scholarly journals The Effect of Initial Purity on the Stability of Solutions in Storage

2013 ◽  
Vol 19 (2) ◽  
pp. 308-316 ◽  
Author(s):  
Ioana Popa-Burke ◽  
Steven Novick ◽  
Charles A. Lane ◽  
Robin Hogan ◽  
Pedro Torres-Saavedra ◽  
...  

Many modern compound-screening technologies are highly miniaturized, resulting in longer-lasting solution stocks in compound management laboratories. As the ages of some stocks stretch into years, it becomes increasingly important to ensure that the DMSO solutions remain of high quality. It can be a burden to check the quality of a large library of compound solutions continuously, and so a study was devised to link the effects of initial compound purity and physicochemical properties of the compounds with the current purity of DMSO solutions. Approximately 5000 compounds with initial purity of at least 80% were examined. Storage conditions were held or observed to be relatively constant and so were eliminated as potential predictors. This allowed the evaluation of the effects of other factors on the stability of solutions, such as initial purity, number of freeze-thaw cycles, age of the solution, and multiple calculated physicochemical parameters. Of all the factors investigated, initial purity was the only one that had a clear effect on stability. None of the other parameters investigated (physicochemical properties, number of freeze-thaw cycles, age of solutions) had a statistically significant effect on stability.

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 374
Author(s):  
Teresa Szczęsna ◽  
Ewa Waś ◽  
Piotr Semkiw ◽  
Piotr Skubida ◽  
Katarzyna Jaśkiewicz ◽  
...  

The aim of this study was to determine the influence of storage temperature and time on physicochemical parameters of starch syrups recommended for the winter feeding of bee colonies. The studies included commercially available three starch syrups and an inverted saccharose syrup that were stored at different temperatures: ca. 20 °C, 10–14 °C, and ca. 4 °C. Physicochemical parameters of fresh syrups (immediately after purchase) and syrups after 3, 6, 9, 12, 15, 18, 21, and 24 months of storage at the abovementioned temperatures were measured. It was observed that the rate of unfavorable changes in chemical composition of starch syrups and the inverted saccharose syrup, mainly the changes in the 5-hydroxymethylfurfural (HMF) content, depended on the type of a syrup and storage conditions (temperature, time). Properties of tested starch syrups intended for winter feeding of bees stored at ca. 20 °C maintained unchanged for up to 6 months, whereas the same syrups stored at lower temperatures (10–14 °C) maintained unchanged physicochemical parameters for about 12 months. In higher temperatures, the HMF content increased. To date, the influence of this compound on bees has not been thoroughly investigated.


2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Driss Ousaaid ◽  
Hamada Imtara ◽  
Hassan Laaroussi ◽  
Badiaa Lyoussi ◽  
Ilham Elarabi

Vinegar is a natural product rich in bioactive compounds such as phenols, flavonoids, and organic acids. Several factors affect the quality of vinegars such as apple origin, environmental conditions, production methods, processing, and storage conditions. We investigated the quality of apple vinegars as well as their physicochemical properties and the antioxidant and antibacterial activities of vinegars collected from different areas in Morocco. For physicochemical properties, the outcomes showed the following values: pH (3.18–3.83), electrical conductivity (2.11–2.90), acidity (0.24–5.6), Brix (3.25–6), and density (1.0123–1.0233). The polyphenols content of samples was 68.91 mg AG/100 mL in sample S6 as the minimum value and 147.54 mg AG/100 mL in sample S2 as the maximum value. The best ability to scavenge the DPPH radical was observed in sample S3 (IC50 = 0.45 ± 0.013 µL/mL). Sample S2 showed moderate antibacterial effect against microorganisms tested with MICs ranging from 0.78 µL/mL to 1.125 µL/mL and with a diameter of inhibition ranging from 15.65 mm to 27.65 mm. In addition, a strong correlation was observed between the antibacterial activity of vinegars and physicochemical parameters (pH and total acidity). These outcomes have shown that our vinegar samples are an excellent source of bioactive compounds with potent antioxidant and antibacterial potentials.


2018 ◽  
Vol 26 (2) ◽  
pp. 165 ◽  
Author(s):  
Zhaoming Wang ◽  
Z. He ◽  
Hongjun Li

<p>We investigated the effect of repeated freeze-thaw cycles on the quality of rabbit meat. Twenty-five Hyla rabbits were slaughtered using standard commercial procedures. A freeze-thaw procedure—i.e., seven days frozen at –18°C followed by thawing at 4°C for 12h— was repeated 5 times, and 9 <em>Longissimus thoracis et lumborum</em> muscles were randomly selected at pre-set cycles (0, 1, 2, 3, and 5). The <em>Longissimus lumborum</em> muscles were used to determine meat quality parameters, while the <em>Longissimus thoracis</em> muscles were used for chemical analysis. During the repeated freeze-thaw process, muscle pH, redness, hardness, and water holding capacity gradually decreased, whereas meat lightness and yellowness gradually increased. The amount of total volatile basic nitrogen significantly increased (<em>P</em>&lt;0.05) and exceeded the threshold value for frozen meat after 5 repeated freeze-thaw cycles. The metmyoglobin proportion, thiobarbituric acid-reactive substances (TBARS) and protein carbonyl content in rabbit meat samples increased with a higher number of freeze-thaw cycles (<em>P</em>&lt;0.05), and the proportions of these compounds were positively correlated. During the repeated freeze-thaw process, extractable haeme iron levels significantly decreased (<em>P</em>&lt;0.05), and non-haeme iron levels markedly increased (<em>P</em>&lt;0.05). An sodium dodecyl sulfate polyacrylamide gel electrophoresis analysis indicated that the degradation of both water- and salt-soluble proteins was more prevalent in samples subjected to higher numbers of freeze-thaw cycles. Additionally, a principal component analysis identified good correlations between physicochemical properties (TBARS, protein carbonyl levels and metmyoglobin content) and quality parameters (thawing loss, redness, lightness and hardness). Taken together, we conclude that the repeated freeze-thaw process can strongly affect rabbit meat quality as well as its physicochemical properties.</p>


2021 ◽  
Vol 2049 (1) ◽  
pp. 012003
Author(s):  
Imron Meechai ◽  
Isma-ae Chelong ◽  
Romlee Chedoloh

Abstract Honey of stingless bee has a higher moisture content than bees. Long-term storage may cause fermentation processes to change the physicochemical properties and taste. Thus, the aim of this research was evaluation of the optimum storage condition on the quality of stingless bee honey. Stingless bee honey (Tetragonular larviceps) was contained in plastic bottle and kept at ambient temperature (30-35°C) and low temperature (4-8°C) for 0-45 days. Before and after storage honey were analyzed the physicochemical properties and sensory investigation for comparison of quality. The results showed that temperatures and storage times have affected on the reducing sugar content, pH, conductivity, color, moisture content with significant difference (p<0.05). While, temperatures and storage times have unaffected on the °Brix value (p>0.05). Additionally, the physicochemical properties of honey were according with previously quality report. The sensory investigation indicated that the smell natural flavor, consistency, taste and sourness were not significant difference (p>0.05). In contrast, the color and overall preference were significant difference (p<0.05). For honey quality, Thus, the honey might keep at 4-35°C for ≤45 day of this study.


2015 ◽  
Vol 7 (2) ◽  
pp. 99-109 ◽  
Author(s):  
Nadežda Prica ◽  
Milica Živkov Baloš ◽  
Sandra Jakšić ◽  
Željko Mihaljev ◽  
Brankica Kartalović ◽  
...  

The color, aroma and fl avor are major sensory characteristics of honey, which are mainly determined by the botanical origin of honey as well as by processing and storage conditions. Increased moisture content above the maximum permitted level could result in honey spoilage, which aff ects its sensory properties. The higher water-in-honey content, the greater possibility of yeast fermentation and thus the change of the fl avor and color ofhoney. Fermentation process results in alcohol formation and, in the presence of oxygen, the alcohol will break down to acetic acid and water, which causes honey to have sour taste. Thus, moisture content of honey is a critical parameter for its quality as it aff ects the stability of honey and its resistance to microbial spoilage during storage. Physicochemical analysis of moisture content and acidity of honey play an important role in determining the overall characteristic of honey and final assessment of its quality. In this study, the investigation of aforementioned parameters resulted in positive quality assessment for 48 of 50 examined honey samples produced in 2013 in the territory of Vojvodina.


2020 ◽  
Author(s):  
Zhuoling An ◽  
Chen Shi ◽  
Pengfei Li ◽  
Lihong Liu

AbstractAmino acids analysis or metabonomics requires abundant serum/plasma samples collection and samples storage has become inevitable given the limited capacity for immediate analysis. Currently, most of the existing studies on metabolites stability during sample storage focused on long-term and short-term stability, while many functional amino acids might be ignored due to the poor sensitivity and detection of analysis methods. Here, we attempted to elucidate the stability of amino acids and related amines as comprehensive as possible in human serum following different preprocessing and pre-storage procedures. Pooled, fasting serum samples were collected and stored at 4 °C and 22 °C respectively after a delay in sample processing (0, 1, 2, 4, 8, 12 and 24 hours) and underwent freeze-thaw cycles for three times at −80 °C. The concentration of amino acids and related amines were quantified using isobaric tagging reagent iTRAQ®-LC-MS/MS. Approximately 54.84 %, 58.06 % and 48.39 % of detectable and target analytes altered at 4 °C and 22 °C during pre-treatment and freeze-thaw cycles. Some amino acids which are not stable and relatively stable were found. Our study provided detailed profiles and suggestions for amino acids in human serum corresponding to diverse collection and pre-treatment measures.


Agronomy ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 134
Author(s):  
Ewa Szpadzik ◽  
Ewa Zaraś-Januszkiewicz ◽  
Tomasz Krupa

The consumer acceptability of the fruit is very important aspect of distribution. Consumers expect high-quality fruit with high pro-health values. The intention of the research was to assess the quality of hardy kiwi fruit changes during storage in order to provide consumers with high-quality fruit and nutraceutical content. A particular challenge was to assess the storage capacity of the new Polish variety ‘Bingo’PBR. This is a protected Plant Breeder’s Right (PBR) cultivar in accordance with the Union Internationale pour la Protection des Obtentions Vegetates (UPOV). The storage quality of the fruit of the ‘Bingo’ cultivar was assessed in contrast to the fruit of the ‘Ananasnaya’ cultivar, the basic minikiwi cultivar. The experiment assessed the effect of the fruit ripeness phase during harvest (°Brix −7.7 and 9.0) and the effect of the storage conditions, i.e., normal atmosphere cold store (0.1% CO2: 21% O2) versus controlled atmosphere (1.5% CO2: 1.5% O2). In the fruit evaluation, the focus was concentrated on changes in the basic color of the peel, firmness, soluble solids content, acidity, as well as the main health-promoting attributes, i.e., antioxidant activity, vitamin C content and total polyphenols. In the experiment, it was found the fruits of ‘Ananasnaya’ variety were almost 40% harder than the fruits of ‘Bingo’PBR variety. The CA technology (1.5% CO2: 1.5% O2) allows for the acceptable firmness of the fruit for up to 56 days of storage. The earlier harvest with an extract content of 7.0–7.5°Brix also promotes higher fruit firmness. Fruits stored in a normal atmosphere cold store ripen faster and are fully ripe after 28 days. ‘Bingo’PBR variety is characterized by fruits with a higher ascorbic acid content than the fruits of ‘Ananasnaya’ variety. The vitamin C content in fruits increases up to 28 days, regardless of the conditions in which they are stored. The content of polyphenols does not change significantly during storage, which reflects the higher stability of these compounds in fruits.


Pharmaceutics ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1267
Author(s):  
Jumpei Saito ◽  
Nozomi Yoshikawa ◽  
Takehisa Hanawa ◽  
Ayuna Ozawa ◽  
Takahiro Matsumoto ◽  
...  

Hydrocortisone has been utilized in the management of adrenal insufficiency. For pediatric patients, the commercially available enteral form of hydrocortisone tablets (Cortoril®) is administered in powder form after being compounded by a pharmacist. However, the stability and quality of compounded hydrocortisone powder have not been verified. In this study, we formulated a 20 mg/g oral hydrocortisone powder by adding lactose monohydrate to crushed and filtered hydrocortisone tablets and assessed the stability and physical properties of this compounded product in polycarbonate amber bottles or coated paper packages laminated with cellophane and polyethylene. Stability was examined over 120 days in three storage conditions: closed bottle, in-use bottle, and laminated paper. Drug dissolution and powder X-ray diffraction analysis were conducted to assess its physicochemical stabilities. Validated liquid chromatography-diode array detection was used to detect and quantify hydrocortisone and its degradation products. Although impurity B (cortisone) and G (hydrocortisone-21-aldehyde) were found after 120 days of storage, no crystallographic and dissolution changes were noted. Hydrocortisone content was maintained between 90% and 110% of initial contents for 120 days at 25 ± 2 °C and 60 ± 5% relative humidity in all packaging conditions.


Foods ◽  
2021 ◽  
Vol 10 (8) ◽  
pp. 1945
Author(s):  
Soraya Mousavi ◽  
Roberto Mariotti ◽  
Vitale Stanzione ◽  
Saverio Pandolfi ◽  
Valerio Mastio ◽  
...  

The extent and conditions of storage may affect the stability and quality of extra virgin olive oil (EVOO). This study aimed at evaluating the effects of different storage conditions (ambient, 4 °C and −18 °C temperatures, and argon headspace) on three EVOOs (low, medium, and high phenols) over 18 and 36 months, analyzing the main metabolites at six time points. The results showed that low temperatures are able to maintain all three EVOOs within the legal limits established by the current EU regulations for most compounds up to 36 months. Oleocanthal, squalene, and total phenols were affected by storage temperatures more than other compounds and degradation of squalene and α-tocopherol was inhibited only by low temperatures. The best temperature for 3-year conservation was 4 °C, but −18 °C represented the optimum temperature to preserve the organoleptic properties. The present study provided new insights that should guide EVOO manufacturers and traders to apply the most efficient storage methods to maintain the characteristics of the freshly extracted oils for a long conservation time.


Author(s):  
N. Azzouzi ◽  
S. Zantar ◽  
N. Aghmir ◽  
M.R. Britel ◽  
A. Maurady

Background: Blackberry is a seasonal harvested fruit that is also very fragile and perish- es quickly. A comparative study was conducted to find out influence of cold storage on physicochemical parameters of wild and cultivated blackberry over a period of 12 days. Methods: The plant materials were composed of the blackberry fruit, including a compound of cultivated blackberry (Rubus spp.), and wild blackberry (Rubus fruticosus L. agg) which were harvested in the North of Morocco. The temperature of the storage of wild and cultivated blackberry was 5 °C for 4, 8, and 12 days, and then transferred to 25 °C for 1 day to simulate transport and commercialization. After that, the physicochemical parameters were analyzed. Statistical analyses were performed using SAS. Results: During 12 days of storage, the pH of samples was decreased from 3.69 to 3.22 for wild blackberry, and from 4.85 to 3.43 for cultivated blackberry. The titratable acidity was increased from 1.61 to 3.28 for wild blackberry, and from 2.07 to 3.25 for cultivated blackberry. Flavonoids also showed a remarkable increase in values from 30 to 70.66 mg QE/100g of wild blackberries and from 25.33 to 60.66 mg QE/100g in cultivated ones between harvest and the last day of storage. The variation in skin color revealed a decrease during storage of L* brightness, a* redness, and yellowness b* for both blackberries. Conclusion: The most suitable storage time of blackberry components during cold storage at 5 °C was 12 days. The temperature at 5 °C preserves the quality of the blackberry for both wild and cultivated ones. However, the wild blackberry was more resistant than cultivated one to cold storage.


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