bluuebunny/crossref_metadata_2025_split huggingface dataset:
224. The decomposition of citric acid by Betacoccus cremoris
Authors: Van Beynum J. , Pette J. W. 
Published: June 2009

The fermentation products of Betacoccus cremoris in neutral milk are acetic acid and carbonic acid. In acidified milk or in mixed cultures of this bacterium and lactic acid streptococci the products are acetic acid, C02, diacetyl, acetylmethyl carbinol and 2–3 butylene glycol. The latter three substances may be called “C4 compounds”. Diacetyl is only formed when an oxidation with atmospheric oxygen can take place. Carbinol is found in aerobic and in anaerobic cultures. It may be reduced to butylene glycol. This reduction is more complete at lower acidity, but also depends on the strain of Betacoccus used.All these substances are formed from the citric acid of the milk. However, small amounts of acetic acid may be produced from sugar.From 1 mol. of citric acid are formed: 2 mol. of carbon dioxide, 1–1·5 mol. of acetic acid, 0·5–0 mol. of C4 compounds.A reciprocal relation exists between the quantities of acetic acid and C4 compounds. When the amount of acetic acid is high the C4 compounds content is low. The higher the acidity of the medium in which the betacocci are cultivated the higher is the amount of C4 compounds. This means that the fermentation in neutral media is the extreme case of the fermentation process. Then the production of C4 compounds is minimal (0) and that of acetic acid is maximal (1·5).
276. The drying of cheese whey and of acid casein whey by the roller process
Authors: Waite R. 
Published: June 2009

1. Experiments have been carried out in order to determine the best method of neutralizing cheese whey prior to drying by the roller process. The use of sodium or potassium compounds leads to difficulties in drying and the production of an unpalatable product of poor quality. Neutralization with calcium hydroxide gives a satisfactory product. Over-neutralization must be avoided.2. Complete neutralization of hydrochloric acid casein whey results in the formation of a flocculent precipitate and deterioration in the drying properties; reduction of the acidity from 0·48 to 0·18% by the addition of calcium hydroxide allows successful drying and yields a reasonably satisfactory product. The latter is, however, definitely unpalatable.3. Acetic acid casein whey can be dried without any previous neutralization to yield an excellent and palatable product.
290. The rheology of butter: II. The relation between rate of shear and shearing stress. The effect of temperature and of reworking on hardness and on structural viscosity
Authors: Dolby R. M. 
Published: June 2009

It has been shown that the rate of shear of butter when cut by a wire increases as a power of the load applied to the wire. The values of this power are high (index n = 8 to 15, average 11 at 12.5° C.) and show a high structural viscosity in the butter. There is no indication that butter exhibits a true yield value, but the (rate of shear)/(load) curve is such that a practical yield value is found. The practical yield value (denned as the minimum load required to produce a measurable rate of flow) provides a convenient measure of the hardness of butter. The viscosity of butter decreases rapidly as rate of shear is increased, but the rate of decrease varies from one sample to another. Measurements of spreading capacity should be made at rates of shear comparable with those which occur when butter is spread with a knife.The effect of temperature over the range 6–18° C. on the hardness and structural viscosity of a number of butter samples has been investigated. The effect of reworking has also been studied.
302. Bacteriophages for Streptococcus cremoris Phage development at various temperatures
Authors: Hunter G. J. E. 
Published: June 2009

The effect of temperature on the growth in milk of several strains of Str. cremoris and their appropriate phages has been investigated. The phage races show a wider diversity of reaction to temperature conditions than do the homologous organisms. They frequently have different optimum growth temperatures quite distinct from the optimum growth temperature of the substrate organisms. Some races fail to multiply at 37° C.The implication of the results in cheese-making practice is discussed.
339. The consumption of milk among four social classes of consumers
Authors: Bransby E. R. 
Published: June 2009

1. Data on milk consumption, and other relevant information, were obtained from 150, 152, 124 and 135 lower working, working, lower professional and professional class families respectively in the city of Leeds during May-June 1939.2. An account is given of the factors affecting the consumption of liquid milk at school and at home, and of tinned milk. An estimate is made of the amount of milk consumed by children over and under 5 years of age and by adults, and of the nutritional adequacy of the milk consumption of those three groups.3. An analysis is made of the use of milk in the home and the importance of the three factors: (a) the number of families making milk dishes, (b) the frequency with which the dishes are made, and (c) the amount used in each dish per person per time, in causing differences in the average liquid milk consumption of the four social classes.4. An estimate is made of the extent to which families were obtaining a proper amount of milk, and the number of the families who were not spending sufficient on food to purchase an adequate amount of milk.5. It is concluded that in investigations into the consumption of milk, the various social classes should be studied separately, otherwise fundamental differences between them fail to be disclosed.
349. A simple method of conducting the phosphatase test
Authors: Stiven D. 
Published: June 2009

The value of the phosphatase reaction for controlling the heat treatment of milk is unquestioned, but the accepted method of estimating phosphatase activity, namely, the colorimetric method of Kay using the phenol reagent of Folin, has three disadvantages:(1) The number of estimations that can be performed in a given time is limited.(2) Errors in matching the tints may occur.(3) Samples of milk may be accidentally contaminated with traces of phenol, and this will lead to too high a Lovibond value.
391. The effect of penicillin in milk on the manufacture of Cheddar cheese
Authors: Hunter G. J. E. 
Published: June 2009

Penicillin present in cheese milk affected the performance of various ‘single strain’ starter cultures in the cheese vat.A concentration of 0·07 penicillin unit/ml, in the milk was sufficient to cause a complete failure or ‘dead’ vat with the most sensitive strain of Str. cremoris. Two strains ceased to produce acid in the later stages of the manufacturing process when the milk contained 0·10 unit/ml. With three other strains the 0·10 unit/ml, level delayed acid development; the experimental vats required 20–40 min. longer than the controls to reach ‘salting’ acidity.Flash pasteurization temperatures usually employed in cheese-making (150–160° F.) did not appreciably alter the activity of penicillin in the cheese milk.The quality of the cheese produced was influenced by the rate and extent of acid production by the starter cultures in the vat during manufacture.Experience in the field indicates that where a large number of cows are treated simultaneously for mastitis, there may be sufficient penicillin in the cheese milk to affect the starter, if the milk from quarters undergoing treatment is included in the bulk milk.
407. The number of sweat glands in the helix of the cow's ear and the milk yield
Authors: Findlay J. D. , Goodall A. Myfanwy , Yang S. H. 
Published: June 2009

1. A study has been made of the distribution of the so-called sweat glands in the ears of Ayrshire cattle.2. The number of sweat glands per unit area of skin in the ear was found to vary greatly from one part of the ear to another and did not appear to be related to the milk yield. It is concluded that it is impossible to use the sweat-gland count in the ear as an indication of the milk-producing capacity of Ayrshire cattle.3. The number of sweat glands per unit area in the ear of the very young calf was found to be greater than in the fully grown cow, the number being roughly inversely proportional to the surface area of the ear.4. These findings for Ayrshire cattle are contrary to those published by a number of other workers for cattle of the Red German breed, who claim that any portion of the ear can be used to obtain a sweat-gland count which is closely correlated with milk yield.
535. Reactivation of milk phosphatase following heat treatment. III
Authors: Wright R. C. , Tramer J. 
Published: June 2009

1. Of a number of farm milks examined, two have been found to develop a positive phosphatase reaction following pasteurization at 161° F. in a small H.T.S.T. plant. This phosphatase was not of bacterial origin but was reactivated milk phosphatase.2. Considerable variation in reactivation following pasteurization at 161° F. was found to occur using individual churns of the above farm milk from any one milking. Individual cow samples also showed similar variation when tested by the capillary method. No explanation of this variation is offered.3. Commercial bulk raw milk from road or rail tanks did not develop a positive phosphatase reaction after pasteurization at 161° F. on this plant.4. Cold storage of pasteurized milk susceptible to reactivation results in less reactivation, and some evidence was obtained that cold storage of the corresponding raw milk also results in less reactivation. No such effect has been observed either using the capillary method or with samples of Uperized milk.5. Pasteurizing at 170 and 180° F. usually resulted in increased reactivation as compared with that obtained after pasteurization at 161° F. Shortening the holding time at these two higher temperatures sometimes led to a further increase in reactivation.6. It is shown that no clear relationship exists between the results obtained by plant pasteurization and the capillary method.7. It is suggested that many of the reported cases of pasteurized cream developing a positive phosphatase reaction on storage can be attributed to reactivation of the enzyme.8. Practical implications of reactivation in relation to pasteurized milk are discussed.
537. The composition of sow's milk during the course of lactation
Authors: Perrin Dawn R. 
Published: June 2009

1. The composition has been studied of the milk of forty-four sows in the course of sixty-eight lactations. The milk was obtained by machine milking following intravenous injection of oxytocin.2. Definite lactational trends have been observed for all the major constituents, and the third week seems a critical stage for most of the milk components.3. The mean values for the milk, based on the analyses of over 450 samples from the seventh to fifty-sixth day of the lactation were: fat 9·58 %, protein 6·11 %, lactose 4·62 %, ash 0·92%. Such figures are considered to be rather meaningless for most practical purposes, in view of the marked changes over the course of lactation.4. The day-to-day variation in the composition of sow's milk has been studied. Whereas the fat value changes considerably, the non-fat constituents show a less marked variation. Difficulties in securing a representative sample of the weekly milk have been overcome by preparing a composite sample from three milMngs within the week.5. Some preliminary work has been done on variation in the composition during the process of milking. Sequential samples show an erratic fat content, especially during the early part of the lactation. When calculated on a fat-free basis, the protein, lactose and ash contents are relatively constant during the process of milking.
544. Factors influencing the lactic acid-producing properties of streptococci used in the manufacture of Cheddar cheese: I. Observations relating inhibitory and stimulatory phenomena
Authors: Jago G. R. 
Published: June 2009

1. Many single-strain lactic streptococci used as cheese starters exhibited a difference in susceptibility to an inhibitory substance present in raw and H.T.S.T. pasteurized milk, some being markedly affected whilst others were completely resistant to this inhibitory aubstance.2. The inhibitory effect of raw or partially heated milk on ‘susceptible’ strains of starter streptococci appears to be a widespread phenomenon. It can be said that the inhibitory substance is normally present in all milk supplies throughout the year. It occurs in milk freshly drawn from the udder aseptically.3. Heating the milk to boiling-point for variable periods or autoclaving the milk destroys the inhibitory effect of the milk on ‘susceptible’ cultures.4. The inhibitory substance is closely associated with the fat globules in milk and can exert a marked effect owing to the large surface area exposed.5. Growth-stimulating substances prepared from extracts of fowl liver, separator slime, and yeast were able to overcome the inhibitory effect when added to raw milk. However, the effect of these substances were markedly depressed on the addition of small amounts of freshly separated cream to the cultures.6. It is suggested that the above growth-stimulating substances contain a common growth factor which enters into competition with an inhibitory substance closely associated with the fat globule.7. The inhibitory substance appears to be bacteriostatic in its effect and not bactericidal.8. Owing to the heat lability of the inhibitory substance and its presence in close association with the fat globule, it is suggested that it may be enzymic in nature.
546. Studies on the secretion of milk of low fat content by cows on diets low in hay and high in concentrates: III. The effect of variations in the amount and physical state of the hay and a comparison of the Shorthorn Friesian breeds
Authors: Balch C. C. , Balch D. A. , Bartlett S. , Hosking Zena D. , Johnson V. W. , Rowland S. J. , Turner Jill 
Published: June 2009

1. Four comparable groups of Shorthorn cows were used for an investigation of the effects of various amounts of hay, given with concentrates, on the fat content and yield of milk.2. During the initial and final control periods all the cows received 16 lb. hay daily and about 4 lb. of a balanced concentrate mixture (flaked maize 50%, weatings 35% and decorticated groundnut cake 15%) per 10 lb. of milk produced. During the experimentaltreatment period of 7 weeks the groups received 12, 8 or 4 lb. hay, or 8 lb. coarsely ground hay, per cow daily respectively, with sufficient of a low protein concentrate to compensate for the reduction in hay, and the balanced mixture as in the control periods.3. The change from 16 to 12 lb. hay did not affect the fat content of the milk, a small decline being attributable to the advance in stage of lactation, but the mean values for the last 2 weeks of treatment, adjusted for the differences in the initial control period, showed that the milk fat percentage for the groups receiving 8 and 4 lb. hay and 8 lb. ground hay had fallen by 1·16,1·12 and 1·72 respectively by comparison with that for the 12 lb. hay group.4. A group of Friesian cows was included in the experiment, and received 4 lb. hay during the treatment period. The fall in the fat content of their milk was greater, but not significantly different from, that observed with the corresponding group of Shorthorn cows.5. In the treatment period the milk yields tended to decline more rapidly than in the control periods, and this taken in conjunction with the falls in fat content was reflected in considerable falls in the yield of milk fat, ranging from 28·4 to 55·2% with diets containing less than 12 lb. hay. Both the fat percentage and fat yields recovered in the final control period.
562. The steam stripping of taints from liquids. I. An analysis of processing methods with particular reference to the Vacreator
Authors: Scott J. K. 
Published: June 2009

The operation of equipment for reducing the amounts of volatile taints in liquids by the use of open or generated steam is explained and analysed. From consideration of material balances for each system and the equilibrium characteristics of the volatile substances, formulae and graphical methods are derived and used to show the degree of taint removal which can be attained by the steam. The methods and charts are used to show the performance of Tandem and Triple Vacreators. The methods presented in the paper can be used for any volatile solute but particular reference is made to two substances having equilibrium constants of 17 and 1·4 because these represent a range of volatilities of particular interest and are approximate values for diacetyl and acetoin which can be used as reference substances.The effectiveness of any system is shown to depend on the value of a stripping factor which is equal to the product of the equilibrium constant and the pounds of deodorizing steam per lb. of liquid (i.e. F = mV/L). The efficiency of methods where the liquid is contacted several times with fresh steam is shown to be much greater than for single contact. The gain in efficiency for each stage becomes less pronounced with increasing contacts and the maximum efficiency is shown to be limited even for an infinite number of contacts.
564. The properties of New Zealand butters and butterfats: IV. Refractive index and density of the butterfat
Authors: McDowell A. K. R. 
Published: June 2009

1. The refractive index and density of butterfats were determined for butters forwarded by twenty factories at 8-week intervals over a period of 3 years. The refractive index (n40) ranged from 1·4535 to 1·4571, with mean weighted value of 1·45492. The density (D60) ranged from 0·8885 to 0·8916, with mean weighted value of 0·89045.2. Minimum refractive index results were found in the summer butterfats and maximum results in the winter butterfats, i.e. at opposite seasons to the occurrence of the minimum and maximum in Northern European butterfats. Maximum density results were found in late spring butterfats and minimum results in autumn butterfats.3. The mean monthly results for refractive index and for density of North Island and South Island butterfats showed an appreciable divergence only during the winter months.4. The correlations between refractive index and iodine value, between density and saponification value, and between density and Reichert value, on 140 butterfats sampled over 1 year were all highly significant.
609. Acetone taint in milk due to Bacterium CloacÆ
Authors: Jones G. Elis 
Published: June 2009

In the investigation of an outbreak of acetone taint in bulk milk it was: (a) shown not to be due to the lactating animal; (b) reproduced by the inoculation into milk of a strain of Bact. cloacæ isolated from the tainted milk; (c) shown that seventy other strains of coliaerogenes organisms (including sixteen Bact. cloacæ) did not possess this ability to produce an acetone taint.A search of the literature failed to produce a record of this taint being produced by factors other than acetonemia of the animal.Note. Since writing the article another strain of Bact. cloacæ giving a positive Rothera's test has been isolated at Wye from a sample of milk which developed a typical sickly sweet taint on storage (Billing, E., personal communication, 5. xii. 55).
655. The effect of pH on the extent of splitting or clumping of fat globules caused by agitation of hot cream
Authors: Dolby R. M. 
Published: June 2009

The effect of pH on the extent of splitting and clumping of globules in hot cream agitated by treatment in a Vacreator, by vigorous mechanical stirring or by simple aeration has been investigated. The size distribution of globules was determined in cream before and after treatment either by the microscopic method or by a rapid method involving separation of small and large globules by centrifuging and gravity creaming respectively.It was found that at pH 8 splitting of globules was at a maximum and clumping at a minimum. As the pH of the cream to be treated was lowered towards pH 6, the amount of splitting decreased and clumping increased. The ‘clumping’ of globules in cream during single-stage homogenization was also increased as the pH was lowered.Practical applications of the observations are suggested.The thanks of the author are due to Mr J. A. Singleton, superintendent and Mr B. Le Heron, buttermaker of The Dairy Research Institute (N.Z.) experimental factory, for arranging and carrying out the Vacreator treatment of cream; to Dr F. H. McDowall for helpful advice and criticism, and to Miss R. P. Johnson for assistance with microscopic and analytical work.
680. Some properties of the mammary myoepithelium of the sow
Authors: Whittlestone W. G. 
Published: June 2009

Simultaneous intramammary pressure recordings were made on pectoral and inguinal mammary glands of the sow. Oxytocin was injected via the ear vein and the nature of the pressure curves resulting from quantities of hormone above physiological level studied. The frequency of the periodic contractions of the mammary myopethelium under these conditions was measured and compared with human uterine responses under similar conditions.The writer is indebted to Professor H. McK. Carey of the National Women's Hospital, Auckland for the intrauterine pressure graph shown in Fig. 3. Acknowledgement is also made of the technical assistance given during the experiments by Mr E. D. O'Reilly.
Steam distillation of taints from cream: V. Vapour/liquid equilibrium relationships for some α-diketones in lactose solution
Authors: McDowall F. H. 
Published: June 2009

1. The effect of 4·5% lactose in solution on the vapour/liquid equilibrium relationship for acetylpropionyl, acetyl-iso-butyryl, acetylvaleryl, acetylcaproyl and acetylbenzoyl has been investigated.2. There was no appreciable effect on the relationship for acetylpropionyl and acetylbenzoyl.3. For acetyl-iso-butyryl there was a lowering of the coefficient at low concentration of diketone in the liquid, but at concentrations above 4 p.p.m. there was no appreciable effect.4. For acetylvaleryl at low concentrations in the liquid the coefficient was lowered, and at concentrations above 3·0 p.p.m. in the liquid it was increased.5. For acetylcaproyl the coefficient was lowered by presence of 4·5% lactose in the solution.6. Change in concentration of lactose over the range 0·5—10% had little effect on the vapour/liquid equilibrium coefficient for acetylpropionyl and acetylbenzoyl, but it caused a progressively increased reduction in the coefficient for acetyl-iso-butyryl, acetylvaleryl and acetylcaproyl.
Steam distillation of taints from cream: VIII. Effect of fat content of dairy product on deodorization process
Authors: McDowall F. H. 
Published: June 2009

1. In commercial practice dairy liquids of fat contents ranging from 3 to 90% are subjected to deodorization by steam distillation treatment.2. Increase in fat test of cream causes a rise in the vapour/liquid equilibrium coefficient for tainting substances of low butterfat/skim-milk distribution ratio, and a fall for substances of high-distribution ratio, in cream.3. Increase in fat content of cream reduces the amount of tainting substance in the cream per unit weight of butterfat in the cream, for substances of all butterfat/skim-milk distribution ratios.4. Separation of milk to cream of a high fat content greatly facilitates the elimination of substances of low butterfat/skim-milk distribution ratio from the cream and butter.5. Variation in temperature of separation, by its effect on the distribution ratio for tainting substances, could affect the content of these substances in the final cream, and could possibly cause a change in the character of the cream.6. In the partition of tainting substance between butter and buttermilk in the churning process, fat content of cream affects the proportion of residual taint passing from the treated cream into the butter.7. It is pointed out that, because of the effect of salt in increasing the vapour/liquid equilibrium coefficient of some steam volatile substances, the threshold concentration for a tainting substance in butter can be expected to vary with variation in the rate of salting of the butter.