Jessica Fernanda Hoffmann

Starch digestibility and molecular weight distribution of proteins in rice grains subjected to heat-moisture treatment.

The objective of this study was to evaluate the effects of the heat-moisture treatment (HMT) applied to paddy rice grains on the physicochemical properties, in vitro starch digestibility, and molecular weight distribution of proteins in rice flour. The paddy rice grains were adjusted to 13%, 16%, and 18% moisture and autoclaved at 121°C for 30 and 60min. The HMT promoted a reduction of the amylose content, the swelling power, and the solubility of the rice flour. Changes in the relative crystallinity and molecular weight of the proteins extracted with a sodium phosphate buffer containing 2.0% sodium dodecyl sulfate (SDDS) were observed in HMT samples. The different methods for the quantification of resistant starch resulted in distinct resistant starch contents. The HMT (18%-60min) promoted an increase in resistant starch content and the HMT (16%-60min) caused an increase in the slowly digestible starch in the rice flour.

Bioactive and yield potential of jelly palms (Butia odorata Barb. Rodr.)

In this descriptive study, Butia odorata genotypes were evaluated for yield, fruit number, pulp yield, bioactive content (including phenolic compounds, carotenoid, anthocyanin, L-ascorbic acid, and fibre content), antioxidant potential, and phenotypic characteristics. Genotype 117 was the highest yielding, with an estimated fruit yield of 22,000 kg ha(-1) and pulp yield of 12,000 kg ha(-1). On the other hand, the lowest yielding genotype, accession 49, showed an estimated fruit yield of 8400 kg ha(-1). Jelly palm fruit were generally rich in phenolic content (280.50-398.50 mg 100(-1)g), carotenoid content (2.80-4.08 mg 100 g(-1)), and L-ascorbic acid content (34.63-63.84 mg 100g(-1)). While the highest yielding genotype was not the richest in bioactive content, the lowest yielding genotype showed the highest l-ascorbic acid content. Although fruit yield and phytochemical composition are desirable attributes in jelly palm fruit, none of the genotypes evaluated showed high levels of both. Therefore, fruit yield and bioactive phytochemical content appear to be inversely proportional.

Optimized Camellia sinensis var . sinensis , Ilex paraguariensis , and Aspalathus linearis blend presents high antioxidant and antiproliferative activities in a beverage model

A statistical optimization study was conducted to obtain a tea containing fermented rooibos (Aspalathus linearis), white tea (Camellia sinensis var. sinensis), and roasted mate (Ilex paraguariensis). An optimal combination of these species was proposed. This optimized tea inhibited 64% the lipoperoxidation in vitro and presented a high phenolic content, especially kaempferol, (+)-catechin, (-)-epicatechin, rutin, (-)-epigallocatechin, and (-)-epicatechin-2-O-gallate. Indeed, the antioxidant effect was confirmed by decreasing 30% the reactive oxygen species generation in human hepatoma carcinoma cells (HepG2, 100 and 240 µg/mL). In the cell viability assay, the GI50 for human colorectal adenocarcinoma epithelial cells (Caco-2) was about 547 µg/mL and 481 µg/mL for HepG2. The pasteurization process (65 °C/30 min) did not affect the total phenolic content and antioxidant activity of the optimized tea formulation. The sensory test indicated an acceptability index of 78%, showing that the analytical approach adopted was feasible to develop a phenolic-rich beverage.

Liquid Chromatography with mass spectrometry analysis of mycotoxins in food samples using silica hydride based stationary phases

Liquid chromatography with mass spectrometry analysis of selected food samples using silica hydride stationary phases allowed for the identification and quantification of common mycotoxins including aflatoxin B1, B2, G1, G2, ochratoxin A, and fumosinin B1. Phenyl and C18 columns showed relatively similar selectivity based on hydrophobicity but the phenyl phase provides an additional mechanism, π-π interaction. The most hydrophobic of the analyzed compounds was more strongly retained on the C18 column and also has fewer unsaturated sites, which limited the interaction with the phenyl phase. Bean, maize, rice, and wheat samples were harvested and stored under conditions conducive to fungal development, and all samples presented toxin contamination exceeding the maximum tolerable limits.

Stability of bioactive compounds in butiá (Butia odorata) fruit pulp and nectar

Butia odorata is a palm tree native to southern Brazil whose fruit (known as butiá) and leaves are used to make many food products and crafts. Butiá contain several biologically active compounds with potential health benefits. However, processing conditions can alter quality attributes including bioactive compound content. This study evaluated the stability of bioactive compounds in butiá pulp upon pasteurization, during 12months of frozen storage, and in butiá nectar after a 3-month storage period. Pulp pasteurization resulted in a reduction in phenolic, flavonoid, carotenoid, and ascorbic acid contents. After a 12-month frozen storage period, flavonoid, phenolic, and ascorbic acid contents decreased while carotenoid content remained unaltered. Carotenoid, ascorbic acid, and phenolic contents were unaffected by the 3-month storage of butiá nectar; however, flavonoid content and antioxidant potential were reduced. Despite bioactive compound degradation upon heat treatment and storage, butiá nectar remained rich in phenolics, especially (-)-epicatechin, rutin, and (+)-catechin.

Effects of moisture and temperature during grain storage on the functional properties and isoflavone profile of soy protein concentrate

The objective of this study was evaluate the effects of moisture and temperature during grain storage on the functional properties and isoflavone profile of soy protein concentrate. The protein concentrate was extracted from soybeans on the first day of storage and after 12months of storage, at 12 and 15% moisture and at temperatures of 11, 18, 25, and 32°C. The protein concentrate obtained from grains stored at 32°C showed decreased extraction yield (51.6% with 15% of moisture) and protein solubility (24.8% with 15% of moisture) with increased emulsifying capacity (52.2% with 12% of moisture) and foam formation, compared with sample obtained at the start of the storage period. The isoflavone profile showed a decrease in the concentrations of glycosylated, malonyl, and acetyl isoflavones and a corresponding increase in the concentrations of aglycone isoflavones, with the magnitude of these changes increasing with increasing storage temperature and moisture content.

Cooking quality properties and free and bound phenolics content of brown, black, and red rice grains stored at different temperatures for six months

The changes in cooking quality and phenolic composition of whole black and red rice grains stored during six months at different temperatures were evaluated. Brown rice with known cooking quality properties and low phenolic levels was used for purposes comparison. All rice genotypes were stored at 13% moisture content at temperatures of 16, 24, 32, and 40°C. Cooking time, hardness, free and bound phenolics, anthocyanins, proanthocyanidins, and free radical scavenging capacity were analysed. The traditional rice with brown pericarp exhibited an increase in cooking time and free phenolics content, while rice with black pericarp exhibited a reduction in cooking time after six months of storage at the highest studied temperature of 40°C. There as increases in ferulic acid levels occurred as a function of storage temperature. Red pericarp rice grains showed decreased antioxidant capacity against ABTS radical for the soluble phenolic fraction with increased time and storage temperature.

Polar Origanum vulgare (Lamiaceae) extracts with antifungal potential against Sporothrix brasiliensis

&NA; Oregano (Origanum vulgare) has anti‐Sporothrix spp. activity, including against strains that are resistant to antifungal drugs. As the studies are limited to the essential oil, the aim of this study was to evaluate the chemical, antioxidant and cytotoxic properties of polar oregano extracts and their anti‐Sporothrix brasiliensis activity. Aerial plant parts were used in the preparation of 10 min (INF10) and 60 min (INF60) infusions, a decoction (DEC) and a hydroalcoholic extract (HAE). Six phenolic acids and four flavonoids were identified and quantified through liquid‐chromatography (LC‐MS). Extracts in increasing order of total phenolic and flavonoid contents were HAE<INF60<INF10<DEC and HAE<DEC<INF60<INF10, respectively. All extracts showed DPPH and ABTS radical scavenging potential (HAE<INF60<DEC<INF10). HAE showed the least toxicity toward MDCK and CRFK cell lines in the MTT colorimetric assay. The antifungal potential against 29 S. brasiliensis isolates obtained from cats and dogs was evaluated following the CLSI M38‐A2 protocol adapted to natural products. Minimum inhibitory concentration for 50% of the isolates (MIC50) was 5 mg/ml for all extracts, and minimum fungicidal concentration for 50% of the isolates (MFC50) was 20 mg/ml for INF10 and 40 mg/ml for the remaining extracts. MIC90 was 10 mg/ml for all extracts, except for DEC (20 mg/ml). MFC90 was 40 mg/ml for INF10 and > 40 mg/ml for the other extracts. This is the first report of oregano extracts showing antifungal activity against S. brasiliensis. Its use in the treatment of sporotrichosis may be considered upon toxicity and safe‐use conditions are tested.

Hydrothermal treatment of maize: Changes in physical, chemical, and functional properties

The objective of this work was to assess the effects of a traditional parboiling treatment on physical, chemical and functional properties of yellow maize kernels. For this, maize kernels were subjected to the three main stages of a traditional parboiling process (soaking, steaming, and drying) at different moisture contents (15%, 25%, or 35%), and different pressure steaming times (0, 15, or 30 min). Kernels were evaluated for physical and chemical changes, while manually generated endosperm fractions were further evaluated for nutritional and functional changes. The parboiling process negatively altered the maize kernels properties by increasing the number of kernels with burst pericarp and decreasing the total carotenoid content in the endosperm by 42%. However, the most intense conditions (35% moisture and 30 min steam) lowered the number of broken kernels by 41%, and the number of stress cracks by 36%. Results also demonstrated that soaking enhanced the nutritional value of soaked yellow maize by increasing the thiamine content and the bound phenolic content in the endosperm fraction up to 102%. The proper implementation of this hydrothermal treatment could lead to significant enhancements in nutritional and functionality of maize products.

Quality of black beans as a function of long-term storage and moldy development: Chemical and functional properties of flour and isolated protein

The aim of this study was to evaluate the effects of moisture content and storage temperature on the percentage of moldy and fermented beans, mycotoxins levels, phenolic acids content, pasting properties of whole flour, as well as functional and thermal properties of protein isolates from black beans stored for 12 months. Beans stored under 14%/32 °C exhibited 16% of fermented grains, while at 17%/25 °C (42.3%) and 17%/32 °C (93.5%) of moldy plus fermented grains, named drastic conditions (DC). Mycotoxins were not present in grains from all storage conditions. Reduction of gallic, caffeic, and p-hydroxybenzoic acid contents, and increase of sinapic acid were observed in DC. Reduction of peak, final, and setback viscosities of bean flours in DC indicate the application in refrigerated and frozen products. The increase in foaming and reduction in foam degradation of the proteins highlights their use in beverages where the foam is an important factor.