Effect of Freezing Rate and Starch Granular Morphology on Ice Formation and Non-Freezable Water Content of Flour and Starch Gels

The meat freezing, as a method of preservation, aims to maximize the storage period with preserving the quality and nutritional value of the product. However, freezing causes certain changes in the foodstuff. These changes are the result of ice formation and lead to a change in meat quality after thawing. The aim of this paper was to examine the effect of freezing rates on the physicochemical properties of pork meat (M. Longissimus dorsi). The meat samples were frozen at 10 different rates and after 24 hours of storage at -18?C, thawed at +4?C. Samples frozen at the lowest freezing rate (0.23 cm/h) had the lowest water content (72.02%), while for the samples frozen at the highest rate (1.43 cm/h), significantly higher (p<0.05) water content was recorded (73.85%). The protein content ranged from 23.34% (rate 0.50 cm/h) to 23.76% (rate 1.43 cm/h). The increase in freezing rates from 0.23 cm/h to 1.43 cm/h statistically significantly (p<0.05) affected the increase in the pH value (from 5.41 to 5.72). By measuring water holding capacity (WHC) the least amounts of released liquid (2.27 cm2 and 2.23 cm2) were recorded at higher freezing rate (1.00 cm/h and 1.43 cm/h, respectively). The highest thawing loss was determined in pork samples frozen at slower rate (0.23 cm/h) (3.61%).

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Impacts of air drying and DIC pretreatments on textural properties of frozen/thawed apple fruits

Proceedings of 21th International Drying Symposium ◽

10.4995/ids2018.2018.8371 ◽

2018 ◽

Author(s):

Sihem Bellaga ◽

L. Ben Haj Said ◽

K. Allaf

Keyword(s):

Water Content ◽

Research Work ◽

Textural Properties ◽

Freezing Rate ◽

Air Drying ◽

Sample Water ◽

Instant Controlled Pressure Drop ◽

The Impact ◽

Drop Water ◽

Apple Fruits

This research work is about dehydrofreezing assisted by DIC treatment as an innovative conservation process of apple fruits. Samples previously dehydrated and DIC treated were frozen at -30 °C and at two different practical freezing rates. The effects of sample water content (W) and practical freezing rate (PFR) on freezing characteristics and apple texture were examined. Thaw exudate water (TEW) of 200% and 100% db samples was approximately 3 g/100 g water. Whereas, it was lower than 0.5 g/100 g water for samples with 30% db W during thawing at 4 °C. Moreover, the impact of PFR on TEW was significant and very important only for high W samples. For samples whose water content was lower than 100% db, firmness was as higher as the W was lower, without any significant impact of PFR. Keywords: Dehydrofreezing; Instant controlled pressure drop; Water content; Practical freezing rate; Texture.

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Water content, hydraulic conductivity, and ice formation in winter stems of Pinus contorta: a TDR case study

Oecologia ◽

10.1007/s004420000587 ◽

2001 ◽

Vol 127 (4) ◽

pp. 468-475 ◽

Cited By ~ 68

Author(s):

Jed P. Sparks ◽

Gaylon S. Campbell ◽

Alan R. Black

Keyword(s):

Hydraulic Conductivity ◽

Water Content ◽

Pinus Contorta ◽

Ice Formation

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FREEZABLE WATER CONTENT AND THE OXYGEN RESPIRATION IN WHEAT AND RYE GRAIN AT DIFFERENT STAGES OF RIPENING

American Journal of Botany ◽

10.1002/j.1537-2197.1942.tb13977.x ◽

1942 ◽

Vol 29 (2) ◽

pp. 105-109 ◽

Cited By ~ 3

Author(s):

Harold G. Shirk

Keyword(s):

Water Content ◽

Freezable Water

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Non-Destructive Prediction of Moisture Content and Freezable Water Content of Purple-Fleshed Sweet Potato Slices during Drying Process Using Hyperspectral Imaging Technique

Food Analytical Methods ◽

10.1007/s12161-016-0722-0 ◽

2016 ◽

Vol 10 (5) ◽

pp. 1535-1546 ◽

Cited By ~ 27

Author(s):

Yue Sun ◽

Yunhong Liu ◽

Huichun Yu ◽

Anguo Xie ◽

Xin Li ◽

...

Keyword(s):

Moisture Content ◽

Water Content ◽

Sweet Potato ◽

Hyperspectral Imaging ◽

Imaging Technique ◽

Drying Process ◽

Freezable Water ◽

Non Destructive ◽

Potato Slices

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A Study of Intracellular Ice Formation in Jurkat Cells

ASME 2008 Summer Bioengineering Conference, Parts A and B ◽

10.1115/sbc2008-192334 ◽

2008 ◽

Author(s):

Tathagata Acharya ◽

Ram V. Devireddy

Keyword(s):

Cooling Rate ◽

Jurkat Cells ◽

Freezing Rate ◽

Ice Formation ◽

Substantial Evidence ◽

Cooling Rates ◽

Cryoprotective Agents ◽

Intracellular Ice Formation ◽

Intracellular Ice ◽

Phosphate Buffered Saline

The objective of this study was to characterize the IIF behavior of Jurkat cells in isotonic conditions in the absence of any cryoprotective agents. The Jurkat cells were collected from culture and then washed and re-suspended in Dulbecco’s Phosphate Buffered Saline (PBS). The freezing experiments were carried out at defined freezing protocols and at various freezing rates of 5, 20, 30 and 50 °C/min. The results suggest there was no substantial evidence of intracellular ice formation at lower cooling rates of 5, 20 and 30° C/min. The first conspicuous indication of intracellular ice formation (IIF) was observed at a freezing rate of 50 °C/min. At this cooling rate, unlike the usual sudden blackening of cells, the cells suddenly grew and exploded suggesting the formation of intracellular ice, which was reminiscent of a prior observed phenomenon for IIF.

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Analysis of freezable water content by DSC for apple dormant bud cryopreservation

Horticultural Science ◽

10.17221/146/2018-hortsci ◽

2019 ◽

Vol 46 (No. 4) ◽

pp. 163-170

Author(s):

Alois Bilavčík ◽

Jiří Zámečník ◽

Miloš Faltus ◽

Petra Jadrná

Keyword(s):

Water Content ◽

Apple Tree ◽

Winter Season ◽

Regeneration Rate ◽

Central European ◽

Freezable Water ◽

Temperate Trees ◽

Step Procedure ◽

Dormant Bud ◽

High Regeneration

Dormant bud cryopreservation is a valuable tool for the germplasm of temperate trees preservation. Freezable water content, as an important cryopreservation characteristic, was analysed by DSC. Scions of modern apple tree varieties (Malus domestica) were collected during the winter season from orchards, freeze-dehydrated to 26–32% of water content at –5°C and cryopreserved by the two-step procedure. Samples were rehydrated in moist peat after 4 months of cryopreservation and grafted on rootstocks in a field. Regeneration by sprouting buds on rootstocks was evaluated. The varieties were divided into three groups according to their water content and percentage of crystallized water. The regeneration in the three groups decreased with decreasing bud water content. Regeneration was higher than 80% in most of the varieties and reached 100% in almost 1/3 of the tested varieties. In only one variety, was regeneration lower than 40%, which is still a high regeneration rate for considering apple genotypes as successfully cryopreserved. According to this study, the two-step cryoprotocol was successfully optimized for Central European conditions.

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