Abstract: Based on available national standards, the level of phytosterols in cocoa milk should not exceed 3% of sterol compounds. The aim of this study is to control the quality of the product and evaluate the sterol composition application as an indicator of cocoa milk fat authentic. Therefore, the first part of the present study aimed to examine the sterol composition of ingredients, including milk, cocoa powders. For this purpose, the level of phytosterols in products determined. After the preparation of samples, their sterol composition examined using gas chromatography. Results showed that the level of cholesterol and phytosterols in milk was 99.24 and 0.76, respectively. The examination of the sterol profile of cocoa powder revealed that the largest portion of sterol compounds belongs to beta-sitosterol, stigmasterol and campesterol have the highest level among sterol compounds, respectively. In the second part of this study, the effect of adding various amounts (2, 5, and 8%) cocoa powders was examined on the level of phytosterols in milk due to determine the optimal amount of these compounds to observe standard ranges. As expected, by increasing the percentage of cocoa powders in the formulation of cocoa milk, the level of phytosterols increased.

Abstract Assessment of butter authenticity in combination with animal fat is a major challenge. Changing the butter composition can affect crystallization and polymorphism properties. The purpose of this study was to evaluate the thermal behavior of butter combined with (0-15% w/w) bovine tallow using Digital Calorimetric Scanning, and to determine fatty acid profile and isothermal microstructure in order to complete DSC data. According to the statistical analysis, obtained L_Pseudo equations show that in the crystallization curve, with increase of bovine tallow percentage in the butter, the onset temperature of peak 1 and amount of heat released in peak 2 increased and the onset temperature of peak 2 decreased and peak 1 became wider. In the melting curves, with increase of bovine tallow percentage, the onset temperature of peaks 1 and 2 increased. Regarding the value of R2, the onset temperature of peak 2 in the melting curve had capability of estimation 78%. The crystal morphology of butter samples was different and with increased temperature, larger crystals were observed. In general, scans of calorimetric results revealed that DSC is a valuable method for studying butter in combination with animal fat and also can be utilized for distinguishing pure fat from adulterated one.

Abstract Bleaching is an important part of the oil refining process, in which pigments, impurities, traces of metals, and oxidative-molecular components of oils are removed. In this regard, the optimization of bleaching conditions can be effective to increase oil quality. In this study, de-gummed and neutralized sunflower oil was bleached at 80, 90, 100, 110, and 120 °C for 15, 25, 35, 45, and 55 min by acid-activated bleaching clay with the concentrations of 0.4, 0.6, 0.8, 1, and 1.2% under laboratory conditions. At that point, peroxide, anisidine, plus Totox values, free fatty acid content, Rancimat, and specific UV absorption at 232 and 270 nm were analyzed via the RSM method. The model optimization using the RSM method revealed that the optimal conditions were 37.31 min, temperature 92.7 °C, and clay concentration 1.18%; this circumstance can meet 86.7% of the expectations as could be met for reducing the factors effective for oxidization during bleaching.

Egg yolk was partially replaced (0, 25, 50, 75, and 100%) with octenyl succinic anhydride (OSA)-modified potato starch in a reduced-fat mayonnaise formulation to curtail the problems associated with high cholesterol and induced allergic reactions. The physicochemical properties included parameters such as: pH, fat content, and emulsion stability of the formulations analyzed. The samples with 75% and 100% egg yolk substitute showed the maximum emulsion stability (>95% after two of months storage), and they were selected according to cholesterol content, particle size distributions, dynamic rheological properties, microstructure, and sensory characteristic. A significant reduction (84-97%) in the cholesterol content was observed in the selected samples. Particle size analysis showed that by increasing the amount of OSA starch, the oil droplets with the peak size of 70 µm engulfed by this compound became larger. The rheological tests elucidated that in the absence of egg yolk, OSA starch may not result in a final product with consistent texture and that the best ratio of the two emulsifiers (OSA starch/egg yolk) to produce stable reduced-fat, low cholesterol mayonnaise is 75/25. The microscopic images confirmed the formation of a stable cohesive layer of starch surrounding the oil droplets emulsified in the samples selected.