Studies of chemical and enzymatic characteristics of Yacon (Smallanthus sonchifolius) and its flours

Due to the importance of studies on yacon related to health, its in natura pulp, in natura peel, pulp flour, and peel flour were chemically analyzed in terms of its centesimal composition, specific minerals, total dietary fiber and fractions, pH, total soluble solids, total titratable acidity, tannins, oxalic acid, and nitrate. The polyphenoloxidase and peroxidase enzymatic activities were evaluated for in natura pulp and peel only. Yacon pulp and peel flour presented average yield of 7.94% and 10.86%, respectively. The in natura pulp presented a higher moisture and carboydrate content and lower lipid, protein, total dietary fiber, and ash than those of the peel flour. The same pattern was observed for pulp flour when compared to peel flour. The highest tannin, nitrate, and oxalic acid levels were found in the peel flour, 15,304.5 mg.kg-1, 1,578.3 mg.kg-1, and 7,925.0 mg.kg-1 (wet weight), respectively. The polyphenoloxidase and peroxidase enzymes presented higher enzymatic activity in the yacon peel. Based on the results obtained, it can be said that the yacon and its derivatives are important dietary carbohydrate and mineral sources and contain antinutritional substance contents lower than those harmful to health.

Phenolic compounds in Merlot wines from two wine regions of Rio Grande do Sul, Brazil

In Brazil, the grape and wine production takes place mainly in the state of Rio Grande do Sul, and the region "Serra" is known as the traditional wine region. In the last years, new areas have emerged, with emphasis for the Campanha region; the red wines from this region have low acidity, little color intensity, and are wines to drink while young, even when produced from grape varieties such as Merlot and Cabernet Sauvignon. The objective of this study was to evaluate the influence of different maceration types on the phenolic compounds of Merlot wines made with grapes produced in two regions of Rio Grande do Sul, Serra and Campanha, as well as to identify the key differences between the wines produced. The localization of the vineyards seems to have more influence on the wine characteristics than the maceration type. The color due copigmentation was an important aspect in the wines made with short maceration. The effect of extended maceration was different than the expected for the Campanha region wines; the extended maceration increased the extraction of tannins resulting in greater color intensity and a greater amount of anthocyanins. The pH control seems to be a key factor for the Campanha region wines.

Effect of soaking on the nutritional quality of pequi (Caryocar brasiliense Camb.) peel flour

Pequi peel comprises 76% of the whole fruit and it is discarded during consumption. Thus, pequi peel has been considered a solid residue, although it has potential for use in various applications. Limitations in the use of this material are mainly due to the lack of information of its nutritional composition, especially about the toxic or antinutritional factors. Soaking is often used to prepare complementary foods and has been reported to be beneficial for enhancing nutritive value. The effect of soaking on the nutritional quality of pequi peel flour was determined by measuring changes in chemical composition, antinutritional factors, total phenols and in vitro protein and starch digestibility. The results showed that 24 h of maceration increases the content of lipids (200%), protein (28.3%) and dietary fibber (31%), while carbohydrate and ash content decreases. There were no haemagglutination activity or α-amylase inhibitors, but it was detected the presence of phytic acid (0.4 g 100 g-1). The soaking reduced 8.5% phenols and 19.0% tannins, 6.2% protein digestibility, and was also effective to eliminate trypsin inhibitors, and increase starch digestibility (24.2%). Soaking was efficient to improve nutritional characteristics of the pequi peel flour, opening up possibilities for its use in food formulations.

Sensory and physico-chemical characteristics of desserts prepared with egg products processed by freeze and spray drying

In this work, three freeze-dried (FD) egg products (whole egg (WE), egg yolk (EY) and egg white (EW)) were obtained and the acceptability of confections prepared with each was evaluated. Sensory analyses for confections were performed by hedonic testing with fifty panelists in each evaluation. The studied confections were: Condensed Milk Pudding (P), Quindim (Q) and Meringue (M). The results obtained for confections made with FD egg products were compared with the achieved through other formulations of the same desserts made with fresh (F) or spray-dried (SD) egg products. The sensory analysis results for confections made with FD egg products showed good acceptance by panelists. A principal component analysis of the sensory evaluation data was carried out to identify similarities between the different egg products. The PCA supported the conclusion that FD egg products can substitute their fresh and SD counterparts in dessert formulations with good acceptability while keeping the advantages conferred by the freeze-drying method.

Effect of postharvest temperature on the shelf life of gabiroba fruit (Campomanesia pubescens)

The objective of this study was to determine the optimal temperature for storing gabiroba fruit (Campomanesia pubescens) without affecting compounds' quality. The fruits were stored at different temperatures (0 ºC, 6 ºC, 12 ºC, and 20 ºC) and the effect on the pH, total titratable acidity, soluble solids, total sugars, vitamin C, and antioxidant components such as tannins and total phenolic compounds was evaluated. It was observed an increase in the pH and total titratable acidity during storage at all the temperatures tested. Gabiroba fruits were stored for 9 and 3 days at 12 ºC and 20 ºC, respectively, and under both temperatures they showed a reduction in tannins and an increase in vitamin C content. As gabirobas armazenadas a 0º and 6 ºC alcançaram maior tempo de armazenamento After 12 days of storage, the fruits stored at 6 ºC contained higher amounts of water soluble solids, sugars, and antioxidants. In general, for long term storage, it is suggested to store gabiroba fruits at 6 ºC. On the other hand, for short term storage, the temperature of 12 ºC would be the better to keep high levels of vitamin C and phenolic compounds.

Evaluation of iron bioavailability in a mixture of cereals, seeds, and grains ("Human Ration")

Iron bioavailability was evaluated in three mixtures of cereals, seeds, and grains ("Human Ration"): light, regular, and homemade provided to rats. The animals received an iron depletion diet for 21 days, followed by a repletion diet containing 12 mg·kg-1 of iron for 14 days. The hemoglobin regeneration efficiency and the relative biological value did not differ between the light mixture and control group. The iron bioavailability of the light mixture of cereals, seeds, and grains and the control group were 99.99±27.62 and 80.02±36.63, respectively, while the regular and homemade mixtures of cereals, seeds, and grains showed lower iron bioavailability, 50.12±35.53 and 66.66±15.44, respectively; the iron content of the diet with light cereal mixture light was statistically similar to that of the control (ferrous sulfate 99.99±27.62). The high content of tannin (202.81±19.53 mg·100-1) in the diet with the regular cereal mixture may have contributed to its low iron bioavailability. The higher intake of soluble fiber by the animals fed the light mixture (21.15±0.92 g) was moderately correlated (r=0.5712, p=0.0018) with the concentration of propionate in the caecal bulk (65.49±11.08 µmol/g). The short chain fatty acids produced by soluble fiber fermentation, associated with the low-content of tannin may have improved iron solubility and absorption in the light cereal mixture diet. The iron bioavailability in the light mixture of cereals, seeds, and grains was similar to that of ferrous sulfate.

Cytotoxic and genotoxic potential of liquid synthetic food flavorings evaluated alone and in combination

This study aimed to evaluate the cytotoxic and genotoxic potential of food flavorings (Strawberry, Condensed Milk and Chocolate) on Allium cepa meristematic root cells, with exposure times of 24 and 48 hours. Cytotoxic and mutagenic potential were evaluated separately at doses of 0.2, 0.4 and 0.6 ml and in combination, in which for each dose, the same dose of one other flavoring was combined. The results were analyzed by the Chi-square test (p <0.05). The Strawberry flavor in both exposure times and the three studied doses, the Condensed Milk at 0.6 ml in the 48 hour exposure time, the Chocolate flavor at 0.4 ml, exposure time of 48 hours, and at 0.6 ml, in both exposure times and all treatments with combined doses, significantly reduced the cell division rate, proving to be cytotoxic. No treatment resulted in a significant number of cellular aberrations in A. cepa cells, therefore, the flavorings, under the conditions studied, were non- mutagenic.

In vitro and in vivo antioxidant activity of the pulp of Jatobá-do-cerrado

Abstract Oxygen metabolism in cells causes the production of free radicals, which produce damage, including changes in cell structure and function. Antioxidants are substances that, at low concentrations, slow down or prevent oxidation. Fruits and vegetables contribute to the dietary supply of these compounds. The flora of the Cerrado in Brazil has shown to have high levels of bioactive compounds. This study aimed to characterize the antioxidant activity of the pulp of jatobá-do-cerrado in vitro and in vivo.In vitro antioxidant activity of the aqueous, ethanol and aqueous acetone extracts was evaluated by the DPPH method. We determined total phenols by the Folin-Ciocalteu assay and tannins by the Folin-Denis method.In vivo antioxidant potential of the aqueous acetone extract was evaluated by the TBARS technique. The aqueous acetone extract had the highest antioxidant capacity, followed by the aqueous and ethanol extracts. The same pattern occurred in the extraction of phenols and in the extraction of tannins. In vivo administration of the aqueous acetone extract inhibited lipid peroxidation compared to the control group. The inhibition of peroxidation has increased by elevating the dosage concentration of the extracts, demonstrating a significant antioxidant potential in vivo as well as in vitro.