Preliminary study on health-related lipid components of bakery products

Effect of Different Egg Products on Lipid Oxidation of Biscuits

Egg products are one of the main ingredients used in bakery industries, and they contain cholesterol. Cholesterol suffers several chemical changes during the food processes, allowing some potentially toxic compounds called cholesterol oxidized products (COPs). Thus, the aim of this work was to study the evolution of lipid oxidation from eggs to egg products, and to evaluate the influence of egg products on COPs formation in biscuits formulated with them. The results confirmed that spray-drying technology improves the cholesterol oxidation 2.6 times compared to pasteurized eggs. Biscuit samples showed a COPs content that is strictly related to the egg products used. Samples formulated with spray-dried eggs noticed lower amounts of COPs compared to those formulated with pasteurized eggs. It is important to stress that COPs composition was different between the two samples, underlining that the kinetic of COPs formation is dependent on the type of egg products.

Plant sterols from foods in inflammation and risk of cardiovascular disease: a real threat?

High dietary intakes of cholesterol together with sedentary habits have been identified as major contributors to atherosclerosis. The latter has long been considered a cholesterol storage disease; however, today atherosclerosis is considered a more complex disease in which both innate and adaptive immune-inflammatory mechanisms as well as bacteria play a major role, in addition to interactions between the arterial wall and blood components. This scenario has promoted nutritional recommendations to enrich different type of foods with plant sterols (PS) because of their cholesterol-lowering effects. In addition to cholesterol, PS can also be oxidized during food processing or storage, and the oxidized derivatives, known as phytosterol oxidation products (POPs), can make an important contribution to the negative effects of both cholesterol and cholesterol oxidation oxides (COPs) in relation to inflammatory disease onset and the development of atherosclerosis. Most current research efforts have focused on COPs, and evaluations of the particular role and physiopathological implications of specific POPs have been only inferential. Appreciation of the inflammatory role described for both COPs and POPs derived from foods also provides additional reasons for safety studies after long-term consumption of PS. The balance and relevance for health of all these effects deserves further studies in humans. This review summarizes current knowledge about the presence of sterol oxidation products (SOPs) in foods and their potential role in inflammatory process and cardiovascular disease.

Sterol oxidation in ready-to-eat infant foods during storage

The effect of storage on sterol oxidation of ready-to-eat infant foods was evaluated. Two different liquid infant foods (honey or fruits flavors), prepared with milk and cereals, were stored for 0, 2, 4, 7 and 9 months at 25 degrees C. Sterol oxidation products (SOP) were isolated by cold saponification, purified by silica solid-phase extraction, and analyzed by gas chromatography (GC) and GC-mass spectrometry. beta-Sitosterol was the most representative sterol, followed by cholesterol and campesterol. No significant differences in the total and single SOP content (0.8-1 mg/kg of product) were observed with respect to storage time and type of sample; the main SOP found was 7-ketositosterol (<0.2 mg/kg of product). The extent of stigmasterol oxidation (2.9%) was higher than that of cholesterol (1.9%) and beta-sitosterol (1.4%). The type and quality of raw materials, as well as the processing conditions, seem to greatly influence SOP formation and accumulation in infant foods.

Monovarietal extra virgin olive oils: correlation between thermal properties and chemical composition

Thermal properties of monovarietal extra virgin olive oils were evaluated by means of differential scanning calorimetry (upon cooling) and related to their chemical composition (triacylglycerols, diacylglycerols, total and free fatty acids, oxidation status). The overall crystallization enthalpy did not significantly differ among samples and did not account for the differences observed in chemical compositions. On the contrary, a higher degree of unsaturation in the lipid profile induced a shift of the crystallization onset towards lower temperatures and narrowing of the crystallization temperature range. The presence of triacylglycerol lysis and lipid oxidation products shifted the crystallization towards higher temperatures and the phase transition developed over a larger temperature range. Differential scanning calorimetry thermograms were deconvoluted into three constituent exothermic peaks for all samples. The area of the two lower-temperature exotherms was found to be statistically correlated with the amount of triunsaturated and monosaturated triacylglycerols present in the oil. Thermal properties of extra virgin olive oil were found to be affected by oil chemical composition.

Improved postprandial response and feeling of satiety after consumption of low-calorie muffins with maltitol and high-amylose corn starch

The aim of this study was to determine the postprandial glucose (GR), insulin (IR), and triglyceride response as well as the satiety response (SR) to low-calorie muffins (LCMs) and to compare them to those of conventional plain muffins (PMs) and bread. The LCMs had a lower fat content, their sugar was replaced by maltitol, and wheat flour was partially replaced by high-amylose corn starch. We used bread as a reference to calculate glycemic (GI), insulinemic (II), and satiety indices (SI). Seven men and 7 women (33 +/- 7.8 y; body mass index = 25.8 +/- 2.9) were studied in a randomized crossover design and were given either bread, an LCM, or a PM during 3 different occasions. Plasma glucose, insulin, and triglyceride concentrations were periodically measured for 2 h after consumption. We used the same design in a separate assay to evaluate SR by means a subjective questionnaire. The results show that LCMs reduced the IR by 30% (P= 0.03) and lipemic response by 50% (P < 0.001) compared to PMs. GR was only found to be significantly different between bread and LCMs (52% lower in LCM; P= 0.03), with PMs in an intermediate position. The SR of LCMs is similar to bread and higher than PMs (191%; P= 0.02). We concluded that LCMs are a product with a very low GI with better postprandial and SRs than PMs. These metabolic properties are useful in normal and overweight persons. However, further research is needed on the effects of this type of products in individuals with impaired glucose tolerance.