Formation of Plant Sterol Oxidation Products in Foods during Baking and Cooking Using Margarine without and with Added Plant Sterol Esters

Abstract

Plant sterols (PS) in foods are subject to thermal oxidation to form PS oxidation products (POP). This study measured POP contents of 19 foods prepared by typical household baking and cooking methods using margarines without (control) and with 7.5% added PS (as 12.5% PS-esters, PS-margarine). Median POP contents per portion size of cooked foods were 0.57 mg (range 0.05-1.11 mg) with control margarine versus 1.42 mg (range 0.08-20.5 mg) with PS-margarine. The oxidation rate of PS (ORP) was 0.50% (median) with the PS-margarine and 3.66% with the control margarine. Using the PS-margarine, microwave-cooked codfish had the lowest POP content, with 0.08 mg per portion, while shallow-fried potatoes had the highest POP content, 20.5 mg per portion. Median POP contents in cookies, muffins, banana bread, and sponge cake baked with the control or PS-margarine were 0.12 mg (range 0.11-0.21 mg) and 0.24 mg (range 0.19-0.60 mg) per portion, with a corresponding ORP of 1.38% and 0.06%, respectively. POP contents in all the cooked and baked foods did not exceed 20.5 mg per typical portion size. A wide variation in the distribution of individual POP among different foods existed, with 7-keto-PS and 5,6-epoxy-PS being the major oxidation products.

Effect of DL-Methionine Supplementation on Tissue and Plasma Antioxidant Status and Concentrations of Oxidation Products of Cholesterol and Phytosterols in Heat-Processed Thigh Muscle of Broilers

“…Correlation analysis revealed an inverse relationship between the concentration of vitamin C in thigh muscle and the concentrations of POPs in heat-processed thigh muscle, indicating that the slightly increased concentrations of vitamin C in muscle of broilers supplemented with DLM in comparison the control broilers could be responsible for a reduced formation of POPs. Although POPs are poorly absorbed in the small intestine, they are suggested, like COPs, to be atherogenic, and therefore their intake via foods requires attention [9,44]. However, it has to be noted the concentrations of total POPs in heat-processed thigh muscle being in the range between 3.5 and 4 pmol per g (equivalent to 0.875 to 1.00 µg/100 g) of thigh muscle are much lower than in other foods, such as plant oils (0.5 to 7 mg/100 g in different samples of corn oil or sunflower oil), or products baked with margarines, such as cookies or muffins (0.2-0.7 mg/100 g) [13,45].…”

Development and validation of methodologies for the quantification of phytosterols and phytosterol oxidation products in cooked and baked food products

“…The PS contents found for the different groups of foods prepared with control and PS-margarine are summarized in Table 9. The full range of data obtained for the entire sample set including discussions on the nutritional consequences is beyond the scope of the current article and will be presented elsewhere [31]. Below a small summary of the analytically most interesting findings and areas of attention is presented.…”

“…A summary of the quantitative results is given. Detailed quantitative results on the sterols and sterol oxides present, including the consequences for blood cholesterol levels, are presented elsewhere [31].…”

Serum Concentration of Plant Sterol Oxidation Products (POP) Compared to Cholesterol Oxidation Products (COP) after Intake of Oxidized Plant Sterols: A Randomised, Placebo-Controlled, Double-Blind Dose–Response Pilot Study

“…Similarly, Lin et al [14] estimated an upper POP intake of 48 mg/d based on a daily PS intake of 3 g/d (advised upper intake level) and a reported oxidation rate of PS (90% quantile) of 1.6%. Based on the measured POP contents of a variety of prepared foods such as meats, fish, vegetables, eggs, and potatoes, Lin et al [18,19] estimated a daily POP intake of 7 mg/d (median; range 0.3‒64 mg/d), assuming one portion of such prepared foods is consumed per day. Taking these data together [14,15,18,19], the upper (90‒95% quantile) POP intake ranges between 25 and 48 mg/d, with the highest intake of 64 mg/d when using PS-added margarines for frying.…”