Dietary Polyphenols: What is the Estimated Intake in Population Studies With Adults and Elderly People?

Estimates of dietary intake of polyphenols have been limited to specific samples from certain population groups, and different databases have been used to quantify the levels of these compounds, which makes it difficult to compare results. PURPOSE OF REVIEW: This review collated estimates of polyphenol intake from population studies including adults and elderly from different parts of the world by using a single database: Phenol-Explorer. RECENT FINDINGS: Through seven population-based studies performed in five different countries, it was possible to identify that Brazil was the country with the lowest intake of polyphenols, whereas Poland had the highest dietary intake. The most ingested subclasses of polyphenols in different countries were phenolic acids and flavonoids, and non-alcoholic beverages (coffee, tea, and orange juice) were the foods that most contributed to the intake of polyphenols. Despite the attempt to standardize this study to obtain worldwide intake estimates that could be comparable, gaps were found regarding the assessment of food consumption, standardization to obtain the polyphenol content of foods in Phenol-Explorer, calculation in aglycone equivalents, and caloric adjustment of the estimates. There is a need for more studies on the dietary polyphenols intake of representative samples of populations from different countries to collate more data on the quantities consumed and the main contributing foods.

Yerba Mate (Ilex paraguariensis) Processing and Extraction: Retention of Bioactive Compounds

Ilex paraguariensis is a native tree from South America known for the presence of bioactive compounds, and its processed leaves are consumed as hot and cold infusions. After harvest (step 1), the leaves are subjected to flame blanching to inactive the enzymes (step 2), followed by drying and milling (step 3). The impacts of I. paraguariensis processing on leaf composition were investigated by extracting the major compounds (chlorogenic and isochlorogenic acids (3-CQA, 4-CQA, 5-CQA, 3,4-DQA, 3,5-DQA and 4,5-DQA), p-coumaric acid, caffeine and rutin) using different ratios of ethanol and water as extraction solvent (EW 25:75, 50:50, and 75:25 (w/w)). The solvent ratio of EW 50:50 was more effective in extracting the chlorogenic acids isomers, with retention of chlorogenic acids of 3463, 9485, and 9516 µg mL- 1 for steps 1, 2, and 3, respectively. Rutin and p-coumaric acid exhibited similar behavior with the increment of processing steps; however, p-coumaric acid was only detected in steps 2 and 3 for the solvent ratios EW 50:50 and 25:50. The caffeine extraction from I. paraguariensis varied from 936 to 1170 µg mL- 1 for all processing steps, with emphasis on its concentration extracted in step 1. The evolution of processing steps led to a higher retention of phenolic compounds from I. paraguariensis, which was not observed when using different solvent ratios, and the solvent ratio EW 50:50 was more effective for the extraction of chlorogenic acids. The successful extraction of chlorogenic acids from I. paraguariensis in this study proved to be a promising alternative for the use of yerba mate beyond the cuia cup.

Red araçá pulp microencapsulation by hydrolyzed pinhão starch, and tara and arabic gums

BACKGROUND

Red araçá is a Brazilian native species whose fruits are rich in phenolic acids, flavonoids, anthocyanins, and carotenoids. To preserve the properties of compounds during processing, red araçá pulp (RAP) was encapsulated by hydrolyzed pinhão starch (PS), tara gum (TG), and arabic gum (AG) in different blends in equal proportions, serving as a coating material.

RESULTS

Fresh RAP had a gallic acid equivalent of 3098 mg per 100 g of dry weight, 156.29 μg β-carotene per gram of dry weight, total anthocyanins of 18 mg per 100 g of dry weight and exhibited high antioxidant activity. The highest encapsulation efficiency achieved with the PS, TG, and AG blend was 80.4% for the total carotenoids, and that for the total anthocyanins was 76% with the TG and AG blend. Only one step of antioxidant activity degradation was identified, and the carrier system PSTG was efficient at maintaining the antioxidant activity, with half-life of 23.60-37.27 days.

CONCLUSION

The use of PS alone as a coating material or associated with TG and AG gums resulted in improved retention of bioactive compounds, these being an excellent alternative coating material since they improved the stability of the antioxidant activity of RAP. © 2020 Society of Chemical Industry.

Carioca bean starch upon synergic modification: characteristics and films properties

BACKGROUND

The use of damaged beans for starch isolation comprises an end-use alternative for a product that is not accepted by the consumer. For that reason, isolation and modification of Carioca bean starch should be explored and evaluated as a suitable source for biodegradable material. The present study aimed to evaluate the synergism of physical and chemical modifications on Carioca bean starch with respect to improving the properties of biodegradable films. A heat-moisture treatment (HMT) followed by oxidation by sodium hypochlorite was performed and vice versa.

RESULTS

Synergism was noted in the starch properties compared to the single modification. When the oxidation was applied first, a higher amylose and carbonyl content was noted. HMT, isolated and as a second modification, caused a more pronounced effect on viscosity profile than the oxidized starch, with an increase in paste temperature and a decrease in viscosity, breakdown and final viscosity.

CONCLUSION

The results obtained in the present study reflect a decrease in water vapor permeability, although a higher tensile strength was noted when oxidation was applied, as a single and as a first modification. © 2020 Society of Chemical Industry.

Innovative process for obtaining modified nanocellulose from soybean straw

In the present research, soybean straw was used to prepare nanocellulose (NC) via a ball mill, in different milling times (6, 9, and 12 h) and in-situ modified with an anionic surfactant. NCs were characterized for their chemical structure, surface composition, dimension and stability, morphology, crystalline structure, and thermal stability. Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy results indicated a cellulosic structure for NCs and a physical interaction due to the electronic attractions between nanocellulose hydroxyls and surfactant end chain groups. The dynamic light scattering, Zeta potential, and transmission electron microscopy indicated that the in situ modified samples showed smaller sizes and good electrostatic stability. Besides, while ball mill resulted in nanofibers, the in situ modified-NC showed a nanocrystal shape, indicating that the surfactant alters the milling process and cellulose scale reduction. The modified-NC showed lower crystallinity and crystal size than unmodified nanocelluloses due to the surfactant chains' addition and influence during the milling process. The modified-NC showed slightly superior thermal stability. The NC-12S showed smaller particle sizes, high electrostatic, and thermal stability and indicated that 12 h is adequate to prepare modified nanocellulose via in situ modification. The prepared samples could be potentially used as coatings, emulsifiers, and nanocomposites reinforcing agents.

Antimicrobial electrospun ultrafine fibers from zein containing eucalyptus essential oil/cyclodextrin inclusion complex

The aim of this study was to produce ultrafine fibers from zein incorporated with a complex of eucalyptus essential oil (EEO) and β-cyclodextrin (β-CD) with antimicrobial properties by electrospinning technique. The EEO was characterized by chemical composition and antimicrobial tests against three Gram positive and four Gram negative bacteria. The inclusion complex (IC) was prepared with β-CD and EEO by co-precipitation technique and added at different concentrations in zein polymer solution using aqueous ethanol as solvent. The morphology, thermal properties, functional groups, and antimicrobial activity against L. monocytogenes and S. aureus of the ultrafine fibers were evaluated. The composite membranes containing 24% IC exhibited a greater reduction of growth as compared to the fibers without addition of IC. For L. monocytogenes the growth reduction was 28.5% and for S. aureus it was 24.3%. The electrospun IC-β-CD/EEO composite membranes are promising for use in antimicrobial applications, such as food packaging.

Films based on protein isolated from croaker (Micropogonias furnieri) and palm oil

BACKGROUND

The microstructure and the physical, mechanical, barrier and thermal properties of films based on different concentrations of protein isolated from croaker waste (CPI) and palm oil (PO) were analyzed. Films were elaborated by a casting technique using 2, 3 and 4 g CPI 100 g(-1) of a filmogenic solution and 0, 10 and 20 g of PO 100 g(-1) CPI.

RESULT

Microstructure of the film surfaces of CPI with PO showed no presence of lipid droplets dispersed in the filmogenic matrix, although a rough surface was present. Films with 3% and 4% CPI and 20% PO had the lowest rates of water vapor permeability. When there was an addition of PO to the reduced tensile strength of the films, regardless of the concentration of CPI, this addition reduced the elongation of films with 3% and 4% CPI; however, it did not influence films with 2% CPI, which did not differ from the control film (0% OP). Thermal analysis revealed that films with the highest PO percentage had a lower initial weight loss when compared with other films, due to higher hydrophobicity.

CONCLUSION

The use of protein isolate obtained from fish residues of low commercial value and palm oil is viable for the production of biodegradable films because the latter constitute good barrier properties and thermal stability. © 2015 Society of Chemical Industry.

Films based on oxidized starch and cellulose from barley

Starch and cellulose fibers were isolated from grains and the husk from barley, respectively. Biodegradable films of native starch or oxidized starches and glycerol with different concentrations of cellulose fibers (0%, 10% and 20%) were prepared. The films were characterized by morphological, mechanical, barrier, and thermal properties. Cellulose fibers isolated from the barley husk were obtained with 75% purity and high crystallinity. The morphology of the films of the oxidized starches, regardless of the fiber addition, was more homogeneous as compared to the film of the native starch. The addition of cellulose fibers in the films increased the tensile strength and decreased elongation. The water vapor permeability of the film of oxidized starch with 20% of cellulose fibers was lower than the without fibers. However the films with cellulose fibers had the highest decomposition with the initial temperature and thermal stability. The oxidized starch and cellulose fibers from barley have a good potential for use in packaging. The addition of cellulose fibers in starch films can contribute to the development of films more resistant that can be applied in food systems to maintain its integrity.

Polishing and parboiling effect on the nutritional and technological properties of pigmented rice

This study aims to evaluate the effects of polishing and parboiling on proximate composition, structure, phenolic compounds, antioxidant activity, cooking time and hardness of IAC-600 black rice cultivar and MPB-10 red rice lineage. Proximate analysis and light micrographs revealed higher migration of red rice proteins than black rice proteins to the endosperm as a result of parboiling. Parboiling reduced the ash content of red rice while no difference was determined in black rice. Gelatinized starch granules from both genotypes showed similar appearance. There was a decrease in relative crystallinity on both black and red rice subjected to parboiling, which was an indicative of crystallites disruption. Polishing removed more than 90% of free phenolics for both genotypes, while parboiling allowed the partial preservation of free phenolics content in polished rice. Parboiling induced an increase in the cooking time of red rice, but a decrease in the cooking time of black rice.

Propriedades de pasta de amidos de arroz nativo e acetilados

O amido de arroz apresenta características favoráveis a muitas aplicações industriais; no entanto, a natureza hidrofílica do amido na forma nativa pode apresentar algumas limitações para determinados tipos de processamento. Neste estudo, amido de arroz com médio teor de amilose foi acetilado sob catálise alcalina em duas condições reacionais para produzir acetatos de amido com diferentes graus de substituição (GS). A introdução de grupos acetila ao amido foi confirmada por espectroscopia de infravermelho com transformada de Fourier (FT-IV) e os acetatos de amido produzidos foram avaliados quanto às suas propriedades de pasta em viscoamilógrafo (RVA). A acetilação ocasionou reduções em todas as propriedades de pasta avaliadas (temperatura de pasta, viscosidade mínima, pico de viscosidade, viscosidade final e tendência à retrogradação), sendo a redução mais intensa no amido acetilado com maior GS.