bluuebunny/crossref_metadata_2025 huggingface dataset:
80. An Investigation of Kuban Fermented Milk
Authors: Bogdanoff V. M.
Published: June 2009

1. Kuban fermented milk is characterised by two types of fermentation, i.e. lactic acid fermentation and alcoholic fermentation.

2. The micro-flora of such milk always embrace the following components: (a) a lactic acid producing streptococcus resembling Str. hollandicus; (b) a lactic acid producing rod of the type of L. bulgaricus; and (c) three types of yeast.

3. There is close symbiosis between the component organisms. The two lactic acid producing organisms can function normally in the absence of the yeasts. The latter, however, prolong the vitality of the starter and also impart a specific taste to the fermented milk.

4. Inoculation of the natural starter with Str. lactis results in a rapid multiplication of this organism and an over-production of acid, which imparts to the fermented milk the taste of ordinary sour milk. A similar undesirable taste is produced if the fermented product is prepared from raw, instead of heated, milk.
96. The Neutralisation of Cream for Butter-making
Authors: Wiley W. J.
Published: June 2009

The reactions which occur when sour cream is “neutralised” with calcium hydroxide and sodium bicarbonate are discussed from the point of view of the acid-base equilibria.

Experimental results are recorded showing that:

1. When lime is the neutraliser, pasteurisation has little effect on the pH. or titratable acidity of the neutralised cream.

2. The reduction in acidity when lime is used is shown to vary from that calculated from the sodium hydroxide titration to an extent which depends on the pH of the neutralised cream. The reasons for and extent of this variation are defined.

3. When sodium bicarbonate is used as a neutraliser the loss of carbon dioxide (which is influenced by the method of pasteurisation adopted) has most influence on the degree of neutralisation obtained and the experiments show the extent of this at various acidities.

The variations in the pH-titratable acidity relationship of creams neutralised with calcium hydroxide and sodium bicarbonate are defined.
97. A Study of Progress of Lactation in Relation to the Milk Yield and the Butterfat Percentage of Milk Produced by Cows of Shorthorn Type
Authors: Oxley C. D.
Published: June 2009

1. The mean and the standard error of the mean of milk yield and of butterfat percentage have been determined for each of the first five successive Milk Recording Society tests of both afternoon and morning milk.

2. The yield of butterfat and the coefficient of correlation of milk yield and butterfat percentage at each test have been calculated.
104. Studies in Cheddar Cheese. IV. Observations on the Lactic Acid Flora of Cheddar Cheese made from Clean Milk
Authors: Davis John Gilbert
Published: June 2009

1. The lactic acid flora of Cheddar cheese made from milk of certified quality form a well-defined, physiologically homogeneous group of bacteria, growing best over a temperature range of from 22 to 37° C. They may be classified into four well-defined types, Str. lactis, Str. cremoris, Sbm. plantarum and Sbm. casei, and have been studied over a period of five years. It appears from the evidence found that Str. lactis and Str. cremoris are distinct species, but that Sbm. casei and Sbm. plantarum represent different stages in the adaptation of a common progenitor to conditions in a ripening cheese. Both the streptococci and the streptobacteria appear to be unable to oxidise sugars and may thus be considered indifferent to molecular oxygen.

2. A study of their frequency distribution from the curd at making to an 18 months old cheese has shown that Str. lactis and Str. cremoris are equally viable during the first month, after which the rod forms begin to predominate, Sbm. plantarum and, later, Sbm. casei being found. The former lactobacillus is only found when the cheese is from 1 to 5 months old, the flora consisting entirely of Sbm. casei after this time. The general vigour of all strains decreases with increasing age of the cheese. There is a marked correlation between the shape of the cell, the viability of the organism in cheese and its resistance to acids and lactates.

3. The factors controlling the sequence of flora in Cheddar cheese are discussed. There is no evidence that titratable acidity, oxygen tension and differential carbon sources are responsible for the sequence. It is suggested that lactate concentration, the extent of protein degradation and osmotic pressure are factors responsible for the gradual replacement of the streptococci by the rod forms.

4. The significance of sugar fermentations by the lactic 'acid bacteria studied is discussed. The slow production of lactase is shown to be the reason for the slow growth of weakened strains in litmus milk.

5. Str. cremoris predominates over Str. lactis in the depth of the cheese in the early stages of ripening, whereas near the surface the reverse holds. Certain strains of Str. cremoris isolated from the depth of the cheese were particularly vigorous in growth in litmus milk, forming gas and beginning to peptonise the milk in about 3 days. Such strains consisted of very long chains of large cells of peculiar morphology. It is suggested that this finding is related to the known greater rate of ripening in the depth of the cheese.
117. An Unusual Variation in the Butterfat Content of Milk
Authors: Hartley K. , Baker D. W. H.
Published: June 2009

1. Some account has been given of the cattle kept on the Government Farm at Samaru, Zaria, and of their management in the wet and dry seasons.

2. Figures extending over four seasons have been presented to show thatthe butterfat content of the milk produced on this farm is consistently higher in the morning than in the evening during the wet season, and that the reverseis true during the dry season.

3. The relative quantity of milk produced in the evening during the dry season is slightly less than during the wet season, but this difference is quiteinadequate to explain the change in the percentages of butterfat.

4. Some evidence is offered that this change in butterfat content is directly due to the marked climatic differences between the two seasons, and that it cannot be controlled by altering the diet of the cattle.
125. Technique for obtaining Anaerobic Milk, with some Observations on its CO2Content
Authors: Jackson Christopher James
Published: June 2009

1. A method has been described for obtaining milk anaerobically from the udder.

2. A technique for transferring anaerobically drawn milk to an electrode vessel for the determination of oxidation-reduction potentials under anaerobic conditions has been described.

3. A technique for transferring anaerobically drawn milk to a van Slyke apparatus for gas analysis has been described.

4. The total CO2of cows’ milk is about half that of their blood plasma.
129. The Chlorine Content of Milk as an Indication of Mastitis
Authors: Blood J. W. , Rowlands A.
Published: June 2009

1. The importance of a rapid and simple test for the diagnosis of mastitis in cows is a question which has attracted considerable attention on the part of many workers. One such test based on the determination of chlorine in milk by a rapid method has been advocated recently by Rosell.

2. The authors of this paper have made a careful examination of this method and compared the results obtained on samples of milk with those given by other methods known to yield reliable and reasonably accurate results.

3. The direct titration of chlorine in milk with silver nitrate solution, without the removal of proteins, invariably gives high results, and, moreover, a satisfactory end-point is difficult to obtain.
149. The coagulation of milk with rennet. Some experiments with slow-renneting and soft-curd milks
Authors: McDowall F. H. , Dolby R. M. , McDowell A. K. R.
Published: June 2009

Apart from mastitis milk there appear to be two types of soft-curd milks:

(1) Milks of individual cows which throughout a lactation or throughout their lives persistently give soft-curd milks. Such milks readily respond to additions of acid and appear to be due to the breed and individuality of the cow and not to any abnormality.

(2) Milks of cows or herds which, though normally giving a satisfactory coagulum, suddenly become rennet-resistant for a certain period. Such milks are more difficult to deal with as in general they do not respond to additions of acid unless these additions are large.

There is little evidence available to show whether the two types are regularly related, but some individual cows in a herd do produce soft curd milk of the type which is unresponsive to the addition of acid regularly throughout a season when the majority of the cows in the herd are giving normal renneting milk. In the work described above on individual cow's milk there has been no attempt to classify the milks according to the effect of acid on the coagulation, although it is now realized that such a course would have been desirable.
171. The effect of commercial sterilization on the nutritive value of milk. IIa. biological value and digestibility of the proteins (nitrogen) of milk
Authors: Henry K. M. , Kon S. K.
Published: June 2009

1. The biological values and true digestibilities of the proteins of raw and commercially sterilized milks from the same bulk have been compared on rats by the method of Mitchell.

2. For raw milk a biological value of 84·3 and a true digestibility of 96·4 were obtained, while the figures for sterilized milk were 79·1 and 95·3 respectively.

3. Statistical tests showed that the difference in true digestibility was not significant but that the lowering of the biological value by about 6% could be ascribed to the effect of the heat treatment, the odds against chance factors being 625: 1.
181. Induced O/R potentials, rates of growth and the volatile acid production of lactic acid bacteria in milk
Authors: Davis J. G.
Published: June 2009

The abilities of type cultures of lactic acid bacteria to reduce five O/R indicators in plain milk and yeast dextrose milk have been described and the factors influencing their behaviour in this respect discussed. Methylene blue, litmus and safranine appear to be of some diagnostic value for the differentiation of types. There is a marked correlation between rapidity of growth in milk, ability to reduce O/R dyes and the proportion of by-products. This relationship holds not only for the different groups and types, but also for variations in behaviour observed in species kept under laboratory observation. It is suggested that rate of growth is fundamentally related to the amount of by-products and hence presumably to flavour-producing substances such as diacety and acetic acid. Thus in cheese-ripening enforced slowness of growth may be as important as the presence of specific types.
197. The composition of the blood and milk of lactating cows during inanition, with a note on an unidentified constituent present in certain samples of abnormal milk
Authors: Smith J. A. B. , Howat G. R. , Ray S. C.
Published: June 2009

1. The yield and composition of the milk secreted during a 12-day fast is recorded. The solids-not-fat, the nitrogen partition, the chloride, lactose, fat and phosphatase contents are discussed.

2. The presence of an unknown substance in the “abnormal” milk obtained from two of the cows is recorded, and it is shown that similar amounts of an unknown constituent must also have existed in the starvation milk analysed in the course of their work by Overman & Wright(i). The nature of this substance has not yet been elucidated.

3. Certain substances in the blood were estimated before, during and after the fast, and the possibility of relating changes in them with corresponding changes in the milk is discussed.
226. The effect of commercial drying and evaporation on the nutritive properties of milk
Authors: Henry K. M. , Houston J. , Kon S. K. , Osborne L. W.
Published: June 2009

1. Spray-dried (Kestner process), roller-dried and evaporated milks were prepared commercially from one batch of raw milk.

2. The biological value of the proteins (nitrogen), vitamin B1and the growth-promoting properties of the milks were measured by tests on rats.

3. Vitamin A and carotene, riboflavin and vitamin C were measured by physical and chemical methods at intervals in the course of storage for a year.

4. No significant difference was found between the biological values of the proteins (nitrogen) of the processed milks. The values ranged from 80 for evaporated milk to 84 for spray-dried milk.

5. The proteins (nitrogen) of evaporated milk were significantly less digestible (true digestibility 91) than those of spray-dried milk (true digestibility 94). The difference between either of those and roller-dried milk (true digestibility 93) was not significant.
232. A simple and accurate viscosimetric form of rennet test
Authors: King C. W. , Melville E. M.
Published: June 2009

1. Some existing types of rennet tests are briefly reviewed.

2. A viscosity type of rennet test is described and results from its use are given.

3. A mathematical treatment of the problems involved is given, which leads on to

4. Construction of graphs showing progressive variation in “Dying away of amplitude”, “Logarithmic decrement” and “Viscosity coefficients” of milk under the action of rennet. Since viscosity determinations on liquids and gases have been commonly carried out with a disk type of viscosimeter, such a type is now introduced and similar graphs constructed from observations during its use. A close similarity in graphs to those furnished by the cylinder type of viscosimeter is obtained. The cylinder type of apparatus, we find, is more convenient in use with milk in reference to rennet action.

5. Arising from the graphs a more precise method of terminating a rennet test with the present type of apparatus is indicated.
245. The partition of serum calcium about the time of parturition in the dairy cow
Authors: Duckworth J. , Godden W.
Published: June 2009

Data have been given of the variations in the calcium ion, ultrafiltrable calcium complex, non-ultrafiltrable calcium complex and protein-bound calcium at normal parturition in the dairy cow, and an interpretation of the results has been presented. The variations observed have been shown to be consistent for all the animals studied.

Serum phosphatase did not show any consistent changes at the time of parturition.
254. The determination of pH in milk and whey by means of colour indicator paper
Authors: Seekles L.
Published: June 2009

Lyphan paper M 25 can be used for pH measurements in milk and whey in the pK range 5·4—6·6. As a rule the error does not exceed 0·1 pH.

In very acid milk and whey (pH < 5·4) lyphan paper of the L series may be used. Generally the deviation does not exceed -0·2 pH. In alkaline milk and whey lyphan paper cannot be used.

In milk and whey from cows infected with mastitis M 25 may be used unless the pH exceeds 7.
270. Lancefield group B streptococci (Str. agalactiae) on the hands of milkers and others
Authors: Harrison J.
Published: June 2009

Lancefield Group B streptococci have been recovered from the hands of milkers even in herds where infection was very light. Since these organisms had the biochemical reactions of Str. agalactiae, and since none were recovered from the hands of non-milkers, it is considered that they were identical with this organism and that the milkers' hands are a potential source of danger to cows. The methods of disinfection at present in use have been criticized and suggestions for improvements made.
272. “Slowness” in cheesemaking
Authors: Harrison J. , Dearden D. V.
Published: June 2009

Two cases of “slowness” in cheesemaking are reported in which the trouble was eliminated by changing the source of the starter.

Attempts to isolate either bacteriophage or “non-acid” organisms failed.

Abnormal milk had no effect on the rates of acid production when compared with control normal milk.

A fall in the acidity of the whey draining from the cooler was observed.

The inability of certain strains of streptococci to grow at scalding temperatures appears to be one cause of “slowness” in cheesemaking.
278. Studies on ass's milk: Composition
Authors: Anantakrishnan C. P.
Published: June 2009

The total solids of samples of ass's milk ranged from 7·80 to 9·10, the solids-not-fat from 7·14 to 8·50, and the fat from 0·54 to 0·71%.

The nitrogen distribution in ass's milk is: casein 39·5, albumin 35·0, globulin 2·7 and non-protein nitrogen 22·8% of the total nitrogen. Ass's milk contains: casein 0·70, albumin 0·62 and globulin 0·07%. The total protein content is 1·39%. Ass's milk is therefore characterized by a low casein, a low globulin and a high albumin content.

The non-protein nitrogen consists of amino nitrogen 8·1, urea nitrogen 24·3 and uric acid 0·7 mg./100 ml. of milk. The urea content is twice that present in cow's milk.

The mean chloride and lactose contents of the milk samples are 0·037 and 6·1% respectively.

The average calcium and phosphorus content of ass's milk are 0·081 and 0·059% respectively. Half the calcium is ionic, and half is in colloidal form.

The phosphorus distribution is: total acid soluble 84·0, acid soluble organic 38·5, easily hydrolysable ester 27·4, inorganic 46·0, and colloidal inorganic 23·0 % of the total phosphorus. The ratio of CaO: P2O5is 1:1. 46 % of the total phosphorus is in ester form; this is high when compared with only 12 % in cow's milk; most of the phosphoric ester forms soluble barium salts, which is a distinguishing feature of ass's milk.

The total sulphur content is 15·8 mg./100 ml.

The fat has a penetrating odour and is coloured orange-yellow. It has an iodine value of about 86, which is much higher than that for human milk fat. The Reichert (9·5) and Kirschner values (5·7) are low.

In general, the composition of ass's milk resembles that of human rather than of cow's milk.
280. The relationship of methods of bacteriological examination to the eradication and control of mastitis (Streptococcus agalactiae): I. The use of an enrichment technique in revealing streptococcal infections of the cow's udder: II.Streptococcus agalactiaeinfection in heifers
Authors: Mattick A. T. R. , Shattock P. M. F. , Jacob M. Moreira
Published: June 2009

In the course of attempts on a field scale to eradicate or controlStr. agalactiaeinfections, comparisons of the efficiency of several bacteriological methods have been made. It has been found that by using a method of enrichment, many cases of infection with small numbers ofStr. agalactiaecan be demonstrated in animals which give negative results by other methods. The frequency of examination has been shown to have an important influence upon the number of positive cases discovered.

Light infections have been, proved to persist for long periods. Light infections withStr. dysgalactiaeandStr. uberishave also been found in many cases.Str. agalactiaehas been shown to be present in no less than 21 % of animals in their first lactation and 4·5 % of heifers were found to harbour this organism whilst in isolation before joining the herd. The bearing of these findings on the theory of contagion inStr. agalactiaeinfections has been discussed.
297. The firmness of rennet curd; its measurement and variations
Authors: Rowland S. J. , Soulides D.
Published: June 2009

A method is described for the measurement of the firmness of the rennet curd from 100 ml. samples of milk coagulated under conditions simulating those of the cheesemaking process. Tests with a series of homogeneous curds ranging in firmness from very soft to very hard showed that the curds behaved as elastic gels of varying modulus, and the deformation produced under a suitable compressive load was accordingly adopted as a simple objective measure of firmness.

The method was used to observe the variation in the curd firmness of samples of milk from individual cows and separate quarters, with some observations on the relationship between curd firmness and milk composition, and the effect on curd firmness of variations in the following factors: acidity, addition of calcium chloride, amount of rennet, time of coagulation, and the admixture of soft-curd milk.

The results of these experiments indicate that the method provides a satisfactory measure of the rennet curd firmness of small samples of milk. The utility and applications of the method are discussed, and the suggestion is made that a standardized reproducible test on the same principle should be evolved to serve the same function with regard to milk for cheese making as the standardized measurement of curd tension serves with regard to the digestibility and suitability of milk for infant feeding.
298. The occurrence of slow-reducing coliform organisms in milk
Authors: Morris C. S.
Published: June 2009

Milk samples may frequently contain coliform organisms which give very slow reduction of methylene blue at 37° C.

This slow reduction seems to be due to two factors present in raw milk, both of which are destroyed by heating milk to 70° C. for 1 hr. These factors are (a) a specific bactericidal substance, and (b) a growth-inhibitory factor.

All the cultures examined appeared from differential tests to be intermediate types of coliform organisms. All were citrate negative and failed to produce acid or gas when grown in MacConkey's broth at 44° C. This tends to confirm the findings of Taylor (4) that the use of certain tests for the differentiation of coliform bacteria is not justified.
303. The production of rennet from living calves
Authors: Berridge N. J. , Davis J. G. , Kon P. M. , Kon S. K. , Spratling F. R.
Published: June 2009

Abomasal juice containing rennin was obtained from living calves by means of an abomasal fistula as described by Fomin, in order to ascertain whether the process could be used as an alternative method of manufacturing rennet, should the present curtailed sources fail completely.

The operation for fistula was performed on the calves at the age of about a fortnight by the technique of Phillipson & Innes. The animals received, during the three months for which the experiment lasted, an exclusive diet of whole milk, supplemented by minerals and vitamin D. Although only two calves were used, we feel that the results are nevertheless representative.

Abomasal juice was obtained by allowing them to drink diluted whey and removing it through the fistula after about half an hour. The mean yield of rennin for each ‘perfusion’ from the first calf was 3120 units with a standard deviation of ± 1330. The corresponding figures for the second calf were 5680 and ± 2560 respectively. (One unit of rennin clots 10 ml. of substrate in 100 sec. The substrate is made by dissolving 12 g. spray-dried skim-milk powder in 100 ml.N/50 calcium chloride solution.)
310. The influence of ‘abnormal’ milk upon the yield and quality of Cheddar cheese
Authors: Johns C. K. , Gibson C. A.
Published: June 2009

In studies previously reported (1) it was found that milk of normal appearance from cows having a latent infection with Streptococcus agalactiae yielded less cheese than that from cows with normal udders. Milk from cows free from Str. agalactiae infection, yet classed as ‘abnormal’ on the basis of biochemical tests, behaved similarly. The lower yield appeared to result from the lower casein and solids-not-fat contents of these ‘mastitis’ milks. With a single exception, the quality of the cheese made from these milks was not inferior to that of cheese made from normal milks. These findings appeared to warrant the extension of the studies to ordinary cheese-factory milks.
315. The effects of commercial processing and of storage on some nutritive properties of milk. Comparison of full-cream sweetened condensed milk and of evaporated milk with the original raw milk
Authors: Henry Kathleen M. , Houston J. , Kon S. K. , Thompson S. Y.
Published: June 2009

1. Full-cream unsweetened condensed milk (evaporated milk) and full-cream sweetened condensed milk (condensed milk) were prepared simultaneously on several occasions each time from a common bulk of raw milk. Heat treatment in the preparation of evaporated milk is, of course, much more severe than with condensed milk.

(a) There was no loss of vitamin A, carotene or riboflavin in either of the processes.

(b) The mean loss of vitamin C as compared with the raw milk was 10% for condensed and 60% for evaporated milk.

(c) The vitamin B1losses were 3·5 and 27% respectively.

(d) Tests on rats showed that the biological values and true digestibilities of the proteins of the raw, condensed and evaporated milks were respectively 85·6 and 94·2, 84·6 and 98·8, 84·1 and 93·7. The differences in biological value are without statistical significance but the digestibility of the condensed milk was significantly higher than that of the other two milks.
348. Some modifications of the Schibsted fat aldehyde test
Authors: Mummery W. R.
Published: June 2009

The application of the Schibsted fat aldehyde test for the routine examination of butter and butterfat is facilitated by the following modifications:

(1) Storage of the reagent at cool temperatures.

(2) Use of sodium metabisulphite instead of sulphur dioxide.

(3) Preparation of the standard colour at a lower pH
352. Variations in the carotene and vitamin A contents of certain New Zealand butterfats
Authors: Barnicoat C. R.
Published: June 2009

1. Chemical estimations of carotene and vitamin A in New Zealand butters from two of the principal butter-making districts of the North Island during the seasons 1935–6 show that the total vitamin A potency was fairly high.

2. There were seasonal variations apparently due to nutritional rather than physiological causes. The minimum values (33–37 i.u./g. butterfat) for total vitamin A were found in late summer (February) at the time when the pasture normally tends to dry up, while the peak values (42–53 i.u./g. butterfat) occurred in late winter and spring (July-October). The variations in vitamin A potency with season were in the opposite direction to the variations recorded in the literature for Europe and America. The difference is no doubt due to the practice of stall-feeding in these countries in contrast with the all-the-year-round grazing commonly practised on dairy farms in New Zealand. The spring flush of grass is also later in the season in Europe than in New Zealand.

3. The more deeply-coloured Jersey butterfat was only slightly richer in total vitamin A potency than Friesian butterfat.

4. Contents of carotene and vitamin A in the fat of colostrum were very high, but reached normal values within 4 or 5 days after parturition.
366. Dye-Reduction tests in the bacteriological examination of dried milk
Authors: Higginbottom Constance
Published: June 2009

1. Over 100 samples of roller-dried full-cream milk and rather less than 100 samples of spray-dried milk reconstituted and incubated for 20 hr. at 55, 37, 39, 22 and 15·5° C. have been examined by the methylene-blue or resazurin-reduction tests at 37° C. The results have been compared with the plate count at 37 or 30° C. of the freshly reconstituted milk and with the keeping quality at 15·5° C.

2. A range of reduction times suitable for routine use was obtained after incubation at 22° C., but the results showed a very poor correlation with plate count at 37 or 30° C. and with keeping quality.

3. After incubation at 55, 37 and 30° C. the reduction times were too short, often showed delayed end-points, and the milk frequently clotted during examination.

4. Results with resazurin were similar to those using methylene blue and no significant differences resulted from the two different methods of reconstitution.
372. Control of the moisture content and ‘body-firmness’ of cheddar cheese
Authors: Whitehead H. R.
Published: June 2009

Cheesemaking experiments were carried out to investigate the moisture-retaining characteristics of curd made from milks of varying fat and casein content. The results indicate:

(a) That milk fat helps to retain moisture in a cheese curd. The higher the proportion of fat present the more drastic the treatment required in the cheese vat to reduce the moisture content of the finished cheese to the desired level. A higher cooking temperature, more dry-stirring of the curd and a larger proportion of salt are all necessary with rise in fat content of the curd.

(b) That curd formed from milk of a low-casein content (from Friesian cows) retains moisture in the cheesemaking process more tenaciously than curd from milk of a highcasein content (from Jersey cows).
389. The composition of the milk of Egyptian cows and buffaloes
Authors: El-Sokkary A. M. , Hassan H. A.
Published: June 2009

The milk of 100 cows and of the same number of buffaloes, in Cairo and its neighbourhood, was analysed; analyses were also made on bulk samples taken at 2-week intervals from the milk of the two buffalo and cow herds of the Faculty of Agriculture at Giza. All samples were mixtures of morning and evening milkings in proportion to yield.
399. The estimation of vitamin A in butter: A critical study of methods
Authors: McDowell A. K. R.
Published: June 2009

1. The Lovibond Tintometer has been found more reliable than either the Pulfrich Photometer or the Spekker Absorptiometer for the assessment of the blue colour from the Carr-Price test on butterfat unsaponifiable residues.

2. Using a Beckman Spectrophotometer, vitamin A in butterfat unsaponifiable residues has been estimated also by the intensity of absorption at 325 mµ. From spectrophotometric readings at this wavelength and at 450 mµ, the irrelevant absorption, due both to carotenoid and non-carotenoid compounds, may be calculated as follows:

Corrected density reading at 325 mµ = 9/10 (A – 12/100B),

where A = density reading of the unsaponifiable residue in petrol ether at 325 mµ, B = density reading of the same solution at 450 mµ.

3. The Morton & Stubbs equation for irrelevant absorption in fish-liver oils is not generally applicable to butterfat unsaponifiable residues.

4. A comparison of the vitamin A content of butterfat samples by the Carr-Price test and by the direct spectrophotometric method has shown a reasonably good agreement between the two values.
406. The sale of veal calves and veal production in West Wales (1943–6)
Authors: Phillips R.
Published: June 2009

The volume and seasonality of veal production in west Wales has been obtained from an analysis of the records of the collecting centres of the Ministry of Food.

It has been found that about 1000 tons of veal are produced annually from 55% of the calves sold to the Ministry at an average carcass weight of 56 lb. Most of the veal is produced in the season of the maximum number of calvings, i.e. spring in the eastern areas and autumn in the western areas. Higher average carcass weights are produced in summer and a higher proportion of the calves offered, are veals during the summer than during the winter. March might be taken as the month of maximum veal output but of lowest average individual carcass weights. The relation between veal weights, production and the average price of milk has been illustrated, and the conclusion drawn is that when milk is cheap (summer) veal weights are high. The more intensive the dairying (in the central part of the region) the lower the average carcass weight and vice versa for the less intensively dairying areas. Calves sold for rearing are only of minor significance in the calf trade in west Wales, but one consolation is that the incidence of the casualty calf is also slight. The choice of colour in calves purchased for further rearing supports the general opinion that during the period under review (1943–6) the Shorthorn breed was the most important, and its Hereford crosses the most popular choice in the more remote beefproducing areas of Pembrokeshire.
421. Haemolytic streptococci in cheese
Authors: Hannay C. L. , Newland L. G.
Published: June 2009

In a paper by Mattick & Shattock (1) it is stated that: ‘The suspicion exists in the minds of those who investigated cases of gastro-enteritis that streptococci of the faecal type isolated from suspected cheese may have been responsible for the disease.’ They examined thirty cheeses and found that the faecal types of streptococci were common, and that the haemolytic varieties were rare. Since then the question has arisen as to the identity of the haemolytic streptococci found in cheese examined for the presence of the pathogenic streptococci. While we have never had occasion to examine cheese suspected of harbouring pathogenic organisms, the presence of haemolytic varieties of streptococci, their identity, and their role in cheese œcology is of general interest.
472. Studies in the bacteriology of milk: III. The corynebacteria of milk
Authors: Abd-el-Malek Y. , Gibson T.
Published: June 2009

The corynebacteria that were isolated by non-selective methods from raw and pasteurized milk are of two main types: (1) heat-sensitive diphtheroid organisms which appear to be derived principally from the animal body, and (2) thermoduric saprophytes originating from dairy equipment. The characters of group (2), which are discussed in detail, indicate that all the cultures examined belong to a single species,Corynebacterium lacticum.Reasons are given for classifying that species inCorynebacteriumand for suppressing the genusMicrobacterium.
475. Studies on variations in the solids-not-fat content of milk: V. Variations due to winter feeding practice
Authors: Bailey G. L.
Published: June 2009

During the twelve years from 1935 to 1946 the type of foods given to sixty-one Dairy Shorthorn first calvers during the months of February and March changed so that the dry-matter intake of the cows rose and the dietary fat fell, but there was little change in the Protein and Starch equivalent they received.

Milk yield varied directly with the amount of fat and starch equivalent in the diet and inversely with the dry matter.

The solids-not-fat percentage of milk varied directly with the amount of starch equivalent, and inversely with the dry matter content, of the diet.

The milk-fat percentage was not influenced by the foods given.

It was shown that the fall in the level of solids-not-fat in the milk was largely due to the increase in the dry matter intake of the cows.
494. The milk-ejection response of the sow to standard doses of oxytocic hormone
Authors: Whittlestone W. G.
Published: June 2009

The milk-ejecting activity of the hormones of the posterior-pituitary gland is well known and has been adequately reviewed (1). Most of the published information deals with the lactating dairy cow. In the course of work at this Station involving the lactating sow as a basis for assay of the milk-ejecting hormones (2, 3), data have been collected on the effect of a standard dose of oxytocin. Our normal assay procedure (2) involves giving the animal a preliminary dose of 0·5 unit of oxytocin. Thus over one lactation we have been able to record the time between injection into the ear vein and the onset of milk let-down, and the period during which milk may be obtained by simple hand-milking, for a number of sows. Braude & Mitchell (4) have published figures for the milk let-down effects of doses of oxytocin ranging from 1 to 10 units. The following results were obtained with &5 unit. All sows used were of the Berkshire breed.
495. The effect of prepartum milking on the composition of the prepartum and postpartum secretions of the cow
Authors: Rowland S. J. , Roy J. H. B. , Sears H. J. , Thompson S. Y.
Published: June 2009

Eleven Shorthorn cows were milked for 14 days before their expected calving date. The total amount of prepartum secretion varied, between cows, from 1 to 961.

Determinations of total solids, fat, solids-not-fat, lactose, total protein, ash, calcium, phosphorus, chloride, casein, albumin, globulin, proteose-peptone, N.P.N., vitamin A and carotenoids were made regularly on the secretions of eight of these cows during the prepartum period, and for 4 days postpartum; and, for comparison, on five samples of Short-horn colostrum each representing the total secretion obtained from the two milkings within the first 24 hr. after calving.
500. The so-called ‘nascent’ bacteriophage phenomenon
Authors: Whitehead H. R. , East Anne , McIntosh Lola
Published: June 2009

The apparent lytic effect of a newly formed (‘nascent’) streptococcal bacteriophage on streptococcal strains not normally lysed by the phage was shown to be actually an inhibitory action produced by high concentrations of the phage. The inhibitory effect was exhibited by stock preparations of the phage, used in sufficient concentration, and there was no need to postulate a special potency for the phage in its ‘nascent’ form. The inhibitory effect of phages on heterologous organisms was found to be a widespread phenomenon among strains ofStreptococcus cremorisandStr. lactis. It became apparent only when larger proportions of phage than the traces normally used for lytic tests were employed.
504. Studies on a washed curd variety of cheese: I. The influence of different types of starter
Authors: Whitmore Joan
Published: June 2009

Large-scale manufacture of washed curd cheese has not yet been attempted in Britain. There seems to be no obvious obstacle, and the production of a good washed curd cheese would satisfy several present-day requirements. It is popular with consumers and would be an alternative to the usual standard varieties; it has certain economic advantages in manufacture and excellent properties for retail sale. In addition, low acid whey is in considerable demand as an important ingredient of certain proprietary brands of infant foods; such whey is not readily obtainable by normal cheese-making, but is produced during the manufacture of this cheese.
514. Studies on a washed curd variety of cheese: II. The influence of variation in the washing and scalding processes
Authors: Whitmore Joan
Published: June 2009

1. Eighty-three experimental washed curd cheese were made to investigate the effects of variations in the washing and scalding processes upon the qualities of texture and eyehole formation.

2. Texture was influenced markedly by the amount of washing received by the curd, and a ‘half-wash’ procedure which gave the most satisfactory results is described. Good texture was also favoured by low scalding temperatures (98–107° F.) and short scalding times (8–20 min.).

3. Eyehole formation was affected by scalding time (particularly exceeding 30 min.) rather than temperature.

4. The best combination of conditions appeared to be a ‘half wash’ with scalding at 103° F. for a period not exceeding 25 min.

5. Large cheese moulds (30 lb.) failed to yield a satisfactory product and their use is not recommended.
520. The effect of feeding iodinated casein and L-thyroxine upon the health, reproduction and yield of a dual-purpose breed of cattle and a purely dairy breed
Authors: Aitken J. N. , Boyne A. W. , Crichton J. A.
Published: June 2009

1. Iodinated casein or L-thyroxine, under the conditions of this experiment, had no adverse effect on the general health of a dual purpose (Red Poll) or a dairy breed (Ayrshire) of cattle.

2. The treatment did not increase the total milk or butter-fat production.

3. The treated animals did significantly better than the controls in one lactation only and in the following variables only: (a) daily milk yield adjusted for pre-treatment differences—Red Polls, lact. 1; (b) milk yield for duration of treatment adjusted for pre-treatment differences—Red Polls, lact. 1.
532. The relationship between mastitis and the method of stripping after machine milking
Authors: Neave F. K. , Higgs T. M. , Simpkin D. , Oliver J. , Dodd F. H.
Published: June 2009

At the end of normal machine milking some milk, which cannot be removed unaided even by the most efficient milking machine, remains in the udder sinus. This milk, often some 10% of the total yield depending upon the age of the cow, udder shape, partial vacuum of the milking machine and teat-cup liner design, was formerly most frequently removed by hand. As a result of advice and encouragement farmers are rapidly changing to manipulation of the teat-cups, known as machine stripping. This practice has renewed interestin the old controversy about the effect of the method of stripping on udder health.
534. The cells in bovine milk
Authors: Blackburn P. S. , Macadam Ian
Published: June 2009

Using a differential staining technique, total and differential cell counts were carried out on over 5000 milk samples.

It was found that the cells in both normal and abnormal milk fell into three groups:

(1) Granular leucocytes, including polymorphs, eosinophils and probably basophils.

(2) Lymphocytes.

(3) Epithelial cells (vacuolated and non-vacuolated).

The findings of some earlier workers are discussed.
565. A study of variation in twin cattle: III. Growth
Authors: King J. W. B. , Donald H. P.
Published: June 2009

1. Polynomial coefficients have been fitted to data on growth in live weight to 19 months and on height at withers to 27 months of age shown by one-egg (MZ) and two-egg (DZ) twins and pairs of half-sisters (HZ). The coefficients obtained (a0, a2 and a3) have been subjected to analysis of variance.

2. For growth in live weight, the ratio of intrapair variances for MZ, DZ and HZ pairs was 1:6·8:10 for a1, which gives the straight line best fitting the observed curve. Unrelated pairs, it is calculated, would have had an intrapair variance 20·9 times as great as MZ pairs. From the point of view of minimizing the intrapair variance, the advantage of the MZ pairs was usually a little less for a0, and considerably less for a2 and a3.

3. For height at withers, the results were similar to those for weight.

4. The contribution of environmental variance to total intrapair variance increased from a0 to a3, while that due to additive genetic effects diminished. Owing to the wide fiducial limits applicable, the results can be accommodated assuming only additive genetic effects in addition to environmental effects as estimated from one-egg twins. The extent to which HZ pairs exceeded the variance expected, however, suggests that this simple assumption may prove inadequate.
592. Studies of the secretion of milk of low fat content by cows on diets low in hay and high in concentrates: VI. The effect on the physical and biochemical processes of the reticulo-rumen
Authors: Balch C. C. , Balch D. A. , Bartlett S. , Bartrum M. Patricia , Johnson V. W. , Rowland S. J. , Turner Jill
Published: June 2009

1. Two Shorthorn cows with rumen fistulas were used to investigate the effect of diets high in concentrates and low in hay on the physical and biochemical processes of the reticulo-rumen.

2. During the initial control period of the investigation the cows received daily 16 lb. hay and 20 lb. concentrates (flaked maize 50%, weatings 35%, decorticated ground-nut cake 15%) and during the final control period 18 lb. hay and 10 lb. concentrates. There were three intervening experimental periods, in each of which the cows received 2 lb. hay daily. In the first experimental period they received, in addition to the hay, 24 lb. concentrates; in the second, 20 lb. concentrates and 5 lb. of dried delignified straw pulp in a finely macerated form; and in the third, 20 lb. concentrates. The experiment lasted 27 weeks.

3. In the experimental periods the mean milk-fat percentage remained below 2·0 for 10 weeks, whereas the mean value for the control periods was about 3·5. Addition of the straw pulp to the diet low in hay brought about no recovery in milk-fat percentage. It is calculated that in the two cows the losses in the yield of fat were 62·2 and 51·2% in the first experimental period and 62·5 and 58·7% in the second. In the experimental periods there were increases in the milk solids-not-fat percentage amounting in the two cows to upwards of 0·75 and 0·40 respectively. The composition of the butterfat was influenced by the diets low in hay, the main changes being a marked fall in the Reichert value, and a rise in the iodine value.

4. Digestibility trials showed that in the initial control period and the first and second experimental periods the mean daily intake of digestible crudefibrewas 2·6,0·6 and 3·0 lb. respectively. A tentative estimate of the extent of digestion in the reticulo-rumen, based on the lignin-ratio method, showed that a marked depression in values for the digestibility of the cellulosic constituents of the diet given during the first experimental period took place in the reticulo-rumen. In all experimental periods, even the first, the digestion of starch in the reticulo-rumen was virtually complete, only traces passing undigested to the remainder of the gut. In these three periods the mean daily intake of ether extract remained at 0·4·0·5 lb.
599. The lactose-chloride contribution to the freezing-point depression of milk
Authors: Cole E. R. , Mead M.
Published: June 2009

The contributions of lactose and chloride to the total freezing-point depression of milk have been measured by an incremental procedure. Successive additions of these substances to watered milk have enabled direct determination of the partial freezing-point depression to be made in a medium substantially the same as the original.
611. The steam stripping of taints from liquids: IV. An analysis of continuous counterflow equipment
Authors: Scott J. K.
Published: June 2009

The use of a column to give countercurrent contact of steam and cream to strip taints from the cream is explained. An analysis based on the engineering concept of a transfer unit is presented, and generalized curves are given which can be used for any counterflow column using fresh steam. The generalized curves give the percentage reduction in taint for values of the stripping factor (mV/L) when the number of transfer units is known.

It is further shown that the number of transfer units for any particular design of column depends on the value of the stripping factor. The total resistance to the transfer of taint (HTU)L depends on a liquid-side resistance (HTU)l and a steam-side resistance (HTU)g such that (HTU)L=(HTU)l+L/mV(HTU)g.

Results are given for an experimental column in which the liquid flows as (a) a spray, (b) a falling film or wetted wall. A strong deodorizing effect occurs at the bottom of the column and the resistances to transfer are

Resistances for a full-size plant 3 ft. diameter processing at 10,000 lb./hr. are assessed from the above figures as:

Restriction of the process of taint transfer is controlled largely by the liquid-side resistance. Because the minimum obtainable taint level depends on the liquid-side resistance (no matter how much steam is used) a low liquid-side resistance or a tall column must be used for satisfactory deodorization. A minimum of 4 transfer units is suggested, as this will allow a taint to be reduced to nearly 1·8% of the original value.

A design method is given based on hypothetical taint conditions, the generalized curves, and the characteristics of any proposed counterflow column.