Thais Lomônaco Teodoro da Silva

Determination of the bioactive compounds, antioxidant activity and chemical composition of Brazilian blackberry, red raspberry, strawberry, blueberry and sweet cherry fruits.

This study aimed to evaluate the chemical composition, identify the bioactive compounds and measure the antioxidant activity present in blackberry, red raspberry, strawberry, sweet cherry and blueberry fruits produced in the subtropical areas of Brazil and to verify that the chemical properties of these fruit are similar when compared to the temperate production zones. Compared with berries and cherries grown in temperate climates, the centesimal composition and physical chemical characteristics found in the Brazilian berries and cherries are in agreement with data from the literature. For the mineral composition, the analyzed fruits presented lower concentrations of P, K, Ca, Mg and Zn and higher levels of Fe. The values found for the bioactive compounds generally fit the ranges reported in the literature with minor differences. The greatest difference was found in relation to ascorbic acid, as all fruits analyzed showed levels well above those found in the literature.

Equivalence salting and temporal dominance of sensations analysis for different sodium chloride substitutes in cream cheese

The purpose of the study was to determine the potency and equivalence of salt substitutes (potassium chloride, magnesium chloride, monosodium glutamate, potassium lactate, calcium lactate and potassium phosphate monobasic) in cream cheese and to evaluate sensory flavour profiles. The methods used were magnitude estimation and temporal dominance of sensations (TDS). Equivalent salting of cream cheese containing 1% sodium chloride was obtained using: 1.2% potassium chloride, 2.56% monosodium glutamate, 2.5% magnesium chloride and 2.98% potassium phosphate. The TDS revealed that, other than salty taste, the most significant flavours produced were sour and bitter. The potencies of salt substitutes are much lower than that of sodium chloride.

Templating effects of dipalmitin on soft palm mid-fraction crystals

ABSTRACT The crystallization of lipids has important implications for the industrial processing of food products, such as chocolates, margarines, spreads, confectionery, as well as bakery and dairy products. Thus, blends of soft palm mid-fraction (PMF) and dipalmitin (PP) containing PP of 0.5 g/100 g and 1.0 g/100 g were investigated under stabilization time and conditions for controlling and improving the crystallization step of fat during fat modulation. Crystallization results showed by reducing the Avrami parameters tsfc, t1/2, and k, the addition of PP accelerated the crystallization process of PMF. Changes in the crystals morphology observed by polarized light microscopy gave a higher crystallized area and reduced crystals size in the microstructure of the PMF, which was also verified by the increase in melting point and solid fat content (SFC). The addition of PP caused changes in the arrangement of the PMF triacylglycerols (TAGs), by stabilizing the β´stable polymorphic form, thereafter stabilizing the melting profile and the consistency of PMF over time. These results have interesting implications in the fat and oil industry as they allow for the marketing of products with improved crystallization properties and the stabilization of more stable polymorphic forms, expanding the range of applications of slow-crystallizing fats.

Sucrose behenate as a crystallization enhancer for soft fats

The addition of sucrose behenate for the modification of the physical properties of soft fats, such as soybean oil-based interesterified fat, refined palm oil, and palm mid fraction was studied. The addition of sucrose behenate was verified to affect the crystalline network of fats, changing the hardness and solids profile. The isothermal crystallization behaviors of the fat blends with 1% sucrose behenate were analyzed at 20 and 25 °C. Temperature had a greater effect on the speed of crystallization (k) than the presence of the emulsifier. Sucrose behenate did, however, influence the crystallization mechanism, with changes observed in the Avrami exponent (n). These changes were also observed in the microstructure of the fats. Changes in the polymorphic behavior were observed with the addition of sucrose behenate, such as a possible delay in the α → β transition for interesterified fat, and the initial formation of the β polymorph in palm oil.

Structural characteristics of crystals formed in palm oil using sorbitan tristearate and sucrose stearate

ABSTRACT The formation and stabilization of fat crystals in palm oil (PO) by the templating effects of sorbitan tristearate (STS) and sucrose stearate (S-370) were examined. We observed that the crystallization mechanism occurred via heterogeneous nucleation, which was induced by co-crystallization or seeding, after the addition of STS or S-370, respectively. Overall, both emulsifiers, STS and S-370, caused an increase in the hardness of PO, which was related to changes in the microstructure. In addition, the intensity of this effect was shown to be dependent on the emulsifiers concentration. In differential scanning calorimetry analysis, S-370 proved to be associated predominantly to the crystallization of high-melting triacylglycerols (TAGs), while STS showed to actuate the crystallization of high and low-melting TAGs. Moreover, the addition of STS improved the polymorphic stability of the PO, while the use of S-370 resulted in a soft texture at lower temperatures.