experimental production in dogs of a diseased condition which cosely resembles human pellagra. The characteristic phenomena are readily evoked by feeding these animals a diet consisting of boiled (dried) peas, cracker meal and cotton seed oil, or lard. The ingestion of suitable quantities of meat causes the symptoms of disturbed nutrition to disappear. On the other hand, if the amount of meat contained in a selected mixed diet is insufficient, the same evidences of abnormality may be exhibited. The symptoms appear in varying periods of time which may be altered by changes in the character of the diet.The onset of the symptoms is generally very sudden. Usually the first abnormal manifestation in dogs is a refusal to eat, and cursory examination reveals nothing to account for the loss of appetite. The animal lies quietly in its pen and is apathetic. After continued refusal to eat for a day or two, the mouth of the dog presents a peculiar and characteristic appearance, in that the inner surface of the cheeks and lips, and the edges of the tongue, are so covered with pustules as to give the impression of a mass of rotten flesh. The odor from the tissues is foul. The mucous lining of the mouth comes away in shreds when stroked with absorbent cotton. Intense salivation exists. The teeth remain normal. A bloody diarrhoea is present, attempts at defecation being very frequent, and resulting in the passage of little more than a z95

THE many experiments of Kiihne and Chittenden and their co-workers', carried on during the past few years with a view to acquiring more definite knowledge concerning the composition and relationship of the primary cleavage products formed in the digestion of the individual proteids, have been gradually extended, but have still been confined mainly to the albumins from the animal kingdom. Neumeister2 bas recorded some interesting results obtained in the digestion of phyto-vitellin, but aside from these little is known regarding either the composition or properties of the products formed in the gastric digestion of plant proteids. We have chosen for our study the gluten-casein of wheat as described by Ritthausen, principally because it appears to be the chief proteid constituent of gluten, and hence of wheat bread, and as such must constitute a large proportion of the vegetable proteids of our daily food. It is certainly questionable whether gluten exists as such in fresh wheat kernels, especially in the light of the researches of Weyl and Bischoff', S. Martin and others, who ascribe the formation of gluten to a special ferment action when flour is mixed with water. Furthermore, there is the possibility, in the preparation of gluten-casein, that the prolonged action of dilute alkalies or even of water on the gluten, or on the globulin bodies4 which possibly con-1 See Zeitschrift fiir Biologie, also Studies from the Laboratory of Physiological Chemistry, Yale University, Vols. i-iII. 2 Zeitschrift fur Biologie, Bd. xxiiI. p. 402. 3 Bericht. d. deutsch. chem. Gesellschaft, xiii. p. 367. 4 Oeitschriftfuir Physiol. Chem. Bd. I. p. 100.

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IN the digestion of proteid matter by pepsin-hydrochloric acid there are three well-defined products or classes of products, viz. acid-albumin or syntonin, albumoses or proteoses, and peptones. We look upon the first as the initial product of gastric digestion and identify it by its wellknown precipitation by neutralization. In the filtrate, the albumoses can be detected by saturation of the fluid with sodium chloride and addition of acetic acid, or best by saturation with ammonium sulphate, while the true peptones (amphopeptone) are found in the filtrate from the latter precipitate, after dilution with water, by testing with cupric sulphate and potassium hydroxide1. True peptones are bodies not precipitated by saturation with ammonium sulphate, and are t-he final products of pepsin digestion.Since the discovery of the albumoses and of their characteristics', frequent study of digestive mixtur.es has given convincing proof that in an ordinary gastric digestion of any common proteid only a comparatively small amount of peptone is formed'; peptorlization in the true sense of the word results only from the long-continued action of pepsinacid, and even then complete peptonization rarely if ever occurs. The albumoses or, in a broader sense, the proteoses, are to be considered as the primary products of gastric digestion, while peptones are the end products of proteolytic action, the latter being formed by the gradual 1 Taking great care to add sufficient potassium hydroxide to decompose all of the ammonium salt present.