Recent advances in assessment of marine lipid oxidation by using fluorescence

Abstract

Lipid changes during food processing are important because of their impact on the final product quality. Lipid damage detection is limited because of the ability of lipid oxidation products (i.e., hydroperoxides and carbonyl compounds) to produce interaction compounds by reacting with nucleophilic food constituents. Fluorescence quantification at a single excitation/emission maximum of these interaction compounds has been employed in a qualitative way as a complementary tool for food quality assessment. The present work reviews recent research where simultaneous detection at different excitation/emission maxima was employed to assess lipid oxidation and quality changes during fish processing. A fluorescence shift towards a higher wavelength maxima was detected as a result of lipid damage; the shift was calculated as the ratio (δF) between two of the maxima tested (393/463 nm and 327/415 nm) and was investigated along different fish processes (freezing and frozen storage, refrigerated storage, cooking, and canning) and in complementary model systems where the influence of different factors (time and temperature of processing, amine and aldehyde composition and content, formaldehyde presence, and pH value of the medium) was checked. Determination of the δF value provided better results for quality change assessment in fish products than most of the lipid quality indices, in addition to being rapid and sensitive.Paper no. J8840 in JAOCS 74, 409-419 (April 1999).

Effect of partially hydrolysed lipids on inhibition of oxidation of marine lipids

“…Lipid oxidation compounds (e.g., peroxides and carbonyls) produced from CLO during the present experiment interacted with Pam to produce Schiff bases and other interaction compounds that were assessed by fluorescence and browning detections (25,28,29). In the absence of CLO+Pam, no changes in both assessments were observed along the reaction time; this was the case of the individual reagent blanks (CLO, Pam, CA, MG and DG) and also the mixtures Pam+MG and Pam+DG, including different reagent ratios (data not shown).…”

Development of a quality index scheme and shelf-life study for whole tambaqui (Colossoma macropomum)

“…The biological proteins decrease because of reactions with the amine groups of lysine, the oxidation of methionine, and other amino acids changes (Tironi et al 2009), and it is also related to texture modifications by crosslinking polypeptide chains (Aubourg 1999). Thus, proteases and microorganisms cause natural degradation of myofibrillar proteins and collagen and explain how the muscle becomes weak during ice storage (Ando et al 1999).…”

Lipid hydrolysis and oxidation in farmed gilthead seabream (<i>Sparus aurata</i>) slaughtered and chilled under different icing conditions

“…However, lipid damage development was found low, according to the different lipid quality indexes considered (lipid hydrolysis; primary, secondary and tertiary lipid oxidation), these the gilthead seabream muscle (Pokorný, 1981;Aubourg, 1999) (Table 3). Similar conclusions were obtained for both fluorescence and browning property assessments.…”

“…important peroxide content decrease is observed, being likely to be produced as a result of partial peroxide breakdown into other kinds of lipid oxidation compounds (Pokorný, 1981;Aubourg, 1999). Highest mean PV obtained (days 7 and 11 for individuals corresponding to SI and FI, respectively) remain below a 10 value and can not be considered especially high.…”