Comparative Life Cycle Assessment of Two Different Packaging Systems for Extra-Virgin Olive Oil: Glass Bottle vs. 100% Recycled Polyethylene Terephthalate (PET) Bottle
Round 1
Reviewer 1 Report
Manuscript ID: sustainability-2204932
Comparative LCA of two different packaging systems for extra-virgin olive oil: glass bottle vs 100% recycled PET bottle
The manuscript is of general interest. The following comments should help further improve the quality of the work:
1-Please avoid using abbreviations in the abstract if they are used once or twice only.
2-Please include a Table of Abbreviations/Nomenclatures.
3-Abstract should be improved by including the main numerical findings of the study.
4-The manuscript should be improved in terms of the usage of English. Authors are advised to get their manuscript edited by a native English speaker or by a Professional English Editing Service.
5-Using too short paragraphs should be avoided.
6-The novelty/originality of the paper should be more effectively established. It would be advisable to add a Table to the “Introduction” section, tabulating the latest research works in the field to highlight the novelty of the present work accordingly.
7-The uncertainties associated with the application of LCA should be briefly mentioned where LCA is introduced in the Introduction section using the latest works concerning the application of this technique, including “On quantifying sources of uncertainty in the carbon footprint of biofuels: crop/feedstock, LCA modelling approach, land-use change, and GHG metrics”, etc.
8-Please avoid using Abbreviations in headings and sub-heading throughout the manuscript.
9-Please carry out sensitivity analysis.
10-More comparison of the results obtained with those of previous studies and critical discussion should also be added.
11-In figures: please place proper labels and units on the X and Y axes. There should be proper labels (which are missing in their current state), and then units should be placed in parentheses. For instance, in Figure 3: please do not repeat the % symbol next to each value on the Y axis; instead, add a proper label like “Label (%)”.
12-The same comment applies to Figure 4.
13-Future efforts should also include investigating the sustainability features of the findings reported using other advanced sustainability assessment tools such as exergy analysis and its extensions, i.e., exergoeconomic and exergoenvironmental analysis, as elaborated in a recent work “The role of sustainability assessment tools in realizing bioenergy and bioproduct systems”. Authors can consider including the mentioned works to highlight the importance of such assessments and to direct future studies.
14-Please change "4. Conclusions" to "4. Conclusions and prospects". Accordingly, please elaborate on the future research needs in this domain.
15-The limitations of the study should also be explained.
16-The practical implication of the present study should be included and discussed as well.
Author Response
Manuscript ID: sustainability-2204932
Type of manuscript: Article
Title: Comparative LCA of two different packaging systems for extra-virgin olive oil: glass bottle vs 100% recycled PET bottle
Replies to Reviewers' comments:
Reviewer #1:
The manuscript is of general interest. The following comments should help further improve the quality of the work:
Comment 1-Please avoid using abbreviations in the abstract if they are used once or twice only.
Authors’ response:
The comment has been accepted.
Most abbreviations have been removed by the abstract
Comment 2-Please include a Table of Abbreviations/Nomenclatures.
Authors’ response:
The comment has been accepted.
A list of abbreviations has been included in the manuscript.
Comment 3-Abstract should be improved by including the main numerical findings of the study.
Authors’ response:
The comment has been accepted.
Numerical findings have been added in the abstract of the manuscript.
Revised text:
Lines 18-22:
“… for which life cycle impacts of the R-PET were lower than 40% compared to those of the glass system. In terms of global warming, the glass system was responsible for 790 – 1137 kg CO2 eq. (in function of the destination country considered); while the R-PET system, in the same conditions, showed impacts of 459 – 634 kg CO2 eq.”
Comment 4-The manuscript should be improved in terms of the usage of English. Authors are advised to get their manuscript edited by a native English speaker or by a Professional English Editing Service.
Authors’ response:
The paper was revised by an English native speaker dealing with scientific articles since more than 25 years..
Comment 5-Using too short paragraphs should be avoided.
Authors’ response:
The comment has been accepted.
The issue has been solved; too short paragraphs have included in other sections.
Comment 6-The novelty/originality of the paper should be more effectively established. It would be advisable to add a Table to the “Introduction” section, tabulating the latest research works in the field to highlight the novelty of the present work accordingly.
Authors’ response:
The comment has been accepted and a new table with previous research papers on the topic has been added in the Introduction section.
See new Table 1.
Revised text:
Lines 86-87:
“Table 1 reports the main details of the above mentioned LCA studies concerning the comparison of the environmental performances of the PET and glass packaging systems.”
Comment 7-The uncertainties associated with the application of LCA should be briefly mentioned where LCA is introduced in the Introduction section using the latest works concerning the application of this technique, including “On quantifying sources of uncertainty in the carbon footprint of biofuels: crop/feedstock, LCA modelling approach, land-use change, and GHG metrics”, etc.
Authors’ response:
The comment has not been accepted.
The suggested paper has not been included in the manuscript because it is not inherent to the purpose of the study.
Comment 8-Please avoid using Abbreviations in headings and sub-heading throughout the manuscript.
Authors’ response:
The comment has been accepted.
The issue has been solved; the use of abbreviation has been avoided in headings and sub-heading.
Comment 9-Please carry out sensitivity analysis.
Authors’ response:
The comment has not been accepted.
The results about the environmental performances of the two packaging systems are so far apart that the variation of some sensitive parameters would not have a significant effect.
Comment 10-More comparison of the results obtained with those of previous studies and critical discussion should also be added.
Authors’ response:
The comment has been accepted.
More comparison of the obtained results with those of other LCA studies has been added.
Revised text:
Lines 284-287:
“… Similar results were reported also in the study of Kouloumpis et al. (2020) [25] highlighting the high sustainability of the glass as a recyclable material. Indeed, glass can be recycled countless times without deterioration of the material quality [25].”
Lines 307-311:
“Looking at the first four scenarios (S1 G_CH; S2 P_CH; S3 G_DK; S4 P_DK) in which a EVOO distribution in European country was considered, the primary packaging production provided the highest contribution to the total impact for both the packaging systems for all the impact categories considered. Similar results were showed in the studies of Cleary (2013) [22] and Stefanini et al. (2020) [28].”
Lines 319-322:
“These findings are in line with the GWP impacts reported in the study of Stefanini et al. (2020) [28] related to the secondary-tertiary packaging of glass and R-PET systems (90 g CO2 eq and 37.7 g CO2 eq. respectively, considering the packaging of 1 liter of milk).”
Comment 11-In figures: please place proper labels and units on the X and Y axes. There should be proper labels (which are missing in their current state), and then units should be placed in parentheses. For instance, in Figure 3: please do not repeat the % symbol next to each value on the Y axis; instead, add a proper label like “Label (%)”.
Authors’ response:
The comment has been accepted.
The figure 3 has been modified adding the Y axes label.
Comment 12-The same comment applies to Figure 4.
Authors’ response:
The comment has been accepted.
The figure 4 has been modified adding the Y axes label.
Comment 13-Future efforts should also include investigating the sustainability features of the findings reported using other advanced sustainability assessment tools such as exergy analysis and its extensions, i.e., exergoeconomic and exergoenvironmental analysis, as elaborated in a recent work “The role of sustainability assessment tools in realizing bioenergy and bioproduct systems”. Authors can consider including the mentioned works to highlight the importance of such assessments and to direct future studies.
Authors’ response:
The comment has been accepted.
The suggested paper has been added discussing the mentioned aspect.
Revised text:
Lines 393-396:
“… Furthermore, future studies could contribute to the topic also combining the LCA methodology with other sustainability assessment tools such as energy, emergy and exergy analysis. For instance, the study of Aghbashlo et al. (2022) [46] showed that the integration of more methodologies can provide more reliable results than single approaches.”
Comment 14-Please change "4. Conclusions" to "4. Conclusions and prospects". Accordingly, please elaborate on the future research needs in this domain.
Authors’ response:
The comment has been accepted.
In the Conclusions section a new sub-section has been added: “4.1. Limitations of the study and future researches” in which the future research needs have been reported.
Revised text:
Lines 388-396:
“…. In this sense, next to the LCA methodology, very used tools as Life Cycle Costing (LCC) and Social Life Cycle Assessment (SLCA) are available to estimate the economic and social impacts respectively [45]. Therefore, it would be interesting to carry out future researches in order to assess the sustainability of EVOO packaging alternatives integrating the three aspects.
Furthermore, future studies could contribute to the topic also combining the LCA methodology with other sustainability assessment tools such as energy, emergy and exergy analysis. For instance, the study of Aghbashlo et al. (2022) [46] showed that the integration of more methodologies can provide more reliable results than single approaches.”
Comment 15-The limitations of the study should also be explained.
Authors’ response:
The comment has been accepted.
The limitations of the study have been added and explained in a new specific sub-section: “4.1. Limitations of the study and future researches”
Revised text:
Lines 382-388:
“4.1. Limitations of the study and future researches
The study assessed the environmental performances of two EVOO packaging systems through the application of the LCA methodology. Therefore, the obtained results showed only the life cycle environmental impacts of the systems, while the eco-nomic and social aspects of the sustainability are missing. Nevertheless, for an effective sustainability assessment of alternative systems, the environmental, economic, and social aspects should be integrated [39]. ….”
Comment 16-The practical implication of the present study should be included and discussed as well.
Authors’ response:
The comment has been accepted.
The practical implications of the obtained results have been reported more clearly.
Revised text:
Lines 347-349:
“… through innovative communicative initiatives, needed to allow the consumers to go beyond prejudices and commonplaces directing them towards more informed purchasing choices”.
Author Response File: 
Author Response.pdf
Reviewer 2 Report
This manuscript assessed the environmental sustainability of two packaging systems for extra virgin olive oil (EVOO) such as glass bottle and 100% recycled PET bottle using the Life Cycle Assessment (LCA) methodology. The innovation of this manuscript is weak. So this manuscript requires revision.
1. In Introduction section, the authors should improve these sections to better describe the innovativeness. The authors should compare Navarro et al. (2018) and Salomone et al. (2013) with your study in order to demonstrate how your study is different from those that have already been published, and how your paper can fill the knowledge gap.
2. P3, line 116, what is the full name of FU? Please provide it.
3. In Table 1, why do the authors only provide the transport by sea of R-PET granulate for PET bottles, while the parameters by sea of other packaging systems are not provided?
4. In Results and Discussion section, the authors should analyze the reasons more deeply. In addition, I suggest adding subheading to discuss.
5. In Fig.3, what are the full names of these abbreviations on the x-axis, for example SDO, IR, OF, HH, etc? Please provide them.
6. In Table 5, “Impacts referred to the FU of the study (1000 l of EVOO).”, it should be “(1000 L of EVOO)”.
Author Response
Manuscript ID: sustainability-2204932
Type of manuscript: Article
Title: Comparative LCA of two different packaging systems for extra-virgin olive oil: glass bottle vs 100% recycled PET bottle
Replies to Reviewer' comments:
Reviewer #2:
This manuscript assessed the environmental sustainability of two packaging systems for extra virgin olive oil (EVOO) such as glass bottle and 100% recycled PET bottle using the Life Cycle Assessment (LCA) methodology. The innovation of this manuscript is weak. So this manuscript requires revision.
Authors’ response:
The comment has been accepted.
The manuscript has been modified according to the reviewer’s suggestions.
Comment 1. In Introduction section, the authors should improve these sections to better describe the innovativeness. The authors should compare Navarro et al. (2018) and Salomone et al. (2013) with your study in order to demonstrate how your study is different from those that have already been published, and how your paper can fill the knowledge gap.
Authors’ response:
The comment has been accepted.
The main difference with the previous studies about the PET bottles production (virgin or recycled) has been underlined in the manuscript; furthermore, a new table with the main characteristics of the previous research papers on the topic has been added.
Revised text:
Lines 76-77:
“…However, the two previous studies on the EVOO packaging analysed PET produced with only virgin PET granulate.”
Lines 86-87:
“Table 1 reports the main details of the above mentioned LCA studies concerning the comparison of the environmental performances of the PET and glass packaging systems.”
Comment 2. P3, line 116, what is the full name of FU? Please provide it.
Authors’ response:
The comment has been accepted
The full name of FU (functional unit) has been provided in the manuscript.
Comment 3. In Table 1, why do the authors only provide the transport by sea of R-PET granulate for PET bottles, while the parameters by sea of other packaging systems are not provided?
Authors’ response:
The reason is that only for R-PET granulate is needed a transport by sea because of the location of the providers of this material; however, as shown in the mentioned Table, R-PET granulate needed also a transport by road for about 184 km.
Comment 4. In Results and Discussion section, the authors should analyze the reasons more deeply. In addition, I suggest adding subheading to discuss.
Authors’ response:
The comment has been accepted.
The results have been analysed more deeply, increasing the comparison of them with the findings obtained by other previous papers on the topic. Nevertheless, the review’s suggestion on the use of subheading has not been accepted because it doesn't seem fit for discussion of these results.
Revised text:
Lines 284-287:
“… Similar results were reported also in the study of Kouloumpis et al. (2020) [25] highlighting the high sustainability of the glass as a recyclable material. Indeed, glass can be recycled countless times without deterioration of the material quality [25].”
Lines 307-311:
“Looking at the first four scenarios (S1 G_CH; S2 P_CH; S3 G_DK; S4 P_DK) in which a EVOO distribution in European country was considered, the primary packaging production provided the highest contribution to the total impact for both the packaging systems for all the impact categories considered. Similar results were showed in the studies of Cleary (2013) [22] and Stefanini et al. (2020) [28].”
Lines 319-322:
“These findings are in line with the GWP impacts reported in the study of Stefanini et al. (2020) [28] related to the secondary-tertiary packaging of glass and R-PET systems (90 g CO2 eq and 37.7 g CO2 eq. respectively, considering the packaging of 1 liter of milk).”
Comment 5. In Fig.3, what are the full names of these abbreviations on the x-axis, for example SDO, IR, OF, HH, etc? Please provide them.
Authors’ response:
The comment has been accepted.
The full names of the categories acronyms have been added in the caption of Figure 3; furthermore, a list of acronyms has been included in the manuscript.
Comment 6. In Table 5, “Impacts referred to the FU of the study (1000 l of EVOO).”, it should be “(1000 L of EVOO)”.
Authors’ response:
The comment has been accepted.
the caption of the Table 5 (now Table 6) has been modified according to the comment.
Author Response File: Author Response.pdf
Reviewer 3 Report
The paper is clear and the conclusions are basically correct and reliable, which has basically reached the acceptance level of the journal. I have no further comments. Good luck.
Author Response
Manuscript ID: sustainability-2204932
Type of manuscript: Article
Title: Comparative LCA of two different packaging systems for extra-virgin olive oil: glass bottle vs 100% recycled PET bottle
Replies to Reviewer' comments:
Reviewer #3:
The paper is clear and the conclusions are basically correct and reliable, which has basically reached the acceptance level of the journal. I have no further comments. Good luck.
Authors’ response:
Many thanks for your positive comment.
Author Response File: Author Response.pdf
Reviewer 4 Report
well-constructed manuscript, however, can be made more appropriate by defining the abbreviations.
Comments for author File: Comments.pdf
Author Response
Manuscript ID: sustainability-2204932
Type of manuscript: Article
Title: Comparative LCA of two different packaging systems for extra-virgin olive oil: glass bottle vs 100% recycled PET bottle
Replies to Reviewer' comments:
Reviewer #4:
Well-constructed manuscript, however, can be made more appropriate by defining the abbreviations.
Authors’ response:
Many thanks for your comments
The manuscript is convincing and has great importance on geotechnical Sustainability of olive oil life cycle. The manuscript is well construted. However, this manuscript can be improved based on the following comments.
Authors’ response:
Many thanks for your comments
In title the full form of LCA and PET is not specified for common unknown readers. Is this LCA or LCAI through LCA?
Authors’ response:
The comment has been accepted.
The required full forms of LCA (Life Cycle Assessment) and PET (Polyethylene terephthalate) have been specified in the title.
- In abstract section, the author have mentioned PET materials (line 12), however, its full form is not mentioned anywhere in the manuscript.
Authors’ response:
The comment has been accepted.
The full form of PET (Polyethylene terephthalate) has been added in the title of the manuscript, in the list of abbreviations and in the Introduction section.
- In keywords, the LCA or LCIA is missing. I think this is the main idea of the research.
Authors’ response:
The comment has been accepted.
The word LCA has been added of the keywords
- In figure 1, the abbreviation written in left hand site of the scenarios has not mentioned in the legend. I would like to suggest the author to write the actual indication of them.
Authors’ response:
The comment has been accepted.
More details about the meaning of the abbreviations in Figure 1 have been added in the figure caption.
- Line 116, author have mentioned about FU, without its proper defining.
Authors’ response:
The comment has been accepted.
A definition of the Function Unit (FU) has been added in the text.
Revised text:
Lines 138-140:
“…the functional unit (FU) of the study (i.e. a quantified description of the performance requirements that the product system fulfils) was defined on the basis of a volume of EVOO”.
- In figure 2, what is ‘T’?
Authors’ response:
The comment has been accepted.
The meaning of T (Transport) has been added in the caption of Figure 2.
- I would like to suggest to put abbreviation section in this manuscript
Authors’ response:
The comment has been accepted.
A list of abbreviations has been included in the manuscript.
- Support the conclusions with your specific objective.
Authors’ response:
The comment has been accepted.
The conclusion section has been expanded adding other considerations.
See the new “Conclusions” section.
Author Response File: Author Response.pdf
Round 2
Reviewer 1 Report
The manuscript can be accepted for publication.
Reviewer 2 Report
I have no questions.
