Survival of indigenous enteric viruses during storage of waste water sludge samples

1986 ◽  
Vol 32 (8) ◽  
pp. 645-648 ◽  
Author(s):  
Christon J. Hurst ◽  
Tamara Goyke
Keyword(s):  
Storage Temperature ◽  
Virus Titer ◽  
Enteric Viruses ◽  
Virus Inactivation ◽  
Least Squares Regression ◽  
Rates Of Change ◽  
The Stability ◽  
Solids Content ◽  
Virus Survival ◽  
Observation Period

The stability of indigenous enteric viruses in samples of settled primary and mixed-liquor activated sludges was studied at 2, 23, and −70 °C. Changes of virus titer which occurred in these samples were followed during an 84-day observation period, with rates of change then calculated by least-squares regression. Virus survival was found to be statistically dependent (p ≤ 0.05) upon storage temperature but not sludge solids content. Based upon the observed rates of inactivation, the average times which would be required for a 90% decrease in virus titer are 26 days at 23 °C, 180 days at 2 °C, and 163 days at −70 °C. As a group, the rates of virus inactivation observed at 2 °C were statistically different (p ≤ 0.05) from those observed at 23 °C, but not different from those observed at −70 °C. The three study temperatures were selected to approximate holding of samples in an air-conditioned room, on wet ice (H2O), and on dry ice (CO2).

Stability of viruses in waste water sludge eluates

1986 ◽  
Vol 32 (8) ◽  
pp. 649-653 ◽  
Author(s):  
Christon J. Hurst ◽  
Tamara Goyke
Keyword(s):  
Waste Water ◽  
Least Squares ◽  
Storage Temperature ◽  
Virus Titer ◽  
Virus Inactivation ◽  
Least Squares Regression ◽  
Rates Of Change ◽  
Virus Survival ◽  
Calculated Average ◽  
Observation Period

The survival of indigenous enteric viruses in samples of unconcentrated and concentrated waste water sludge eluates, which had been prepared using a combination beef extract elution – organic flocculation concentration procedure, was studied at 2, 23, and −70 °C. Changes of virus titer occurring in the samples were followed during an 84-day observation period, with rates of change then calculated by least-squares regression. Virus survival in both types of eluates was statistically dependent (p ≤ 0.05) upon storage temperature. Based upon the observed rates of inactivation the average times which would be required for a 90% decrease (one log10 unit) in virus titer for unconcentrated eluates are 27 days at 23 °C, 198 days at 2 °C, and 375 days at −70 °C. The calculated average times required for a 90% decrease in virus titer for concentrated eluates are 22 days at 23 °C, 132 days at 2 °C, and 246 days at −70 °C. In both types of eluates the rates of virus inactivation at 2 °C were statistically different from those observed at 23 °C, but not different from those observed at −70 °C. The three study temperatures were selected to approximate holding of samples in an air-conditioned room, fluid on wet ice (H2O), and frozen on dry ice (CO2).

Thermal and temporal stability on the enteric viruses infectivity in surface freshwater

2015 ◽  
Vol 16 (3) ◽  
pp. 620-627 ◽  
Author(s):  
V. Moresco ◽  
N. A. Damazo ◽  
C. R. M. Barardi
Keyword(s):  
Storage Temperature ◽  
Quantitative Polymerase Chain Reaction ◽  
Temporal Stability ◽  
Enteric Viruses ◽  
Human Adenovirus ◽  
Adenovirus Type ◽  
Storage Conditions ◽  
Murine Norovirus ◽  
Log Reduction ◽  
The Stability

The present study aimed to evaluate the stability of Human Adenovirus type 2 (HAdV2) and Murine Norovirus 1 (MNV-1) in surface freshwater samples stored at different temperatures. For HAdV2 the stability decreased with increasing temperatures (−80 > −20 > 4 > 22 °C). The time required to reach one log reduction in viral titers (T90) was similar among all the times and temperatures by different cell-culture based methods and reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The HAdV2 stability decreased with the time of storage temperature and methods employed, aside from samples stored at 22 and 4 °C which showed the lowest T90 values (50 days). For MNV-1, the samples stored at 22 and −20 °C showed higher log10 decay values, followed by 4 and −80 °C; while genome persistence was ranked as −80 > −20 > 4 > 22 °C. The T90 values were lower for samples stored at 22 °C (33 days), followed by 4, −20 and −80 °C with 111, 100 and 333 days, respectively. The results indicate that, under laboratory storage conditions, freshwater samples should be kept at 4 °C and at −80 °C for short- and long-term periods, respectively. This study provided useful information about thermal and temporal stability of the enteric viruses regarding sample storage conditions.

Hydrothermic Treatment Effects on Some Ripening Changes on Mango Fruits (Mangifera indica L) `Crillo de Bocado' during Storage: II. Chemical Parameters

HortScience ◽  
1998 ◽  
Vol 33 (3) ◽  
pp. 520e-520
Author(s):  
Juan E Manzano ◽  
Oswaldo Valor
Keyword(s):  
Low Temperature ◽  
Storage Time ◽  
Storage Temperature ◽  
Mangifera Indica ◽  
Soluble Solids ◽  
Soluble Solids Content ◽  
Chemical Parameters ◽  
Randomized Design ◽  
Solids Content ◽  
Green Stage

Mango fruits `Criollo de Bocado' harvested at the mature-green stage were treated with a hydrothermic treatment of 55 °C for 3 min and stored for 20 days at temperatures of 10 ± 2, 15 ± 2 and 28 ± 2 °C. A randomized design 2 × 3 × 4 with three replications was used. Some chemical parameters were analyzed, such as total soluble solids content (% TSS), pH, tritatable acidity, and TSS/tritatable acidity ratio. TSS content increased with storage time at low temperature. The pH increased measurably with storage temperature, while tritatable acidity values results had inconsistent data.

Photochemical stability of warfarin potassium in powdered pharmaceutical tablets

2021 ◽  
Vol 32 (2) ◽  
pp. 115-129
Author(s):  
Emi Horiguchi-Babamoto ◽  
Makoto Otsuka
Keyword(s):  
High Performance ◽  
Partial Least Squares Regression ◽  
Pediatric Patients ◽  
Reversed Phase ◽  
Least Squares Regression ◽  
Brand Name ◽  
Pharmaceutical Tablets ◽  
Light Stability ◽  
Warfarin Potassium ◽  
The Stability

BACKGROUND: Warfarin potassium (Wf) commercial tablets originally formulated for adults are ground before administration to pediatric patients and elderly patients with dysphagia. OBJECTIVE: The present study investigated the effect of tablet grinding on the photostability of four types of commercial Wf tablets and predicted the photostability of the tablet powders by chemometric analysis. METHODS: The photodegradation of Wf content was evaluated by reversed-phase column high-performance liquid chromatography with ultraviolet (HPLC-UV). RESULTS: The bulk Wf powder was relatively photostable, whereas ground Wf tablets underwent substantial photodegradation. The photostability of the ground powders of a brand-name Wf commercial tablet and three generic Wf commercial tablets was quantitatively assessed and compared. In certain cases, the Wf in all the three ground generic tablets was less photostable than in the ground brand-name tablets. After 28 days of light irradiation, the Wf content decreased to 69.79% in the brand-name tablets, while it was 31.90% in some generic tablets. To clarify the factors influencing the relative photostability in various Wf formulations, we analyzed the intermolecular interactions between the active ingredient and the excipients by partial least-squares regression analysis based on photostability screening for each additive. CONCLUSION: The results suggested that the additives light anhydrous silicic acid and povidone adversely affect the stability of Wf tablets. In addition, the light stability of ground tablets was affected considerably by their formulation.

scholarly journals The Effect of pH and Storage Temperature on the Stability of Emulsions Stabilized by Rapeseed Proteins

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1657
Author(s):  
Karolina Östbring ◽  
María Matos ◽  
Ali Marefati ◽  
Cecilia Ahlström ◽  
Gemma Gutiérrez
Keyword(s):  
Zeta Potential ◽  
Storage Temperature ◽  
Emulsion Stability ◽  
Press Cake ◽  
Strong Impact ◽  
Soy Lecithin ◽  
Rapeseed Protein ◽  
Rapeseed Proteins ◽  
Precipitation Ph ◽  
The Stability

Rapeseed press cake (RPC), the by-product of rapeseed oil production, contains proteins with emulsifying properties, which can be used in food applications. Proteins from industrially produced RPC were extracted at pH 10.5 and precipitated at pH 3 (RPP3) and 6.5 (RPP6.5). Emulsions were formulated at three different pHs (pH 3, 4.5, and 6) with soy lecithin as control, and were stored for six months at either 4 °C or 30 °C. Zeta potential and droplet size distribution were analyzed prior to incubation, and emulsion stability was assessed over time by a Turbiscan instrument. Soy lecithin had significantly larger zeta potential (−49 mV to 66 mV) than rapeseed protein (−19 mV to 20 mV). Rapeseed protein stabilized emulsions with smaller droplets at pH close to neutral, whereas soy lecithin was more efficient at lower pHs. Emulsions stabilized by rapeseed protein had higher stability during storage compared to emulsions prepared by soy lecithin. Precipitation pH during the protein extraction process had a strong impact on the emulsion stability. RPP3 stabilized emulsions with higher stability in pHs close to neutral, whereas the opposite was found for RPP6.5, which stabilized more stable emulsions in acidic conditions. Rapeseed proteins recovered from cold-pressed RPC could be a suitable natural emulsifier and precipitation pH can be used to monitor the stability in emulsions with different pHs.

PRODUCTION OF GRANULATED INSTANT KISSEL BASED ON WHEY AND VEGETABLE RAW MATERIALS

2020 ◽  
Author(s):  
А.Л. Майтаков ◽  
Л.Н. Берязева ◽  
Н.Т. Ветрова ◽  
К.Б. Плотников
Keyword(s):  
Storage Temperature ◽  
Raw Materials ◽  
Storage Period ◽  
Technical Documentation ◽  
Plant Raw Materials ◽  
Temperature Conditions ◽  
Aronia Melanocarpa ◽  
Organoleptic Characteristics ◽  
Local Plant ◽  
The Stability

Разработан новый быстрорастворимый продукт (кисель) с определенным фазовым составом и строением на основе молочной сыворотки и местного растительного сырья – черноплодной рябины (Aronia melanocarpa). Разработана модель технологии производства быстрорастворимого гранулированного продукта (кисель) на основе молочной сыворотки и черноплодной рябины. Исследована сохраняемость киселя в трех температурных режимах: 1-й (21 ± 1)°С; 2-й с низкой плюсовой температурой (5 ± 1)°С; 3-й с повышенной (39 ± 1)°С при влажности окружающей среды 80%. По окончании годичного исследования сохраняемости при температурных режимах (21 ± 1)°С и (5 ± 1)°С изменений в органолептических показателях продукта не наблюдали. Скорость растворения продукта при температурных условиях хранения (21 ± 1)°С и (5 ± 1)°С не изменялась на протяжении 9 мес. Установлено, что при хранении в условиях пониженных положительных температур 4–6°С и в режиме комнатной температуры (21 ± 1)°С исследуемый пищеконцентрат по окончании 6 мес. хранения не изменил свойств по показателям качества. Сроки испытания продукта превышали по длительности в 2 раза заданный срок хранения (коэффициент запаса). Результаты испытаний явились основанием для разработки технической документации на производство быстрорастворимых гранулированных плодово-ягодных киселей. A new fast – soluble product (kissel) with a certain phase composition and structure based on whey and local plant raw materials Aronia melanocarpa. A model of technology for the production of a rapidly soluble granular product (kissel) based on whey and Aronia melanocarpa has been developed. The stability of kissel in three temperature modes was studied: 1st (21 ± 1)°C; 2nd with a low plus temperature (5 ± 1)°C; the 3rd with the increased (39 ± 1)°C at 80% ambient humidity. At the end of a year-long study at temperature conditions (21 ± 1)°С and (5 ± 1)°С, no changes in the organoleptic characteristics of the product were observed. Dissolution rate of the product under storage temperature conditions (21 ± 1)°C and (5 ± 1)°C did not change for 9 months. It is established that when stored at low positive temperatures 4–6°C. With and at room temperature (21 ± 1)°C. At the end of 6 months of storage, the food concentrate under study did not change its properties in terms of quality. The product testing period was 2 times longer than the specified storage period. The test results were the basis for the development of technical documentation for the production of instant granulated fruit and berry kissel.

scholarly journals Effects of heat treatment and storage temperature on the use of açaí drink by nutraceutical and beverage industries

2012 ◽  
Vol 32 (1) ◽  
pp. 9-14 ◽  
Author(s):  
Tatiane Regina Albarici ◽  
José Dalton Cruz Pessoa
Keyword(s):  
Temperature Effect ◽  
Storage Temperature ◽  
Life Time ◽  
Reaction Rate Constant ◽  
Anthocyanin Content ◽  
Order Kinetic ◽  
First Order ◽  
The Stability ◽  
And Storage ◽  
Anthocyanin Degradation

This study assesses the storage temperature effect on the anthocyanins of pasteurized and unpasteurized açaí pulp. The data was obtained using a pasteurized and lyophilized pulp (PLP) to evaluate the temperature effect (0, 25, and 40 °C). Part of non-pasteurized frozen pulp (NPP) was pasteurized (NPP-P) at 90 °C for 30 seconds; both pulps were stored at 40 °C. The anthocyanin content reduction in the drink was evaluated from the half-life time (t1/2), activation energy (Ea), temperature quotient (Q10), and the reaction rate constant (k). The t1/2 of the PLP anthocyanins stored at 40 °C was 1.8 times less than that stored at 25 °C and 15 times less than that stored at 0 °C; therefore, the higher temperatures decreased the stability of anthocyanins. The pasteurization increased the t1/2 by 6.6 times (10.14 hours for NPP and 67.28 hours for NPP-P). The anthocyanin degradation on NPP-P followed a first order kinetic, while NPP followed a second order kinetic; thus it can be said that the pasteurization process can improve the preservation of anthocyanins in the pulp.

scholarly journals Shelf Life Studies of Three Wasabi Flavoured Sauces

1970 ◽  
Vol 44 (2) ◽  
pp. 147-156
Author(s):  
Tamanna Sultana ◽  
GP Savage ◽  
NG Porter ◽  
DL McNeil ◽  
JR Sedcole
Keyword(s):  
Shelf Life ◽  
Storage Temperature ◽  
Initial Level ◽  
Tomato Sauce ◽  
Wasabia Japonica ◽  
Different Temperatures ◽  
Small Change ◽  
Shelf Life Studies ◽  
The Stability ◽  
Storage Temperatures

Isothiocyanates (ITCs) contained in purees extracted from wasabi (Wasabia japonica (Miq) Matsum) can be used to manufacture a range of interesting spicy foods. In New Zealand, local manufacturers are showing interest in producing various forms of processed wasabi based sauces. However, isothiocyanates have been shown to degrade quickly in some situations. Therefore, in this study, the stability of allyl ITC was investigated in three wasabi flavoured products stored at four different temperatures (4, 10, 20 and 30°C) for 22 weeks. Two creamy (mayonnaise and tartare) sauces and a non-creamy sauce were prepared from an original recipe and flavoured with a known volume of "wasabi oil". Two types of pouches (clear and metallic plastic) were used to store each product and allyl ITC content was measured in the stored sauces at two week intervals. The initial level of allyl ITC found in mayonnaise, tartare and smoky tomato sauces were 415.3, 411.4 and 144.7 mg/ kg respectively, prior to storage. Temperature showed a strong influence in reducing allyl ITC (P=0.005 to <0.001) but no significant effect was identified for the two types of packets used. The non-creamy smoky tomato sauce was very unstable at 10°C or higher temperatures and the allyl ITC contents reduced rapidly with increasing storage temperatures. For instance, at 30°C, a 66% loss occurred by week 2 and a 90% loss occurred by week 6 in the smoky tomato sauce. However, mayonnaise and tartare sauces had a shelf life of 8 to 9 weeks with only a marginal reduction in allyl ITC (2% overall) at all the stored temperatures (4-30°C). These creamy sauces were characterized by a sudden fall in 10 weeks ending in a 69-70% loss of allyl ITC at 22 weeks. No microbial growth occurred in any of the sauces stored at any of the temperatures during the course of this storage experiment though very small change of colour was noticed for the sauces when stored at 30°C. Keywords: Bangladesh J. Sci. Ind. Res. 44(2), 147-156, 2009DOI: 10.3329/bjsir.v44i2.3665Bangladesh J. Sci. Ind. Res. 44(2), 147-156, 2009

Stability of Enterocin AS-48 in Fruit and Vegetable Juices

2005 ◽  
Vol 68 (10) ◽  
pp. 2085-2094 ◽  
Author(s):  
MARIA J. GRANDE ◽  
ROSARIO LUCAS ◽  
EVA VALDIVIA ◽  
HIKMATE ABRIOUEL ◽  
MERCEDES MAQUEDA ◽  
...  
Keyword(s):  
Storage Temperature ◽  
Fruit Juices ◽  
Initial Activity ◽  
Fruit And Vegetable ◽  
Bacteriocin Activity ◽  
Green Beans ◽  
Food Components ◽  
Fruit And Vegetable Juices ◽  
The Stability ◽  
Thickening Agents

Enterocin AS-48 is a candidate bacteriocin for food biopreservation. Before addressing application of AS-48 to vegetable-based foods, the interaction between AS-48 and vegetable food components and the stability of AS-48 were studied. Enterocin AS-48 had variable interactions with fruit and vegetable juices, with complete, partial, or negligible loss of activity. For some juices, loss of activity was ameliorated by increasing the bacteriocin concentration, diluting the juice, or applying a heat pretreatment. In juices obtained from cabbage, cauliflower, lettuce, green beans, celery, and avocado, AS-48 was very stable for the first 24 to 48 h of storage under refrigeration, and decay of activity was markedly influenced by storage temperature. In fresh-made fruit juices (orange, apple, grapefruit, pear, pineapple, and kiwi) and juice mixtures, AS-48 was very stable for at least 15 days at 4°C, and bacteriocin activity was still detectable after 30 days of storage. Gradual and variable loss of activity occurred in juices stored at 15 and 28°C; inactivation was faster at higher temperatures. In commercial fruit juices (orange, apple, peach, and pineapple) stored at 4°C, the bacteriocin was completely stable for up to 120 days, and over 60% of initial activity was still present in juices stored at 15°C for the same period. Commercial fruit juices stored at 28°C for 120 days retained between 31.5% (apple) and 67.71% (peach) of their initial bacteriocin activity. Solutions of AS-48 in sterile distilled water were stable (120 days at 4 to 28°C). Limited loss of activity was observed after mixing AS-48 with some food-grade dyes and thickening agents. Enterocin AS-48 added to lettuce juice incubated at 15°C reduced viable counts of Listeria monocytogenes CECT 4032 and Bacillus cereus LWL1 to below detection limits and markedly reduced viable counts of Staphylococcus aureus CECT 976.

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