Addition Of Lactic Acid Research Articles

底棲魚の鮮度について

The AMANO's method for the evaluation of the fish freshness applied by W. WALKIEWICZ's was found to be unapplicable to bottom fish (Table 1) as well as squid. It is considered that this was caused by the high pH value of those muscles which may be ascribed to the small quantity of lactic acid and high trimethylamine oxide content, having the buffering capacity on acid side below pH 6.25, in comparison with the pelagic fish. In order to justify this consideration, the determination of lactic acid and trimethylamine oxide, was carried out. The results are shown in tables 2, 3 and 4. The pH value of the mixed solution of trimethylamine oxide and lactic acid was measured as shown in Table 3 and the effect of addition of trimethylamine oxide and lactic acid on the pH value of histidine solution (958mg%) was observed as indicated in Table 4. The pH value of bottom fish and squid generally is given as above 6.2, which is due to the small quantity of lactic acid and large amount of trimethylamine oxide. Owing to this high value the AMANO's method is not applicable for bottom fish and squid.

Effect of physiologic acids on electrolytes in rat diaphragm.

The effects of physiologic acids on muscle electrolytes were studied by incubating rat hemidiaphragms in Krebs-Ringer solution or blood at pH 7.4 and 6.8. With the addition of acetic, lactic or beta-hydroxybutyric acid to depress the pH, the sodium and potassium contents of muscles incubated in Krebs-Ringer solution were the same at each pH. This is in contrast to the efflux of these cations previously observed on adding hydrochloric acid to this medium. Using heparinized rat blood as the medium, the effect of hydrochloric acid was the same as in Krebs-Ringer solution. With acetic acid however, the pattern was reversed. Muscles in blood acidified with acetic acid actually retained more potassium than the controls at pH 7.4. An increased Pco2 to depress the pH in blood did not affect the potassium content, but there was a gain of sodium in the muscles in the more acid blood so that the net cation content increased. In contrast to the physiologic acids which can penetrate the cells as intact molecules, hydrochloric acid produces an essentially extracellular acidosis. Hydrochloric acid therefore causes a displacement of intracellular cation as hydrogen ions penetrate the cell. With blood, which is better buffered than the intracellular fluid, acetic acid and carbon dioxide depress the intracellular pH more than the extracellular pH. The pH gradient across the membrane is then analogous to that with hydrochloric acid but in the opposite direction resulting in a movement of cations into the cells.

Dependence of the phagocytic reaction of leukocytes on their carbohydrate metabolism

Glucose and insulin added together to the media causes a considerable increase of phagocytic activity of leukocytes of the human blood. Glucose and insulin added separately decrease this activity. Elimination of glycolysis induced by the addition of monoiodoacetic acid, likewise diminishes phagocytosis: this effect is abolished by the addition of lactic acid. The phagocytic activity of leukocytes depends to a great extent on their carbohydrate metabolism.

Studies on Spontaneous In Vitro Autohemolysis in Hemolytic Disorders

Abstract Measurements of spontaneous lysis (autohemolysis) of red cells in sterile defibrinated blood after 48 or more hours of incubation at body temperature were found useful in the investigation of certain hemolytic states. Abnormally rapid autohemolysis was demonstrated most consistently in hereditary spherocytosis, but was also found in other types of spherocytosis and in several examples of non-spherocytic hemolytic anemia. Autohemolysis above the normal range can be regarded as strong presumptive evidence of a hemolytic disorder, but a normal rate of autohemolysis by no means excludes the possibility of a hemolytic process in any given case. Abnormalities of hereditary spherocytes causing increased autohemolysis were shown to be correlated with those responsible for spherocytosis as reflected in osmotic fragility tests. There appeared to be closer correlation with abnormalities causing increased osmotic fragility of the cells after 24 hours incubation. The autohemolysis test and the osmotic fragility test on incubated red cells were found to be equally sensitive in their capacity to detect spherocytosis of the hereditary type. Addition of adenosine, guanosine or inosine caused moderate to marked reduction in autohemolysis of nearly all types of red cells tested. Lysis of incubated spherocytes from active cases of autoimmune hemolytic disease was more markedly inhibited by a small amount of adenosine than was the lysis of hereditary spherocytes. Glucose regularly caused marked inhibition of autohemolysis of hereditary spherocytes and of red cells from patients with acute leukemia. The effect of glucose on HS red cells might have been due in part to a lowering of pH by formation of lactic acid since acidification of the blood with lactic, citric or hydrochloric acid also caused substantial reduction in autohemolysis. Glucose caused slight to marked increase in lysis of red cells in certain other cases of spherocytosis, notably in autoimmune hemolytic disease and in myeloid metaplasia. Addition of lactic acid to the blood from several of these patients had similar effect. In 2 atypical cases of chronic spherocytosis, with hematologically normal relatives, autohemolysis was accelerated by addition of glucose to the blood samples. Adenosine had little effect until after splenectomy when both glucose and adenosine inhibited hemolysis, much the same as in blood from typical cases of hereditary spherocytosis. It seems likely that when the abnormalities of carbohydrate metabolism of the red cells in certain hemolytic disorders are better understood, measurements of autohemolysis may be modified so as to enhance their usefulness in detecting and differentiating the various hemolytic states. It also seems likely that further studies on in vitro autohemolysis will help to elucidate some hemolytic mechanisms operating in vivo.

釀造の諸條件と前年度試釀酒の火持性について

Three different kinds of sake were brewed by using the same tane koji (seeds of Aspergilli) consisting of a mixture of equal amount of the two kinds of Aspergilli strains C and D used inthe sake brewed in the previous year, with the moto (yeast culture) prepared by (1) the quick method with the addition of lactic acid, (2) the saccharification method at a higher temperature (55-58°C.), and (3) the “yamahai” method at a lower temperature without lactic acid. Thus thequalities of sake were compared according to the brewing conditions with the same tane koji. They were different not only by the brewing conditions, but also by the properties of Aspergilli. It seemed that particularly the aroma and the durabilities in storage of sake were more influenced by the Aspergilli.Most of the strains of Aspergilli isolated from the de-koji (koji made from the cultivation of mixture of two kinds of Aspergilli strains C and D) were different from the original strains C and D. Evident degeneration took place in these new strains such as decrease in the productive power of acids, kojic acid, pigments, and the aroma and the reduction of vesicles. Particularly the properties of the new strains were rather similar to those of the strain D and it seemed that also the three kinds of sake were commonly alike to the sake brewed with the strain D in the previousyear.

Milk Lipase System. II. Comparison of Solvent Extraction and Churning Methods for Obtaining Fat from Milk for Free Fatty Acid Measurement

Summary A method for the removal of fat from milk products which involves the use of ethanol, ethyl ether and Skellysolve F was developed. The application of this solvent extraction method to rancid milk yielded fat averaging 30 per cent higher in acidity than fat obtained by churning and resulted in better recovery of the fat. The solvent method is adapted particularly to the removal of fat from homogenized products of low fat content, thereby eliminating the loss of water-soluble fatty acids through separation. Moreover, the addition of lactic acid and/or formalin to cream had little effect upon the acidity of the fat resulting from solvent extraction, but increased appreciably the acidity of that obtained by the churning process. The solvent method was superior to the churning method for recovery of pure fatty acids from cream, particularly the lower acids, butyric and caproic. This is emphasized by the fact that many samples of fat which were solvent-extracted from milk exhibited a rancid flavor, whereas churned fat from the same source did not. However, even with the solvent method, butyric acid recovery was low as determined by titration. Improved recovery of butyric acid added to cream resulted when the temperature and pressure of solvent removal from fat was lowered from 100° C. and 500 mm. mercury to 60° C. and 20 mm. mercury. However, when rancid cream was extracted, these modifications proved to be of questionable value so far as fat titration values were concerned, due to the small amounts of volatile, water-soluble fatty acids present. Chemical analysis failed to show any appreciable differences, other than in acid degree, between solvent-extracted and churned fat, whether the fat was from normal or rancid milk. Also, analysis of the ethanolic soluble and insoluble fractions of solvent-extracted fat failed to indicate definitely selective hydrolysis by milk lipase. The data presented in this study indicate the need for re-evaluation of results from lipase studies which are based upon the titration of fat obtained by churning methods.

チェダー・チーズの製造試驗 (第1報)

It was begun to make this study, with the object of determining the scientific and sine method of making Chedder cheese of the best quality.In this study Chedder cheese of British type was made.In order to omit the ripening period, a proper quantity of lactic acid was directly abdded to raw milk after the addition of starter. In this way the acidity of the milk was adjusted to 0.20-0.22% as lactic acid, and then rennet was added.After curing for about 61/2 months, cheeses were chemically analysed and tested as to the flavor, texture and body.From the results thus obtained, the following were made clear.(1) In case of Chedder cheese of British type, sour taste is a little stronger, but the development of bitter taste and gas holes is generally reduced and it is easy to make cheese of firm body and clok texture.(2) The addition of lactic acid to raw milk has rather good effect on the quality of cheese and shortens the manufacturing time by omitting the ripening period of raw milk.(3) The most important points during the cheese-making process are cutting, dipping and milling (the end of cheddaring); especially the acidities of the whey at these points have a great influence on the quality of cheese and these acidities in case of the cheese of the best quality were respectively 0.147%, 0.185% and 0.588% on an average.(4) Cheese should contain as little water as possible within the limits of not becoming mealy and the average water-content of the cheese of the best quality was 36.17%.

A simple, inexpensive stock formula for young infants

" F H E artificial feeding of young infants did not become a science unJ t t i l the beginning of the twentieth century when the Paris obstetrician, Pierre Budin, said: " I n sterilized milk alone is safety and it must be the basis of all artificial feeding. The purest of milks, the sterile supply which flows from the mother's breast, given in excess, may cause fatal digestive troubles." His law, based on many years of clinical observation, states that there is danger in feeding more milk in twenty-four hours than the equivalent of one-tenth of the infant's body weight. For the first third of the century most of the artificially fed infants of France have been fed small, increasing quantities of undiluted, sterile milk. Early in the century Heubner, Germany's first pediatrician, proved by means of the calorimeter, that the young infant requires approximately 100 calories per kilogram of body weight (about 45 calories per pound) in twenty-four hours. His one-third, one-half and twothirds milk dilutions, enriched with lactose before sterilization, have retained their popularity for over a fourth of a century in many European countries. He stressed the danger of feeding more carbohydrate in twenty-four hours than the equivalent of one one-hundredth of the infant 's body weight. During the second decade, summer diarrhea with a high infant death rate from alimentary intoxication continued among artificially fed infants throughout Europe and America. Czerny and Keller put their faith in buttermilk, boiled with flour and sugar; Finkelstein and Meyer perfected Eiweiss-milch (protein milk); Soxhlet convinced the pediatric world that the combination of dextrin and maltose (Niihrzucker) could be fed in larger amounts than could lactose, without provoking fermentation and diarrhea. Roteh's percentage method gained adherents in our Eastern States, but proved to be no panacea. By 1912 dextrimaltose had already replaced Niihrzueker as the American carbohydrate of choice. A few years later Marriott found that the addition of lactic acid to sterilized cow's milk dilutions permitted the feeding of higher concentrations of milk and corn syrup. His formulas quickly gained in popularity and are today extensively used in the feeding of well and nutritionally disturbed infants.

I. Influence of Lactic Acid on Unicellular Organisms.

It is well known that malignant tumors produce a greater amount of lactic acid than the large majority of normal tissues. It appeared to us, therefore, of interest to study the effect of lactic acid on the proliferative activity of different kinds of cells and organisms. We undertook experiments on the influence of lactic acid on the growth of paramecia, yeast, rats, and malignant tumors. We neutralized the C.P. market preparation of lactic acid with sodium hydroxide until the different pH's desired were obtained. Lactic acid solutions were prepared varying between pH 3 and pH 7. In each experiment distilled water acidified with so much hydrochloric acid that the same pH was obtained as in the lactic acid solution was used as control. In our experiments with paramecia we found that pure lactic acid is very toxic because of its strong hydrogen ion concentration. In a solution of lactic acid 1:5,000 the paramecia died within a few minutes, and even when the solution was weakened to 1:10,000 a high mortality of the paramecia was noted. Lactic acid in the concentration of 1:1,000 neutralized with sodium hydroxide to pH 7 kills the paramecia within one or 2 days. Weaker solutions of lactic acid such as 1:5,000 at pH 7 begin to inhibit the multiplication of paramecia after some time, and kill these organisms after from 5 to 7 days. This can be seen in the following table. This table shows one of our many experiments in which we compared the rate of multiplication in paramecia in hay extract alone (control) and in the same kind of hay extract after the addition of lactic acid in a concentration of 1:5,000. In each experiment we used 8 watch glasses, 4 of which served as controls, and 4 of which contained lactic acid.

THE EFFECT OF VARIOUS REAGENTS ON STUFF IN THE BEATING.

The author has studied the effects on stuffs of various reagents and of the preliminary treatments when beaten under definite conditions in the ball mill, and has obtained the following results : 1. When treated preliminary with dilute solutions of strong acids under proper conditions the wet beating of certain pulps is rapidly attained due to a reduction of the aggregation degree of the cellulose. But the loss of minute fibres or the so-called slime from the wire cloth increases and, moreover, the strength of paper sheets from them is greatly reduced. Using dilute acid solutions as beating media, no difference is found in the beating degree comparing with the case of pure water.2. Weakly xanthated pulps give very wet stuffs by beating but the latters become very free when decomposed with an acid. The pulps once weakly xanthated and then decomposed with an acid are hard to be wet beaten.3. The addition of alcohol or glycerin to the water retards beating.4. The pulps treated preliminary with conc. zinc chloride solutions give very free stuffs the absorbent power of the sheets produced being very great.5. Beating in alkaline solutions results also free stuffs. The pulps treated preliminary with conc. alkaline solutions are hard to be wet beaten.6. Kraft pulps, when bleached, become soft and are easy to be wet beaten. The effects of breaching on sulphite pulps are not definite depending on the degree of bleaching.7. The addition of lactic acid to the water or the preliminary steeping of pulps in dilute lactic acid solutions does not accelerate beating which being against the claim in C.G. Schwalbe's D.R.P. 379996.8. Pulps for artificial silk show no special properties compared with ordinary paper pulps in their beating behaviours. Purified pulps for nitrocellulose are hard to be wet beaten.

Behaviour of Diphtheria Bacilli in Acidified Media, especially with reference to Virulence Tests

1. The growth of diphtheria bacilli in suger-free pure casein digest broth may be accelerated by the addition of dilute nitric, acetic and lactic acids, and delayed by certain monobasic fatty acids.2. The limiting acid zone for toxic and non-toxic varieties is unaffected by initial dilute acidifications by several acids, but incresaed by the addition of citric acid.3. The time periods and intensity of the reaction changes produced by diphtheria bacilli growing in a sugar-free casein digest medium are altered by the addition of certain acids. Toxic strains produce earlier and more progressive alkalinity when dilute acetic or nitric acid is included in the medium: and later and lessened alkalinity in the presence of butyric, formic, and propionic acids. Certain other typical acids do not exert any obvious action. Non-toxic strains are less affected by the selected acids, although butyric acid generally retards reaction changes.4. The time required for virulence testing is decreased, and the potency of the bacillus under examination is more evident when 1/200 η acetic or nitric acid is added to the culture medium. Acidified casein digest plus peptone broth yields practically the same results as acidified fermented veal peptone infusion. The acidification does not affect the metabolism of non-toxic strains.5. The disadvantages of unfermented meat infusions and the ascribed harmful effects of the fermentation products in fermented meat broths, may perhaps be avoided by the substitution of casein digest peptone medium. The advantages of the starting action of the glucose may be retained by adding acetic or nitric acid to the casein digest.6. Individual strains of diphtheria bacilli differ considerably in their capacity of altering the reaction of culture media, and in their toxic potency. It does not seem permissible to apply to newly isolated organisms all the published results obtained from cultures that have been repeatedly subcultured and established as toxin producers in nutrient bouillon. As a presumptive test in the virulence testing of bacilli just transferred from human tissues to artificial culture media the tendency of non-toxic strains to produce early formation of alkali in adequately buffered and adjusted unfermented veal broth may be thought worthy of extended trial.