bluuebunny/crossref_metadata_2025_split huggingface dataset:
725. A comparison of dried skim-milk and white fish meal as protein supplements: III. For fattening pigs fed whey without restriction under commercial conditions
Authors: Braude R. , Mitchell K. G. , Cray A. S. , Franke A. , Sedgwick P. H. 
Published: June 2009

1. An experiment has been carried out under commercial conditions to compare the value of dried skim-milk and white fish meal as protein supplements in a basal meal fed to fattening pigs in conjunction with unrestricted amounts of whey.2. There were four treatments. All pigs received 3 lb./pig/day of a basal meal, reduced to 2 lb. by the 13th week of life, plus unrestricted amounts of whey. The protein supplement in the four basal meals comprising the four treatments were: (1) 10% white fish meal, (2) 10% dried skim-milk, (3) 15% dried skim-milk and (4) 20% dried skim-milk.There were five pens of nine group-fed pigs on each treatment, involving a total of 180 pigs. The pigs were on experiment from approximately 10 weeks of age to bacon weight. Comprehensive carcass measurements were made on all the pigs.3. The results showed that the white fish meal in the basal meal fed with unrestricted amounts of whey could be replaced by dried skim-milk on a weight for weight basis (10%) without adversely affecting the performance of the pigs. Increasing the percentage of dried skim-milk to 15% appeared to have no advantage, but increasing it to 20% resulted in a slightly better performance of the pigs.4. The results are discussed in relation to the findings in previous experiments and it was concluded that the evidence obtained so far strongly suggests that as a protein supplement, dried skim-milk is superior to white fish meal for the fattening pig, when compared on a protein content basis.5. The commercial grading results of the pigs on all four treatments were quite good, with no very marked differences between any of the groups.6. An average daily peak consumption of about 4¾ gal. whey/pig was reached by all groups of pigs during about the 26th–28th weeks of life. The growth curve and pattern of food consumption of the pigs during the experiment were compared with those in two earlier trials carried out under similar conditions, and possible reasons for some of the differences observed were discussed.
729. Characteristics of a presumptive pediococcus occurring in New Zealand Cheddar cheese
Authors: Dacre J. C. 
Published: June 2009

1. Cultural and biochemical details are given of a homofermentative species of lactic acid-producing bacteria, repeatedly isolated from typical maturing New Zealand Cheddar cheese.2. The Gram-positive cocci, occurring mainly in pairs and tetrads in acid media, are greatly stimulated in growth by the presence of yeast or tomato extracts. The organism converts glucose into inactive lactic acid and smaller amounts of acetic acid.3. With the exceptions that the organism does not ferment trehalose and is less tolerant to low pH and high concentrations of Teepol, all its characteristics are similar to those for the genusPediococcus, in particular to the type speciesP. cerevisiaeBalcke.
The estimation of the total solids and solids-not-fat of milk from the density and fat content
Authors: Rowland S. J. , Wagstaff A. W. 
Published: June 2009

The accuracy of the method specified in B.S. 734:1937 for the estimation of the total solids and solids-not-fat contents of milk from the density and fat content has been assessed by direct comparisons with the gravimetric method. A total of 2425 samples of milk, mostly from single herds, were examined in five series over different years.The percentages of solids estimated by the density method were lower, by an average of 0·06, than those determined gravimetrically. To correct for this error, and to compensate for the lower, more accurate fat percentages arising from the recent reduction in the capacity of the Gerber milk pipette, it was proposed that the density formulae be modified to T=0·25D+l·22F+0·72 and S.N.F.=0·25D+0·22F+0·72.These formulae were adopted in October 1957 in an amendment to the B.S. 734 published in 1955.
Making Cheddar cheese on a small scale under controlled bacteriological conditions
Authors: Mabbitt L. A. , Chapman Helen R. , Sharpe M. Elisabeth 
Published: June 2009

A cover for a 40 gal. cheese vat has been specially designed to allow cheese to be made under conditions which prevent the entry of micro-organisms into the vat from the dairy environment. The technique employed is described. Using milk free from lactobacilli it has been possible to make Cheddar cheese in which no lactobacilli grew during the ripening period. An assessment of the role of these and other micro-organisms in cheese ripening should now be possible.The technique should also be of help in other cheese investigations where control of the microflora is desired.
A proposed method for the rapid determination of lactose in separated milk and condensed whey by infra-red absorption
Authors: Goulden J. D. S. 
Published: June 2009

It has been shown that the lactose concentration in separated milk can be determined rapidly with an accuracy of ±1·5% by infra-red absorption methods, using wavelengths in the 10μ region.The method can also be used to determine lactose in condensed whey and should prove applicable to continuous recording techniques.
The effect on milk composition of feeding spring grass to cows
Authors: Waite R. , Castle M. E. , Watson J. N. 
Published: June 2009

1. An experiment to investigate the seasonal increase in the solids-not-fat content of milk, which usually occurs in Britain when cows go from winter feeding to spring grazing, is described.2. Two similar groups of cows were fed good quality winter rations at the same high level both before and after calving (about 115% of the Woodman standard after calving), until spring grass was available. One group of 7 cows was then fed for 6 weeks almost entirely on cut grass, returning to winter rations for a further 3 weeks. The control group of 6 cows continued to be fed throughout the experiment on winter rations and both groups remained indoors for the whole of the experiment. The estimated nutrient intake of both groups in all periods was kept substantially constant.3. Changes in milk yield and composition were mainly those associated with advancing stage of lactation, and grass feeding had little specific effect. It is concluded that the increase in milk protein content which is normally observed soon after the start of spring grazing probably results from an improved plane of nutrition and not specifically from an increase in the intake of soluble carbohydrates.4. Increases in the total nitrogen content of the milk as the experiment proceeded were contributed to uniformly by the casein, total albumin and β-lactoglobulin fractions.
The effect of heat on the vitamin B6 of milk: I. Microbiological tests
Authors: Gregory Margaret E. 
Published: June 2009

1. Four test organisms were used for the microbiological assay of vitamin B6. The test organisms and the forms of vitamin B6 active for them were: Saccharomyces carlsbergensis 4228 (pyridoxine, pyridoxamine and pyridoxal), Streptococcus faecalis R ATCC8043 and Str. faecium Ø51 (pyridoxamine and pyridoxal), and Lactobacillus casei ATCC7469 (pyridoxal).2. By simultaneous assay of the test material with the four organisms the amounts of pyridoxine, pyridoxamine and pyridoxal present were determined. The differential assay technique has been improved by the use of Str. faecium, which is more specific for measuring total pyridoxamine plus pyridoxal, instead of Str. faecalis.3. The optimum conditions for measuring vitamin B6 in milk were studied and the differential assay technique was applied in an investigation of the effect of heat on the vitamin B6 activity of milk.4. It was found that pyridoxal accounted for about 80% of the vitamin B6 activity of raw milk, the other 20% being due to pyridoxamine.5. In the manufacture of evaporated milk there was a marked fall in the pyridoxal and a slight increase in the pyridoxamine content. The overall loss was some 60%.6. On storage of evaporated and of sterilized liquid milk at room temperature there was a further loss of vitamin B6 activity. Most of the residual activity in stored evaporated milk appeared to be due to a substance other than pyridoxal or pyridoxamine, possibly pyridoxine.
The effect of heat on the vitamin B6 of milk: II. A comparison of biological and microbiological tests of evaporated milk
Authors: Davies Mary K. , Gregory Margaret E. , Henry Kathleen M. 
Published: June 2009

1. For chicks and rats pyridoxine, pyridoxal and pyridoxamine were equally active in terms of the free bases when given separately from the diet.2. Under our experimental conditions pyridoxine mixed with the chick diet was stable, but 20% of pyridoxamine, and a variable amount of pyridoxal was lost.3. The vitamin B6 activities measured with Saccharomyces carlsbergensis, chicks and rats respectively and expressed as μg. pyridoxine/g. freeze-dried milk were: raw milk 3·4, 3·2 and 4·9; evaporated milk 1·0, 2·1 and 2·7; stored evaporated milk 0·6, 1·4 and 2·0. For the chicks the milks were mixed with the diets; they were given separately to the rats.4. The microbiological and biological results for raw milk agreed within the limits of experimental error. For the processed milks the differences between biological and microbiological tests were statistically significant.5. All three methods of assay showed a 45–70% loss of vitamin B6 activity on processing and a further loss of 30% of the remainder after storage for 6 months at room temperature.We are indebted to Mr J. Rothwell, Department of Dairying, University of Reading, for preparing the evaporated milk and to Dr B. Record, Ministry of Supply, Microbiological Research Establishment, Porton, for freeze-drying the milk. We should like to thank Dr S. K. Kon for his interest in this work.
Some volatile compounds in New Zealand Cheddar cheese and their possible significance in flavour formation: II. Volatile compounds of sulphur
Authors: Walker J. R. L. 
Published: June 2009

The volatile sulphur compounds present in New Zealand Cheddar cheese have been studied by means of gas entrainment and steam-distillation techniques. Hydrogen sulphide was the only sulphur compound which could be detected, and after removal of this compound from the gas stream or steam distillate only a mixture of carbonyl compounds remained. Subsequent removal of these compounds completely destroyed the original cheesy aroma of the gas stream or distillate.The parts played by hydrogen sulphide and carbonyl compounds in Cheddar cheese flavour are discussed.The author wishes to record his gratitude to Dr H. R. Whitehead and Dr W. A. McGillivray for their helpful advice and criticism and to Mr P. L. McLaughlin for technical assistance.
The use of an oxidation-reduction indicator to compare the oxygen permeabilities of films for rindless cheese
Authors: Dolby R. M. 
Published: June 2009

Slices and blocks of cheese were coloured with aqueous methylene blue solution and vacuum-packed or wrapped in the films to be compared. The extent of bleaching of the dye after 14 days gave a good indication of the extent to which oxygen was excluded by the film. Similar results were obtained with vacuum-packed slices and with wrapped rindless cheeses.With polythene-coated and wax-coated MSAT cellophane films there was little or no reduction of methylene blue on the cheese surface. Similar films, including a lamination of foil or MXXT cellophane, allowed complete or almost complete bleaching.
Identification of lactobacilli from Cheddar cheese by chromatography
Authors: Cheeseman G. C. 
Published: June 2009

SummaryThe technique of paper chromatography of bacterial extracts has been successfully applied to the routine examination of lactobacilli from cheese. One hundred and nine strains isolated on selective media have been grouped by their chromatogram patterns, and selected strains from these groups have been shown to have biochemical characteristics giving relationships which are in agreement with the chromatogram groupings. The results indicate that the technique can be used routinely for the rapid identification of strains of lactobacilli.
Production of acetone and acetaldehyde by lactic streptococci
Authors: Harvey R. J. 
Published: June 2009

SummarySeven strains of Streptococcus cremoris, four strains of Str. lactis, and one strain of Str. diacetilactis were examined for their ability to produce aldehydes and methyl ketones when grown in skim-milk. All strains were found to produce acetaldehyde and seven also produced acetone. No other aldehydes or methyl ketones were detected in any of the cultures.A method for the quantitative estimation of mixtures of aldehydes and methyl ketones by means of paper chromatography of their 2,4-dinitrophenylhydrazones is described.
Lactobacilli in raw milk and in Cheddar cheese
Authors: Perry K. D. , Sharpe M. Elisabeth 
Published: June 2009

SummaryThe lactobacillus flora of the mixed morning and evening milk of a single herd and of sixty Cheddar cheese made from this milk, unheated, was examined over a period of 12 months. Few lactobacilli (usually not more than 1/ml) were found in the milk samples, and were identified asLactobacillus plantarum, L. casei, L. brevis, L. fermentiand unclassified strains. In addition,Pediococcus cerevisiaeand leuconostoc species were isolated on the selective medium used, the leuconostocs occurring more frequently than either the lactobacilli or the pediococci. The lactic-acid bacteria in the cheese varied considerably, both quantitatively and qualitatively. Although in general the same species of organisms were isolated from the cheese as from the milks, the relative frequencies of occurrence were not the same, leuconostocs being found much more often in milk than in cheese, andL. plantarumandL. caseimore frequently in cheese. No association between numbers or types of lactic-acid bacteria and flavour of the cheese was noted, nor did the season of the year or the ration fed to the milking herd affect the lactobacillus flora of the milk.
Genetical aspects of maximum rate of flow during milking
Authors: Donald H. P. 
Published: June 2009

SummaryRates of flow of milk during milking have been observed on twin and single-born dairy cows with the aid of a device for continuous recording of weight of milk extracted. Each cow has been characterized by a maximum rate arrived at by averaging morning and evening observations on 2 days. Only this maximum rate has been studied.Repeatability was high (0·8–0·9) whether measured from day to day or from lactation to lactation. Maximum rate of flow was 10–16% higher in second than in first lactations. The range extended from under 2 lb/min to over 7 lb/min.Lactation yield of milk varied significantly with rate, rising about 50 gal for an increase of 1 lb/min. This relation is reduced or eliminated by taking into account by partial regression analysis either maximum weekly yield or the increase from the second to the peak week of lactation.Although the higher yielding cows had larger udder areas bounded by the four teats, the regression of 305-day milk yield on rate was not changed much by taking udder area into account. Cows with short teats milked faster and had higher yields than cows with longer teats.Differences in yield among the four quarters widened slightly between 1 and 3 months of lactation regardless of rate of flow, except possibly in the three slowest milking cows. In these the differences increased three times as much as in the other cows. The wider the inter-quarter differences in yield the less the proportion of milk obtained at the maximum rate.Heritability of maximum rate of flow derived from observations on paired singleborn cattle and twins was 85%. Field data would probably yield a value of 60–70%. Appropriate selection of breeding stock would effectively alter rate of flow, but there is no reason yet to expect yield of milk to change except perhaps by reducing the incidence of very slow milking cows.
Fishy flavour in dairy products: III. The volatile compounds associated with fishy flavour in washed cream
Authors: Forss D. A. , Dunstone E. A. , Stark W. 
Published: June 2009

SummaryWhen washed cream was treated with copper and ascorbic acid and held at 2°C for 1–5 days a strong metallic, fish-oil flavour developed. Compounds responsible for the flavour were isolated and identified. Gas chromatographic separation of a flavour concentrate on a silicone oil column gave six characteristic flavour fractions which, in order of elution, were described as painty or drying oil, oily, mushroom, metallic, tallowy and cucumber. The flavours of all fractions were predominantly caused by carbonyl compounds and the oily and metallic fractions were the main contributors to the typical fish-oil flavour. The following compounds were characterized: n-pentanal and pent-2-enal in the painty fraction; n-hexanal, n-heptanal and hex-2-enal in the oily fraction; hept-2-enal and a carbonyl compound with a mushroom odour in the mushroom fraction; a carbonyl compound with a metallic odour in the metallic fraction; n-octanal, n-nonanal, oct-2-enal and hepta-2,4-dienal in the tallowy fraction; and non-2-enal in the cucumber fraction.
The effect on milk yield of three times a day milking and of increasing the level of residual milk
Authors: Elliott Gillian M. 
Published: June 2009

SummaryExperiments were made to determine the effects on yield and butterfat percentage of three times a day milking and of inefficient milking using cows whose milk secretion rates had been shown to be unaffected by the milk accumulation involved. The milking treatments were applied to half-udders of the same cow to ensure that there was no difference between each pair of experimental units in the amount of oxytocic hormone released by the pituitary gland.Milking three times a day compared with twice a day over a 39-day period resulted in an increase of 12% in both milk and butterfat yields. Increasing the residual milk by 1 lb in each half-udder for a 39-day period caused a 15% decrease in both milk and butterfat yields. It was concluded that since the cause of these findings could be neither the direct effect of differences in milk accumulation nor the effect of different amounts of oxytocic hormone, some local cell effect was involved, activated either by differences in the amount of residual milk or by long-term effects of differences in milk accumulation.
The occurrence and significance of blood in bovine milk
Authors: Rammell C. G. 
Published: June 2009

SummaryResults are given of the examination for blood of 3214 milk samples from 935 cheese factory supplies. Over 75% of the milks contained less than 2·5 ppm. blood. Excessive blood was due to factors largely controllable by an efficient farmer, and so may be used as an indicator of poor dairy herd management and shed hygiene. No evidence could be obtained that the concentrations of blood likely to be found in commercial milk have any adverse effect on the keeping quality of whole milk or butter.
The estimation of dissolved oxygen in anhydrous milk fat
Authors: McDowell A. K. R. 
Published: June 2009

SummaryDissolved oxygen in anhydrous milk fat is reacted with an aqueous manganous-ferrous hydroxide suspension at 50 °C. The mixture is acidified and after separation into two layers the amount of ferric iron in the aqueous layer is estimated by iodometric titration. The procedure is relatively simple and is suitable for routine testing of milk fat.
The effect of feeding dried sugar-beet pulp on the intake and production of dairy cows
Authors: Castle M. E. , Drysdale A. D. , Watson J. N. 
Published: June 2009

SummaryThree rations were compared in a 15-week winter feeding experiment using 12 Ayrshire cows. All the cows received silage 3 times a day and concentrates; ration A contained no sugar-beet pulp whilst ration B contained 6 lb of pulp and ration C 12 lb.The total weights of dry matter consumed were 29·7, 32·3 and 33·4 lb/day, respectively, on treatments A, B and C. For every 1 lb of extra sugar-beet pulp dry matter eaten the decline in the dry weight of the other feeds consumed was 0·50 lb on treatment B and 0·55 lb on treatment C. The main decrease was in the silage part of the ration. The weights of starch equivalent (S.E.) consumed daily were 18·0, 19·8 and 20·7 lb on rations A, B and C, respectively, with mean daily milk yields of 38·2, 39·3 and 39·7 lb, giving a response of 0·55 lb milk/lb extra S.E. between rations A and C. The corresponding fat percentages of the milks did not differ significantly from each other but the solids-not-fat (SNF) percentages increased significantly from 8·76% on ration A to 8·88% on ration C. The average response per lb extra S.E. was 0·044% SNF and the increase was in the protein fraction of the milk. The cows were significantly heavier on rations B and C than on ration A. The inclusion of beet pulp in rations B and C had no adverse effect on the taste of the milk.
Studies on the effect of heat treatment during processing on the viscosity and stability of high-fat market cream
Authors: Rothwell J. 
Published: June 2009

SummaryThe viscosity of cream increased with increasing fat content, and higher values were obtained if the cream was separated at 38–43 °C rather than above 55 °C, and if the cream was cooled to below 15 °C before storage at 20 °C. The ‘type’ of viscosity varied with cooling and storage conditions; for example, cream cooled below 20 °C and stored at 20 °C gave increased viscosity readings with increased rates of shear due to churning of the cream, while the behaviour of cream cooled only to 20 °C was Newtonian.Cream stability as measured by free fat content decreased with increasing fat content above about 42%, with low temperature separation (38–45 °C), with cooling to below 15 °C before storage at 20 °C, and with increased pressure at temperatures below 15 °C.Dilatometric study of the amount of fat crystallization indicated that larger amounts of crystallization resulted in higher final viscosity and free fat content.
Estimation by gas chromatography of 5β-pregnane-3α, 20α-diol in the urine of normal lactating and ketosed cows
Authors: Heitzman R. J. 
Published: June 2009

SummaryThe measurement by gas chromatography of pregnanediol in the urine of normal and ketosed cows in the first 3 months of lactation is described. Mean pregnanediol levels, corrected for recovery losses, are reported for 3 groups of cows, namely: normal lactating cows 30·7 μg/1 urine; experimentally induced ketosed cows 22·3 μg/1 urine; and primary spontaneously ketosed cows, 31·4 μg/1 urine. No significant differences between the 3 groups of animals were found.
The production of L(+) and D(−) lactic acid in cultures of some lactic acid bacteria, with a special study ofLactobacillus acidophilusNCDO 2
Authors: Garvie Ellen I. 
Published: June 2009

SummaryA study of the production of L(+) and D(−) lactic acid in cultures of DL forming lactic acid bacteria has shown that they can be divided into 2 groups. The first includes the thermobacteria andPediococcus cerevisiaein which the percentage of L(+) lactic acid is high initially but decreases as the cultures grow. The second includesLactobacillus plantarumand the heterofermentative lactobacilli and in cultures of these species the percentage of L(+) acid changes little during growth and is generally below 50% of the total.In a strain ofLactobacillus acidophilusit has been found that if the pH is kept constant during growth the proportion of L(+) lactic acid decreased. However, when acid production stopped the proportion of total acid which is the L(+) isomer is greater than the proportion at the same stage of development in cultures where the pH was not adjusted. Cells harvested from young cultures formed more L(+) acid than cells harvested from older cultures.There is some evidence that the composition of the medium can affect the ratio of L(+):D(−) lactic acid.