scholarly journals Changes of Physicochemical Properties of Starch Syrups Recommended for Winter Feeding of Honeybees during Storage

Agriculture ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 374
Author(s):  
Teresa Szczęsna ◽  
Ewa Waś ◽  
Piotr Semkiw ◽  
Piotr Skubida ◽  
Katarzyna Jaśkiewicz ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Physicochemical Properties ◽  
Physicochemical Parameters ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Different Temperatures ◽  
And Storage ◽  
Bee Colonies ◽  
Temperature Time ◽  
Winter Feeding

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.

scholarly journals Textural Changes of Asparagus in Relation to Delays in Cooling and Storage Conditions

1992 ◽  
Vol 2 (3) ◽  
pp. 378-381 ◽  
Author(s):  
Luis Hernández-Rivera ◽  
Robert Mullen ◽  
Marita Cantwell
Keyword(s):  
Shear Force ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Asparagus Officinalis ◽  
Shear Transfer ◽  
Textural Changes ◽  
And Storage ◽  
Temperature Time ◽  
Storage Temperatures

Asparagus (Asparagus officinalis L.) spears (cv. UC 157) trimmed to 20 cm were cooled 0, 4, 8, 12, 16, and 20 hours after harvest and evaluated for resistance to shear at 5 and 10 cm above the cut end immediately after cooling and during storage at 0.5, 2.5, and 5C. Resistance to shear increased during cooling delays and with time in storage. Initial cooling delays and simulated marketing conditions (transfer to 15C for 1 day) were the principal causes of increased resistance to shear. A 4-hour cooling delay resulted in an average 40% increase in resistance to shear. Transfer to 15C for 1 day resulted in a greater increase in shear force in the rapidly cooled than in the delayed-cooled spears. Increases in resistance to shear during storage varied from 0% to 50% and depended on the storage temperature, time, and the initial cooling delay. Spears trimmed to a green base showed less increase in shear force after storage than did spears trimmed to a white base. The visual quality of asparagus stored for 14 days was similar (excellent) among spears from different storage temperatures and between green- and white-base spears. Storage quality after 24 days had decreased more in spears stored at 5C than at 2.5 or 0.5C, and more in the green-base than the white-base spears.

scholarly journals Preservation of Azotobacter chroococcum vegetative cells in dry polymers

2014 ◽  
Vol 20 (2) ◽  
pp. 201 ◽  
Author(s):  
Daniel Rojas-Tapias ◽  
Oriana Ortega Sierra ◽  
Diego Rivera Botía ◽  
Ruth Bonilla
Keyword(s):  
Storage Conditions ◽  
Azotobacter Chroococcum ◽  
Bacterial Degradation ◽  
Protective Agent ◽  
Degradation Rates ◽  
Different Temperatures ◽  
And Storage ◽  
Temperature Time ◽  
Long Term Preservation

We studied the preservation of Azotobacter chroococcum C26 using three dry polymers: carrageenin, sodium alginate, and HPMC, using a method of accelerated degradation. Bacterial viability, as response variable, was measured at three temperatures in four different times, which was followed by calculation of bacterial degradation rates. Results showed that temperature, time of storage, and protective agent influenced both viability and degradation rates (P;lt;0.05). We observed, using the Arrhenius thermodynamic model, that the use of polymers increased the activation energy of bacterial degradation compared to control. We obtained thermodynamic models for each polymer, based on the Arrhenius equation, which predicted the required time for thermal degradation of the cells at different temperatures. Analysis of the models showed that carrageenin was the best polymer to preserve A. chroococcum C26 since ~ 900 days are required at 4 ºC to reduce its viability in two log units. We conclude, therefore, that long-term preservation of A. chroococcum C26 using dry polymers is suitable under adequate preservation and storage conditions.

scholarly journals Influence of Alcohol Content and Storage Conditions on the Physicochemical Stability of Spirit Drinks

Foods ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 1264
Author(s):  
Mateusz Różański ◽  
Katarzyna Pielech-Przybylska ◽  
Maria Balcerek
Keyword(s):  
Volatile Compounds ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Deionized Water ◽  
Higher Alcohols ◽  
Alcohol Content ◽  
C Storage ◽  
Physicochemical Stability ◽  
Different Temperatures ◽  
And Storage

The purpose of this study was to investigate the effects of alcohol by volume (ABV) and storage temperature on changes in the clarity of rye and plum distillates, and their content of volatile compounds. Distillates with initial ABVs of 93.26% v/v (rye distillate) and 82.03% v/v (plum distillate) were diluted with deionized water to 40, 50, and 70% v/v. The samples were stored in darkness at different temperatures (−18 °C, 0 °C, 8 °C, 20 °C) for 8 weeks. The results showed that reducing the alcohol content and storage temperature caused turbidity to increase. The samples prepared from rye distillate were characterized by significantly lower turbidity than those produced from plum distillate. The highest increase in turbidity in comparison to the controls was observed in the samples with 40% v/v alcohol content stored at a temperature of −18 °C. Storage of the rye and plum distillates samples at different temperatures resulted in changes to the concentrations of volatile compounds, i.e., lower levels of acetaldehyde and higher alcohols, and increased content of esters. However, the alcohol content and storage temperature had no statistically significant effect on methanol concentration.

scholarly journals Effect of sweetener combination and storage temperature on physicochemical properties of sucrose free white chocolate

2017 ◽  
Vol 229 ◽  
pp. 610-620 ◽  
Author(s):  
Laura T. Rodriguez Furlán ◽  
Yanina Baracco ◽  
Javier Lecot ◽  
Noemi Zaritzky ◽  
Mercedes E. Campderrós
Keyword(s):  
Physicochemical Properties ◽  
Storage Temperature ◽  
And Storage

scholarly journals Influence of Different Filling, Cooling, and Storage Conditions on the Growth of Alicyclobacillus acidoterrestris CRA7152 in Orange Juice

2009 ◽  
Vol 75 (23) ◽  
pp. 7409-7416 ◽  
Author(s):  
Ana Cláudia N. F. Spinelli ◽  
Anderson S. Sant'Ana ◽  
Salatir Rodrigues-Junior ◽  
Pilar R. Massaguer
Keyword(s):  
Orange Juice ◽  
Storage Temperature ◽  
Growth Parameters ◽  
Storage Conditions ◽  
Inoculum Level ◽  
Alicyclobacillus Acidoterrestris ◽  
Time Required ◽  
Cold Point ◽  
And Storage ◽  
A Current

ABSTRACT The prevention of spoilage by Alicyclobacillus acidoterrestris is a current challenge for fruit juice and beverage industries worldwide due to the bacterium's acidothermophilic growth capability, heat resistance, and spoilage potential. This study examined the effect of storage temperature on A. acidoterrestris growth in hot-filled orange juice. The evolution of the A. acidoterrestris population was monitored under six different storage conditions after pasteurization (at 92°C for 10 s), maintenance at 85°C for 150 s, and cooling with water spray to 35°C in about 30 min and using two inoculum levels: <101 and 101 spores/ml. Final cooling and storage conditions were as follows: treatment 1, 30°C for the bottle cold point and storage at 35°C; treatment 2, 30°C for 48 h and storage at 35°C; treatment 3, 25°C for the bottle cold point and storage at 35°C; treatment 4, 25°C for 48 h and storage at 35°C; treatment 5, storage at 20°C (control); and treatment 6, filling and storage at 25°C. It was found that only in treatment 5 did the population remain inhibited during the 6 months of orange juice shelf life. By examining treatments 1 to 4, it was observed that A. acidoterrestris predicted growth parameters were significantly influenced (P < 0.05) either by inoculum level or cooling and storage conditions. The time required to reach a 104 CFU/ml population of A. acidoterrestris was considered to be an adequate parameter to indicate orange juice spoilage by A. acidoterrestris. Therefore, hot-filled orange juice should be stored at or below 20°C to avoid spoilage by this microorganism. This procedure can be considered a safe and inexpensive alternative to other treatments proposed earlier.

scholarly journals Determination of the Chemical Composition of Tea by Chromatographic Methods: A Review

2015 ◽  
Vol 4 (3) ◽  
pp. 56 ◽  
Author(s):  
Alexandr Ya Yashin ◽  
Boris V. Nemzer ◽  
Emilie Combet ◽  
Yakov I. Yashin
Keyword(s):  
Chemical Composition ◽  
Volatile Compounds ◽  
Black Tea ◽  
Storage Conditions ◽  
Organoleptic Evaluation ◽  
Chromatographic Methods ◽  
Tea Quality ◽  
Processing And Storage ◽  
And Storage

<p>Despite the fact that mankind has been drinking tea for more than 5000 years, its chemical composition has been studied only in recent decades. These studies are primarily carried out using chromatographic methods. This review summarizes the latest information regarding the chemical composition of different tea grades by different chromatographic methods, which has not previously been reviewed in the same scope. Over the last 40 years, the qualitative and quantitative analyses of high volatile compounds were determined by GC and GC/MS. The main components responsible for aroma of green and black tea were revealed, and the low volatile compounds basically were determined by HPLC and LC/MS methods. Most studies focusing on the determination of catechins and caffeine in various teas (green, oolong, black and pu-erh) involved HPLC analysis.</p> <p>Knowledge of tea chemical composition helps in assessing its quality on the one hand, and helps to monitor and manage its growing, processing, and storage conditions on the other. In particular, this knowledge has enabled to establish the relationships between the chemical composition of tea and its properties by identifying the tea constituents which determine its aroma and taste. Therefore, assessment of tea quality does not only rely on subjective organoleptic evaluation, but also on objective physical and chemical methods, with extra determination of tea components most beneficial to human health. With this knowledge, the nutritional value of tea may be increased, and tea quality improved by providing via optimization of the growing, processing, and storage conditions.</p>

scholarly journals An Investigation of Moroccan Vinegars: Their Physicochemical Properties and Antioxidant and Antibacterial Activities

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Driss Ousaaid ◽  
Hamada Imtara ◽  
Hassan Laaroussi ◽  
Badiaa Lyoussi ◽  
Ilham Elarabi
Keyword(s):  
Physicochemical Properties ◽  
Bioactive Compounds ◽  
Antibacterial Activities ◽  
Storage Conditions ◽  
Production Methods ◽  
Maximum Value ◽  
Processing And Storage ◽  
And Storage ◽  
Excellent Source

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.

scholarly journals Effect of storage temperature on Streptococcus mutans viability

2018 ◽  
Vol 47 (2) ◽  
pp. 74-78
Author(s):  
Ana Lídia Soares COTA ◽  
Ronaldo Gomes ALVIM
Keyword(s):  
Streptococcus Mutans ◽  
Storage Temperature ◽  
Storage Conditions ◽  
Descriptive Statistics ◽  
Bacterial Isolates ◽  
Future Studies ◽  
Long Period ◽  
Different Temperatures ◽  
Almost All ◽  
Microbiological Research

Abstract Introduction Proper storage conditions and maintenance of viable biological material plays an important role in microbiological research, allowing for the opportunity to conduct future studies. Objective To evaluate the viability of Streptococcus mutans strains that were previously grown and stored under different temperatures for approximately eight years. Material and method In this study, we evaluated 393 bacterial isolates that were stored in a freezer at -80°C (G1) and 200 isolates stored in a freezer at -20°C (G2). Aliquots of each sample were plated on blood agar and mitis-salivarius bacitracin sucrose agar-solidified medium. After incubating under microaerophilic conditions in an incubator at 37°C for 72 hours, the presence, morphology and purity of bacterial growth was observed. The data were analyzed by means of descriptive statistics. Result Microbial viability was observed in almost all samples (99.7%) in G1, whereas all isolates stored at -20°C were considered inviable. Conclusion The viability of S. mutans is influenced by the storage temperature of the samples, and the strains remain viable when stored under ideal temperature conditions (-80°C), even when stored for a long period of time.

California Almond Shelf Life: Changes in Moisture Content and Textural Quality During Storage

2019 ◽  
Vol 62 (3) ◽  
pp. 661-671 ◽  
Author(s):  
Jia Wu ◽  
Xiangyang Lin ◽  
Shengnan Lin ◽  
Paul Chen ◽  
Guangwei Huang ◽  
...  
Keyword(s):  
Relative Humidity ◽  
Moisture Content ◽  
Storage Temperature ◽  
Initial Moisture Content ◽  
Textural Properties ◽  
Storage Conditions ◽  
Temperature And Humidity ◽  
Lower Temperature ◽  
And Storage ◽  
Over Time

Abstract. The effects of packaging and storage conditions on the moisture content and instrumental and sensory textural properties of raw and salty light roasted (SLR) California almonds were studied under different storage conditions. The controlled combinations included low, medium, and high temperatures and low and high relative humidity (RH). Almond samples were packaged in cartons or polyethylene (PE) bags with and without vacuum. Both absorption and desorption of moisture by almonds were observed during storage and were dependent on the packaging and storage conditions. In general, gradual changes were observed for samples with PE and vacuum PE packaging in most of the storage conditions, while the samples packed in cartons showed more dramatic changes because these unprotected samples were more vulnerable to seasonal changes in humidity. The SLR almonds showed consistent moisture gains, while the raw almonds tended to lose moisture content in most of the storage conditions. This may be attributed to the low initial moisture content of the SLR samples. All raw samples packed in cartons became softer over time. The softening tended to be enhanced by high storage humidity and temperature. The raw almonds packaged in PE bags were firmer than those packed in cartons but also became softer over time. The firmness of the SLR samples was generally lower than that of raw samples, probably because roasting reduced the density and mechanical strength of the kernels. The firmness of PE packaged SLR samples increased in uncontrolled storage conditions and in higher storage temperature and humidity conditions but decreased slightly in lower temperature and humidity conditions. Vacuum packaging did not affect the firmness much. Using PE packaging and maintaining the RH below 50% and the temperature below 25°C are effective in stabilizing both raw and processed almonds. Keywords: Almond, Firmness, Nonpareil, Packaging, Relative humidity, Sensory, Storage, Temperature, Texture.

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