Cholesterol Oxidation in Fish and Fish Products

Abstract

Fish and fish products are important from a nutritional point of view due to the presence of high biological value proteins and the high content of polyunsaturated fatty acids, especially those of the n-3 series, and above all eicosapentaenoic acid and docosahexaenoic acid. However, these important food products also contain significant amounts of cholesterol. Although cholesterol participates in essential functions in the human body, it is unstable, especially in the presence of light, oxygen, radiation, and high temperatures that can cause the formation of cholesterol oxidation products or cholesterol oxides, which are prejudicial to human health. Fish processing involves high and low temperatures, as well as other methods for microbiological control, which increases shelf life and consequently added value; however, such processes favor the formation of cholesterol oxidation products. This review brings together data on the formation of cholesterol oxides during the preparation and processing of fish into food products which are recognized and recommended for their nutritional properties.

Use of Natural Antioxidants in the Inhibition of Cholesterol Oxidation: A Review

“…Fish and fish products Fish are noted for their high levels of polyunsaturated fatty acids of the omega-3 series, such as eicosapentaenoic acids (EPA, C20: 5) and docosahexaenoic acids (DHA, C22: 6), which are compounds directly related to health benefits (Calder, 2015;Haimeur Raatz, Silverstein, Jahns, & Picklo, 2013;Zheng, Hu, Zhao, Yang, & Li, 2013). However, the lipid fraction of fish, which is composed mainly of PUFAs and with high levels of cholesterol, is particularly susceptible to oxidation processes when exposed to favorable factors during processing and storage (Dantas et al, 2015;Freitas et al, 2015;Márquez-Ruiz & Morales, 2015;Saldanha et al, 2008). In addition, the presence of pigments, such as myoglobin and hemoglobin, and traces of metal ions in fish makes this food matrix more susceptible to oxidation.…”

“…The most common COPs present in foods are 7‐ketocholesterol, 20α‐hydroxycholesterol, 25‐hydroxycholesterol, α, β‐epoxycholesterol and 7α, 7β‐hydroxycholesterol (Hur et al., ; Orczewska‐Dudek et al., ). The profile of the products formed and their concentrations are influenced by factors such as water activity, oxidation time, pH, exposure to light and irradiation, elevated temperatures, physical state of cholesterol, and food composition (presence of unsaturated fatty acids) (Barnaba, Rodríguez‐Estrada, Lercker, García, & Medina‐Meza, ; Dantas et al., ; Medina‐Meza & Barnaba, ).…”

Impact of Air Frying on Cholesterol and Fatty Acids Oxidation in Sardines: Protective Effects of Aromatic Herbs

“…However, some authors have demonstrated that sardines also contain high levels of cholesterol (Saldanha and others ; Scherr and others ). These 2 types of compounds, n ‐3 PUFAs and cholesterol, are not chemically stable and this instability is influenced by their chemical structure, the presence of oxygen, light, metal ions, and the processing techniques (heat) used, among other factors (Dantas and others ; Barriuso and others ).…”

“…The temperature used and the time required to prepare fish and fish products are perhaps the main factors that contribute to the degradation of cholesterol, forming cholesterol oxidation products (COPs) (Dantas and others ; Leal‐Castañeda and others ). These substances are structurally similar to cholesterol and are normally present in small quantities formed by endogenous metabolic processes.…”

“…These substances are structurally similar to cholesterol and are normally present in small quantities formed by endogenous metabolic processes. However, the exogenous cholesterol oxides formed during the processing of food can be potentially harmful to health (Dantas and others ) and these COPs are associated with the development of cardiovascular and neurodegenerative diseases, besides inflammation, atherosclerosis, mutagenesis, carcinogenesis, and cell death (Doria and others ; Barriuso and others ).…”