When is fresh meat repeated

No interactive effects were observed on TCC in this study Table Total yeast-mould count Yeast-Mould count was also satisfactory level in this study. The initial yeast-mould count for control was 2. Depending on the degree of processing following slaughter their spoilage time varies between 2 and 8 d under refrigeration Marenzi, After thawing frozen beef samples evaluated by a trained and untrained panel were found to have lower intensity of beef color, odor, juiciness, tenderness and overall acceptability compared to fresh beef samples.

However, panel evaluations of the sensory attributes showed significant p 0. The results of the present study were in agreement with Sen and Sharma reported that panelists found that the freeze thaw cycles did cause significant deterioration in color and odor of meat samples.

Sensory scores for appearance, flavor, tenderness, juiciness and overall acceptability of the beef samples remained similar till cycle two Fig. A gradual decline of these attributes might be due to the expected loss of moisture and volatile components from samples and condiments on storage of beef. Freezing procedures influence thawing loss, color and tenderness of beef Farouk and Swan ; Honikel et al. Beef color is one of the key selection criteria for consumers making their purchase decisions and important indicator of the processing suitability of meat.

Consumers use color as an indicator of meat freshness or even eating quality Mancini and Hunt, ; Ngapo et al. Whipple and Koohmaraie stated that freezing temperature and rate as well as thaw rate may affect the extent to which aging meat after freezing improves tenderness, because of possible detrimental or beneficial effects of freezing itself.

The results of the present study were in agreement with previous reports. Freezing and thawing rates have significant effects on Warner Bratzler shear force or sensory tenderness. Lee et al. When meat is frozen, ice crystals form inside the cells of muscle tissue and puncture the cell walls. If meats refrozen accelerating further moisture loss, and, when this meats eventually cook, any one may find it dense and dry in texture. The result of this experiment is also related to Lui et al.

Lui et al. The moisture content of beef trimmings were established as Freezing and thawing alter both the content and the distribution of moisture in beef tissue. Moisture as a quality characteristic in meat can be evaluated in several ways, including thaw loss, drip loss, cooking loss, water holding capacity and total moisture contents.

Changes in thaw loss, drip loss, cooking loss and water holding capacity WHC during repeated freeze-thaw cycles and interactive effects of treatments and cycles are presented in Table The amount of thaw loss may be a measure of damage to muscular tissue structure in the freezing process, reflecting the effectiveness of different thawing methods Kondratowicz et al. Thawing methods had no significant effect on beef weight loss.

Thaw loss was increased with repeated freeze-thaw cycles. This finding agrees with Muela et al. The range of thaw loss was 3.

According to Xia et al. In case of drip loss all treatments showed a significant change over the course of the trial. In this study, drip loss was within In general, drip loss was decreased with the number of repeated freeze-thaw cycles.

Drip loss is exacerbated by cutting, heating, grinding, pressing, and particularly freeze-thawing. Up to Exudates drip or thaw loss are closely related to muscle protein oxidation and denaturation which are responsible for muscle pH decline, discoloration, and toughness Traore et al. Moreover, changes of drip or thaw loss are also interlinked with the rate of pH and the temperature decline post mortem, the rate of post mortem glycolysis, the degree of actomyosin cross-linking during rigir mortis, residual ATP levels final pH and the activity of a multitude of enzymes Lawrie, On the other hand, the loss of exudates drip or thaw loss from beef is unavoidable, because some loss of moisture occurs due to the presence of water in a free form in muscle tissue Joo and Kim, during freeze-thaw.

Amount of exudates can be reduced to a minimum by controlling WHC Jeong et al. Both drip loss and cooking loss were affected by freezethawing p Another important functional property of beef is WHC, in particular water absorption and retention by the protein structures of muscular tissue as well as water retention during heat processing HuffLonergan and Lonergan In general freezing, frozen storage and thawing all contribute to a decrease in the water-holding capacity of meat Vieira et al.

An initial increase and a subsequent decrease in WHC have been reported Joo et al. WHC was also affected by thawing methods and the combined effect of thawing methods and freeze-thawing cycles. Except cycle 3 the result of WHC in this study was satisfactory which agreed to Nasreen et al. Inappropriate freezing and thawing may significantly deteriorate the ultimate quality of meat.

Meat used for industrial purposes most often thawed naturally in the atmospheric air or under uncontrolled conditions.

This process may lead to considerable moisture losses and alter the physicochemical properties of beef Kondratowicz et al. This might be due to inhibition of microbial growth at frozen storage. A significantly low pH value was observed during thawing in tap water in freeze-thaw cycle 3 pH 5. The decrease in pH due to freezing and thawing most likely arose from the loss of minerals and small protein compounds as exudates, thereby changing the ionic balance in the beef which resulted in a decreased pH Vieira et al.

This result was also in agreement with Jun et al. Further researches are required to examine the influence of repeated freeze-thaw cycles on beef pH concerned with different methods and rate of thawing.

Fresh meat undergoes major undesirable changes during storage at both refrigeration and freezing temperatures. Lipid peroxidation is one of the primary mechanisms of quality deterioration in stored foods, especially in muscle tissues. Lipid oxidation is a major factor that determines the sensory, functional, and nutritional quality of beef and beef products. TBARS is a secondary oxidation product commonly used as a measurement of lipid oxidation.

The secondary by-products of lipid oxidation such as aldehydes have generated cytotoxic and genotoxic properties due to their high reactivity. TBA and peroxide values increased significantly during storage time and they correlated positively with each other. Lipid oxidation is an important quality parameter for meat and meat products, because it may lead to rancidity Jin et al.

When beef and beef products are stored under frozen conditions, microbial spoilage may be delayed but fat deterioration occurs and the beef constituents may be oxidized. A general trend of increase in TBARS during refrigerated and frozen storage of meat and meat products has been reported by many workers Devatkal et al.

TBARS value increased slowly within the cycles and among the cycles by thawing methods in present study. The oxidative stability of meat depends upon the balance of anti and pro-oxidants, and the composition of oxidation substrates including polyunsaturated fatty acids PUFA , cholesterol, proteins, and pigments Bertelsen et al. Beef is a rich source of these compounds.

Heat disrupts the muscle cell structure, and inactivates antioxidative enzymes and releases oxygen from oxymyoglobin. High temperature decreases the activation energy for oxidation and breaks down hydroperoxides to free radicals, which propagate lipid peroxidation. Heating seemed to be very pro-oxidative for the pre-frozen meat samples as measured by the high TBARS values.

This statement supports the results of present study. The initial value of TVC for control in beef was 5. No significant increase in growth of organisms occurred during 11 wk of frozen storage when compared to microbial growth at 0 d of storage for all treatments Fig. This could be due to lower pH and no available nutrients favorable for microbial growth. Another similar study Marriott et al. From the results of the present study, it may be concluded that, as the number of repeated freeze-thaw cycles increased it affected the sensory, physicochemical quality and microbiological quality of beef muscle, causing the deterioration of beef quality, but improving the microbiological quality.

Click here to choose a searching target image or drag and drop a searching target image. Article Info. Abstract The objectives of this study were to know the effect of repeated freeze-thaw cycles of beef on the sensory, physicochemical quality and microbiological assessment.

The thawing loss increased and dripping loss decreased significantly p. Keywords repeated ; freeze-thaw ; cycle ; beef ; quality ; safety ; sensory. Introduction Nowadays different preservation methods of meat have been developed among which freezing is most useful over the world Sultana et al.

Physicochemical properties of beef Thaw loss Thaw loss was determined by weighing each whole muscle prior to freezing and again after thawing and blotting dry with tissue paper. Water holding capacity Muscle water-holding capacity WHC was determined by the filter paper press method Grau and Hamm, Measurement of lipid oxidation The lipid oxidation value of beef was determined by the methods of Buege and Aust and Ahn et al.

Results Sensory evaluation Color The color of the samples was observed after thawing before cook and after cook in each freeze-thaw cycles 1- 3. Odor The odor was almost similar to control but differed by different thawing methods within and among the cycles before cook Fig. Physicochemical properties Thaw loss Fresh unfrozen and unthawed samples had no thaw loss.

Drip loss was affected p Cooking loss The initial cooking loss of fresh sample was Cooking loss was affected p Water holding capacity WHC A significant difference was noted for WHC among beef samples subjected to repeated freeze-thaw cycles.

WHC was affected p Measurement of pH The pH of the meat influences the rate of oxidation as well as the microbial shelf life and drip loss and vice versa.

TVC was affected significantly p Fig. Total yeast-mould count Total yeast-mould count Yeast-Mould count was also satisfactory level in this study. Physicochemical properties Measurement of moisture loss The moisture content of beef trimmings were established as Measurement of lipid oxidation Fresh meat undergoes major undesirable changes during storage at both refrigeration and freezing temperatures.

Conclusion From the results of the present study, it may be concluded that, as the number of repeated freeze-thaw cycles increased it affected the sensory, physicochemical quality and microbiological quality of beef muscle, causing the deterioration of beef quality, but improving the microbiological quality.

References Ahn, D. Meat Sci. AMSA Research guidelines for cookery, sensory evaluation, and instrumental tenderness measurements of fresh meat. Chicago III.

Berry, E. Food Prod. Bertelsen, G. In Proceedings of the 46th international congress of meat science and technology 4. Bing, L. Food Eng. Methods Enzymol 52, Academic press Inc. Ultrasonics Sonochemistry. Food Sci. Food Res. Irish J. Devatkal, S. Elkhalifa, E. Die Naturwissenschaften 40, The Netherlands. Jay, J. Jeong, J. LWT Food Sci. Jiangsu J. Joo, S. In Joo ST Ed. Jun, Q. A project of the American Meat Science Association.

Ask a Meat Scientist. The amount of myoglobin in animal muscles determines the color of meat. Lamb and Pork are classified as "red" meat along with beef and veal as they contain more myoglobin than chicken or fish, which is considered "white" meat. When fresh pork is cooked, it becomes lighter in color, but it is still a red meat.

Raw poultry can vary from a bluish-white to yellow. Younger poultry has less fat under the skin, which can cause the bluish cast, and the yellow skin could be a result of marigolds in the feed. Featured Meat Scientist Paul Clayton. Video Podcasts and Webinars Grass or grain? Is there a definitively sustainable beef production system? Social Media. See you at noon!