Kinetics of the Abiotic Oxidation of Hydrogen (H2) by Hematite at Subsurface Storage Conditions

Objective of the Work. The overview of current methodical approaches for experimental substantiation of the sell-by date of food products. Methods and Materials. Data analysis of scientific literature and normative documents on methods of substantiation of the sell-by date of food products. Results and Discussion. Sell-by date is a period since product’s manufacture, during which it maintains its safety and quality (including nutritional value) within reasonably foreseeable conditions of storage, distribution and consumption. In the case of new products (recipes) introduction it is necessary to review the sell-by date, and its extending as the need arises. The main aspects of microbiological substantiation of the sell-by date of food products are considered. The identification of microbial hazard for particular product is the first phase of the work. The second phase of the work is to determine the kinetic parameters of precise microorganism’s accumulation to maximum permitted level within regulated and aggravated conditions of product’s storage. Conclusions. In the process of microbiological substantiation of the sell-by date of food products it should be taken into consideration the presence of leading pathogen and causative microorganisms of microbial spoilage, the initial contamination level, the lag phase duration of germ culture development, variations between strains, the kinetics of microorganisms’ accumulation within the product in real and aggravated storage conditions, the indetermination connected with biological nature of microorganisms and their inhomogeneous allocation within the product, the limitation for shortcut research methods (if applicable). The decision rule should be based on the consumer’s risk concept. Key Words: food products, sell-by date, substantiation, microbiological indicators.

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Growth kinetics of Salmonella Typhimurium and Listeria monocytogenes in buffalo milk under different processing and storage conditions

Ciência Rural ◽

10.1590/0103-8478cr20200967 ◽

2021 ◽

Vol 51 (11) ◽

Author(s):

Joelson Sousa Lima ◽

Ana Paula Presley Oliveira Sampaio ◽

Mylla Christy da Silva Dufossé ◽

Paula Fernanda Morais de Sousa ◽

Josyane Brasil da Silva ◽

...

Keyword(s):

Listeria Monocytogenes ◽

Salmonella Typhimurium ◽

Growth Kinetics ◽

Storage Conditions ◽

Buffalo Milk ◽

Production Chain ◽

Pasteurized Milk ◽

Processing And Storage ◽

And Storage ◽

Kinetics Of

ABSTRACT: Buffalo milk is rich in nutrients and can serve as a substrate for the proliferation of microorganisms. Thus, the objective of the present study was to evaluate the growth kinetics of Salmonella Typhimurium and Listeria monocytogenes in buffalo milk under different processing and storage conditions. Samples of raw and pasteurized milk were inoculated with 1 CFU of each bacterium, separately and together, per 25 mL. After contamination, samples were stored at 8 °C or 37 °C, and bacterial counts were performed at 24, 48, and 168 h. In addition, the accompanying microbiota growth, pH, and the effect of these variables on the growth kinetics of microorganisms were monitored. The pathogens tested were able to proliferate under most conditions tested, reaching high titers throughout the experimental period. At 37 °C, there was a decrease in pH and an increase in the accompanying microbiota that interfered with the microbial growth curve. It was also observed that pasteurized milk subjected to 8 °C provided better conditions for the multiplication of bacteria. Therefore, it was concluded that care throughout the production chain, storage, and commercialization of milk must be adopted to guarantee the microbiological safety of this food.

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Kinetics of Ascorbic Acid Degradation in Un-Pasteurized Iranian Lemon Juice During Regular Storage Conditions

Pakistan Journal of Biological Sciences ◽

10.3923/pjbs.2008.1365.1369 ◽

2008 ◽

Vol 11 (10) ◽

pp. 1365-1369 ◽

Cited By ~ 5

Author(s):

Abbasi . ◽

M. Niakousari

Keyword(s):

Ascorbic Acid ◽

Storage Conditions ◽

Lemon Juice ◽

Acid Degradation ◽

Kinetics Of

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Application and Evaluation of a Pectin-Based Edible Coating Process for Quality Change Kinetics and Shelf-Life Extension of Lime Fruit (Citrus aurantifolium)

Coatings ◽

10.3390/coatings9050285 ◽

2019 ◽

Vol 9 (5) ◽

pp. 285 ◽

Cited By ~ 7

Author(s):

Neda Maftoonazad ◽

Hosahalli S. Ramaswamy

Keyword(s):

Weight Loss ◽

Ascorbic Acid ◽

Respiration Rate ◽

Storage Conditions ◽

Soluble Solids ◽

Coating Process ◽

Quality Loss ◽

Quality Change ◽

Order Model ◽

Kinetics Of

Uncertain storage conditions lead to considerable quality loss in lime fruits, which affect their consumer acceptability. Studies aimed at quantifying the kinetics of quality changes under different storage conditions are valuable for minimizing the product quality loss and improving their marketability. The objective of this study was to quantify the effect of pectin-based coating on the kinetics of quality change in stored limes fruits using a pre-established coating process. Lime fruits were immersed in the coating emulsion and then surface dried, cooled, and evaluated after storage for different times at selected temperatures (10–25 °C). Quality characteristics evaluated include physical (texture and color), chemical (ascorbic acid, pH, titrable acidity, total soluble solids), and physiological (respiration rate) properties. Results revealed that with the passage of time, the fruits showed progressive increase in shriveling or wilting and loss in green color, and higher temperatures accelerated these changes. The respiration rate in control samples reached 79, 35, and 7 mL CO2/(kg·h) after 7 days at 25 °C and 22 days at 15 and 10 °C, respectively, while those of coated samples were limited to 40, 32, and 1.06 mL CO2/(kg·h) after 11, 25, and 32 days at the same storage temperatures. Control fruits suffered 6%, 10%, and 24% weight loss following 8 days of storage at 10, 15, and 20 °C, respectively, while the losses in coated fruits were lower (2%, 4%, and 17%, respectively). A zero-order model was found appropriate for weight loss, along with a color a value and ΔE, while a first-order model was found to be better for firmness, brix to acidity ratio, ascorbic acid, and b and L values (R2 > 0.9). The Arrhenius model was suitable for temperature sensitivity of the rate constants.

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