Distribution of cholesterol in milk fat fractions

Reduction of Beta Cyclodextrin by Curd Washing in Low-Cholesterol Manchego Cheese

Beta-cyclodextrin (β-CD) is a cyclic oligosaccharide consisting of seven glucose units. β-CD is increasingly used in food research to reduce cholesterol due to its affinity for non-polar molecules such as cholesterol and as a natural additive. The purpose of this study was to evaluate the effect of curd washing in ewe's milk cheese on the reduction in cholesterol by β-CD from pasteurized ewe's milk Manchego cheese and the characteristics of its main components: milk, lipids, and flavor. An approximately 98.45% cholesterol reduction was observed in washed experimental cheeses that were treated by using β-CD. The remaining residual β-CD from the effect of curd washing was 0.15% in mature cheese, of the initial 1% β-CD treatment of the milk. The chemical properties (fat, moisture, and protein) did not change as a result of the curd washing with or without β-CD. The curd washing with or without β-CD on the levels of the various lipid fraction (fatty acids, triglycerides, and phospholipids) were comparable in treated and untreated cheeses. The effects of curd washing and the β-CD treatment did not significantly affect flavor components or short chain free fatty acids. The β-CD molecules were edible and nontoxic; as a result, they could be used safely in cholesterol removal processing in cheese manufacturing, improving the reduction in residual β-CD by curd washing by 85%. Therefore, the present study suggests that curd washing combined with β-CD is an effective process for cholesterol removal in Manchego cheese, preserving its desirable properties.

The Influence of β-Cyclodextrin on the Reduction of Cholesterol Content in Egg and Duck Liver Pâté

The use of β-cyclodextrin (β-CD) to reduce cholesterol is increasing in food research due to its affinity for non-polar molecules such as cholesterol. The objective of this study was to study the ability of β-CD to remove cholesterol in natural egg, powdered egg, and duck liver pâté and its effect on individual fatty acids. A concentration of 5% of β-CD was found to be a suitable amount to remove 80.04 ± 4.96–82.12 ± 5.36% of cholesterol from yolk and powdered eggs and 80.21 ± 5.28% of cholesterol from duck liver pâté. β-CD complexed to cholesterol was precipitated and removed by centrifugation. Individual fatty acid compositions did not differ (p < 0.05) between the controls and the products treated with 5% β-CD.

Effect of Beta Cyclodextrin on the Reduction of Cholesterol in Ewe's Milk Manchego Cheese

Beta-cyclodextrin (β-CD) is a cyclic oligosaccharide consisting of seven glucose units and is produced from starch using cyclodextrin glycotransferase enzymes to break the polysaccharide chain and forming a cyclic polysaccharide molecule. The use of β-CD in food research for reduction of cholesterol is increasing due to its affinity for non-polar molecules such as cholesterol. The aim of this study was to evaluate the feasibility of using β-CD in cholesterol removal from pasteurized ewe’s milk Manchego cheese and evaluate the effect on the main components of the milk, lipids, and flavor characteristics. Approximately 97.6% cholesterol reduction was observed in the cheese that was treated using β-CD. Physicochemical properties (fat, moisture and protein) were not changed by the β-CD treatment, except the soluble nitrogen and non-protein nitrogen that showed slight differences after the treatment. The amount of the different components of the lipid fraction (fatty acids, triglycerides and phospholipids) were similar in cheeses treated and not treated with β-CD. Flavor compound and short chain free fatty acids were not mostly significantly influenced by the effect of the β-CD. β-CD molecules are edible and nontoxic and as a result they can be used safely for cholesterol removal processing in cheese manufacturing. Therefore, the present study suggests that β-CD treatment is an effective process for cholesterol removal from Manchego cheese while preserving its properties.

Sensory quality of milk fat with low cholesterol content fractioned by molecular distillation

BACKGROUND

Anhydrous milk fat (AMF) is a valuable ingredient in several industries, but its cholesterol content is a disadvantage because it is associated with several diseases. The objective of this study was to remove the largest possible amount of cholesterol from AMF by molecular distillation and to analyze the sensory properties of the obtained product. AMF was subjected to various molecular distillation arrangements.

RESULTS

The first set of experiments involved molecular distillations performed over a range of evaporation temperatures. Then, according to the outcome of the first set of experiments, a second set of experiments was carried out in order to study the effect of the feeding flow rate. Finally, the number of distillation stages was modified.

CONCLUSION

The best results were obtained in a three-stage arrangement, in which ∼60% of cholesterol was removed with a 30.48% distillate yield. The sensory properties of this distillation cut were also the most similar to those of the untreated milk fat. © 2018 Society of Chemical Industry.

Optimization of process parameters for supercritical fluid extraction of cholesterol from whole milk powder using ethanol as co-solvent

BACKGROUND

In spite of being highly nutritious, the consumption of milk is hindered because of its high cholesterol content, which is responsible for numerous cardiac diseases. Supercritical carbon dioxide using ethanol as co-solvent was employed to extract cholesterol from whole milk powder (WMP). This study was undertaken to optimize the process parameters of supercritical fluid extraction (SCFE), viz. extraction temperature, pressure and volume of ethanol.

RESULTS

The cholesterol content of WMP was quantified using high-performance liquid chromatography. The impact of the extraction conditions on the fat content (FC), solubility index (SI) and lightness (L*) of the SCFE-treated WMP were also investigated. The process parameters were optimized using response surface methodology. About 46% reduction in cholesterol was achieved at the optimized conditions of 48 °C, 17 MPa and 31 mL co-solvent; flow rate of expanded CO₂ , static time and dynamic time of extraction were 6 L min^-1 , 10 min and 80 min respectively. The treated WMP retained its FC, SI, and L* at moderate limits of 183.67 g kg^-1 , 96.3% and 96.90, respectively.

CONCLUSION

This study demonstrated the feasibility of ethanol-modified SCFE of cholesterol from WMP with negligible changes in its physicochemical properties. © 2016 Society of Chemical Industry.

Revisión: Aplicación de las técnicas cromatográficas al estudio de triglicéridos y esteroles de la grasa de leche / Review: Application of chromatographic techniques to the study of triglycerides and sterols of milk fat

The latest developments in analytical techniques, mainly chromatographic, for the study of triglycer ides (TG) and sterols in milk fat are revised. Gas chromatography (GC) with packed or short capillary columns has been used to separate TG according to their carbon numbers (CN) and can be applied to the detection of foreign fats in milk fat. Combined or hyphenated chromatographic techniques are indispensable in order to identify and quantify individual molecular species of TG: thin layer chro matography (TLC) or high performance liquid chromatography (HPLC) with Ag+ as prefraction stage, followed by supercritical fluid chromatography, GC with long capillary column, and HPLC with reverse phase and mass spectrometry as detector. These techniques, along with non-specific and/or specific hydrolysis procedures, have allowed a better knowledge of the positional distribution of the fatty acids within the molecules of TG. Concerning the study of the esterol fraction, the supression of the stages of fat extraction—separation of the insaponifiable and derivatization—previous to the analy sis by GC represents a considerable advance that should be in part attributed to the improvement of the chromatographic techniques.

Cholesterol extraction from ghee using glass beads functionalized with beta cyclodextrin

Beta-cyclodextrin (β-CD) was covalently immobilized on glass surface. Functionalized glass surface was characterized by X-ray photoelectron spectroscopy (XPS) and elemental analysis. Glass surface functionalized with β-CD was used to remove cholesterol from ghee (clarified butter fat). 78.8 % cholesterol was reduced in 2 h at 25 °C and 170 rpm. Same surface was used repeatedly for 10 cycles and no reduction in cholesterol removal efficiency was observed. Modified glass surface showed almost no degradation in repeated use in cholesterol reduction experiments.

Modified milk fat reduces plasma triacylglycerol concentrations in normolipidemic men compared with regular milk fat and nonhydrogenated margarine

BACKGROUND

A modified milk fat with reduced cholesterol was developed by fractionation technology.

OBJECTIVE

The effect of this modified milk fat on the lipoprotein profile of 21 normolipidemic men was compared with that of regular milk fat and nonhydrogenated margarine.

DESIGN

A crossover design was used for the administration of the 3 experimental diets, which provided 13240 kJ as 16% protein, 51% carbohydrates, 33-34% lipids, and 21 g fiber/d. The ratio of polyunsaturated to saturated fat was 1.3:1 for the margarine diet and 0.3:1 for the milk-fat diets. The cholesterol content of the modified milk-fat and margarine diets was similar (248 and 254 mg/d, respectively), but was significantly higher (428 mg/d) for the regular milk-fat diet.

RESULTS

Modified and regular milk fats did not change plasma total and LDL cholesterol significantly, but margarine did (P < 0.01). Furthermore, modified milk fat maintained initial HDL(2)-cholesterol concentrations, but margarine reduced this variable significantly (P < 0.05). These results can be explained by the lower ratio of polyunsaturated to saturated fat in the modified and regular milk-fat diets than in the margarine diet. Men who ingested modified milk fat had significantly (P < 0.05) lower total and VLDL-triacylglycerol and VLDL-cholesterol concentrations than did those who ingested either regular milk fat or margarine. This may have been, in part, because of the lower intestinal fat absorption with modified milk fat than with regular milk fat and margarine arising from changes in the melting properties of milk fat with fractionation.

CONCLUSION

A reduction in plasma triacylglycerol concentrations after the consumption of modified milk fat may prevent the onset of hypertriacylglycerolemia.

Extraction of ewe's milk cream with supercritical carbon dioxide

The extraction of ewe's milk cream by supercritical carbon dioxide in the pressure range 9-30 MPa (90-300 bar) and at temperatures of 40 degrees C and 50 degrees C was studied. The solubility of total fat increased with pressure at both temperatures until a plateau was reached. The extraction of cholesterol also increased with pressure until a plateau was reached and it was higher at 50 degrees C than at 40 degrees C when the pressure was > or = 15 MPa (150 bar). The triglyceride composition of each extract, determined by GC, showed that extracts obtained at lower pressures were enriched in short-chain triglycerides and their concentration decreased as the pressure increased. In the other hand, long-chain triglycerides were enriched in the extracts obtained at higher pressures and their concentration rose with increasing pressure.