Quality and Safety of Pork Steak Marinated in Fermented Dairy Products and Sous-Vide Cooked
Round 1
Reviewer 1 Report
The aim of the study was to determine the impact of using marinade (yoghurt, kefir and buttermilk) on some physicochemical and microbiological characteristics of the pork steak that was cooked for 6 hours (sous-vide in 60oC and 80oC).
The Authors show interesting results, however, I have doubts about the microbiological part of the research. In the paragraph 3.4. (lines 276-288) as well as in the introduction (lines 31-35), the Authors discuss the impact of using meat marinade on extending the shelf-life of the steak. The data presented in the article, though, show only the total counts of bacteria after cooking and do not include the storage stability results.
According to studies (Armstrong and McIlveen, 2000, Betts and Gaze, 1995, Church, 1998, Creed, 1995, González-Fandos et al., 2004, González-Fandos et al., 2005, Hansen et al., 1995, Mossel and Struijk, 1991, Nyati, 2000a, Peck, 1997, Peck and Stringer, 2005, Rybka-Rodgers, 2001, Simpson et al., 1994, Vaudagna et al., 2002) sous-vide cooking itself extends the shelf-life of food products, what is more, the combination of proper temperature and cooking time make the product safe.
I suggest to either skip presenting the microbiological results and focus on other characteristics or, if the Authors conducted storage studies, show the results.
I would also refer to language and editorial details in the text given. The language used is understandable, however, I would do another proof reading as there are small grammar/spelling mistakes. I also suggest to pay more attention to details. For example:
“yogurt” was used 6 times and “yoghurt” – 16 times, line 44: “EC” and rest of the text “KE”, lines 170, 171, 296: oC.Author Response
We would like to thank you for the contributions to our manuscript. We accepted all the suggestions and made the alterations as recommended. Please find below some complementary answers to the reviewer’ comments, considering all the changes required. All the alterations suggested by Reviewers are marked in red (Reviewer 1) or green (Reviewer 2) along the manuscript. The parts/words deleted are not showed. Even so, we would be happy to revise and rework the paper to meet the standards of publication if necessary.
P1. The Authors show interesting results, however, I have doubts about the microbiological part of the research. In the paragraph 3.4. (lines 276-288) as well as in the introduction (lines 31-35), the Authors discuss the impact of using meat marinade on extending the shelf-life of the steak. The data presented in the article, though, show only the total counts of bacteria after cooking and do not include the storage stability results.
Answer P1: In these studies, we wanted to check the impact of meat marinating time in FDP on selected chemical characteristics and microbiological safety of a sous-vide cooked meat product. to our knowledge, this topic has not yet been studied by scientists. In the literature you can find information on the impact of the combination of time and temperature of processing different types of meat by the sous-vide method on microbiological stability during storage of the finished meat product. Our product was intended to be served to consumers the next day after heat treatment. Therefore, we have not studied the effect of storage time after heat treatment on microbiological stability
P2. According to studies (Armstrong and McIlveen, 2000, Betts and Gaze, 1995, Church, 1998, Creed, 1995, González-Fandos et al., 2004, González-Fandos et al., 2005, Hansen et al., 1995, Mossel and Struijk, 1991, Nyati, 2000a, Peck, 1997, Peck and Stringer, 2005, Rybka-Rodgers, 2001, Simpson et al., 1994, Vaudagna et al., 2002) sous-vide cooking itself extends the shelf-life of food products, what is more, the combination of proper temperature and cooking time make the product safe. I suggest to either skip presenting the microbiological results and focus on other characteristics or, if the Authors conducted storage studies, show the results.
Answer P2: We removed the table with the results of microbiological analysis. We decided to leave in the manuscript information that all samples had after cooking SV satisfactory microbiological quality
P3. I would also refer to language and editorial details in the text given. The language used is understandable, however, I would do another proof reading as there are small grammar/spelling mistakes. I also suggest to pay more attention to details. For example: “yogurt” was used 6 times and “yoghurt” – 16 times, line 44: “EC” and rest of the text “KE”, lines 170, 171, 296: oC.
Answer P3: Has been corrected
Author Response File: 
Author Response.pdf
Reviewer 2 Report
The general idea was acceptable but it was poorly justified in the introduction. Material and methods must to be improved as well the discussion. English grammar (and I suspect that also original grammar) must be improved. I suggest to the authors to read more paper before to improved the manuscript and to try to write the paper in good scientific language. All the manuscript needs a deep revision.
Details in the manuscript.
Comments for author File: Comments.pdf
Author Response
We would like to thank you for the contributions to our manuscript. We accepted all the suggestions and made the alterations as recommended. Please find below some complementary answers to the reviewer’ comments, considering all the changes required. All the alterations suggested by Reviewers are marked in red (Reviewer 1) or green (Reviewer 2) along the manuscript. The parts/words deleted are not showed. Even so, we would be happy to revise and rework the paper to meet the standards of publication if necessary.
Line 34: “…we suggest marinating the meat,…” but, then, the final product is other...A1. The final product is a meat steak marinated in fermented dairy products and then cooked sous-vide
Line 34: “…fermented dairy products „ why by diary products?. You must to explained the source of the idea. Dou you have an excedent of dairy products, for example?.
A2. Excerpts from the text below were placed in the manuscript:
Meat marinating is a commonly used treatment that improves the culinary properties of meat (Mozuriene, et al., Effect of natural marinade based on lactic acid bacteria on pork meat quality parameters and biogenic amine contents. LWT – Food Science and Technology, 2016, 69, 319-326; Pathania, et al., Antimicrobial activity of commercial marinades against multiple strains of Salmonella spp. International Journal of Food Microbiology, 2010, 139, 214-217; Yusop, et al., Effect of marinating time and low pH on marinade performance and sensory acceptability of poultry meat. Meat Science, 2010, 85, 657-663; Żochowska-Kujawska, et al., Effects of fibre type and kefir, wine lemon, and pineapple marinades on texture and sensory properties of wild boar and deer longissimus muscle. Meat Science, 2012, 92, 675-680.). Meat is usually marinated by soaking in an acid solution to improve tenderness, taste and smell (Yusop et al., 2010) or to extend the shelf life of the product by limiting the growth of bacteria, especially pathogenic ones (Pathania et al., 2010). Many authors of the above studies confirm beneficial effect of marinating on sensory characteristics of meat, its texture, juiciness and durability. This is mainly due to the impact of low marinade pH on meat (Goli, et al., Evolution of pH during immersion of meat protein matrices in acidic marinades. Meat Science, 2012, 90, 618-623). Natural kefir is a healthy, milky refreshing drink, developed in the process of milk-alcohol fermentation. Traditionally, it is produced by inoculating milk with kefir grains. The grains contains live cultures bacteria LAB (Lactobacillus, Lactococcus, Leuconostoc, Acetobacter and Streptococcus sp.) and yeasts (Saccharomyces, Candida, Torula and Kluyveromyces sp.) Kefir is a natural source of calcium (120 mg / 100 g product). It also helps to regulate the operation of the alimentary canal. Natural yoghurt contains the living cultures of Lb. bulgaricus and Str. thermophilus bacteria, which increase the level of naturally occurring, beneficial bacteria in the body that support digestion. These bacteria have a positive effect on intestinal flora, improve digestive comfort, help maintain bacterial balance in the intestines and improve the function of the digestive tract and normalize intestinal perestaletics. It contains 170 mg of calcium in 100 g of the product. Traditional buttermilk was the liquid left behind after churning butter out of cultured cream. Commercially available cultured buttermilk is milk that has been pasteurized and homogenized, and then inoculated with a culture of Lc. lactis plus Leuc. citrovorum to simulate the naturally occurring bacteria in the old-fashioned product. It contains 116 mg of calcium in 100 g of the product. Rich in lecithin, proteins and mineral salts. Thanks to the lactic acid content, it enhances the secretion of gastric juices, stimulates and regulates the digestive processes. The meat marinating offered by us in fermented milk products may additionally increase these effects. Presence of calcium ions in fermented dairy products can activate calpains, increasing meat tenderness. This is confirmed by research conducted by Żochowska-Kujawska et al. (2012). Also the presence of live lactic acid bacteria cultures (LAB) can increase the durability of marinated meat (Ben Fadhel et al., Combined effects of marinating and γ-irradiation in ensuring safety, protection of nutritional value and increase in shelf-life of ready-to-cook meat for immunocompromised patients. Meat Science, 2016, 118, 43-51; Mozuriene et al. 2016). LABs produce antimicrobial metabolites, including organic acids and bacteriocins (Fadda, et al., Role of lactic acid bacteria during meat conditioning and fermentation: peptides generated as sensorial and hygienic biomarkers. Meat Science, 2010, 86, 66-79). These metabolites prevent from development of pathogenic microorganisms and making the meat spoilage, and also contribute to color stabilization and texture improvement (Olaoye and Idowu, Features and functional properties of lactic acid bacteria used as biological preservatives of meat processing: a review article. Journal of Agricultural Science and Technology, 2010, 6, 449-460).
Line 38: “Fermentation makes the pH of FDP is around 4.” but this could to lead a sensory problem
A.3. Meat is usually marinated by soaking in an acid solution to improve tenderness, taste and smell (Yusop et al., 2010) or to extend the shelf life of the product by limiting the growth of bacteria, especially pathogenic ones (Pathania et al., 2010). Many authors of the above studies confirm beneficial effect of marinating on sensory characteristics of meat, its texture, juiciness and durability. This is mainly due to the impact of low marinade pH on meat (Goli, et al., 2012).
Line 44: “…the EC, YO or BM …” why those three and no others?
A.4. We chose kefir, yogurt and buttermilk because they are widely available, very popular, relatively cheap and most consumed fermented milk products in Europe.
Line 46: “microbiological characteristics” - and colour? and sensory?
A5. The results of the color and sensory evaluation were presented in another manuscript, titled “Effect of meat marinating in kefir, yoghurt and buttermilk on the texture and color of pork steaks cooked sous-vide” which is currently being reviewed.
Line 49: “Great White Poland pigs” - males, females, it does not matter?
A.6. Pigs breed Great White Poland, from 4 months of age, regardless of sex, are intended for fattening. After reaching a weight of over 100 kg, i.e. at the age of over 6 months, they are slaughtered.
Line 49: “120–130 kg” - is this the usual slaughter weight for the breed?
A7. Pigs of the Great White Poland breed are most often slaughtered after obtaining a weight of 120-130 kg
Line 50: “the slaughterhouse” - what kind of slaughterhouse, what was the distance between the farm and the salighterhouse? what was the handling of the animals prior to the slaughter?
A.8. Slaughter of animals carried out in accordance with the requirements of the European Union, ie. Council Regulation (EC) No 1099/2009 of 24 September 2009 on the protection of animals at the time of killing. Official Journal of the European Union L 303/1
Line 50: “Central part of” - what means "central part"?. Please, explain it in anatomical terms
A.9. The description has been supplemented with an anatomical name (m. Longissimus dorsi thoracis),
Line 51: “…homogeneous histological structure…” what is an homogeneus structure? Dou you means without fat or connective tissue, for exmaple?
A.10. This sentence has been deleted.
Line 51: “The muscles …” All the muscle, the whole muscle? How many samples per animal?
A.11. The middle part of the loin, Longissimus dorsi thoracis, was used for the study. Twelve loins were cut into 96 steaks = 8 samples (KE6, BM6, YO6, C6 KE8, BM8, YO8, C8) x 4 storage times (3, 6, 9 or 12 days) x 3 replicates. - Has been completed in the text.
Line 54: “…were added …” - in what physical state? Liquid, solid, how?
A.12. Fermented dairy products were added in a natural liquid form
Lines 54-55: “…kefir (KE), buttermilk (BM) or yoghurt (YO) in an amount of 10% in relation to the meat mass.” - How do you acurate that dairy product was homogeneously distributed? If you put a piece of buttermilk in a bag, the part of the loin in contact had more buttermilk than the opposite side.
A.13. Fermented dairy products have a high viscosity. Very well, even layer adheres to the meat immersed in them. The meat after immersion in FDP was put into bags and weighed. If necessary, FDP was topped up so that the FDP mass constituted 10% of the meat mass. The pouches were then vacuum-sealed.
On the other side, this 10%, was weight/weight, even in the case of kefir?
A.14. Yes, this 10%, was weight / weight, even in the case of kefir
Line 55: “… a steak …” only one or one per animal?
A.15. has been corrected
Line 57: “…at 4 °C.” in dark?
A.16. Of course in the dark. Has been completed in the text
Line 58: “… 60 °C or 80 °C for 6 hours. “ - the half at 60ºC and the other half at 80ºC? How was monitored the internal temperature of the steaks?
A.17. Two water baths were used in the study. One was kept at 60 °C, the other at 80 °C. Appropriate samples were placed in a suitable bath. There was no need to monitor the temperature inside the steaks because: a) the steaks were relatively thin (3 cm), b) the thermal treatment was long-lasting (6 hours), c) the temperature of the water in the bath was kept constant - in accordance with the principles of physics and our knowledge , steak temperature had to be 60 °C or 80 °C, respectively.
Line 62: “Processing …” - Then, cooking losses. Processing losses would implie the whole weight loss, that is, storage+cooking
A.18.The processing loss was calculated by measuring the difference in the weight of the raw steak before marinating and the marinated (for the appropriate time) steak after cooking sous-vide, chilled, removed from the bag and dried on the filter paper. - has been completed
Line 63: “The moisture content …” - at this moment, after cooking?
A.19. The moisture content was determined in cooked samples - - has been completed
Line 65: „Chemical composition …” - when, at slaughter, before cooking, after cooking? how many samples per animal?
A.20. Has been supplemented in the title of chapter 2.3.
Line 90: „Chemical analysis” - when?
A.21. Has been supplemented
Line 98: „(…Elmetron, Poland).” - please, insert a reference of the used method
A.22. Has been supplemented
Line 99: “Water activity” - you must to explain it more detailed. When, how many samples, a reference of the method...?
A.23. In our opinion, the data provided are sufficient. In many publications, in reputable magazines, only the data we provide are given, e.g.
Stadnik, J., Dolatowski, Z.J. Biogenic amines content during extended ageing of dry-cured pork loins inoculated with probiotics. Meat Science 2012, 91, 374-377.
Ruiz-Capillas, C., et al. Konjac gel as pork backfat replacer in dry fermented sausages: Processing and quality characteristics. Meat Science, 2012, 92, 144-150.
Kacaniová M., et al. Environmental concentration of selected elements and relation to physicochemical parameters in honey. Journal of Environmental Science and Health, Part A, 2009, 44, 414-422.
Line 103: „…substances' (TBARS)…” - insert a reference for the method
A.24. Has been supplemented
Line 127: „… Chemical analyses were performed in three replicates…” – this may to be placed before, in material and methods.
A.25. has been corrected
Line 127: „… fix effect of treatments …” - please, specify what are they? Used dairy product and temperature? anything else?
A.26. has been completed
Line 128: „… replications …” - replication was a random effect of ypu have calculated a mean of the three measures?
A.27. Steaks for individual samples were selected randomly. Three steaks were selected for each sample. Each steak was repeated three times for a given chemical analysis.
Line 129: „… SAS …” - version?
A.28. has been completed
Line 138: „… of cooking.” - p value, please
A.29. has been completed
Line 139: „… at 60 °C.” - why? what is the explanation, your hypothesis?
A.30. In our opinion, the interaction of a complex system such as FDP, which contains proteins, fats, live bacterial cultures, low pH, high calcium content, etc. can cause unexpected reactions with the ingredients of raw meat. The longer the FDP effect on meat, the processes that take place, e.g. proteolytic, may have a more unexpected nature. Changes occurring in raw meat due to marinating in FDP require further study. However, it has been proven that acidic marinating of meat affects the structure of muscle tissue, and thus its tenderness.
Yusop, et al. Effect of marinating time and low pH on marinade performance and sensory acceptability of poultry meat. Meat Science, 2010, 85, 657-663.
Goli, et al. Mass transfer dynamics during the acidic marination of turkey meat. Journal of Food Engineering, 2011, 104, 161–168e,
Huang, et al. Impact of citric acid on the tenderness, microstructure and oxidative stability of beef muscle. Meat Science, 2009, 82, 113-118.
Ke, et al. Impact of citric acid on the tenderness, microstructure and oxidative stability of beef muscle. Meat Science, 2009, 82, 113–118.
Goli, et al. (2014). Influence of sodium chloride and pH during acidic marination on water retention and mechanical properties of turkey breast meat. Meat Science, 96(3), 1133–1140.)
Żochowska-Kujawska et.al. Effects of fibre type and kefir, wine lemon, and pineapple marinades on texture and sensory properties of wild boar and deer longissimus muscle. Meat Science, 2012, 92, 675-680
Mozuriene, et.al. Effect of natural marinade based on lactic acid bacteria on pork meat quality parameters and biogenic amine contents. LWT – Food Science and Technology, 2016, 69, 319-326.
Kargiotou, et al. Efficacies of soy sauce and wine base marinades for controlling spoilage of raw beef. Food Microbiology, 2011, 28, 158-163.
Tsai, et.al. Changes in Muscovy duck breast muscle marinated with ginger extract. Food Chemistry 2012, 130 316-320.
Jinap, et.al. Effect of organic acid ingredients in marinades containing different types of sugar on the formation of heterocyclic amines in grilled chicken. Food Control, 2018, 84 ,478-484.
Feng, et.al. Effects of adding red wine on the physicochemical properties and sensory characteristics of uncured frankfurter-type sausage. Meat Science, 2016, 121, 285–291.
In our case it may be similar. Lower temperature of meat heat treatment causes milder changes in protein structures. Different groups of meat proteins react in different ways to temperature (Palka, K., Daun, H. Changes in texture, cooking losses, and myofibrillar structure of bovine M. semitendinosus during heating. Meat Science, 1999, 51, 237-243, Sanchez del Pulgar, et al. Physico-chemical, textural and structural characteristic of sous-vide cooked pork cheeks as affected by vaccum, cooking temperature and cooking time. Meat Science, 2012, 90, 828-835). Changes in proteins due to e.g. low pH and the impact of live bacterial cultures, can modify the susceptibility of meat proteins to temperature effects. Hence the significant differences in the weight loss of steaks cooked at 60 °C.
Lines 142-143: „… It was found that weight losses of steaks marinated in KE, YO and BM for 3, 6 or 9 days and SV cooked were significantly …” - this is no true. For example: in meat marinting during 3 days and cooked at 60ºC, YO6 was no different from the cntrol. KE6 or BM6 were no different from the control, KE8 was no different from the control....etc.
A.31. Has been corrected
Line 146: „…standard …” - sure? standard error or typical deviation? Please, explain it
A.32. Of course, standard deviation. Wherever necessary has been corrected
Line 151: „… Loss of mass …” - weight loss. The same terminology along the whole paper
A.33. Has been corrected along the whole paper
Lines 156-158: ”… 62 °C also causes changes in the perimysial of connective tissue. Contraction of the connective tissue causes the compression of muscle fiber bundles, which deepens the process of water separation.” - insert a reference.
A.34. Has been completed
Lines 158-159: “… cooking method or directly in water does not affect the juiciness of meat.” - really?
A.35. Sanchez del Pulgar, J.; Gazquez, A.; Ruiz-Carrascal, J. Physico-chemical, textural and structural characteristic of sous-vide cooked pork cheeks as affected by vaccum, cooking temperature and cooking time. Meat Science, 2012, 90, 828-835.: “…All these steps basically agree with the temperature effect detected in packaged cheek samples in this study, in which the higher the temperature, the greater the water losses and the lower the moisture content. Interestingly enough, unpackaged samples cooked in boiling water for 30 min showed similar water losses to packaged samples cooked at 80 °C in the circulating bath. Thus, one of the advantages claimed by sous-vide meat cooking chefs, a greater juiciness due to a more concentrated retention of juices, does not seem to be directly related to the cooking method (either sous-vide or unpackaged in boiling water). Instead, the advantage is more likely derived from the cooking temperature used. In fact, when considering water losses in either vacuum packaged or air packaged samples, the former showed slightly but significantly greater water losses, evidencing that vacuum cooking per se does not cause a greater juice retention in meat…”
Line 160: “Vacuum cooking itself does not cause more juice retention in the meat.” - and less?
A.36. We do not understand the attention
Lines 162-163: “…partial exudation of surface water caused by the vacuum.” - if this is true, please, insert a reference
A.37. Has been completed
Lines 164-166: „Using the SV method, losses of these components are reduced, which if the cooking temperature exceeds the collagen solubility temperature, are bound in the gelatin structure after cooling [4].” - and? if you have gelatin, it implies a weight reduction or a weight gain? Because gelatin retains water...
A.38. No, in the case when we have a tightly closed system, e.g. in a vacuum, as in the case of our examination
Line 169: „… steaks cooked at 80 °C.” - p value?
A.39. Has been completed
Line 171: „ No effect of marinating…” - p value, please
A.40. Has been completed.
Line 173: „ …samples marinated in KE.” - p value, please. And in the figure it is impossible to appreciate this differences....
A.41. Has been completed.
Line 173: „ The method of steaks processing …” - what is "the method of processing"?. Marinating? time? both?
A.42. The processing method includes both the type of marinade used, marinating time and SV cooking temperature. Each of the analyzed samples has a different processing method, which is described in chapter 2.1. Raw material preparation.
Lines 180-182: „ … collagen, mainly perimysium. During cooking, swollen muscle fibers maintain high degree of water binding; they are also more resistant to thermal shrinkage due to lower thermal sensitivity of collagen.” - and?. link these sentences with ypur results, please. a paper is not a conjoint of copied phrases, is a discussion about the possible causes for found results.
A.43. We think the sentences are correct
Line 192: “… KE is around 4.2 due …” - ???? The global means for KE is 5,64. Please explain this 4.2.
The global means for KE is 5,64???
A.44. Generally, fermentation of dairy products is carried out until the casein isoelectric point is reached, i.e. pH 4.6. In scientific publications, the authors give a kefir pH value of about 4.2:
Athanasiadis, et al. Development of a novel whey beverage by fermentation with kefir granules. Effect of various treatments. Biotechnology Progress, 2004, 20 1091-1095.
Kwak, et al. Biostabilisation of kefir with a nonlactose-fermenting yeast. Journal of Dairy Science, 1996, 79937-942.
Zajsek, K., Gorsek, A. Effect of natural starter culture activity on ethanol content in fermented dairy products International Journal of Dairy Technology, 2010, 63, DOI: 10.1111/j.1471-0307.2009.00549.x,
Line 193: “…YO is 4.4 …” - idem
A.45. In scientific publications, the authors give a yoghurt pH value of about 4.4.
Pothuraju, et al. Chapter 29 - Fermented milk in protection against inflammatory mechanisms in obesity. [in:] Immunity and inflammation in health and disease: emerging roles of nutraceuticals and functional foods in immune support (ed.) Chatterjee, S., Jungraithmayr, W., Bagchi, D., 2018, 389-401, Academic Press, New York (pH 4.6)
Tomovska, et al. Examination of pH, titratable acidity and antioxidant activity in fermented milk. Journal of Materials Science and Engineering, 2016, 6, 326-333 (pH 6.67 to 4.19)
Karagul, et al. Formulations and processing of yogurt affect the microbial quality of carbonated yogurt. Journal of Dairy Science, 2001, 84, 543-50. (“Samples were incubated at 43 degrees C until pH values of 5.0 or 4.2 were reached. Strawberry yogurts at low (4.2) and high (5.0) pHs were divided into three portions”)
Sfakianakis, P., Tzia C., Conventional and innovative processing of milk for yogurt manufacture; development of texture and flavor: A Review Foods, 2014, 3, 176-193. (pH 5)
Arioui, et al. Physicochemical and sensory quality of yogurt incorporated with pectin from peel of Citrus sinensis. Food Science and Nutrition, 2017, 5, 358-364.
Lines 195-196: “…pH of about 4.5. “ - I undesrtand that 4.5 is the pH of the buttermilk, of the origianl product, no the pH of meat, isn't it?.
A.46. Well you understood, “BM is a by-product of whipping the sweet cream into butter, produced with the participation of Lactococcus and Leuconostoc, and it has a pH of about 4.5.”
Gebreselassie, N., et al.Chemical composition of naturally fermented buttermilk. International Journal of Dairy Technology, 2016, 69, 200-208. (pH 4,43)
Skryplonek, , et al., The use of buttermilk as a raw material for cheese production. International Journal of Dairy Technology, 2019, https://doi.org/10.1111/1471-0307.12614. (pH 4,2)
Sodini, I., et al. Compositional and functional properties of buttermilk: a comparison between sweet, sour, and whey buttermilk. Journal of Dairy Science, 2006, 89, 525-36.
Line 199: “Marinating in YO lowered the pH of steaks to the largest extent.” - I don't understand what dou you want to express...
A.47. Has been corrected in the text
Lines 209-210: “…The aw value in raw meat is 0.99, whereas in meat products after heat treatment it amounts from 0.93 to 0.97. In these studies, …” - insert a reference
A.48. Has been completed
Lines 213-214: “…research periods. However, significant effect of the marinating duration on aw 213 was recorded. The aw value was the smaller, the longer the marinating …” - p value
A.41. Has been completed
Lines 217-218: “…molecules by enzymes and bacteria contained in meat and in fermented dairy products added to marinating.” - This is a suposition, because you have no measured them.
A.50. That's why it was written: “…may result from decomposition of meat chemical components, mainly proteins, into smaller molecules by enzymes and bacteria contained in meat and in fermented dairy products added to marinating.”
Lines 221-222: “…In addition, dairy products are a source of calcium that acts as a post mortem activator of calpaines [25].” - and? what is the importance of this for your work?
A.51. Because: “… aw depends, among others, on the quantity and quality of food ingredients, a significant reduction in its level .. may result from decomposition of meat chemical components, mainly proteins, into smaller molecules by enzymes and bacteria contained in meat and in fermented dairy products added to marinating.”
Line 231: “…higher …” - p value!!!!!
A.52. Has been completed
Line 232: “…value of 3 mg MDA/kg.” - which is the threshold.....bla, bla, bla...you must to link the results with the explnaition!
A.53. We do not understand the attention
Line 236: “…marinade.” - and what about authors that use marinates?
A.54. Nobody has used such a marinade as suggested by us
Other authors cited by us who used other marinades did not examine this indicator in meat products
Table 6. really, no detected?
A.55. We removed the table with the results of microbiological analysis. We decided to leave in the manuscript information that all samples had after cooking SV satisfactory microbiological quality
Author Response File: 
Author Response.docx
Round 2
Reviewer 2 Report
Many of the proposed corrections or modifications have been included but not all. Mainly in the sample preparation, authors must to explain how dairy products were added to samples. On the other hand, the sentence "Central part of the muscle 54 with a homogeneous histological structure was excised" must to be replaced, as commented in the first revision: samples must to be described in anatomical terms. And, in this wasy, the name of the muscle is Lonsigissimus thoracis et lumborum.On the other hand, the authors must explain why they have used dairy products to marinate the meat since as they themselves explain, it is not the usual product used for this purpose. This comment was yet included in the first revision.
Conclusions are too long and then, they can be improved. Conclusions are not a resume of the results but the most important result and their practical implications. Finally, I would recommend an English grammar revision.
Author Response
Reviewer 2
We would like to thank you for the contributions to our manuscript. We accepted all the suggestions and made the alterations as recommended. Please find below some complementary answers to the reviewer’ comments, considering all the changes required. All the alterations suggested by Reviewer 2 are marked in green along the manuscript. The parts/words deleted are not showed.
Even so, we would be happy to revise and rework the paper to meet the standards of publication if necessary.
Q1. Mainly in the sample preparation, authors must to explain how dairy products were added to samples.
A1. Has been completed in the text.
Q2.On the other hand, the sentence "Central part of the muscle 54 with a homogeneous histological structure was excised" must to be replaced, as commented in the first revision: samples must to be described in anatomical terms.
A2. This sentence has been deleted.
Q3. And, in this wasy, the name of the muscle is Lonsigissimus thoracis et lumborum
A3. Has been completed in the text.
Q4. On the other hand, the authors must explain why they have used dairy products to marinate the meat since as they themselves explain, it is not the usual product used for this purpose. This comment was yet included in the first revision.
A4. Has been completed in the text.
Q5. Conclusions are too long and then, they can be improved. Conclusions are not a resume of the results but the most important result and their practical implications.
A5. The conclusions has been improved.
Q6. Finally, I would recommend an English grammar revision.
A6. English grammar has been improved
Author Response File: Author Response.docx
