Hi Guys,

Nutrition is a wonderful field of study with nothing staying as it was for long. Bigger better studies using more sophisticated equipment is continually unlocking natures secrets.

So, I started wondering about whether amino acids really get destroyed by the type of heat you would use in any form of cooking. Cooking does change the amino acid profile, but in this case, not destroy the amino acids.

http://www.pjbs.org/pjnonline/fin407.pdf

http://cat.inist.fr/?aModele=afficheN&cpsidt=19939353

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Amino Acid and Vitamin Composition of Raw and Cooked Horse Mackerel
Amino Acid and Vitamin Composition of Raw and Cooked Horse Mackerel
Journal Food Analytical Methods
Publisher Springer New York

SpringerLink Date Thursday, September 17, 2009


Amino Acid and Vitamin Composition of Raw and Cooked Horse Mackerel

Nuray Erkan1 Contact Information, Arif Selçuk2 Contact Information and Özkan Özden1 Contact Information
(1) Faculty of Fisheries, Department of the Seafood Processing and Quality Control, Istanbul University, Ordu cad. No:200, 34470 Laleli/Istanbul, Turkey
(2) Food Institute, TÜBİTAK Marmara Research Center, Gebze/Kocaeli, Turkey

Received: 27 May 2009 Accepted: 26 August 2009 Published online: 18 September 2009

Abstract Amino acid, vitamin (A, E, B1, B2, B3 and B6), and proximate composition were determined in raw and cooked horse mackerel. The changes in amino acid, vitamin, and proximate content were found to be significant for all cooking methods (frying, grilling, and steaming). Cooking did in general significantly increase the contents of essential, semi-essential, and other amino acids compared to raw fish species. Amino acid contents of grilled mackerel were significantly higher (p < 0.05) than those found in fried and steamed mackerel. The A, E, B2, and B6 vitamin content of fried horse mackerel was found to be significantly (p < 0.05) higher than the grilled and steamed samples. The B1 content of steamed and B3 content of grilled were found higher than the other cooked samples. Moisture, protein, fat, ash, and carbohydrate contents of cooked fish ranged between 56.52% to 61.34%, 20.79% and 23.93%, 13.44% and 19.61%, 1.70% and 2.47%, and 1.02% and 4.36 %, respectively. Fried fish had intermediate fat values, while grilled and steamed fishes had a comparatively low value.

Keywords Fish - Grilling - Frying - Steaming - Amino Acid - Vitamin - Proximate Composition


Food Chemistry
Volume 114, Issue 3, 1 June 2009, Pages 1074-1078


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Copyright © 2008 Elsevier Ltd All rights reserved.
Analytical Methods
Determination of aromatic amino acid content in cooked meat by derivative spectrophotometry: Implications for nutritional quality of meat



References and further reading may be available for this article. To view references and further reading you must purchase this article.

Ph. GatellierCorresponding Author Contact Information, a, E-mail The Corresponding Author, A. Kondjoyana, S. Portanguena, E. Grèvea, K. Yoona and V. Santé-Lhoutelliera

aINRA, UR370 QuaPA, Centre de Theix, F-63122 Saint Genès Champanelle, France

Received 11 March 2008;
revised 26 August 2008;
accepted 7 October 2008.
Available online 15 October 2008.

Abstract

The technique of second derivative spectrophotometry was used to determine the level and the heat stability of the three aromatic amino acids (tryptophan, tyrosine and phenylalanine) in bovine meat (M. Longissimus thoraci). This paper presents a method which measures the second derivative absorbance values at a wavelength specifically assigned to each aromatic amino acid with corrections for the interference from other amino acids at the same wavelength. Three cooking temperatures were tested in this study (60, 100 and 140 °C). Due to important cooking losses, results differ slightly according to the method of calculation (level expressed by gram of wet meat or by gram of proteins). Whatever the calculation method, heating at 60 °C had little effect on aromatic acid levels while higher temperatures had a dramatic effect on aromatic amino acids stability. The stability of the three aromatic amino acids during cooking decreased in the order tryptophan > phenylalanine > tyrosine.

Keywords: Meat; Cooking; Second derivative spectrophotometry; Tryptophan; Tyrosine; Phenylalanine
Article Outline


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