scholarly journals Influence of the time/temperature binomial on the hydroxymethylfurfural content of floral honeys subjected to heat treatment

2012 ◽  
Vol 36 (2) ◽  
pp. 204-209 ◽  
Author(s):  
Roberta de Oliveira Resende Ribeiro ◽  
Carla da Silva Carneiro ◽  
Eliane Teixeira Mársico ◽  
Fernanda Lima Cunha ◽  
Carlos Adam Conte Junior ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Process Optimization ◽  
Storage Condition ◽  
Time Intervals ◽  
Maximum Value ◽  
Heat Treated ◽  
Different Temperatures ◽  
Processing And Storage ◽  
And Storage

Hydroxymethylfurfural (HMF) content is internationally recognized for its ability to indicate the freshness or lack of freshness of honey and can be used to judge the processing and storage condition of honey. The objective of the present study was to evaluate the evolution of HMF levels in fresh extracted honeys submitted to different temperatures ranging from 30 to 100º C, during pre-established time intervals (30, 45, 60, 180 and 720 minutes).The test was conducted in floral honey with an initial HMF content of 2.2 mg/Kg. The maximum value recommended by the Brazilian law (60 mg/Kg) was not exceeded in the samples subjected to heating for 30, 45 and 60 minutes regardless of the temperatures used. When the samples were heat treated during 180 minutes at 90º C the official value was surpassed. The highest values were observed in samples subjected to heating over 720 minutes, and the limit was exceeded at 70º C. The results obtained indicate that the HMF content gradually increases when the honey is heated at high temperatures for long periods. Therefore, we suggest a process optimization, considering the initial HMF content of the product and standardizing times and temperatures to ensure a good quality of the final product.

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 Processing and Storage on the Quality of Beetroot and Apple Mixed Juice

Foods ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1052
Author(s):  
Flavia Bianchi ◽  
Marina Pünsch ◽  
Elena Venir
Keyword(s):  
Antioxidant Activity ◽  
Shelf Life ◽  
Apple Juice ◽  
Beetroot Juice ◽  
Different Temperatures ◽  
Health Promoting ◽  
Shelf Life Studies ◽  
Processing And Storage ◽  
And Storage

In recent years, there has been a growing interest in the development of health-promoting and disease-preventing functional foods. Beetroot is a promising vegetable because of its outstanding antioxidant activity, vivid colour, and content of bioactive compounds. In the present study, the quality of pure beetroot and apple juices as well as that of their mixture was evaluated by measuring changes of colour, betalain content, and antioxidant activity during processing and storage. No perceivable colour changes of the beetroot juice were observed after adding apple juice up to 85% of the total amount. However, the antioxidant activity was proportionally reduced with the addition of apple juice. Pasteurization negatively affected the content of betalains but did not influence the antioxidant activity. Storage led to colour modifications and reduction of betalains and antioxidant activity. Through preliminary shelf-life studies, a durability of 65 days at room temperature for apple and beetroot juice blends was calculated. The novelty of this study lies in an extended description of physico-chemical characteristics of a fresh apple and beetroot blended juice obtained from local products, in the study of the effects of processing and storage on its quality, and in the estimation of its shelf-life after storage at different temperatures.

Heat Treatment Influence on the Corrosion Resistance of a Cu-Al-Fe-Mn Bronze

2018 ◽  
Vol 69 (5) ◽  
pp. 1055-1059 ◽  
Author(s):  
Mariana Ciurdas ◽  
Ioana Arina Gherghescu ◽  
Sorin Ciuca ◽  
Alina Daniela Necsulescu ◽  
Cosmin Cotrut ◽  
...  
Keyword(s):  
Heat Treatment ◽  
Corrosion Resistance ◽  
Structural Changes ◽  
Heating Temperature ◽  
Galvanic Corrosion ◽  
Cooling Water ◽  
Open Circuit ◽  
Water Quenching ◽  
Heat Treated ◽  
Different Temperatures

Aluminium bronzes are exhibiting good corrosion resistance in saline environments combined with high mechanical properties. Their corrosion resistance is obviously confered by the alloy chemical composition, but it can also be improved by heat treatment structural changes. In the present paper, five Cu-Al-Fe-Mn bronze samples were subjected to annealing heat treatments with furnace cooling, water quenching and water quenching followed by tempering at three different temperatures: 200, 400 and 550�C. The heating temperature on annealing and quenching was 900�C. The structure of the heat treated samples was studied by optical and scanning electron microscopy. Subsequently, the five samples were submitted to corrosion tests. The best resistance to galvanic corrosion was showed by the quenched sample, but it can be said that all samples are characterized by close values of open-circuit potentials and corrosion potentials. Concerning the susceptibility to other types of corrosion (selective leaching, pitting, crevice corrosion), the best corrosion resistant structure consists of a solid solution, g2 and k compounds, corresponding to the quenched and 550�C tempered sample.

scholarly journals Effect of Herbal Addition on the Microbiological, Oxidative Stability and Sensory Quality of Minced Poultry Meat

Foods ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 1537
Author(s):  
Danuta Jaworska ◽  
Elżbieta Rosiak ◽  
Eliza Kostyra ◽  
Katarzyna Jaszczyk ◽  
Monika Wroniszewska ◽  
...  
Keyword(s):  
Oxidative Stability ◽  
Sensory Quality ◽  
Meat Products ◽  
Black Pepper ◽  
Poultry Meat ◽  
Piper Nigrum ◽  
Thymus Vulgaris ◽  
Processing And Storage ◽  
And Storage

The study aimed to assess the effect of herbal additions with antioxidant properties (pepper, thyme and oregano) on the microbiological and oxidative stability as well as the sensory quality of minced poultry meat. Meatballs treatments without additives and treatments with the addition of three types of spices in two forms—dry spices and industrial extracts were examined. Popular seasoning additives of oregano (Origanum vulgare), thyme (Thymus vulgaris) and black pepper (Piper nigrum) at 0.3% of dry herbal or 0.003% as industrial extract were added to minced meat. The microbiological, chemical and sensory tests were performed at specified times and storage temperature. Based on the studied criteria, products maintained constant and adequate quality by up to 10 days while stored in 4 °C. In the case of all tested samples, the overall sensory quality began to deteriorate after 10 days of storage. The preservative role of herbs and extracts in meat products during processing and storage was observed. Oregano and black pepper in both forms maintained good microbial quality and showed their inhibitory effects on the growth of psychrotrophic bacteria. It was observed that dried herbs revealed a stronger antioxidant effect than additives in the form of extracts. The studied dried herbs played an antioxidant, antimicrobial and preservative role in meat products during processing and storage.

Calculating Salmonella Inactivation in Nonisothermal Heat Treatments from Isothermal Nonlinear Survival Curves

2001 ◽  
Vol 64 (5) ◽  
pp. 606-613 ◽  
Author(s):  
K. L. MATTICK ◽  
J. D. LEGAN ◽  
T. J. HUMPHREY ◽  
M. PELEG
Keyword(s):  
Differential Equation ◽  
Heat Treatment ◽  
Mathematical Models ◽  
Survival Curve ◽  
Survival Ratio ◽  
Survival Curves ◽  
Time Intervals ◽  
Heat Treated ◽  
Rich Media ◽  
Nonisothermal Conditions

Salmonella cells in two sugar-rich media were heat treated at various constant temperatures in the range of 55 to 80°C and their survival ratios determined at various time intervals. The resulting nonlinear semilogarithmic survival curves are described by the model log10S(t) = −b(T)tn(T), where S(t) is the momentary survival ratio N(t)/N0, and b(T) and n(T) are coefficients whose temperature dependence is described by two empirical mathematical models. When the temperature profile, T(t), of a nonisothermal heat treatment can also be expressed algebraically, b(T) and n(T) can be transformed into a function of time, i.e., b[T(t)] and n[T(t)]. If the momentary inactivation rate primarily depends on the momentary temperature and survival ratio, then the survival curve under nonisothermal conditions can be constructed by solving a differential equation, previously suggested by Peleg and Penchina, whose coefficients are expressions that contain the corresponding b[T(t)] and n[T(t)] terms. The applicability of the model and its underlying assumptions was tested with a series of eight experiments in which the Salmonella cells, in the same media, were heated at various rates to selected temperatures in the range of 65 to 80°C and then cooled. In all the experiments, there was an agreement between the predicted and observed survival curves. This suggests that, at least in the case of Salmonella in the tested media, survival during nonisothermal inactivation can be estimated without assuming any mortality kinetics.

scholarly journals Prestorage Heat Treatment as a Means of Improving Poststorage Quality of Apples

1990 ◽  
Vol 115 (2) ◽  
pp. 265-269 ◽  
Author(s):  
Joshua D. Klein ◽  
Susan Lurie
Keyword(s):  
Heat Treatment ◽  
Ethylene Production ◽  
Titratable Acidity ◽  
Soluble Solids ◽  
Optimum Temperature ◽  
Major Benefit ◽  
Solids Concentration ◽  
And Storage ◽  
Soluble Solids Concentration

The benefits conferred by a prestorage heat treatment on poststorage quality of apples (Malus domestics Borkh.) were measured on `Anna', a non-storing early cultivar, and `Granny Smith', a long-storing late cultivar. The major benefit was a decrease in rate of apple softening, both during OC storage and during simulated shelf life at 20C. Soluble solids concentration was not affected by heat treatment, but titratable acidity was reduced. Ethylene production after heat treatment and storage was similar to or higher than that of control apples, but respiration was lower. The optimum temperature and time combination for prestorage treatment of both cultivars was 4 days at 38C.

scholarly journals Influence of different method and different storage life on moisture and senzorial evaluation of durable salamis

2008 ◽  
Vol 56 (4) ◽  
pp. 183-196
Author(s):  
Hana Šulcerová ◽  
Jiří Štencl ◽  
A. Šulcová
Keyword(s):  
Storage Time ◽  
Storage Temperature ◽  
Heat Treated ◽  
Different Temperatures ◽  
The Difference ◽  
Total Difference ◽  
Cut Surface ◽  
Sausage Casing ◽  
General Appearance

Heat-treated salamis “Vysočina“ were produced with standard way in a meat factory; their diameter was 55 mm. Samples were stored under laboratory conditions at different temperatures: 5, 10, 15, 20, and 25 °C and sensory analysed every week during one month storage. The dry matter (d.m.) was measured, too. Descriptors of general appearance, sausage casing, texture, cut surface, dry edge, smell, taste, and salty were monitored. Biggest changes were in descriptors general appearance and sausage casing (P < 0.001) and also in dry edge (P < 0.010) during the month period. Germs of moulds were found only at 5 and 10 °C. Rapid increase of d.m. in samples was noticeable in the first week of the storage time. It was 3 % d.m. at 5 °C and 11 % d.m. at 25 °C. Increase of d.m. of salamis continues slowly in the next three weeks period; the total difference was about 10 % d.m. in the temperature range measured. Decrease of d.m. at 5 °C was noticed in the last week of the measurement. The difference was 3.5 % d.m. This change means that the equilibrium moisture content of the samples of salamis has been reached at the temperature 5 °C. The best sensorial quality of salamis “Vysočina” was in the storage temperature ranged from 15 to 20 °C.

scholarly journals A Hyperconnected Smart City Framework

2020 ◽  
Vol 24 ◽  
Author(s):  
Naureen Naqvi ◽  
Sabih Ur Rehman ◽  
Zahidul Islam
Keyword(s):  
Smart City ◽  
Smart Cities ◽  
Security And Privacy ◽  
Directed Network ◽  
Web Based ◽  
Sustainable Environment ◽  
Processing And Storage ◽  
The Impact ◽  
And Storage

Recent technological advancements have given rise to the concept of hyper-connected smart cities being adopted around the world. These cities aspire to achieve better outcomes for citizens by improving the quality of service delivery, information sharing, and creating a sustainable environment. A smart city comprises of a network of interconnected devices also known as IoT (Internet of Things), which captures data and transmits it to a platform for analysis. This data covers a variety of information produced in large volumes also known as Big Data. From data capture to processing and storage, there are several stages where a breach in security and privacy could result in catastrophic impacts. Presently there is a gap in the centralization of knowledge to implement smart city services with a secure architecture. To bridge this gap, we present a framework that highlights challenges within the smart city applications and synthesizes the techniques feasible to solve them. Additionally, we analyze the impact of a potential breach on smart city applications and state-of-the-art architectures available. Furthermore, we identify the stakeholders who may have an interest in learning about the relationships between the significant aspects of a smart city. We demonstrate these relationships through force-directed network diagrams. They will help raise the awareness amongst the stakeholders for planning the development of a smart city. To complement our framework, we designed web-based interactive resources that are available from http://ausdigitech.com/smartcity/.

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