386. Variations in morphology of Streptococcus lactis when grown in raw and heated milk

1949 ◽  
Vol 16 (2) ◽  
pp. 161-166 ◽  
Author(s):  
C. S. Morris ◽  
M. A. Edwards
Keyword(s):  
Methylene Blue ◽  
Incubation Period ◽  
Incubation Time ◽  
Raw Milk ◽  
Morphological Characters ◽  
Streptococcus Lactis ◽  
Heated Milk ◽  
Methylene Blue Reduction ◽  
The Difference ◽  
By Products

1. Streptococcus lactis cultures were found to vary considerably in their morphological characters when grown in raw and heated milk.2. This variation in morphology was found to be the main cause for the difference in colony counts between inoculated raw milk and milk heated to 70° C. for 1 hr. over a 6 hr. incubation period at 37° C.3. Similar T.M.C.'S on inoculated raw and heated milk during incubation at 37° C. explained why the methylene-blue reduction times were the same.4. It is thought that denaturation of protein may be responsible for the production of short chains in heated milk.5. The by-products of growth of Str. lactis are responsible for the production of short chains in raw milk after a long incubation time at 37° C.

INFLUENCE OF REFRIGERATED STORAGE ON DYE REDUCTION TIME OF MILKS

1952 ◽  
Vol 15 (1) ◽  
pp. 8-12 ◽  
Author(s):  
C. K. Johns
Keyword(s):  
Methylene Blue ◽  
Close Agreement ◽  
Raw Milk ◽  
Refrigerated Storage ◽  
Methylene Blue Reduction ◽  
Dye Reduction ◽  
Standard Plate ◽  
Plate Counts ◽  
The Difference ◽  
Better Than

Working with 100 weigh-can samples from 5 dairies it was found that icing for even 2 hours slightly retarded reduction of methylene blue; after 23 hours the effect was somewhat greater when the dye was present, but not when it was added just before incubation. With resazurin, on the other hand, there was better agreement when the dye was present during overnight storage. In no instance was the difference statistically significant. Methylene blue reduction times were in surprisingly close agreement with standard plate counts on the raw milk, while the correlation between reduction times (raw) and plate counts after laboratory pasteurization was better than was expected.

249. Studies on the methylene-blue reduction test II. Comparison between the old and the modified methods

1940 ◽  
Vol 11 (1) ◽  
pp. 43-50 ◽  
Author(s):  
T. Matuszewski ◽  
J. Supińska
Keyword(s):  
Methylene Blue ◽  
Raw Milk ◽  
The Other ◽  
Initial Number ◽  
Reduction Time ◽  
Reduction Test ◽  
Modified Method ◽  
Methylene Blue Reduction ◽  
Number Of Cells ◽  
Stimulation Of

In order to compare the old and the modified methods of the methyleneblue reduction test, 185 samples of raw milk were examined. We followed Wilson's method absolutely, but included two tubes in each test, one of which was inverted and the other not.The results obtained and their interpretation agreed with the theoretical expectations given in our previous paper, and briefly outlined at the beginning of the present paper.It is found that the deviations in the reduction time, corresponding to a given initial number of cells, are smaller by the modified than by the old method, and that the average time of reduction is shorter.The smaller variation in the reduction time corresponding to a given number of cells at the beginning of the test is due probably to a more uniform distribution of the bacteria in the milk following the inversion of the tube. Wilson's suggestion that the shortening of the reduction time in the modified method is due to the stimulation of bacterial growth proves to be entirely correct. We obtained the average coefficients of multiplication in the old method of 0·660, and in the modified of 0·885.Our results confirm on the whole the positive value of the modification of the methylene-blue reduction test as suggested and worked out by Wilson.

317. The resazurin and methylene-blue tests as a measure of the keeping quality of milk

1945 ◽  
Vol 14 (1-2) ◽  
pp. 21-27 ◽  
Author(s):  
E. B. Anderson ◽  
G. S. Wilson
Keyword(s):  
Methylene Blue ◽  
Correlation Coefficients ◽  
Raw Milk ◽  
Accurate Estimate ◽  
Human Consumption ◽  
Methylene Blue Reduction ◽  
Keeping Quality ◽  
Methylene Blue Test ◽  
Quality Of Milk

1. During four periods equally spaced throughout the year raw milks coming from surrounding farms into the Buckingham receiving station were examined by (a) the 10 min. resazurin test, (b) the 1 hr. resazurin test, (c) the resazurin test in which the time to reach disk 1 was recorded, (d) the modified methylene-blue test, and (e) a keeping quality test based on taste and alcohol precipitation. Altogether, 2588 samples were examined.2. Table 2, in which the correlation coefficients are worked out between the results of the dye and the K.Q. tests, shows that there is little to choose between the methylene-blue test and the time to reach disk 1 in the resazurin test; but since an average of only 15 min. was saved by carrying out the resazurin test, there seems little advantage to be gained by the use of this test. Both of these tests are superior to the 10 min. and the 1 hr. resazurin tests.3. A comparison of Tables 5–7, in which the average K.Q. of the milks corresponding to different disk numbers or reduction times is recorded, shows that the methylene-blue test affords the best indication of the K.Q.4. A study of Table 3, setting out the relation between the 10 min. resazurin and the methylene-blue reduction tests, shows that 99% of milks giving a 0–½ reading in the resazurin test reduce methylene blue within 30 min. and 80 % of them within 10 min.; but that, of milks reducing methylene blue within 30 min., only 53% give a disk reading of 0–½ in the 10 min. resazurin test. If it is agreed that no raw milk on arrival at the creamery which reduces methylene blue within 30 min. and which has, according to Table 7, an average K.Q. of only about 5 hr. at the time of testing, is fit for human consumption, then it is clear that the present rejection standard in the 10 min. resazurin test passes nearly 50% of unsatisfactory milks.5. The data recorded in this paper all go to show that the best indirect index of the K.Q. of raw milk is afforded by the methylene-blue test as carried out by the method officially laid down by the Ministry of Health.6. On the other hand, if time is an overruling consideration, then a slightly less accurate estimate of the K.Q. of raw milk is afforded by the 1 hr. resazurin test. It must be pointed out, however, that the figures given in Table 6 suggest that below disk 2 there is some irregularity in the relation between the disk numbers and the K.Q. If the 1 hr. resazurin test should come into use for the routine grading of milk, a revision of the present tints at the lower end of the scale might prove desirable.

SOME FACTORS AFFECTING THE CORRELATION OF METHYLENE BLUE REDUCTION TIMES AND STANDARD PLATE COUNTS OF RAW MILK

1966 ◽  
Vol 29 (8) ◽  
pp. 255-259
Author(s):  
A. Richard Brazis ◽  
L. A. Black
Keyword(s):  
Methylene Blue ◽  
Standard Procedure ◽  
Raw Milk ◽  
Bacterial Counts ◽  
Factors Affecting ◽  
Methylene Blue Reduction ◽  
Standard Plate ◽  
Plate Counts

Summary Standard plate and psychrophilic bacterial counts, on 312 samples of milk collected from farm bulk tanks and milk cans, were compared with methylene blue reduction times using the standard procedure or preliminary incubation of samples at 55 F for 18 hr prior to testing. When psychrophilic bacterial counts were less than 100,000/ml, according to standard plate counts a high proportion of methylene blue reduction times were properly classified. However, psychrophilic bacterial counts greater than 100,000/ml did not significantly decrease reduction times, thus a high proportion of such milks was not properly classified by methylene blue reduction times. The proportion of misclassification of samples having standard plate counts in excess of 200,000/ml and methylene blue reduction times of 5 and 6 hr was determined.

THE INFLUENCE OF DDT WETTABLE POWDER ON THE METHYLENE BLUE REDUCTION TEST IN MILK

1953 ◽  
Vol 16 (1) ◽  
pp. 4-8 ◽  
Author(s):  
S. J. Millian ◽  
H. H. Weiser
Keyword(s):  
Methylene Blue ◽  
Raw Milk ◽  
Forage Crops ◽  
Reduction Test ◽  
Methylene Blue Reduction ◽  
Wettable Powder

DDT has been detected in the milk of cows fed forage crops exposed to the insecticide. DDT, in the form of a wettable powder, was added to raw milk to determine its effect on the methylene blue reduction test. The results indicate that the presence of appreciable quantities of DDT wettable powder materially interfere with the accuracy of the test. Care should be exercised in interpreting reduction tests of milk containing this insecticide.

Inheritance of Some Morphological Characteristics of Parental Lines in Mustard-Rape Hybrid

2020 ◽  
pp. 23-30
Keyword(s):  
First Generation ◽  
Agronomic Traits ◽  
Morphological Characteristics ◽  
Morphological Characters ◽  
Hybrid Plant ◽  
Distant Hybridization ◽  
Degree Of Dominance ◽  
Whole Plant ◽  
Row Width ◽  
The Difference

Distant hybridization is known to play an important role in expanding the gene pool of any crop. It is believed that the combination of different genomes in one nucleus, as a rule, is accompanied by the phenomenon of “genomic shock”, resulting in a variety of genetic and epigenetic changes. This provides a wealth of material for the selection of genotypes adapted to different environmental conditions. Interspecific hybrids in different combinations were obtained in the genus Brassica, however, until now, interest in distant hybridization in this genus has not died out, since such important crops as rapeseed and mustard demand an improvement of many important agronomic traits. The aim of this work was to study the degree of manifestation of morphological characters of a leaf, flower, and plant as a whole in the hybrid obtained by crossing of brown mustard of the variety Slavyanka and a collection specimen of spring rape. Seeds were sown in the spring of 2019 in a field with 30 cm row width. During the flowering period a number of morphological characters of a flower, leaf, and the whole plant were analyzed. Each parameter was evaluated with 10 plants. The degree of dominance in first-generation hybrid was calculated by the formula of Beil, Atkins (1965). The dominance coefficients were not determined in the case when the difference between the parental samples was insignificant. Differences between parental samples were determined by Student t-test. The level of heterosis was calculated according to the formula of Rasul et al (2002). In a mustard-rapeseed hybrid, the size of the leaves of the lower row was inherited by the type of rapeseed, which had larger leaves than mustard. The height of the hybrid plant was inherited by the type of mustard (hp = 1.32, Ht = 4.89%), and intermediate inheritance was observed for the length of the internodes (hp = -0.48). The size of the flower petals and sepals was inherited by the type of rapeseed, and significant heterosis was observed for the length of the pistil (Ht = 33.57%). The data obtained are of interest for understanding the interaction of genes of different genomes in the genus Brassica.

scholarly journals The Water Footprint of Primary and Secondary Processing of Beef from Different Cattle Breeds: A Value Fraction Allocation Model

2021 ◽  
Vol 13 (12) ◽  
pp. 6914
Author(s):  
Frikkie Alberts Maré ◽  
Henry Jordaan
Keyword(s):  
Water Footprint ◽  
Negative Relationship ◽  
High Water ◽  
Allocation Model ◽  
Cattle Breeds ◽  
A Value ◽  
Average Production ◽  
High Water Intake ◽  
The Difference ◽  
By Products

The high water intake and wastewater discharge of slaughterhouses have been a concern for many years. One neglected factor in previous research is allocating the water footprint (WF) to beef production’s different products and by-products. The objective of this article was to estimate the WF of different cattle breeds at a slaughterhouse and cutting plant and allocate it according to the different cuts (products) and by-products of beef based on the value fraction of each. The results indicated a negative relationship between the carcass weight and the processing WF when the different breeds were compared. Regarding a specific cut of beef, a kilogram of rib eye from the heaviest breed had a processing WF of 614.57 L/kg, compared to the 919.91 L/kg for the rib eye of the lightest breed. A comparison of the different cuts indicated that high-value cuts had higher WFs than low-value cuts. The difference between a kilogram of rib eye and flank was 426.26 L/kg for the heaviest breed and 637.86 L/kg for the lightest breed. An option to reduce the processing WF of beef is to lessen the WF by slaughtering heavier animals. This will require no extra investment from the slaughterhouse. At the same time, the returns should increase as the average production inputs per kilogram of output (carcass) should reduce, as the slaughterhouse will process more kilograms.

scholarly journals Acoustic Characterization of Some Steel Industry Waste Materials

2021 ◽  
Vol 11 (13) ◽  
pp. 5924
Author(s):  
Elisa Levi ◽  
Simona Sgarbi ◽  
Edoardo Alessio Piana
Keyword(s):  
Thermal Characteristic ◽  
Environmental Benefits ◽  
Acoustic Properties ◽  
Physical Parameters ◽  
Industry Waste ◽  
Acoustic Characterization ◽  
Minimization Procedure ◽  
The Difference ◽  
By Products

From a circular economy perspective, the acoustic characterization of steelwork by-products is a topic worth investigating, especially because little or no literature can be found on this subject. The possibility to reuse and add value to a large amount of this kind of waste material can lead to significant economic and environmental benefits. Once properly analyzed and optimized, these by-products can become a valuable alternative to conventional materials for noise control applications. The main acoustic properties of these materials can be investigated by means of a four-microphone impedance tube. Through an inverse technique, it is then possible to derive some non-acoustic properties of interest, useful to physically characterize the structure of the materials. The inverse method adopted in this paper is founded on the Johnson–Champoux–Allard model and uses a standard minimization procedure based on the difference between the sound absorption coefficients obtained experimentally and predicted by the Johnson–Champoux–Allard model. The results obtained are consistent with other literature data for similar materials. The knowledge of the physical parameters retrieved applying this technique (porosity, airflow resistivity, tortuosity, viscous and thermal characteristic length) is fundamental for the acoustic optimization of the porous materials in the case of future applications.

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