scholarly journals Banana liqueur made with yacon syrup: evaluation of stability during maturation

2021 ◽  
Vol 24 ◽  
Author(s):  
Leandro Levate Macedo ◽  
Wallaf Costa Vimercati ◽  
Cintia da Silva Araújo ◽  
Antonio Manoel Maradini Filho ◽  
Sérgio Henriques Saraiva ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Room Temperature ◽  
Color Difference ◽  
Maturation Time ◽  
Alcohol Content ◽  
Time Zero ◽  
The Stability ◽  
And Storage ◽  
Total Color Difference

Abstract The aim of this work was to evaluate the stability during maturation of banana liqueurs made with yacon syrup and sucrose. Thus, 20 °GL and 30 °Brix liqueurs were produced using yacon and sucrose syrups at concentrations of 42.8 and 45.0 °Brix. The liqueurs were subjected to two procedures as following: heat treatment at 70 °C for 20 min (tranchage), followed by storage at room temperature for 10 days (T42-T and T45-T); no heat treatment and storage at 50 °C for 10 days (T42-50 and T45-50). The color and turbidity of liqueurs were evaluated daily within 10 days of storage. The alcohol content was evaluated every 2 days. The total color difference (ΔE) was calculated in relation to color at time zero for each treatment. The T42-50 treatment had the lowest turbidity at the end of maturation. The T45-T treatment presented the lowest ΔE value at the end of maturation. The alcohol contents regarding the liqueurs were the same as those contents after elaboration as well as did not change over the maturation time for all treatments.

The stability of acid-soluble chromosomal proteins from avian erythrocytes

1968 ◽  
Vol 46 (8) ◽  
pp. 781-788 ◽  
Author(s):  
G. Vidali ◽  
J. M. Neelin
Keyword(s):  
Acetic Acid ◽  
Room Temperature ◽  
Starch Gel Electrophoresis ◽  
Guanidinium Chloride ◽  
Chromosomal Proteins ◽  
Avian Erythrocytes ◽  
Starch Gel ◽  
Avian Erythrocyte ◽  
The Stability ◽  
And Storage

The stability of avian erythrocyte histones was examined under the conditions of extraction, chromatography, electrophoresis, and storage, in order to avoid degradation during these operations. Since turbidity in trichloroacetic acid (TCA) was used as a measure of histone integrity, optimal conditions for quantitative assay were established as follows. One volume of histone sample was mixed with five volumes of 1.1 M TCA at room temperature, and the optical density at 400 mμ was measured after 25 min. The relation between turbidity and protein concentration was linear from 0.03 to at least 0.3 mg histone per milliliter and was not related to the kind of histone, except for the lysine-rich fraction which showed slightly less specific turbidity. Under these conditions turbidity was not sensitive to concomitant solutes such as guanidinium chloride, acetic acid, and dilute buffers and acids.With turbidity as the criterion of protein integrity, it was confirmed that brief manipulation in the cold is desirable in most media, including the dilute acids used for extraction. Nevertheless, chromatography at room temperature in concentrated solutions of guanidinium chloride or acetic acid appears to be tolerably safe. The effect of these conditions of manipulation and storage on histone fractions was substantiated by chromatography and starch-gel electrophoresis. Prolonged extraction of avian erythrocyte nuclei at acid pH released additional non-histone basic protein without alteration of authentic histone fractions.

scholarly journals Стабильность функциональных характеристик прозрачных электродов на основе трехслойной структуры ZnO : Ga/Ag/ZnO : Ga

2022 ◽  
Vol 48 (2) ◽  
pp. 51
Author(s):  
А.Ш. Асваров ◽  
А.К. Ахмедов ◽  
А.Э. Муслимов ◽  
В.М. Каневский
Keyword(s):  
Heat Treatment ◽  
Thermal Stability ◽  
Room Temperature ◽  
Layer Structure ◽  
Visible Range ◽  
Practical Application ◽  
Transparent Conducting ◽  
Average Transmittance ◽  
The Stability

Since to the stability of the functional properties of a transparent conducting three-layer structure ZnO:Ga/Ag/ZnO:Ga is important for practical application, we studied its long-term durability and thermal stability in air environment. It has been demonstrated that after prolonged interaction with the air environment at room temperature (~ 1000 h) and further heat treatment in air at temperatures up to 450 ° C (up to 10 h), the three-layer structure retains its integrity and is characterized by a low sheet resistance Rs = 2.8 Ω/sq at average transmittance in the visible range Tav of 82.1%.

Factors affecting measurement of urinary oxalate.

1984 ◽  
Vol 30 (8) ◽  
pp. 1339-1343 ◽  
Author(s):  
B C Mazzachi ◽  
J K Teubner ◽  
R L Ryall
Keyword(s):  
Ascorbic Acid ◽  
Room Temperature ◽  
Alkaline Ph ◽  
Ascorbic Acid Concentration ◽  
Factors Affecting ◽  
The Stability ◽  
Gas Chromatographic Method ◽  
And Storage ◽  
Urine Specimens ◽  
Positive Interference

Abstract Using a gas-chromatographic method, we examined the effects of phosphate concentration, added calcium chloride, and pH on precipitation of oxalate from urine. All three factors are important, but the pH of precipitation is particularly so, especially in the presence of even normal concentrations of ascorbic acid. At pH 8, increases in measured oxalate ranged from 20% at an ascorbic acid concentration of 1 mmol/L to more than 300% at 15 mmol/L. Ascorbic acid is rapidly converted to oxalate at alkaline pH. We also investigated the stability of both untreated and acidified urine containing ascorbic acid during storage for up to one month at -70, -20, and 4 degrees C, and room temperature. After one month, untreated collections were stable at -70 degrees C and acidified collections at -20 and -70 degrees C. We recommend conditions for assay and storage of urine specimens that are to be assayed for oxalate under which positive interference by ascorbic acid is minimized.

scholarly journals Stability of hepatitis B virus pregenomic RNA in plasma specimens under various temperatures and storage conditions

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11207
Author(s):  
Pakkapon Rattanachaisit ◽  
Sirinporn Suksawatamnuay ◽  
Supachaya Sriphoosanaphan ◽  
Kessarin Thanapirom ◽  
Panarat Thaimai ◽  
...  
Keyword(s):  
Hepatitis B Virus ◽  
Hepatitis B ◽  
Room Temperature ◽  
Plasma Samples ◽  
Freeze Thaw ◽  
B Virus ◽  
The Mean ◽  
Clinically Significant ◽  
The Stability ◽  
And Storage

Background Hepatitis B virus (HBV) pregenomic RNA (pgRNA) has gained increasing attention owing to its role in replication of covalently closed circular DNA (cccDNA) in HBV. This marker has the potential to be used in clinical programs aimed to manage HBV infections. However, several reports on HBV pgRNA levels in clinical cases have conflicting results. RNA is easily degraded when exposed to heat and other environmental stressors. However, the stability of HBV pgRNA, during blood sample collection before the standard automated quantification, has never been estimated. This study aimed to demonstrate the effect of two different temperature conditions and storage durations on the stability of HBV pgRNA. Method Blood from forty patients with chronic hepatitis B infection, who also showed evidence of active HBV DNA replication, was collected and processed within 2 h of collection. Plasma from each patient was divided and stored at 4 °C and 25 °C (room temperature) for six different storage durations (0, 2, 6, 12, 24, and 48 h) and subsequently transferred to −80 °C for storage. The effect of multiple cycles of freezing and thawing of plasma at −20 °C or −80 °C was evaluated using samples from ten patients. Quantification of pgRNA from the samples was performed simultaneously, using the digital polymerase chain reaction (dPCR) method. The differences in pgRNA levels at baseline and each time point were compared using generalized estimating equation (GEE). A change greater than 0.5 log10 copies/mL of pgRNA is considered clinically significant. Statistical analyses were conducted using Stata 16.0. Results The mean HBV pgRNA level in the initially collected plasma samples was 5.58 log10copies/mL (ranging from 3.08 to 8.04 log10 copies/mL). The mean pgRNA levels in samples stored for different time periods compared with the initial reference sample (time 0) significantly decreased. The levels of pgRNA for 6, 12, 24, and 48 h of storage reduced by −0.05 log10 copies/mL (95% confidence interval (CI) −0.095 to −0.005, p = 0.03), −0.075 log10 copies/mL (95% CI [−0.12 to −0.03], p = 0.001), −0.084 log10 copies/mL (95% CI [−0.13 to −0.039], p =  < 0.001), and −0.120 log10 copies/mL (95% CI [−0.17 to −0.076], p =  < 0.001), respectively. However, these changes were below 0.5 log10 copies/mL and thus were not clinically significant. Compared with the samples stored at 4 °C, there were no significant differences in pgRNA levels in samples stored at 25 °C for any of the storage durations (−0.01 log10 copies/mL; 95% CI [−0.708 to 0.689], p = 0.98). No significant difference in the levels of pgRNA was observed in the plasma samples, following four freeze-thaw cycles at −20 °C and −80 °C. Conclusion The plasma HBV pgRNA level was stable at 4 °C and at room temperature for at least 48 h and under multiple freeze-thaw cycles. Our results suggest that pgRNA is stable during the process of blood collection, and therefore results of pgRNA quantification are reliable.

scholarly journals Evaluation of an ELISA for metanephrines in feline urine

2018 ◽  
Vol 30 (6) ◽  
pp. 887-893
Author(s):  
Thanikul Srithunyarat ◽  
Anna Svensson ◽  
Sofia Hanås ◽  
Odd V. Höglund ◽  
Ragnvi Hagman ◽  
...  
Keyword(s):  
Neuroendocrine Tumors ◽  
Home Environment ◽  
Human Urine ◽  
Room Temperature ◽  
Storage Time ◽  
Stability Study ◽  
Urine Samples ◽  
Urine Sampling ◽  
The Stability ◽  
And Storage

Catecholamines can be used to evaluate neuroendocrine tumors, stress, and potentially pain, but catecholamines degrade rapidly. Their metabolites normetanephrine (NME) and metanephrine (ME) have better stability in urine. In cats, urine sampling in a home environment would be beneficial to reduce effects of clinical stress and simplify sampling. We evaluated a human urine ELISA for analysis of NME and ME in feline urine, and investigated the effects of acidification, cat tray pellets, and storage time at room temperature up to 8.5 h. In 26 feline urine samples, mean NME concentration was 192 ± 80 ng/mL, mean intra- and inter-assay CV was 6.5% and 4.2%, respectively, and spike recovery was 98–101%, but dilutional recovery was unsatisfactory. For ME, mean intra- and inter-assay CV was 10.2% and 4.1%, respectively. Mean urine ME concentration was 32.1 ± 18.3 ng/mL, close to the kit’s lowest standard, and spike recovery was 65–90%; the ELISA could not be validated for ME. The stability study, performed for NME on 12 urine samples, did not identify differences between acidified and non-acidified samples, cat tray pellets, or storage time, and no interaction effects. The ME ELISA was not suitable for feline urine; performance of the NME ELISA was acceptable, except for dilution recovery. For analysis of NME, feline urine can be sampled at home using cat tray pellets and stored at room temperature up to 8.5 h without acidification.

scholarly journals Effects of pH and Storage Time on the Stability of Papaya and Carrot Extracts

2019 ◽  
Vol 1 (1) ◽  
pp. 25
Author(s):  
Juliana Juliana ◽  
Renny Indrawati ◽  
Leny Yuliati
Keyword(s):  
Color Difference ◽  
Alkaline Condition ◽  
Natural Pigments ◽  
Treatment Conditions ◽  
Effects Of Ph ◽  
Color Degradation ◽  
The Stability ◽  
And Storage ◽  
Freeze Dryer ◽  
Better Than

Papaya and carrot are rich in natural pigments, especially b-carotene. Unfortunately, in most cases, natural pigments are less stable than the synthetic ones when they are put in a variety of treatment conditions, such as pH. In this work, the stability of the papaya and carrot extracts were evaluated in various pH, which ranges of 1-10 for 7 days. The extracts were obtained by a slow juicer, followed by encapsulation and drying by a freeze dryer. The extracts were then dispersed in buffer solutions and the chroma and color difference (DE) values were calculated from the obtained lightness (L*), redness (a*), and yellowness (b*). The results showed that carrot extract was better than the papaya extract in terms of chroma values. It was also shown that both extracts were not stable under acidic condition, but more stable in neutral to alkaline condition. The acid condition facilitated the cleavage of the conjugated bonds in the b-carotene, which in turn caused the color degradation in the papaya and carrot extracts.

scholarly journals Microcapsules of ‘jabuticaba’ byproduct: Storage stability and application in gelatin

2018 ◽  
Vol 22 (6) ◽  
pp. 424-429 ◽  
Author(s):  
Leticia M. Rodrigues ◽  
Jaqueline G. B. Januário ◽  
Suelen S. dos Santos ◽  
Rita Bergamasco ◽  
Grasiele S. Madrona
Keyword(s):  
Phenolic Compounds ◽  
Xanthan Gum ◽  
Storage Stability ◽  
Color Stability ◽  
Color Difference ◽  
Adverse Conditions ◽  
Gelatin Sample ◽  
The Stability ◽  
Total Color Difference ◽  
Monomeric Anthocyanins

ABSTRACT This study aimed to produce microcapsules using ‘jabuticaba’ byproduct through lyophilization, and evaluate the stability of the powder, intended for use in gelatin. Three formulations were prepared, including the pure lyophilized extract (E), capsule with maltodextrin (CapM), and capsule with maltodextrin and xanthan gum (CapMG). The storage stability was evaluated at 4 and 25 ºC, and in the presence and absence of light, regarding color parameters, phenolic compounds and monomeric anthocyanins. The microencapsulated powders were applied in gelatin and analyzed for sensorial acceptance. Following an investigation of the storage stability of the three powders at 4 °C for 60 days, the sample that presented the best result was then analyzed at 25 ºC in the presence/absence of light. Microcapsules, independent of the encapsulant agent, exhibited lower values of degradation (2.82% phenolic compounds and 14.5% monomeric anthocyanins) than extract E when exposed to light and at 25 °C. Regarding color stability, CapMG showed smaller variations in the total color difference (ΔE) than the other samples. The lowest ΔE value corresponded to the gelatin sample with CapM, stored in the absence of light. It is possible to conclude that microencapsulation is an alternative for the preservation of ‘jabuticaba’ byproduct extracts, facilitating their use, retaining some compounds and protecting them against adverse conditions.

Human plasma stability during handling and storage: impact on NMR metabolomics

The Analyst ◽  
2014 ◽  
Vol 139 (5) ◽  
pp. 1168-1177 ◽  
Author(s):  
Joana Pinto ◽  
M. Rosário M. Domingues ◽  
Eulália Galhano ◽  
Cristina Pita ◽  
Maria do Céu Almeida ◽  
...  
Keyword(s):  
Human Plasma ◽  
Room Temperature ◽  
Storage Conditions ◽  
Plasma Composition ◽  
Long Term Storage ◽  
Short And Long Term ◽  
The Stability ◽  
And Storage ◽  
Term Storage

The stability of human plasma composition was investigated by NMR, considering different collection tubes, time at room temperature (RT), short- and long-term storage conditions and up to 5 consecutive freeze–thaw cycles.

scholarly journals Stability of lactoferrin and lysozyme in human milk at various temperatures and duration of storage

2021 ◽  
Vol 27 (2) ◽  
Author(s):  
◽  
Sumirah Budi Pertami ◽  
Agus Setyo Utomo ◽  
Siti Nur Arifah ◽  
◽  
...  
Keyword(s):  
Human Milk ◽  
Room Temperature ◽  
Storage Time ◽  
Enzyme Linked Immunosorbent Assay ◽  
Milk Samples ◽  
Duration Of Storage ◽  
Different Temperatures ◽  
Bioactive Content ◽  
The Stability ◽  
And Storage

Introduction: Exclusive breastfeeding, especially in the first six months, is essential for infants as it provides nutrition and protection against various diseases. Colostrum, which is found in the first breast milk produced, contains various protective factors, such as lactoferrin and lysozyme. Human milk can be stored at room temperature, refrigerated, or kept frozen. Several factors affect the stability of the bioactive content in human milk, such as temperature and storage time. The aim of this study was to measure the stability of lactoferrin and lysozyme levels in human milk during the first six hours (h) at different temperatures and compare it with that of frozen human milk. Methods: Human milk samples were obtained from 11 breastfeeding mothers using certain criteria. The human milk was stored at room temperature and 4°C for 1, 3, and 6 h and classified as never frozen, while frozen human milk was stored at -20°C for 1, 3, and 6 days. Measurement of the lactoferrin and lysozyme levels was performed using enzyme-linked immunosorbent assay. Results: The results showed that storage at room temperature significantly reduced lactoferrin and lysozyme levels. Lactoferrin levels in frozen human milk did not significantly decrease during the first six days. Meanwhile, the lysozyme levels in frozen human milk decreased significantly. Conclusion: The levels of lactoferrin and lysozyme in frozen human milk stored for the first six days were more stable than those stored at room temperature and 4°C in the first 6 h.

scholarly journals Stability of Eleutherine americana (L.) Merr. Extract as Lipstick Colorants as the Change of Temperature, Time, Storage Condition and the Presence of Oxidator

2018 ◽  
Vol 5 (1) ◽  
pp. 8 ◽  
Author(s):  
Dewi Mayasari ◽  
Taofik Rusdiana ◽  
Yulien Ratu Kania ◽  
Marline Abdassah
Keyword(s):  
Room Temperature ◽  
Storage Condition ◽  
Stability Test ◽  
C 50 ◽  
The Stability ◽  
And Storage ◽  
Temperature Time ◽  
Color Pigment ◽  
Eleutherine Americana ◽  
Temperature Storage

Bawang Tiwai (Eleutherine americana (L.) Merr bulbus. is a typical plant from Kutai tribes which commonly used as an anti-bacterial and food coloring. The stability test is performed to determine the stability of the extract. Stability test was conducted in two solvents are distilled water and ethanol include the effects of temperature (25°C, 50°C, 80°C), pH (3, 5, 7), an oxidant for 6 hours, conditions of storage at room temperature and the temperature of the refrigerator for 24 hours and storage for 2 weeks. The absorbance of extract in ethanol and aquadest was decreasing due to the change of temperature, time, the presence of oxidator but due to pH changes, the absorbance of extract was increasing. Meanwhile, on the storage condition, showed the highest absorbance on dark, and room temperature storage compared to other condition.Key words: Eleutherine americana (L.) Merr bulbus, stability, color pigment

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