scholarly journals The effect of storage on the coliform and Bacterium coli counts of water samples

1953 ◽  
Vol 51 (4) ◽  
pp. 559-571 ◽  
Author(s):  
Keyword(s):  
Water Samples ◽  
Room Temperature ◽  
Refrigerator Temperature ◽  
Significant Change

This investigation has been concerned with the changes that occur in the coliform and faecal coli content of water samples on storage at room and refrigerator temperatures for 6 hr. as compared with those occurring after 24 hr. storage.The examination was conducted by a 70-tube method using twofold diminishing volumes.The percentages of samples showing a significant change corresponding to at least a doubling or halving of the coliform content on storage were: (a) at room temperature after 6 hr. 24.7%, and after 24 hr. 38.3%; (b) at refrigerator temperature after 6 hr. 25.0%, and after 24 hr. 33.9%. The percentages of samples showing a significant change in the faecal coli content on storage were: (a) at room temperature after 6 hr. 18.7%, and after 24 hr. 34.6%; (b) at refrigerator temperature after 6 hr. 10.4%, and after 24 hr. 25.0%. The changes were preponderantly decreases and most of the large changes occurred after 24 hr.The investigation has shown that fewer changes occur after 6 hr. storage than after 24 hr. storage, and that storage for 6 hr. at refrigerator temperature is preferable to storage for 6 hr. at room temperature. Even so, some samples show significant changes after 6 hr. storage at refrigerator temperature; the coliform content is significantly altered in 25% of samples and the faecal coli content in 10% of samples.Samples of water should, therefore, be examined as soon as possible after collection, certainly within 6 hr., and during the period of transport to the laboratory they should be kept cold, if possible by ice.

scholarly journals The effect of storage on the coliform andBacterium colicounts of water samples. Overnight storage at room and refrigerator temperature

1952 ◽  
Vol 50 (1) ◽  
pp. 107-125 ◽  
Author(s):  
Keyword(s):  
Water Samples ◽  
Room Temperature ◽  
Considerable Proportion ◽  
Original Number ◽  
Refrigerator Temperature ◽  
Significant Change ◽  
Time Of Year

This investigation has been concerned with the changes that occur in the coliform and faecalcolicontent of water samples on storage at room and refrigerator temperature for 20–24 hr.On examination by a seventy-tube method, using twofold diminishing volumes, twenty-three out of 151 samples of water stored overnight at room temperature showed a significant increase in the presumptive number of conform organisms and twenty-nine a significant decrease. Of the same number stored in the refrigerator, ten showed a significant increase and twenty-six a significant decrease.Of 111 samples examined for faecalcoli, eight showed a significant increase on storage at room temperature and twenty-nine a significant decrease. Of the same number stored in the refrigerator, seven showed a significant increase and fifteen a significant decrease. The effects of the source of the water, the time of year and the original number of coliform organisms in the sample were examined.The present investigation has shown that in a considerable proportion of samples a significant change in the conform and faecalcolicontent does occur on overnight storage at room or refrigerator temperature. It may, perhaps, be safe to store samples under some conditions for shorter periods, but this is a matter for future investigation.

scholarly journals Producing Drink like Grafted Milk from Chickpeas and Evaluation of its Qualitative Properties

2020 ◽  
Vol 10 (03) ◽  
pp. 374-377
Author(s):  
Ibtihal Ismail Muhammad Al-Ani
Keyword(s):  
Room Temperature ◽  
Extraction Efficiency ◽  
Ph Value ◽  
Bacterial Number ◽  
Qualitative Properties ◽  
Product Density ◽  
Ph Values ◽  
Extraction Volume ◽  
Refrigerator Temperature ◽  
Soda Solution

The present study aimed to study the possibility of producing a drink that looks like grafted milk by using chickpeas and evaluate its physical, chemical, microbial, and sensory properties. The result showed the superiority of F treatment (soaking 100 grams of chickpeas at the refrigerator temperature 4ºC for 12 hours) over the rest seven treatments in extraction efficiency, which was 70%, while, it was 50.5% in H treatment (soaking 100 grams of chickpeas in the heated water at 60ºC for 30 minutes). The highest value of the product density was after water and flavorings addition in the D treatment (soaking 100 grams chickpeas in 0.05 soda solution at 60ºC for 30 minutes), and it was 0.97 g cm-3, compared with the lowest density 0.57 g cm-3 in A treatment (soaking 100 grams chickpeas in 0.05 soda solution at room temperature 25ºC for 12 hours). pH values were highest in A treatment compared with the other treatments, and its value was 7.66 in the 1st and 2nd day, after dissolving in a refrigerator at 4ºC, and then, for 5 minutes at room temperature 30ºC. The lowest value in the D treatment was 6.45 on the 1st day, and 6.87 on the 2nd day in the G treatment. On the 3rd day, the highest pH value was 7.13 in the D treatment, and the lowest value 6.79 was in the E treatment. pH highest value was 6.2 on the 4th day in A treatment. From the last results, it may be concluded that F treatment was the best in extraction efficiency, the final product density, and less total bacterial number, after dissolving for 5 days at refrigerator temperature 4ºC, and then, at room temperature 30ºC for 3 and 48 hours incubation. The best extraction volume and pH were in A treatment.

scholarly journals TOTAL Escherichia coli PADA SOSIS IKAN YANG DI-COATING DENGAN MIOFIBRIL ASAP CAIR SELAMA PENYIMPANAN

2016 ◽  
Vol 4 (1) ◽  
Author(s):  
Jupni Keno ◽  
Henny Adeleida Dien ◽  
Agnes Triasih Agustin
Keyword(s):  
Escherichia Coli ◽  
Nutritional Value ◽  
Room Temperature ◽  
Total Coliform ◽  
Fish Protein ◽  
Gram Negative ◽  
E Coli ◽  
Liquid Smoke ◽  
Refrigerator Temperature ◽  
Descriptive Method

Fish sausages are prepared foods that have a high nutritional value, but that is the weakness of this commodity is rapidly decaying nature. Bacterial pathogens that must be avoided include Escherichia coli. These bacteria are gram-negative, rod-shaped and motile spores are not. The purpose of this study is to calculate the total coliforms and E. coli in fish sausage coating of fish protein myofibrils Black Marlin (Makaira indica) during storage at room temperature (28–29°C), and refrigerator temperature (10–13°C). The method used is descriptive method, which is a study conducted to analyze an individual, the state, or the symptoms of a particular group. The results showed that the total coliform in fish sausage in coating with liquid smoke is stored at room temperature, the lowest value is 7 MPN/g, the highest of 120 MPN/g, while the lowest value refrigerator temperature is 7 MPN/g, the highest 93 MPN/g. Total coliform in fish sausage in smokeless liquid coating stored at room temperature with the lowest value is 7 MPN/g, the highest 210 MPN/g, while the lowest value refrigerator temperature is 7 MPN/g, and the highest is 120 MPN/g. Total coliform in fish sausages are not in the coating deposited at room temperature with the lowest value is 7 MPN/g, the highest of 240 MPN/g, at refrigerator temperature the lowest value is 7 MPN/g, and the highest is 150 MPN/g. Total E. coli showed that the fish sausage in coating with liquid smoke is stored at room temperature, the lowest value is 1 MPN/g, and the highest is 4 MPN/g, while the lowest value refrigerator temperature is <3 MPN/g, and The highest is 3 MPN/g. Total E. coli in fish sausage in smokeless coating liquid stored at room temperature, the lowest value is 2 MPN/g, and the highest is 4 MPN/g, while the temperature of the refrigerator lowest value is 1 MPN/g, and a high of 3 MPN/g. Total E. coli in sausages are not in the coating deposited at room temperature, the lowest value is 2 MPN/g, and the highest is 5 MPN/g, and the refrigerator temperature is the lowest rating 2 MPN/g, the highest is 4 MPN/g during storage .Keywords: fish sausage, coating, myofibril, Eschericia coli.  Sosis ikan merupakan makanan siap saji yang mempunyai nilai gizi tinggi, namun yang menjadi kelemahan dari komoniti ini adalah sifatnya yang cepat membusuk. Bakteri patogen yang harus dihindari antara lain Escherichia coli.  Bakteri ini bersifat gram negatif, berbentuk batang tidak spora dan bersifat motil. Tujuan penelitian ini yaitu untuk menghitung total koliform dan E. coli pada sosis ikan yang dicoating dari miofibril protein ikan Black Marlin (Makaira indica) selama penyimpanan suhu ruang (28–29°C), dan suhu kulkas (10–13°C). Metode penelitian yang digunakan adalah metode deskriptif, yaitu suatu penelitian yang dilakukan untuk menganalisa suatu individu, keadaan, gejala atau kelompok tertentu. Hasil penelitian menunjukkan bahwa total koliform pada sosis ikan yang dicoating dengan asap cair disimpan pada suhu ruang, nilai terendah yaitu 7 MPN/g, tertinggi 120 MPN/g, sedangkan pada suhu kulkas nilai yang terendah yaitu 7 MPN/g, tertinggi 93 MPN/g. Total koliform pada sosis ikan yang dicoating tanpa asap cair disimpan pada suhu ruang dengan nilai terendah yaitu 7 MPN/g, tertinggi 210 MPN/g, sedangkan pada suhu kulkas nilai yang terendah yaitu 7 MPN/g, dan tertinggi 120 MPN/g. Total koliform pada sosis ikan tidak dicoating disimpan pada suhu ruang dengan nilai terendah yaitu 7 MPN/g, tertinggi 240 MPN/g , pada suhu kulkas nilai terendah yaitu 7 MPN/g , dan tertinggi 150 MPN/g. Total E. coli menunjukkan bahwa pada sosis ikan yang dicoating dengan asap cair disimpan pada suhu ruang, yaitu nilai terendah 3 MPN/g, dan tertinggi 4 MPN/g, sedangkan pada suhu kulkas nilai terendah yaitu <3 MPN/g, dan tertinggi 3 MPN/g. Total E. coli pada sosis ikan yang dicoating tanpa asap cair disimpan pada suhu ruang, yaitu nilai terendah 3 MPN/g, dan tertinggi 4 MPN/g, sedangkan pada suhu kulkas nilai terendah yaitu <3 MPN/g , dan tertinggi 3 MPN/g. Total E. coli pada sosis tidak dicoatingdisimpan pada suhu ruang, yaitu nilai terendah 4 MPN/g, dan tertinggi 7 MPN/g, dan pada suhu kulkas yaitu nilai terendah 3 MPN/g, tertinggi 4 MPN/g selama penyimpanan.Kata kunci: sosis ikan, coating, myofibril, Eschericia coli.

PROPERTIES OF BOVINE Ac-GLOBULIN CONCENTRATES AND METHODS OF PREPARATION

1963 ◽  
Vol 41 (1) ◽  
pp. 2409-2421 ◽  
Author(s):  
Nobuo Aoki ◽  
Charles R. Harmison ◽  
Walter H. Seegers
Keyword(s):  
Human Plasma ◽  
Ammonium Sulphate ◽  
Protein Concentration ◽  
Room Temperature ◽  
Specific Activity ◽  
Barium Carbonate ◽  
Dry Weight ◽  
Physical Chemical ◽  
Bovine Plasma ◽  
Refrigerator Temperature

A procedure is described for retaining bovine plasma Ac-globulin activity as one part of the protein from plasma for every 1000 parts removed. The yields averaged 15%. The procedure involves removal of prothrombin with barium carbonate, isoelectric fractionation, fractionation with ammonium sulphate, chromatography on Amberlite IRC-50, and a second fractionation with ammonium sulphate. The procedure requires 2 days; however, the first day completes up to chromatography and the concentrate at that time is quite useful for many purposes. It is more stable than the product obtained after chromatography and the yields are higher. In absence of salts Ac-globulin is quite insoluble at pH 5.0. The final product usually contained some impurity. With the analytical ultra-centrifuge the S20in 0.1 M potassium chloride solution was found to be 4.2 at a protein concentration of 12.4 mg/ml. The specific activity was 1500 U./mg dry weight. Bovine plasma contains 120 U./ml or about 9 mg/100 ml. Assuming the same specific activity for human plasma the concentration is most likely near 1 mg/100 ml. The best stability conditions found were: 50% glycerol, pH 7.0, and 0.1 M calcium chloride. Under those conditions at room temperature all activity was retained 6 to 7 hours, at refrigerator temperature 24 hours, and at −60 °C for 1 month. In rabbits, antibodies were readily produced. Oxidizing agents destroyed the activity, while reducing agents did not, nor did they tend to stabilize. SH blocking agents destroyed the activity. The loss of activity in the presence of 0.0025 M parachloromercuribenzoate was recovered with 0.04 M cysteine. The molecule deteriorated while attempts were made to obtain physical chemical data; consequently, the molecular weight was calculated from an amino acid analysis and found to be 98,800. The reliability of this value is problematical. Human plasma was analyzed and found to contain 13 U./ml Ac-globulin. After 4 days storage, at room temperature, the prolonged prothrombin time of that plasma was completely restored with 13 units of Ac-globulin, which is equivalent to 8 μg.

Preservation of Cheese and Plain Yogurt by Low-dose Irradiation

1980 ◽  
Vol 43 (2) ◽  
pp. 114-118 ◽  
Author(s):  
S. YÜCEER ◽  
G. GÜNDÜZ
Keyword(s):  
Side Effects ◽  
Shelf Life ◽  
Total Dose ◽  
Room Temperature ◽  
Low Dose ◽  
Sorbic Acid ◽  
Low Doses ◽  
Dose Irradiation ◽  
Refrigerator Temperature ◽  
Number Of Bacteria

Irradiation preservation of Turkish kashar cheese and plain yogurt was studied using very low doses of Co-60 radiation. No side effects were observed below 0.15 Mrad. The number of bacteria killed was directly related to total dose up to 0.02 Mrad, then the effectiveness of the dose decreased. Coating cheese samples with a sorbic acid solution helped in reducing the number of bacteria by about 10–12% in irradiated samples. The shelf-life of irradiated samples stored at refrigerator temperature was almost the same as that of ones coated with sorbic acid but stored at room temperature. Mold formation in irradiated samples took three to four times longer than in nonirradiated ones. With plain yogurt the effect of total dose seemed to be the same as in cheese. Irradiation increased the shelf-life of yogurt three- to four-fold. Preservation by irradiation combined with refrigeration increased the shelf-life about five-fold.

Detection and Enumeration of Salmonella enteritidis in Fresh and Stored Eggs Laid by Experimentally Infected Hens

1992 ◽  
Vol 55 (3) ◽  
pp. 152-156 ◽  
Author(s):  
RICHARD K. GAST ◽  
C. W. BEARD
Keyword(s):  
Salmonella Enteritidis ◽  
Room Temperature ◽  
Laying Hens ◽  
Phage Type ◽  
The Other ◽  
Refrigerator Temperature

Laying hens were orally inoculated with a phage type 13a strain of Salmonella enteritidis (SE). Eggs laid by the infected hens were collected daily between the 4th and 14th d postinoculation and randomly allocated into three groups. One group of eggs was sampled on the day of collection, one group was held for 7 d at 7.2°C before sampling, and one group was held for 7 d at 25°C before sampling. The frequency and level of detectable contamination of egg contents by SE were determined for each group. Only 3% of the freshly laid eggs and 4% of the eggs held for 7 d at refrigerator temperature were identified as having SE-contaminated contents, whereas SE was isolated from the contents of 16% of eggs held for 7 d at room temperature. Enumeration of SE in contaminated eggs indicated greater numbers of SE in eggs held for 7 d at 25°C than in eggs from the other two groups, although most contaminated eggs in all three groups contained relatively small numbers of SE (generally less than 10/ml and rarely exceeding 100/ml).

Study of Forward Voltage Drift in Diffused SiC PiN Diodes Doped by Al or B

2005 ◽  
Vol 483-485 ◽  
pp. 989-992 ◽  
Author(s):  
S.I. Maximenko ◽  
Stanislav I. Soloviev ◽  
A.E. Grekov ◽  
A.V. Bolotnikov ◽  
Ying Gao ◽  
...  
Keyword(s):  
Current Density ◽  
Room Temperature ◽  
Stacking Faults ◽  
Applied Current ◽  
Forward Voltage ◽  
Pin Diodes ◽  
Applied Current Density ◽  
Voltage Drift ◽  
Significant Change ◽  
Degradation Testing

The degradation of diffused SiC PIN diodes during forward-biased operation was studied by first fabricating PIN diodes by diffusion of aluminum or boron into 4H-SiC substrates with n-type 10-15 µm thick epilayers doped by nitrogen up to 5x1015cm-3. The formed diodes were subjected to degradation testing under an applied current density of 200A/cm2 at room temperature. The majority of the Al diffused diodes demonstrated a voltage drift, ΔVf, of more than 2 V, while B-doped diodes showed no significant change in forward voltage. The EBIC mode of SEM was employed to monitor nucleation and expansion of stacking faults.

scholarly journals Chemical Variability in the Composition of Zhumeria majdae (Rech. F. & Wendelbo) Essential Oil According to Storage Time and Temperature

Horticulturae ◽  
2021 ◽  
Vol 7 (11) ◽  
pp. 463
Author(s):  
Akbar Karami ◽  
Fatemeh Tashani ◽  
Aminallah Tahmasebi ◽  
Filippo Maggi
Keyword(s):  
Essential Oil ◽  
Room Temperature ◽  
Storage Time ◽  
Storage Conditions ◽  
Gas Chromatography Mass Spectrometry ◽  
Average Value ◽  
Oil Storage ◽  
Chemical Variability ◽  
Refrigerator Temperature ◽  
Storage Temperatures

Zhumeria majdae (Rech. F. & Wendelbo) is an aromatic herb belonging to the Lamiaceae family, traditionally employed in the Persian medicine for the treatment of a wide number of diseases. In the present study, the chemical composition of Z. majdae essential oil obtained from the plant’s aerial features, and stored at various temperatures (refrigerator temperature 4 °C, freezer temperature −20 °C, and room temperature 20 ± 3 °C) and times (0, 3, 6, and 9 months) was studied. The essential oil was isolated through hydrodistillation, and its composition was evaluated by gas chromatography/mass spectrometry (GC/MS). The results showed that the composition of essential oils changed as a function of the various storage temperatures and times. Linalool (34.85–48.45%), camphor (27.09–39.17%), limonene (1.97–4.88%), and camphene (1.6–4.84%) made up the main volatile compounds which showed differences in their concentrations according to the various storage conditions. Notably, when compared to a non-stored treatment sample (analyzed immediately after essential oil collection), the amount of linalool and camphor increased in all samples stored in all conditions of temperature and time, with the exception of the samples stored for nine months at room temperature. On the other hand, limonene and camphene contents decreased during the storage treatments, showing that the highest content of these compounds occurred in the non-stored treatment. Essential oil storage at the freezer temperature and for three months storage time resulted in the highest average value of the major constituents, highlighting these as the best conditions for obtaining the highest content of the major compounds.

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