Ahmed, ShegawYimam, AbubekerSibhatu, Hagos KaluJabasingh, S. Anuradha...
10页
查看更多>>摘要：This research aims at the utilization of an agro-industrial waste, the brewery spent grains (BSG) for the extraction of a natural antioxidant, the ferulic acid. Brewery spent grain was initially treated with dilute sulfuric acid, and then subjected to alkaline hydrolysis using NaOH, prior to ferulic acid extraction and purification. X-ray diffraction analysis of the raw and hydrolyzed BSG showed the evidence for a possible release of phenolic extractives. The effect of extraction time (100, 120 and 140 min), temperature (60, 90, and 120 degrees C), and alkali concentration (1, 2 and 3% (w/v) on the ferulic acid yield was optimized by the Box Behnken Design, using Response Surface Methodology. Accordingly, the experimental ferulic acid yield obtained at optimized conditions (90 min, 120 degrees C and 2% (w/v) NaOH concentration) was determined to be 46.17 mg/100 g BSG. The total phenolic, flavonoid, protein and reducing sugar content of ferulic acid extract were measured. Antioxidant activity was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical assay. Fourier Transform Infrared Spectroscopy (FT-IR) and High-Performance Liquid Chromatography (HPLC) analysis confirmed the presence of ferulic acid. Results of this present research provides an alternative insight into the waste management of BSG through ferulic acid extraction.
查看更多>>摘要：Human milk (HM) is the best source of nourishment for infants, but it must be fortified for optimal growth of premature babies. Hydrolyzates of bovine milk proteins are used for fortification of pasteurized donor HM (PDHM). In the present work, peptidomic approach was applied to characterize three commercial fortifiers. These products, intended for premature infant nutrition, are commonly used in neonatal intensive care units. Besides intact fortifiers and PDHM, digests of (un)fortified PDHMs (after preterm in vitro static gastrointestinal digestion, SGID) were investigated. Specifically, 186 unique peptides were revealed among the three fortifiers, 21 potential bioactive peptides (BPs) among them. After SGID of fortified PDHMs, 515 unique peptides were identified. They originated mostly from human beta-casein; 15 were homologous to potential BPs of human and bovine milk protein origin. This work represents one of the few peptidomic investigations on fortifiers and fortified PDHM after a simulated preterm infant digestion.
查看更多>>摘要：The objective of this work is to explore a new pathway to develop active packaging materials. Currently, controlled release materials have attracted considerable attention in food packaging applications. In this study, the thyme essential oil (TEO) was loaded in electrospinning porous poly(lactic acid) (PLA) nanofibers and coated with poly(vinyl alcohol)/poly(ethylene glycol) (PVA/PEG) blends for humidity-controlled TEO release. The images of scanning electron microscope displayed uniform pores distributed on the surface of PLA nanofibers. Water contact angle measurement indicated that PVA/PEG coating provided the packaging film with excellent hydrophilicity. ATR-FTIR spectral analysis supported the chemical composition of the films. The antibacterial activities of PLA/TEO/PVA/PEG films against Escherichia coli and Staphylococcus aureus reached >99%. Furthermore, the weight loss and firmness of strawberries packaged with this novel film were evaluated. Finally, the in vitro release behaviors of TEO were evaluated and the results demonstrated that the release rate could be controlled by adjusting the humidity (20% RH to 80% RH).
查看更多>>摘要：Coffee is the most consumed beverage in the US and several other countries such as Brazil and Colombia. Coffee has been recognized for a myriad of health benefits including those arising from its antioxidant properties. However, to the best of our knowledge, there is no literature addressing the fate of phenolic compounds from espresso capsules considering the role of caffeine as well as the interaction with milk upon in vitro digestion. In this study, regardless of the sample (regular or decaffeinated espresso coffee capsule), oral and gastric digested samples showed lower contents of caffeine and phenolic acids than their undigested counterparts. In contrast, with recovery of up to 48%, only caffeic acid was present in the intestinal phase. Regular coffee samples showed a prooxidative action during the intestinal phase. In contrast, decaffeinated coffee prevented milk lipid peroxidation during the gastric and intestinal phases. A significant positive correlation existed between the caffeine concentration and the milk lipid peroxidation during the gastrointestinal phase. Thus, under the experimental conditions employed, decaffeinated coffee from commercial espresso capsules was considered the best choice in terms of prevention of the potential exposure of the gastrointestinal tract to products of milk lipid peroxidation.
查看更多>>摘要：This study aimed to explore the core microbiota involved in the production of volatile flavor compounds during the fermentation of traditional Koumiss. Microbiological analysis based on high-throughput sequencing (HTS) demonstrated that Lactobacillus, Lactococcus, Acetobacter, Streptococcus, Serratia, and Leuconostoc bacteria as well as Kazachstania, Kluyveromyces, Trichosporonaceae, Pichia, and Candida fungus were the predominant genera during the traditional fermentation process. A total of 112 volatile compounds were identified in fresh mare's milk and during the simulation of the traditional brewing process. Heatmaps and Cluster Analysis revealed that the flavor formation of Koumiss is largely determined by the types and contents of acids, esters, and alcohols. Furthermore, the correlations between microbiota succession and volatile flavor dynamics were explored through bidirectional orthogonal partial least squares (O2PLS) based correlation analysis. Four bacterial genera (Lactobacillus, Acetobacter, Lactococcus, Pseudomonas), and two fungal genera (Kazachstania, and Candida) were determined as the core microbiota for production of the main volatile flavor compounds of Koumiss. The information provided in this study is beneficial in understanding the fermentation mechanism of traditional Koumiss, and to provide a theoretical basis and quality control guidance for the semi-industrial or industrial production of Koumiss.
Paula Lopez-Fernandez, MariaCristian Favre, LeonardoDavid Rodriguez, SilvioMaria Busch, Veronica...
9页
查看更多>>摘要：The aim of the present study was to evaluate the physicochemical, thermal and pasting properties of the starch of six quinoa genotypes native to the northwest of Argentina. The genotypes belonging to two genotype groups, highlands and dry valley, were grown in Jujuy, Argentina. Significant differences among genotypes were observed (P < 0.05) in amylose content, swelling power, water-binding capacity, thermal and pasting properties. In the different genotypes, the starch was characterized by a typical A-type X-ray diffraction pattern, with relative crystallinity ranging between 26.1 and 28.5%. Granule-bound starch synthase (GBSS), which is the single enzyme responsible for amylose biosynthesis, was also identified, with the 67- and 58-kDa quinoa poly-peptides corresponding to the full-length and mature GBSS proteins. Studies of the pasting properties showed that the starch of the genotypes from the highlands had lower peak viscosity and lower breakdown parameter than that of the genotypes from the dry valleys. The results showed that the genotypic background and the environment influence the pasting curves. The novel findings discussed in this study constitute a starting point for research focusing on incorporating innovative technologies in the food and biomaterials industry.
NSTL
Elsevier