Ana Augusta Odorissi Xavier

Caracterização físico-química de polpas de frutos da Amazônia e sua correlação com a atividade anti-radical livre

Physical and chemical characteristics (color, pH, titratable acidity, total soluble solids, lipid content, moisture) and levels of bioactive compounds (ascorbic acid, total phenolics) were determined in fifteen samples of fruit pulps from Amazonia (abiu, acerola, acai, araca-boi, bacaba, bacuri, buriti, caja, cajarana, caju, cupuacu, graviola, murici, noni e tamarindo). The free radical scavenger activity was evaluated by the ABTS assay. Some pulps presented high antioxidant potential, associated with the free radical scavenger activity measured and the content of bioactive components, such as phenolic compounds and ascorbic acid, especialy in acerola and acai. The total phenolic content was correlated to antioxidant capacity of pulps.

Oxidative stability of yogurt with added lutein dye

This study evaluated the effect of adding lutein dye on the oxidative stability of yogurt during 35 d of refrigerated storage, in the presence and absence of light. Yogurts manufactured without and with the equivalent of 1.5mg of lutein in 120 g of the final product were characterized for their total carotenoid and riboflavin contents, and the behaviors of both riboflavin and lutein were monitored during storage. A decrease in riboflavin content occurred, with concurrent appearance of its derived-oxidation products in the yogurts without added lutein and exposed to light during storage. The yogurts with added lutein dye showed constant lutein and riboflavin contents throughout storage both for the samples stored under light and for those stored in the dark. Yogurts (120 g) with the addition of 0.5, 1.5, and 2.5mg of lutein dye were evaluated for their sensory acceptance, and the statistical analysis showed no differences between the samples for the attributes of aroma and flavor. These results indicate that the added lutein remained stable throughout the storage period and conferred protection for the riboflavin against photooxidation, preserving the quality of the yogurts.

Transference of lutein during cheese making, color stability, and sensory acceptance of Prato cheese.

The consumption of lutein is associated with the prevention and reduction of age-related macular degeneration. Its incorporation into Prato cheese as a yellowish food coloring is a valid alternative to increase the daily intake of this compound. However, part of the lutein added may be lost in the whey during the cheese making, or it can be degraded by light during storage, resulting in color changes reducing the sensory acceptance of the cheese. The objectives of this study were to determine the transference of the lutein (dye), added to the milk, in the whey, and cheese, to evaluate the effect of the lutein addition, light exposure, and storage time on the cheese color, and to verify the sensory acceptance of Prato cheese with addition of lutein. The lutein recovery of cheese was 95.25%. Color saturation (chrome) increased during storage time resulting in a cheese with more intense color, but there were no changes in the hue of the cheese. Adjusting the amount of lutein added to Prato cheese may lead to greater acceptance. The high recovery of lutein in the cheese and the fact that the hue remained unchanged during storage under light showed that the incorporation of lutein into Prato cheese is feasible from a technical point of view.

Xanthophyll esters are found in human colostrum

SCOPE Carotenoids in human milk are associated with other lipid counterparts in several metabolic processes. One interesting association that has not been demonstrated to date is the presence of xanthophyll esters. Colostrum and mature milk samples were analyzed to determine the occurrence of xanthophyll esters and identify the compounds. Thus, the association of the amounts of these compounds with lactation and whether they are significant contributors to the carotenoid profile of human milk was assessed. METHODS AND RESULTS Pre-term and term delivering mothers were included in the study to donate colostrum at 3-5 days postpartum and mature milk at 15 days postpartum. Carotenoids extracts were subjected to a clean-up procedure to remove the triacylglycerol fraction and then analyzed by HPLC-MSn . Identification of xanthophyll esters was achieved by considering their chromatographic behaviour, UV-visible characteristics and MSn features. CONCLUSION Xanthophyll esters are significant contributors to the carotenoid profile in the colostrum, while mature milk does not contain these compounds. Therefore, fatty acid acylation to xanthophylls is activated during the accumulation of carotenoids in the human mammary gland. The sharp decline in the amount of xanthophyll esters in mature milk indicates that the lipophilic components are those recently incorporated in the mammary epithelium.

Desenvolvimento e validação de método espectrofotométrico para determinação de corante à base de luteína adicionado em iogurte desnatado

A simple analytical method for extraction and quantification of lutein colorant added to yogurt was developed and validated. The method allowed complete extraction of carotenoids using tetrahydrofuran in vortex, followed by centrifugation, partition to diethyl ether/petroleum ether, and drying. The carotenoids dissolved in ethanol were quantified by UV-Vis spectrophotometry. This method showed linearity in the range tested (1.41-13.42 µg g-1), limits of detection and quantification of 0.42 and 1.28 µg g-1, respectively, low relative standard deviation (3.4%) and recovery ranging from 95 to 103%. The method proved reliable for quantification of lutein added to yogurt.

Carotenoids as a Source of Antioxidants in the Diet

Carotenoids, widely distributed fat-soluble pigments, are responsible for the attractive colorations of several fruits and vegetables commonly present in our daily diet. They are particularly abundant in yellow-orange fruits (carrots, tomatoes, pumpkins, peppers, among others) and, although masked by chlorophylls, in dark green leafy vegetables. Several health benefits have been attributed to carotenoids or to foods rich in these pigments, by means of different mechanisms-of-action, including the role as provitamin A of almost 50 different carotenoids and the antioxidant activity that protects cells and tissues from damage of free radicals and singlet oxygen, providing enhancement of the immune function, protection from sunburn reactions and delaying the onset of certain types of cancer. Common food sources and the efficiency of the absorption of carotenoids, analytical approaches used for measurement of their antioxidant effect and an overview of some epidemiological studies that have been performed to assess the beneficial impact of carotenoids in human health are outlined in this chapter.

Efeito do congelamento e da liofilização sobre a bioacessibilidade in vitro dos carotenoides de manga (Mangifera indica L. cv. Haden)

Resumo O congelamento e a liofilização são práticas comuns na rotina de laboratório para a conservação de amostras perecíveis como frutas e vegetais. Entretanto, sabe-se que o processamento de alimentos pode afetar a bioacessibilidade dos carotenoides presentes nos alimentos. Neste trabalho o efeito do congelamento e da liofilização sobre a bioacessibilidade in vitro dos carotenoides de manga cv. Haden foi avaliado. Os resultados demonstraram que o congelamento e armazenamento da manga a -37 °C não alterou os níveis de bioacessibilidade dos carotenoides da fruta mesmo após 180 dias de armazenamento, demonstrando ser um método adequado para conservação destas amostras previamente às análises de bioacessibilidade in vitro.