Meat Freezing

Cooldown of Products after Cooking

eben van tonder history of food, Meat Freezing, sausage chilling , , , , 
Cooldown of Products after Cooking
Eben van Tonder
17 February 2022

Introduction

I am part of a team designing a meat processing factory in Lagos, Nigeria. I considered refrigeration from the standpoint of the effect of long term storage on product quality. In 2018 I did a comprehensive survey of The Freezing and Storage of Meat. I looked at weight loss during chilling and storage of meat. In 2019 I looked at Weight Loss During Chilling and Freezing of Meat. This time, the issue at hand is rapid cooling after cooking. Home Production of Quality Meats and Sausages by John Novak provided great introductory comments and he was kind enough to mail me the relevant chapter of his book.

He summarises the important point as follows: “Cooling down of cooked products is basically done to cross the danger zone (140o – 40oF; 60oC – 4oC) relatively fast. Cooked sausage at 160oF (72oC) so is still basically safe until the temperature drops down to about 60oC. Therefore, the restaurants are required to hold hot food at 140o F (60oC) or higher.” (Novak)

Regulatory Standard and Application

“The following standards come from the Food Safety and Inspection Service (FSIS), United States Department of Agriculture (USDA):

Compliance Guidelines for Cooling Heat-Treated Meat and Poultry Products (Stabilization)

It is very important that cooling be continuous through the given time/temperature control points. Excessive dwell time in the range of 130°F (55oC) to 80°F (27oC) is especially hazardous, as this is the range of most rapid growth for the clostridia. Therefore cooling between these temperature control points should be as rapid as possible.

1. During cooling, the product’s maximum internal temperature should not remain between 130°F (55oC) and 80°F (27oC) for more than 1.5 hours nor between 80°F (27oC) and 40°F (4oC) for more than 5 hours. This cooling rate can be applied universally to cooked products (e.g., partially cooked or fully cooked, intact or non-intact, meat or poultry) and is preferable to (2) below.

2. Over the past several years, FSIS has allowed products to be cooled according to the following procedures, which are based upon older, less precise data: chilling should begin within 90 minutes after the cooking cycle is completed. All products should be chilled from 120°F (48°C) to 55°F (12.7°C) in no more than 6 hours. Chilling should then continue until the product reaches 40°F (4.4°C); the product should not be shipped until it reaches 40°F (4.4°C). This second cooling guideline is taken from the former (“Requirements for the production of cooked beef, roast beef, and cooked corned beef”, 9 CFR 318.17(h)(10). It yields a significantly smaller margin of safety than the first cooling guideline above, especially if the product cooled is a non-intact product.

If an establishment uses this older cooling guideline, it should ensure that cooling is as rapid as possible, especially between 120°F (48°C) and 80°F (27oC), and monitor the cooling closely to prevent deviation. If product remains between 120°F (48°C) and 80°F (27oC) for more than one hour, compliance with the performance standard is less certain.

3. The following process may be used for the slow cooling of ready-to-eat meat and poultry cured with nitrite. Products cured with a minimum of 100 ppm ingoing sodium nitrite may be cooled so that the maximum internal temperature is reduced from 130 to 80° F in 5 hours and from 80 to 45° F in 10 hours (15 hours total cooling time).

This cooling process provides a narrow margin of safety. If a cooling deviation occurs, an establishment should assume that their process has exceeded the performance standard for controlling the growth of Clostridium perfringens and take corrective action. The presence of the nitrite, however, should ensure compliance with the performance standard for Clostridium botulinum.

From FSIS Directive 7117.0

1. Heat-resistant food-poisoning bacteria can grow from 38°F 3oC up to approximately 125°F (49oF); however their range of rapid growth is from approximately 80°F to 125° F. Thus, cooling product quickly through the rapid growth range is more important than cooling through the slow growth range.

2. The rate of heat transfer (cooling rate) from the product’s centre to its surface is directly proportional to the difference in temperature between those two points. Thus, as the product temperature approaches the coolant temperature, the cooling rate diminishes.

3. Traditional cured products, containing high amounts of salt and nitrite, together with low moisture content are more resistant to bacterial growth than similar newer products; some are even shelf-stable. Thus, rapid cooling of these traditional products is not always necessary. However, manufacturers are making fewer products of this type today. Instead, to meet present consumer tastes, most of their cured products contain less salt and more moisture. These changes minimize the inhibitory effect of added nitrite and increase the need to rapidly cool these products.” (Novak)

Water Cooling

The best way to cool sausages down is with water. Showering with cold water is a technique universally used. “Water removes heat much faster than air and hot products will drop their temperature fast. If a product was smoked such showering also cleans the surface of any remaining smoke particles and prevents shrivelling.” (Novak)

Let’s delve deeper into the science behind cooling. To do this we use Watts per meter-Kelvin (W/mK) or what is known as the ‘k Value’. It is the measure used to compare thermal conductivity. The k value, or Thermal Conductivity, is the rate of heat transfer in a homogeneous material. A k value of 1 means that 1m cube of a material will transfer heat at a rate of 1 watt for every degree of temperature difference between opposite faces. This will be given as 1 W/mK. The lower this value is, the less heat the material will transfer.

Chris and Steve James point out that “the thermal conductivity of processed meat products (including cured sausages and hams) range between 0.272 Wm-1K-1 at 22°C to 0.482 Wm-1K-1 at 80°C (Marcotte et al., 2008), whereas the thermal conductivity of water is 1 Wm-1K-1. Thus, the thermal conductivity of water is more than double that of most processed meats.”  Water sprayed onto the surface of a food product will act as a high conductivity path. 

Intermitted Spray Cooling

Chris and Steve James made their comments on a blog site related to intermitted spray cooling in response to someone claiming that water on the surface of a product acts as an insulator which is obviously incorrect not the case, as one can see when comparing the K value of the sausages and that of water. They stated that “the reason why intermittent spray cooling can have benefits over continuous spray cooling is that a break in spraying allows the water on the surface of the hot product to evaporate, thus enhancing the cooling effect.”

Panão (2008) investigated the physics involved in the heat transfer process using intermitted spray cooling. Their work has shown that small duty cycles promote heat removal by phase-change. They found that “as the duty cycle evolves toward the continuous spray condition, the cooling system’s thermal response improves, but phase-change is mitigated, affecting the system’s performance. Intermittent spray cooling is also compared with continuous spray cooling experiments and liquid savings has been estimated by 10–90% for the same energetic efficiencies reported in the literature.” They further recommend using shorter impingement distances and low injection pressures. (Panão, 2008)

Craig Habbick who has experience with these systems recommends the following procedure. Brine solution (water and salt) cooled to -5oC and sprayed intermittently altering 2 minutes to 1 minute off with circulation on during the spray off times. The entire cycle takes 15 minutes and reduces core temperature from 72oC to 2oC.

The concentration of salt was high. They used a Baume meter regulator to test the salt. Weight loss was so low that they had to remove water from the recipe due to seepage in the packs after packaging. Nett loss during cool down was around 2%. They used an Alkar brine chiller.

For details on the Alkar Brine Chiller, visit https://alkar.com/liquid-brine-chiller/

The important graphs from the Alkar website are:

Pre-cooling

Novac remarks that there is no need to grab a water hose the moment the sausage was cooked in a smokehouse to 155° F (69°C) as this temperature lies outside the danger zone (40 – 140°F, 4 – 60°C). “U.S. regulations permit restaurants to hold cooked food at 145°F (63°C) or higher temperatures. However, once when the temperature of the product drops to 140°F (60°C), it should be cooled fast. The surface of a product such as a head cheese or smoked sausage both will benefit from a brief hot shower or immersing them in hot water. This will remove any possible grease from the outside and the product will look better. Then it will be showered with cold water. Some pork products may be cooked to > 137° F (58°C) just to eliminate the danger of contracting Trichinae. Such products should be cold showered immediately as they are already lying within the danger zone.” (3. Traditional cured products, containing high amounts of salt and nitrite, together with low moisture content are more resistant to bacterial growth than similar newer products; some are even shelf-stable. Thus, rapid cooling of these traditional products is not always necessary. However, manufacturers are making fewer products of this type today. Instead, to meet present consumer tastes, most of their cured products contain less salt and more moisture. These changes minimize the inhibitory effect of added nitrite and increase the need to rapidly cool these products.” (Novak)

Blast Chiller

We initially planned to have a blast chiller, but after the recommendation from Craig Habbick, the intermitted spray cooling system is so effective that there is no need for an air chiller (blast chiller).

Further Reading

Thermophysical-properties-of-processed-meat-and-poultry-productsDownload
Intermittent_spray_cooling_a_new_technolDownload

The Alkar product Brochure

ALKAR_Brine_ChillerDownload

References

Jensen, W. K., Devine, C., Dikeman, M. (Editors), (2014), Encyclopedia of Meat Sciences, Second Edition. ISBN: 9780123847317. Elsevier.

Marcotte, M., Taherian, A. R. & Karimi, Y. (2008) Thermophysical properties of processed meat and poultry products.  Journal of Food Engineering. Vol. 88:3, pp315-322

Miguel R.O. Panão, António L.N. Moreira, Intermittent spray cooling: A new technology for controlling surface temperature, International Journal of Heat and Fluid Flow, Volume 30, Issue 1, 2009, Pages 117-130, ISSN 0142-727X, https://doi.org/10.1016/j.ijheatfluidflow.2008.10.005.

Novak, J. Home Production of Quality Meats and Sausages

Photo Reference

https://www.123rf.com/stock-photo/sausage_chains.html?sti=mkg0hin5vkbrg05qx4|

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Weight Loss During Chilling and Freezing of Meat

eben van tonder history of food, Meat Freezing , ,

Weight Loss During Chilling and Freezing of Meat
By:  Eben van Tonder
10 March 2019

chiller-in-meat-plant-500x500

FREEZING AND STORAGE OF MEAT

Introduction

Dehydration of meat during storage under refrigerated conditions contributes to a loss in quality and a significant economic loss due to the loss in weight.  The reason for dehydration is due to the fact that the surface of the meat is “exposed to heat and mass transfer exchange with the environment. The difference between the water vapour pressure on food surface and that in the air bulk is the driving force for dehydration.”  (Campanone et al, 2002)

Temperature and Weight

Campanone et al (2002) report that temperature and weight followed a similar behaviour with time. (see Graph 1)

Freezing and storage of meat.png
Graph 1

Internal Product Temperature

Campanone et al (2002) describe the results as shown in graph 1 as follows for internal product temperature.  “The internal product temperature curve presented three slope changes. The first coincided with the beginning of surface freezing, the second occurred at the end of the change of state whereas the last took place when the internal product temperature approaches the air temperature.”

Weight Loss

Campanone et al (2002) describe the results as shown in graph 1 as follows for weight loss.  “The weight loss curve displayed only one pronounced slope change when the temperature of the sample reached the air temperature.

Bustabad (1999) did a very useful study.  She chilled and then froze beef and pork, quarters or sides and stored it for six months, in stores with different cooling systems, different temperatures and in some cases, with covering. “Some meat was frozen without a previous chilling. The weight loss was determined and the results were statistically analysed by a multiple step-by-step regression.”  She analized weight and quality deterioration. The results of weight loss are reported in Table 1 below.  The air velocity was between 0.8 and 3 m/s and the temperatures between 20°C and 30°C.

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Table 1

“It is well known that evaporation of moisture from the outer layers of food in frozen storage results in significant weight losses (Rutov, 1955).  The percentage weight losses for a six-month period and their monthly averages obtained are presented in Table 2.

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Table 2

Carcass Size, Fat and Rind

Bustabad (1999) found that “forward quarters presented the greatest losses as the surface/volume ratio is greater, as also reported by Bailey (1971). Pork sides have lesser losses than beef due to their natural fat covering and skin; Cutting and Malton (1973) also reached similar conclusions.

 Boxing and Wrapping/ Bagging

The least losses were reported in the Bustabad study (1999) “by freezing boneless beef in boxes, and are minimal when the meat is wrapped in polyethylene bags. This was also proven by Washburn (1985). It is necessary, however, to consider the effects of packaging on prolonging the freezing time (Cutting, 1974).”

The effect of packing on weight losses is marked, decreasing it by more than 50%. Bailey (1976) recommended the use of polyethylene less than 0.05 mm thick, and in this case we used a 0.06 mm thick one. Plank and Kallert (1916) showed weight losses, for six-month storage, in beef quarters and pork sides with a weight similar to the samples used in this work when the temperature was 10°C. In both cases, the reported losses are greater despite being at a storage temperature of 13°C. It would be expected to be smaller from the work of Cutting and Malton (1974) on the relationship between the rate moisture evaporation and storage temperature.” (Bustabad, 1999)

Table 3 shows weiht loss under industrial conditions in the Bustabad study.  Cardboard boxes are recommended for storage because the shape stacks well and it reduces the weight loss (Stephen, Creed & Bailey, 1982).” (Bustabad, 1999)

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Table 3

Hot Freezing

“The hot pieces that were frozen had similar losses to the rest of the samples. In general, the results show greater losses than those reported by other authors such as Lorentzen and Rosvik (1959) and Manev (1983). This is influenced by the freezing conditions that in most of the cases are more severe and besides the quality of carcasses and their fat layers are greater (Cutting, 1974, 1976).”  (Bustabad, 1999)

Freezing Temperatures – Colder is Better and Wrapping is Best

Bustabad (1999) reports that an experiment (Experiment 3) was carried out under industrial conditions, “where the studied storage temperatures were 13°C and 18°C, in air-cooled stores. The resulting weight losses are included in Table 4.” The losses at 13°C are far greater than those of pieces stored at 18°C. If we compared the non wrapped and wrapped (in polyethylene) meat cuts, it can be seen that the effect of temperature decreased significantly when wrapped.  (Bustabad, 1999)

“Packing resulted in a highly significant effect; the greatest value in Experiment 3 indicates that it has a further importance if the pieces are hung on hooks. The coefficients related to the quarter factor indicate that the greatest weight losses occur in forward quarters and that stack storage diminishes this effect. This again corresponds to the observations of Bailey (1971) and the higher surface to volume ratio of such quarters. Non-chilled frozen quarters show greater losses during storage, and this is most significant in the case of hanging storage.”

The lesser weight losses occur at lower temperature storage, which is related to the difference between vapour pressure at the surface of the meat and surrounding air (Jasper & Placzek, 1978).  In the study of effects of interactions on weight losses, the use of packing diminishes them in forward quarters and its use has a greater importance if storage time and temperature are higher, and is more significant in chambers with greater air speed and hanging storage.” (Bustabad, 1999)

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Table 4

“Results obtained in this experiment can be compared to those by Sheffer and Rutov (1970). The ones included in Table 4 are greater. If we take results from polyethylene packing, the values of losses would be closer to those reported in the literature. Indeed, none of these references specify the weight of pieces used in the experiment.”  (Bustabad, 1999)

Increasing Airspeed by 1m/s

“Experiment 4, carried out in a chamber with an airspeed of 0.5 m/s and reported in Table 5 allows a comparison between the weight losses obtained at 18°C. The effect of the increase in airspeed is noticeable in increasing weight losses, which is not observed in those pieces packed in polyethylene.” (Bustabad, 1999)

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Table 5

Food Science Australia writes there is another problem with increased air velocity. “Higher air velocities enable more rapid chilling, but the fan power requirements increase by the cube of the air velocity. In most practical situations increasing the air velocity above 1 m/s cannot be justified by the small increase in cooling rate.”  (Food Science Australia)

A very good suggestion on how to handle this predicated on the way that cooling takes place.  “At the beginning, moisture loss is caused by liquid water evaporation during refrigeration. Then, as the surface becomes frozen, weight losses are due to ice sublimation. At both stages, the driving forces are the vapour pressure and temperature differences between food surface and the bulk air. As the sample approaches the external temperature, the temperature driving force disappears, so only the vapour pressure difference remains and the weight loss rate decreases.”  (Campanone et al,  2002)  Initial cooling happens due to the difference in temperature between the meat surface and the air temperature.  As the surface temperature reaches the air temperature after 8 – 10 hours of cooling, the rate of cooling becomes more dependant on the thermal conductivity of the meat and not the rate of transfer of heat from the meat surface to the air.  It will, therefore, make sense that the air velocity now be reduced to below 0.5m/s after 8 – 10 hours of beef chilling. Such a reduction will have little effect on the cooling rate but will have economic benefits by reducing weight loss and fan power consumption. (Food Science Australia)

“This is particularly important if the room is also required to operate as a storage chiller over weekends or longer periods.” (Food Science Australia)

Storage Time and Weight Loss

“In Table 6, regression coefficients for beef show the significance of the main effects (time, packing, temperature, previously chilled or non-chilled freezing and type of quarter) and are listed together with their interactions in each experiment. The corresponding constants of the regression equation, their correlation coefficients and the F-value in the regression analysis are also listed. Results show that the longer the storage time, the greater the losses due to evaporation. This effect has a greater influence in the case where the chamber has a greater airspeed (Experiment 4).”(Bustabad, 1999)

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Table 6

Combined effect of Time, Packaging, Temperature and Non-Chilled Freezing

“In the study on pork, the main effects considered were time, packing, temperature, non-chilled freezing and their interactions. Results are reported in Table 7. Regression coefficients for factors such as time, packing and temperature were highly significant. The highest times and greater temperatures have the greatest weight losses.”  (Bustabad, 1999)

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Table 7

“The use of packing diminishes losses. The highest value in Experiment 1 is related to storage conditions, higher temperatures (13°C) and forced air circulation. When comparing with the coefficients obtained for beef, it can be observed that packing is less important in the case of pork weight losses.

Coefficients for the effect of non-chilled or previously chilled freezing indicate that weight losses during storage are greater for non-chilled sides. The most important result in the study of interactions was that the use of packaging is more important if time and storage temperatures are higher. The adequacy of the models obtained is evident by observing the values of multiple correlation coefficients in each case and can also be checked by the analysis of residuals.”  (Bustabad, 1999)

Relative Humidity

Many equipment suppliers have recently emerged who offer solutions based on the impact of Relative Humidity on weight loss in carcass chillers.  “Relative humidity (RH) has a greater effect on weight loss than either air temperature or air velocity. Experimental work demonstrated that decreasing the humidity from 95% to 80% increased weight loss for beef sides by nearly 0.5% over an 18-hour chill. Therefore, for carcass chilling, the aim should be to keep the humidity as high as possible (above 90%) throughout the chilling cycle, particularly if carcasses are held for extended periods.

The cause of low RH in a chiller is usually related to the original plant design and the manner in which it is operated. If the evaporator is undersized, it may be necessary to use a low evaporating temperature in order to achieve the desired rate of heat removal. This will create a large difference between the evaporator coil temperature and the temperature of the air. The larger the temperature difference, the more moisture will be drawn from the air in the form of condensation on the coil. Undersized evaporators are usually a result of attempts to minimise capital costs in the original chiller construction.

The design and surface area of the finned coil evaporator will have a major influence on the chiller RH and, as a result, on the evaporative weight loss. Design of the finned coil is a complex subject with factors such as tube diameter and configuration, coil depth, surface area, refrigerant flow path, fin spacing, all having some effect on performance. The combination of the depth of the coil and the face area is one of the most important considerations. A shallow coil of adequate surface area will provide the best performance with respect to minimising weight loss.

Best results are achieved with coolers that are designed for a 3.0 to 3.5ºC difference between the refrigerant evaporating temperature and the entering air temperature, and an air temperature reduction through the coil of 0.5 to 0.8ºC.

The heat load in the room will be much higher at the beginning of the chilling cycle. The peak load can be more than three times the average heat load; therefore, during the latter part of the chilling cycle, the evaporators will be oversized. It is useful then to have the facility to modulate the refrigerant suction temperature through back-pressure control so that the air cooler operates at the highest possible suction temperature for the load. This will minimise the temperature difference between the coil and the air, resulting in the highest RH.

Spray Chilling

“Spray chilling of beef sides is used extensively in the United States and in some Australian plants. A major aim is the reduction of evaporative weight loss. A variety of spraying regimes has been used with longer periods of spraying resulting in less weight loss. Australian regulations require that no carcass shall have gained weight after chilling. Spray chilling for the first 6 to 10 hours of a 20-hour chilling cycle will result in an average carcass weight loss of 0.2 to 0.4% with no sides gaining weight.

Slightly faster cooling rates have been reported with spray chilling for the surface and the thinner sections of beef carcases when compared with conventional chilling. Researchers report that sides held for a further six days after overnight spray chilling lost less weight (3.2%) compared with conventional chilling (4.2%). Research also indicates that there is no significant difference between conventional and spray chilling in the quantity of weep in vacuum bags and the losses during retail display and cooking.”  (Food Science Australia)

Averages to use in Planning

It is good to know what effects weight loss and a loss in meat quality.  Many of the factors we have control over, but over many factors, we will have little control.  What are some averages that we can use in our planning or use as a general guide?

Here is a very helpful table from Food Science Australia, reporting on US figures.

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Sensory Assessment

“The results of the sensory assessment do not indicate quality losses which could be organoleptically detected. Moreover, rancidity was not found in any case, and there were not significant differences among the different storage conditions with regard to colour, flavour, and odour.

When comparing the toughness between non-chilled meats and previously chilled frozen meat, the toughest was non-chilled frozen beef. This can be explained by the phenomenon known as cold shortening (Taylor, Chrystall & Rhodes, 1972; Calvello, 1981; Mackie, 1993).  In the case of pork, this phenomenon was not recorded due to the fast decrease in pH after slaughter compared to beef (Bendall, 1972).

Different storage temperatures, use or not of wrapper and non-chilled or pre-chilled meat were compared. There were no significant differences between different storage conditions with regard to colour, taste and codour in any experiment.

Moreover, rancidity was not found to be significant in any case although it is known that one of the fundamental alterations in stored meat at temperatures below the freezing point is rancidity and it is more frequent in pork meat owing to larger susceptibility of their oils.

When comparing toughness between non-chilled meats and previously chilled frozen meat, it could be observed for beef in Experiment 1 that in the second month 14 judges found toughness in the frozen meat without previous chilling. Nevertheless, this was not significant because a minimum of 18 concurring scores are necessary for significance.

The judges preferred the toughness of previously chilled frozen meat at 2 and 4 months storage. After 6 months, 19 judges detected toughness in the non-chilled frozen meat, this result being significant. Likewise in Experiment 3, in the 4th Test, the results of comparing toughness were the following: 19 of the 20 judges detected the largest toughness in non-chilled meat freezing.

This sensory analysis results can be explained by the phenomenon known as cold shortening (Taylor et al., 1972; Calvello, 1981; Mackie, 1993; Bailey, 1976) thus limiting the use of rapidly lowering temperature in order to minimize weight loss. These results indicated that the conditions for this phenomenon to occur were present.  To avoid cold shortening, the meat should not reach 10°C before pH falls to 6.2, after slaughter.”  (Bustabad, 1999)

Van der Wal et al. (1995) reported that “losses in carcass weight, 24 h after conventional and forced chilling at -5°C, were about 2%. After ‘ultra’ rapid chilling (-30°C) the losses were reduced to 1.3% when air velocity was increased to 4 m/s. Meat quality of the longissimus lumborum muscle was not significantly affected by the various chilling regimes except for the variables related to tenderness. The Warner-Bratzler shear forces were higher (P < 0·05) together with shorter sarcomere lengths (P < 0·10) after ‘ultra’ rapid chilling at a high (4 m/s) air velocity, indicating an increased risk of cold shortening,” thus confirming the conclusion of Bustabad.

“When comparing toughness between non-chilled meats and previously chilled frozen meats, in the case of pork meat, significant differences were not found. These results agreed with most of the previous investigators, who have reported that cold shortening was not recorded in pork meat due to the fast decrease in pH after slaughter compared to beef (Bendall, 1972).

In the sensory evaluation, Experiment 4 chilled meat and frozen meat stored during 6 months were compared. The results did not indicate quality losses which could be organoleptically detected.”  (Bustabad, 1999)

Conclusion

We have seen different factors that affect the rate and degree of weight loss during freezing and storage of meat.

  • Surface/volume ratios such as in Beef FQ’s.
  • Fat and skin coverings in pork results in lower weight loss than beef or derined primals.
  • Storing meat in boxes and wrapping it in polyethylene bags (bags of less than 0.05 mm thickness is suggested).  Too thick bags will negatively affect the freezing rate.
  • Air temperature,
  • Air velocity, increases the rate of cooling
  • Relative humidity,
  • Carcase weight
  • Previously chilled meat
  • Relative Humidity

Food Science Australia offers the following practical suggestions.

  • Chill as rapidly as possible for the first few hours using low air temperature (~0ºC) and high velocity (approx. 1 m/s);
  • Reduce the air velocity to below 0.5 m/s after 8 to 10 hours for beef;
  • Install evaporator coils with adequate surface area and shallow depth;
  • Utilise modulating back pressure control to ensure that the coil is at the highest possible temperature for the current load.

Recommended Reading

Monitoring of Weight Losses in Meat Products during Freezing

Weight loss during freezing and the storage of frozen meat Ofelia Mendez Bustabad

The Freezing and Storage of Meat

References

Bustabad, O. M..  1999.  Weight loss during freezing and the storage of frozen meat, Department of Chemistry Engineering, School of Chemistry Engineering, Higher Polytechnic Institute “Jose Antonio Echevarria”, Havana, Cuba, Received 3 November 1997; accepted 16 March 1999.  Journal of Food Engineering 41 (1999) 1-11 Elsevier.

Campanone, L. A., Roche, L. A., Salvadori, V. O., Mascheroni, R. H..   2002.  Monitoring of Weight Losses in Meat Products during Freezing and Frozen Storage.  Food Sci Tech Int 2002;8(4):229–238, Sage Publications, ISSN: 1082-0132, DOI: 10.1106/108201302028555

Food Science Australia.  Evaporative weight losses during processing.   Meat Technology Update 3

Van der Wal, P. G., Engel, B., Van Beek, T. A., Veerkamp, C. H..  Chilling pig carcasses: Effects on temperature, weight loss and ultimate meat quality. December 1995. Meat Science 40(2):193-202 DOI:10.1016/0309-1740(94)00029-7 Source:PubMed

Photo credit:  https://www.indiamart.com/proddetail/chiller-meat-freezer-6220910012.html