Seasonal Changes in Quality of Chonggak Kimchi Fermented at Different Temperatures

The presence of yeasts in milk may cause physical and chemical changes limiting the durability and compromising the quality of the product. Moreover, milk and dairy products contaminated by yeasts may be a potential means of transmission of these microorganisms to man and animals causing several kinds of infections. This study aimed to determine whether different species of yeasts isolated from bovine raw milk had the ability to develop at 37°C and/or under refrigeration temperature. Proteinase and phospholipase activities resulting from these yeasts were also monitored at different temperatures. Five genera of yeasts (Aureobasidium sp., Candida spp., Geotrichum spp., Trichosporon spp. and Rhodotorula spp.) isolated from bovine raw milk samples were evaluated. All strains showed one or a combination of characteristics: growth at 37°C (99·09% of the strains), psychrotrophic behaviour (50·9%), proteinase production (16·81% of the strains at 37°C and 4·09% under refrigeration) and phospholipase production (36·36% of the isolates at 37°C and 10·9% under refrigeration), and all these factors may compromise the quality of the product. Proteinase production was similar for strains incubated at 37°C (16·81% of the isolates) and room temperature (17·27%) but there was less amount of phospholipase-producing strains at room temperature (15·45% of the isolates were positive) when compared with incubation at 37°C (36·36%). Enzymes production at 37°C by yeasts isolated from milk confirmed their pathogenic potential. The refrigeration temperature was found to be most efficient to inhibit enzymes production and consequently ensure better quality of milk. The viability of yeasts and the activity of their enzymes at different temperatures are worrying because this can compromise the quality of dairy products at all stages of production and/or storage, and represent a risk to the consumer.

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A Comparative Study of Soldering Temperatures and Materials on the Reliability of Photovoltaic Modules

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.562-564.188 ◽

2012 ◽

Vol 562-564 ◽

pp. 188-191

Author(s):

Keh Moh Lin ◽

Yang Hsien Lee ◽

Wen Yeong Huang ◽

Po Chun Hsu ◽

Chin Yang Huang ◽

...

Keyword(s):

Comparative Study ◽

Lead Free ◽

Automatic Process ◽

Lead Free Solder ◽

Snagcu Solder ◽

Photovoltaic Modules ◽

Soldering Process ◽

Different Temperatures ◽

Free Solder

To find out the important factors which decisively affect the soldering quality of photovoltaic modules, solar cells were soldered under different conditions (different temperatures, PbSn vs. SnAgCu solder, manual vs. semi-automatic). Experimental results show that the soldering quality of PbSn under 350°C in the semi-automatic soldering process was quite stable while the soldering quality of lead-free solder was generally unacceptable in the manual or semi-automatic process under different temperatures. This result indicates that the soldering process with lead-free solder still needs to be further improved. It was also found that most cracks were formed on the interface between the solder and the silver paste and then expanded outwards.

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Effect of Humidity-Controlled Dehydration on Microbial Growth and Quality Characteristics of Fresh Wet Noodles

Foods ◽

10.3390/foods10040844 ◽

2021 ◽

Vol 10 (4) ◽

pp. 844

Author(s):

Jun-Jie Xing ◽

Dong-Hui Jiang ◽

Zhen Yang ◽

Xiao-Na Guo ◽

Ke-Xue Zhu

Keyword(s):

Shelf Life ◽

Microbial Growth ◽

Treatment Time ◽

Positive Influence ◽

Quality Characteristics ◽

Plate Count ◽

Cooking Properties ◽

Total Plate Count ◽

Different Temperatures

Humidity-controlled dehydration (HCD) was innovatively applied in this paper to control the growth of microorganisms in fresh wet noodles (FWN). Effects of HCD treatment with different temperatures (40, 60 or 80 °C), relative humidity (RH, 50%, 70% or 90%) and treatment time (5–32 min) on the total plate count (TPC), the shelf-life, and qualities of FWN were investigated. The results showed that HCD reduced the initial microbial load on the fresh noodles and extended the shelf-life up to 14–15 days under refrigeration temperature (10 °C). A 1.39 log10 CFU/g reduction for the initial TPC was achieved after HCD treatment at the temperature of 60 °C and RH of 90%. HCD with higher RH had a more positive influence on quality improvement. The L* values, the apparent stickiness, and the cooking properties of the noodle body were improved by HCD while good sensory and texture quality of noodles were still maintained after the dehydration process.

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ELECTRICAL CONDUCTIVITY AND QUALITY OF DIFFERENT UMBEL ORDER CARROT SEEDS

Revista Brasileira de Agropecuária Sustentável ◽

10.21206/rbas.v9i04.8079 ◽

2020 ◽

Vol 9 (04) ◽

pp. 75-81

Author(s):

Luana de Souza Marinke ◽

Hugo César Rodrigues Moreira Catão ◽

Gabrielly Fernanda Francisco ◽

Ítala Menegon Castilho ◽

Letícia Rodrigues de Oliveira ◽

...

Keyword(s):

Electrical Conductivity ◽

Germination Rate ◽

Statistical Design ◽

Germination Test ◽

Aerial Portion ◽

Initial Characterization ◽

Different Temperatures ◽

Physiological Quality ◽

Final Score

Carrot seeds exhibit irregular vigor due to the wide blooming period of the crop. Results from germination tests are insufficient to evaluate the physiological potential. Thus, vigor tests are used in combination with germination tests. The objective of this work was to evaluate the quality of carrot seeds from different umbel order and the electrical conductivity under different temperatures and imbibing periods. Carrot seeds from cultivar Brasilia were used to perform the experiments. Content of water, the first and the final score of the germination test, index of germination rate, and length of roots and of the aerial portion were determined in the initial characterization. The electrical conductivity test was completed with replicates containing 50 seeds, in 25 mL deionized water at 20, 25 and 30oC. Evaluations were performed with 2, 4, 6, 8, 12 and 24 hours of imbibing period. The experiment was accomplished under a completely random statistical design. The quality of carrot seeds varied according to the umbel order. Seeds of secondary umbels showed better physiological quality. The electrical conductivity test is efficient to evaluate the vigor of carrot seeds with 8 hours of imbibing period at 25°C.

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Assessment Mixing and Compaction Temperatures for Modified HMA Using Superpave High Shear Viscosity Methods

Al-Nahrain Journal for Engineering Sciences ◽

10.29194/njes.21040516 ◽

2018 ◽

Vol 21 (4) ◽

pp. 516-522 ◽

Cited By ~ 3

Author(s):

Alaa Hussein Abed ◽

Ali Hwaidi Nasser

Keyword(s):

Shear Viscosity ◽

Asphalt Mixture ◽

High Shear ◽

Compaction Temperature ◽

Modified Asphalt ◽

Performance Grade ◽

Modified Binders ◽

Different Temperatures ◽

Marshall Stability

The objective of this study is determining the mixing and compaction temperature of the modified asphalt mixture. Results of binder tests showed that the addition of 3% SBS to control asphalt (PG 64-16) would achieve the desired performance level (PG 76-16) a performance grade that fits our climate with traffic loads. When using 5% SBS the performance grade of binder increased three grades (PG 82-16) and when increasing SBS content to 8% the performance grade increased four grades (PG 88-16). At shear rate of 500 (s-1), the modified asphalt viscosity can be obtained at different temperatures and the viscosity temperature curve can be achieved. As a result, the mixing and compaction temperature of modified asphalt can be determined to reach 0.17 ± 0.02 Pa.s and 0.28 ± 0.03 Pa.s for mixing and compaction, respectively. It is noted that SBS modified reached a viscosity of 3 Pa.s when 8 % additive. Additive contents above these values may not be suitable for good workability and pump ability according to Superpave specifications. While addition of 5% SBS with control asphalt, more than 3.7times at 135°C Increase the viscosity. Marshall Stability test indicated that the strength for the SBS specimens increases as compared to the conventional specimens. An increase of about 39%, 74%, 102%, was observed with 3%SBS 5%SBS 8%SBS modified binders, respectively. The Marshall test results for 8%SBS binders required compaction temperatures above 175°C need to keep up quality of HMA item while limiting natural effect amid development, these proposals are unsatisfactory Modified mixtures the 5% SBS modification was determined to be the maximum useful content. The Superpave method to estimate mixing and compaction temperatures show are not practical for use with modified binders. Also, it is observed that good agreement values between the average Marshall compaction temperature and the High Shear Viscosity Method (HSRV) and lower than Superpave methods Where the decline ranges from 15 ºC to 17 ºC.

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Quality and shelf life of packaged fresh sliced mushrooms stored at two different temperatures

Agricultural and Food Science ◽

10.2137/145960606780061461 ◽

2008 ◽

Vol 15 (4) ◽

pp. 414 ◽

Cited By ~ 8

Author(s):

E. GONZÁLEZ-FANDOS ◽

A. SIMON JIMENES ◽

V. TOBAR PARDO

Keyword(s):

Carbon Dioxide ◽

Shelf Life ◽

Agaricus Bisporus ◽

Microbiological Quality ◽

Air Atmosphere ◽

Pvc Film ◽

Different Temperatures ◽

Aerobic And Anaerobic ◽

Quality And Shelf Life

The sensory and microbiological quality of sliced mushrooms (Agaricus bisporus L.) packaged in films of perforated and non-perforated PVC and stored at 3 and 9ºC, was studied. The carbon dioxide and oxygen content inside the packages, colour, weight loss, sensory attributes, mesophiles, Pseudomonas, Enterobacteriaceae, aerobic and anaerobic spore formers were determined. The atmosphere generated with the perforated PVC film was similar to that of air atmosphere at 3 or 9ºC. T.he non-perforated PVC film generated inside the packages CO2 : O2 concentrations of 3.4% : 8.1% at 3ºC and CO2 : O2 concentrations of 4.5% : 0.15% at 9ºC. Browning of mushrooms was lower at 3 than at 9ºC. The quality of sliced mushrooms packaged in perforated PVC and stored at 3ºC was adequate after 9 days. However, at 9ºC, the slice deformation and brown blotches incidence were severe after 9 days. The atmosphere generated with non-perforated PVC inhibited aerobic microorganism growth compared to mushrooms packaged in perforated PVC. At 3ºC, the shelf life of mushrooms packaged in non perforated PVC was around 13 days. However, the extremely low O2 atmospheres generated at 9ºC was accompanied by off-odours and growth of anaerobic spore formers, although the appearance of sliced mushrooms was acceptable.;

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

Acta Universitatis Agriculturae et Silviculturae Mendelianae Brunensis ◽

10.11118/actaun200856040183 ◽

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.

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Quality of fresh-cut avocado (Persea americana Mill.) stored under different temperatures

Ciência e Agrotecnologia ◽

10.1590/s1413-70542009000400021 ◽

2009 ◽

Vol 33 (4) ◽

pp. 1095-1102 ◽

Cited By ~ 5

Author(s):

Ana Carla Marques Pinheiro ◽

Eduardo Valério de Barros Vilas Boas ◽

Lucas Carvalho e Silva ◽

Alessandra de Paiva Alves ◽

Marcelo La Selva ◽

...

Keyword(s):

Persea Americana ◽

Sodium Hypochlorite Solution ◽

Rigid Plastic ◽

Randomized Design ◽

Pvc Film ◽

Different Temperatures ◽

Fresh Cut ◽

Hedonic Scale ◽

Storage Temperatures

The goal of this work was to evaluate the effect of different storage temperatures on the quality maintenance of fresh-cut 'Fortuna' avocado (Persea americana Mill.). The fruit was selected, washed and sanitized with sodium hypochlorite solution (190 ppm total residual chlorinee) for 15 minutes. After that, the tip was cut and the fruit was also cut in halves, peeled and the pit removed, manually. Then the halves were immersed in 0.5% calcium chlorite + 0.5% cysteine solution for 2 minutes, to avoid darkening and packed in rigid plastic covered with 20 micrometer thick plastic wrap (PVC film) with a permeability to O2, CO2 and water vapor of 15,000, 80,000 and 390 cm³/m²/day, respectively. The product was stored under 3 different temperatures 0, 5, 10ºC and evaluated at 5 different storege periods of 0, 2, 3, 5 and 6 days, in a randomized design in a 3x5 factorial. The storage of fresh-cut avocado at 5ºC is the best alternative because it determines better maintenance of quality of the avocado. These presented lower darkening of pulp, better scores for appearance and acceptability, lower softening and polyphenoloxidase activity, in comparison to those stored at 0 and 10ºC. The fresh-cut avocados stored at 5ºC presented a shelf life of 5 days, based, mainly on, appearance, score 7.3, sited between the concepts "like moderately" and "like very much" on a hedonic scale of 9 points and 86% of acceptability, at the end of 5 days of storage.

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Test Gas Generation from Pure Liquids: An Application-Oriented Overview of Methods in a Nutshell

International Journal of Chemical Engineering ◽

10.1155/2012/417029 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6 ◽

Cited By ~ 15

Author(s):

Yue Li ◽

Tim Täffner ◽

Michael Bischoff ◽

Bernd Niemeyer

Keyword(s):

Organic Compounds ◽

Field Experiments ◽

Gas Generation ◽

Flow Rates ◽

Test Gas ◽

Advantages And Disadvantages ◽

Volatile Organic ◽

Different Temperatures ◽

Accuracy And Stability

The generation of test gas from pure liquids has a wide variety of applications in laboratory and field experiments, for which the quality of the test gas is of significance. Therefore, various methods for test gas generation have been designed. Each method has unique advantages and disadvantages. Thus, a short overview is presented within the scope of this paper. Furthermore, a common bubbler system is presented, which was built to generate test gas from volatile organic compounds for experimental usage in laboratory applications. An analysis is conducted with respect to the generated concentrations at different temperatures and flow rates of the diluting gas. Accuracy and stability of this method are investigated.

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Study on Changes of Textural and Biochemical Properties of Tuna during Ultra-Low Temperature Storage

Environment and Natural Resources Research ◽

10.5539/enrr.v6n2p51 ◽

2016 ◽

Vol 6 (2) ◽

pp. 51 ◽

Cited By ~ 1

Author(s):

Yu-ying PAN ◽

Xiao-hua QIU ◽

Jin-sheng YANG

Keyword(s):

Soluble Protein ◽

Storage Time ◽

Storage Temperature ◽

Frozen Storage ◽

Biochemical Properties ◽

Texture Profile ◽

Low Temperature Storage ◽

Different Temperatures ◽

Temperature Storage

The effect of TPA and biochemical properties of Yellow Tuna during frozen storage at different temperatures(-18°C, -25°C, -35°C, -45°C, -55°C, -65°C) were studied by measuring the textural characteristics (the hardness, Springiness) salt-solubility of myofibrillar proteins, Ca2+ATPase activities. The results indicated that the hardness, springiness, actomyosin salt-solubility, Ca2+ATPase activities decreased during the process of frozen storage. Meanwhile, the frozen stored temperature showed great effect on the freezing denaturation of protein (P < 0.05). For the same longer of the storage time, the lower frozen temperature, the less extent of freeze denaturation; Stored in -18°C for three months, the content of Salt soluble protein reduced to zero; Stored in -25°C for 120 days, the content of salt soluble protein also reduced to zero; But stored in -55°C and -65°C, the change is very little. Ca2+ATPase activities also reduced to zero after stored in -18°C and -25°C for three months. But stored in -55°C and -65°C, there is no obvious change. Moreover, there is a Positive relationship between the change of texture profile and the content of Salt soluble protein, the lower the storage temperature, the less of the change of texture profile. Therefore, when it is stored in -55°C, the quality of Yellow Tuna can be maintained to the maximum extent within six months.

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