Valuable Ca/P Sources Obtained from Tuna Species’ By-Products Derived from Industrial Processing: Physicochemical and Features of Skeleton Fractions

Round 1

Reviewer 1 Report

Comments and Suggestions for Authors

Valuable Ca/P sources obtained from tuna species´ by-products derived from industrial processing: Physicochemical and features of skeleton fractions

The authors presented the work well and easy to understand. There is a significant potential to extract Ca/P from industrial canned tuna fish by products, the hydrolysis and chemical extraction followed by controlled calcinations were well presented and results reasoning are well organized and explained.

 

See my comments below.

Line 46: correct to “tuna”

Line 137-139: How do these values compare with the existing literature studies? Would it be possible to add a couple of sentences in comparison.

Line 160-161: Please add a reference choosing this methodology

Line 198-201: Please reword these sentences, it violates the scientific explanation, or criticizing is not recommended in other words use of “does not make sense” is not recommended.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf

Reviewer 2 Report

Comments and Suggestions for Authors

The manuscript presents a study on the recycling of mineral fractions from tuna species, specifically yellowfin tuna (YF) and Katsuwonus pelamis (SKJ). The research focuses on the chemical composition and physicochemical characterization of calcium phosphates extracted from different parts of the tuna skeletons, including the head, branchial arch, viscera, central skeleton, caudal fin, dorsal fin, and scales. The authors employ various analytical techniques such as X-ray diffraction (XRD), Raman spectroscopy, and X-ray fluorescence (XRF) to characterize the crystalline structures and elemental composition of the extracted calcium phosphates. The study also discusses potential applications of these mineral fractions in industries such as biofertilizers and adsorbents for environmental remediation. 

Two minor concerns include:

1) Introduction: The authors mention the main chemical composition of the samples, but it would be helpful to provide a brief overview of the significance of hydroxyapatite and whitlockite/β-tricalcium phosphate in the context of fish bones.

2) The discussion section: It would be beneficial to include a more in-depth discussion on the implications of the observed biphasic composition in the heads of both tuna species.

Author Response

Please see the attachment.

Author Response File: Author Response.pdf