CRYOPROTECTANTS PRESERVE QUALITY OF RESTRUCTURED TROUT PRODUCTS FOLLOWING FREEZE-THAW CYCLING

2005 ◽  
Vol 16 (4) ◽  
pp. 354-378 ◽  
Author(s):  
S. JITTINANDANA ◽  
P.B. KENNEY ◽  
S.D. SLIDER
Keyword(s):  
1977 ◽  
Vol 34 (12) ◽  
pp. 2369-2373 ◽  
Author(s):  
Doris Fraser Hiltz ◽  
D. H. North ◽  
Barbara Smith Lall ◽  
R. A. Keith

Refrozen silver hake (Merluccius bilinearis), processed as fillets and minced flesh after thawing of stored round fish that had been frozen within 14 h of capture, underwent rapid deterioration during storage at −18 °C compared with once-frozen control materials from the same lot of fish. The estimated maximum storage life of silver hake refrozen as fillets after 3 and 6 mo storage of the round fish at −25 °C was reduced to about 4.5 and 1 mo, respectively, from 10 mo for once-frozen control fillets. Quality of the refrozen materials immediately after thawing and refreezing was similar to that of the round-frozen fish, except after 6 mo, where some initial deterioration occurred, particularly in minced flesh. Minced flesh was more unstable in frozen storage than fillets. In all once- and twice-frozen materials, formation of dimethylamine occurred concomitantly with decrease in protein extractability. Round-frozen fish underwent no loss in protein extractability during 6 mo storage at −25 °C, but some lipid hydrolysis occurred. These results suggest that the freeze–thaw–refreeze process as applied to silver hake will yield a final product of acceptable quality provided that storage of the round fish does not exceed 3–4 mo and that the refrozen materials are marketed within a month after processing. Key words: silver hake, Merluccius bilinearis, refrozen storage, dimethylamine, minced flesh


2009 ◽  
Vol 58 (1) ◽  
pp. 70-85
Author(s):  
Henry Munack ◽  
Hilmar Schröder

Abstract. Ground temperature measurements have been carried out at eleven different sites of the Prokhodnaja valley in the high mountains of the Zailijskij Alatau (Northern Tian Shan, Kazakhstan) between the summers of 2003 and 2004. For this purpose the periglacial zone and adjacent altitudinal zones have been examined between 2,500 and 4,000 m asl with an equidistance of 250 m. The influences of the altitude, the exposure as well as the depth below the earth’s surface on the thermal content and condition of periglacial soils have been considered. The measurements provide useful information about the relations between quantity and quality of freeze-thaw action and the parameters mentioned above.


2020 ◽  
Vol 43 (11) ◽  
Author(s):  
Hongyao Jiang ◽  
Min Zhang ◽  
Yanan Sun ◽  
Bhesh Bhandari ◽  
Xi Wang

2020 ◽  
Vol 65 ◽  
pp. 102454 ◽  
Author(s):  
Jiaheng Li ◽  
Jiyong Shi ◽  
Xiaowei Huang ◽  
Xiaobo Zou ◽  
Zhihua Li ◽  
...  

1991 ◽  
Vol 18 (4) ◽  
pp. 681-689 ◽  
Author(s):  
C. James Martel ◽  
Carl J. Diener

In 1986, a pilot-scale sludge freezing bed was constructed at the U.S. Army Cold Regions Research and Engineering Laboratory in Hanover, New Hampshire, U.S.A. This bed was operated for the next three years using both anaerobically and aerobically digested sludges. Results indicate that both sludges were effectively dewatered by this process. The maximum depth of sludge frozen during this study was 1.14 m. The final solid contents were 39.3% and 24.5% for anaerobically digested and aerobically digested sludges respectively. The quality of the meltwater from the bed was similar to raw wastewater. The actual depth of sludge frozen and thawed in the bed during each year of operation was very close to that predicted by design models. Operational experience demonstrated the importance of a sand layer at the bottom of the bed for adequate drainage. Also, odors developed when the meltwater was allowed to accumulate in the bed. Odors were not a problem when the meltwater was drained away as quickly as it formed. Both sludges were easily removed with a front-end loader. Key words: sludge freezing bed, freeze–thaw conditioning, freeze–thaw separation, sludge dewatering, freezing bed.


2017 ◽  
Vol 15 (5) ◽  
pp. 475-483 ◽  
Author(s):  
Xiaoli Ji ◽  
Min Wang ◽  
Lingling Li ◽  
Fang Chen ◽  
Yanyang Zhang ◽  
...  

2018 ◽  
Vol 15 (4) ◽  
pp. 605-615
Author(s):  
Nguyen Thi Mong Diep ◽  
Elisabeth Blesbois

Semen cryopreservation allows crucial management of animal genetic diversity. However, the freeze-thaw process causes biochemical and physical alterations, impairing sperm energy-dependent functions. Currently, many chemicals are added to the media to enhance frozen-thawed sperm quality during artificial insemination. The aims of this study was to determine the effects of Metformin (Metf) on fresh chicken sperm motility and ability to perform acrosome reaction, and to evaluate Metf’s effects on the functions of cryopreserved sperm. Chicken semen was diluted and incubated at 35°C in media supplemented with or without different doses of 5’-AMP-Activated Protein Kinase (AMPK) activator, Metf (0,5 to 5 mM). We then looked for the concentration improving the most sperm quality to use it in the cryopreservation media used for chicken sperm. Our results show that 1 mM Metf is the concentration giving the best results regarding sperm quality. AMPKα phosphorylation, viability, acrosome reaction ability (AR), and various motility parameters, were negatively affected by the freeze-thaw process, and that Metf partially restored them. Sperm quality improved (mean increased by 23% for motility, by 10% for viability) as well as AMPKα phosphorylation (mean increased by 30%). Moreover, fluorescent intensity levels of phospho-AMPK were also stronger with Metf than in the control. These results show that the presence of Metf in fresh semen has a positive impact on the quality of sperm and helps reducing the gradual decline in sperm motility caused by cryopreservation by partially restoring several essential sperm functions, and thus leads to a better overall quality of cryopreserved sperm.


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>


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