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关键词： Functional properties   Pearl millet cultivars (ashana   demby   Morphological properties   Pepsin   Starch yield  

摘要： Influence of enzymatic and SO2 treatments on the yield, physicochemical, functional, morphological, and colour properties of starches isolated from pearl millet (Ashana and Demby cultivars) was studied. The treatment conditions were;control (steeping for 24 h with 0.2% SO2), B (steeping for 7 h with 3 h in distilled water and 4 h in 0.1 M sodium acetate buffer pH, 4.5), S (steeping for 7 h with 3 h in distilled water and 4 h in 0.2% SO2), BE (steeping for 7 h with 3 h in distilled water and 4 h in 0.1 M sodium acetate buffer pH (4-4.5) + 250 mg pepsin) and BES (steeping for 7 h with 3 h in distilled water and 4 h in 0.1 M sodium acetate buffer pH, 4.5, + 250 mg pepsin + 0.2% SO2). The result showed that starch yield from the treatment BE, BES and S was significantly (p <= 0.05) higher than that of B and control treatments in both cultivars. From the micrographs studies, the hydrolytic effect of pepsin on protein matrix attached to the starch could be observed as holes created on the surface of starch granules. All treatments significantly (p <= 0.05) affected the amylose content and pH value of both starches, while the falling number and acidity were not affected (p >= 0.05) by these treatments compared to controls. Water absorption capacity and fat absorption capacity reduced significantly in all treated starches from the two pearl millet cultivars, while viscosity increased following treatments in both cultivars except treatment S (p <= 0.01). In conclusion, functional properties and yield of starch from both millet cultivars were improved by using a combination of enzyme and SO2 during wet milling process.

关键词： Non-centrifugal cane sugar   Palm sugar   Coconut sugar   Physicochemical property   Antioxidant activity   Volatile component  

摘要： Unrefined non-centrifugal sugars in Southeast Asia emanate from various plant sources including sugarcane, palm, and coconut. To assess food and flavor characteristic differences of these unrefined sugars, seven cane, three palm, and two coconut sugars were evaluated in term of their physicochemical, antioxidant, and volatile flavor properties. Results indicated that unrefined sugars from cane had significantly higher ICUMSA color value than palm and coconut sugars, yet they possessed comparable total soluble solid levels. Cane sugars also presented superior phenolic and flavonoid contents and antioxidant activities, particularly in Thai and Japanese products. Each sugar had distinct volatile flavor composition, comprising acids, Maillard reaction products (furanone, pyrazine, furan, and pyrrole), aldehydes, alcohols, and sulfurs. All traditionally made unrefined sugars had significantly greater Maillard reaction products and less acetic acid than in industrially manufactured cane sugars. Then, propanoic acid and [R-(R*,R*)]-2,3-butanediol were solely major volatiles in palm sugars from Thailand. Additionally, mass spectrometry-based electronic-nose (e-nose) profiling detection provided specific ion masses from various volatile components as potential chemical markers in monitoring aroma characteristic of unrefined sugars and differentiated these sugars into nine statistical clusters based on their materials and origins, wherein palm sugars from Thailand and Indonesia, as well as cane sugars from Thailand and Japan, had comparable volatile profiles.

关键词： honey   microbiological quality   probiotic   geographical origin   water content  

摘要： The geographical origin of honey affects its composition, which is of key importance for the health-promoting properties and safety of the product. European regulations clearly define the physicochemical requirements for honey that determine the microbiological quality. On the other hand, legislation abolishes microbiological criteria. In the study 40 honey samples originating from two different climatic zones were analyzed. The water content, pH, water activity analysis and the microbiological quality of honey samples have been tested using the reference plate method (total viable count, yeast and molds, lactic acid bacteria, Bacillus spp.). The cluster classification showed that total viable count of bacteria could be used as a measure alternative to the count of Bacillus spp. and 70% of honeys from the tropical climate zone had different microbiological quality than honeys from the temperate climate zone but still under the level 3.0 log cfu/g. The study has revealed that geographical origin of honey may significantly affect the quality and safety of honey. It was considered that water content can be the most informative and handy marker of the microbiological quality of honeys. Analysis of lactic acid bacteria showed temperate climate zone honeys as a source of beneficial bacteria in the diet.

关键词： Aloididae aloidi   enzymatic hydrolysates   high-pressure processing (HPP)   Maillard reaction   flavour  

摘要： Maillard reaction (MR) plays a crucial role in food processing and storage, and Maillard reaction products (MRPs) contribute to improve flavour of foods. In this study,Aloididae aloidienzymatic hydrolysates lyophilised powder coupled with high-pressure processing (F-1) and atmospheric pressure (F-2) was used to evaluate physicochemical and flavour properties after MR. Compared with F-2, F(1)has not only higher organic acid, 5 '-nucleotides and free amino acid (FAA) content, but also a reduced proportion of bitter amino acids. After MR, significant changes in MRPs were found, such as the accumulation of intermediate and browning products, the decline of pH. Furthermore, the content of FAAs and 5 '-nucleotides in MRPs showed an obvious decrease, whereas the total content of organic acid increased. In addition, the electronic nose (e-nose) and gas chromatography-mass spectrometer (GC-MS) results showed that the content of volatile compounds with meaty flavour increased in MRPs and aldehydes with fishy flavour obviously decreased. To sum up, the enzymatic hydrolysis coupled with high-pressure processing and MR can better improve the flavour.

关键词： Pediatric   Polymeric drug delivery systems   Lyophilization   Solid-state   Mucoadhesive   Buccal delivery  

摘要： Buccal matrices represent a widely accepted dosage form permitting a convenient, easy, reliable drug administration and reducing administration errors. The aim of this study was the development of mucoadhesive buccal matrices for propranolol administration in children. Matrices were obtained by freeze-drying of drug loaded polymeric solutions based on gum tragacanth (GT), pectin (PEC), hydroxypropylmethylcellulose (HPMC), sodium hyaluronate (HA), gelatin (GEL), chitosan (CH) or a mixture of CH and HPMC (CH/HPMC). Matrices were characterized for drug solid state, morphology, water-uptake, mucoadhesion ability, in vitro drug release and permeation through porcine epithelium. The most promising formulations were tested for in vitro biocompatibility in human dental pulp fibroblasts. The preparative method and the polymeric composition influenced the drug solid state, as a complete amorphization as well as different polymorphic forms were observed. GEL and PEC guaranteed a fast and complete drug release due to their rapid dissolution, while for the other matrices the release was influenced by drug diffusion through the viscous gelled matrix. Moreover, matrices based on CH and CH/HPMC showed the best mucoadhesive properties, favoured the drug permeation, in virtue of CH ability to interfere with the lipid organization of biological membrane, and were characterized by a good biocompatibility profile. (C) 2020 American Pharmacists Association (R). Published by Elsevier Inc. All rights reserved.

关键词： Nanoparticle stability   Liposomes   Hydrophobic effect   Thermodynamics   Kinetics   Lipid transfer  

摘要： Liposome-based nanoparticles (NPs) comprised mostly of phospholipids (PLs) have been developed to deliver diagnostic and therapeutic agents. Whereas reassembled plasma lipoproteins have been tested as NP carriers of hydrophobic molecules, they are unstable because the components can spontaneously transfer to other PL surfaces-cell membranes and lipoproteins-and can be degraded by plasma lipases. Here we review two strategies for NP stabilization. One is to use PLs that contain long acyl-chains: according to a quantitative thermodynamic model and in vivo tests, increasing the chain length of a PL reduces the spontaneous transfer rate and increases plasma lifetime. A second strategy is to substitute ether for ester bonds which makes the PLs lipase resistant. We conclude with recommendations of simple ex vivo and in vitro tests of NP stability that should be conducted before in vivo tests are begun. (C) 2021 Elsevier Inc. All rights reserved.

关键词： High oxygen   Carbon monoxide packaging   Dark cutting beef   Bacterial spoilage   Total volatile basic nitrogen  

摘要： The objective was to evaluate the effect of packaging conditions on bacteriological and biochemical changes in beef steaks classified here, as normal ultimate pH (pHu;5.40-5.79), intermediate pHu (5.80-6.09) or high pHu (>= 6.10). Steaks were packaged in vacuum packaging (VP) and modified atmosphere packaging with high oxygen (HiO(2)-MAP) or carbon monoxide (CO-MAP). Headspace, bacterial counts, total volatile basic nitrogen, pH, purge loss, surface color, lipid oxidation, and sensory attributes were monitored over a 14-day storage period at 2 degrees C. HiO(2)-MAP and CO-MAP of high pHu steaks resulted in a bright red color even when observed to be spoilt. Reduced purge loss and lipid oxidation, as well as increased sensory acceptability were observed for steaks with elevated pHu. Higher pHu was also accompanied by an acceleration of microbial proliferation. Of all packaging types investigated, CO-MAP exerted the best preservation, regardless of pHu and based on its antibacterial and antioxidant properties.

关键词： biocompatibility   electron beam irradiation   poly(methyl methacrylate)   sterilization  

摘要： Electron beam (E-beam) irradiation is an attractive and efficient method for sterilizing clinically implantable medical devices made of natural and/or synthetic materials such as poly(methyl methacrylate) (PMMA). As ionizing irradiation can affect the physicochemical properties of PMMA, understanding the consequences of E-beam sterilization on the intrinsic properties of PMMA is vital for clinical implementation. A detailed assessment of the chemical, optical, mechanical, morphological, and biological properties of medical-grade PMMA after E-beam sterilization at 25 and 50 kiloGray (kGy) is reported. Fourier transform infrared spectroscopy, thermogravimetric analysis, and differential scanning calorimetry studies indicate that E-beam irradiation has minimal effect on the chemical properties of the PMMA at these doses. While 25 kGy irradiation does not alter the mechanical and optical properties of the PMMA, 50 kGy reduces the flexural strength and transparency by 10% and 2%, respectively. Atomic force microscopy demonstrates that E-beam irradiation reduces the surface roughness of PMMA in a dose dependent manner. Live-Dead, AlamarBlue, immunocytochemistry, and complement activation studies show that E-beam irradiation up to 50 kGy has no adverse effect on the biocompatibility of the PMMA. These findings suggest that E-beam irradiation at 25 kGy may be a safe and efficient alternative for PMMA sterilization.

关键词： Arachin   Basil seed gum   Composite gels   Calcium chloride   Sodium chloride   Gel properties  

摘要： In this study, the effects of calcium chloride (CaCl2) and sodium chloride (NaCl) with different concentrations (0-20 mM) on the properties of arachin and basil seed gum composite gels were investigated. The results showed that the G', G '' and gel strength of the composite gels were enhanced by Ca2+ and Na+ at a low concentration and decreased at high concentrations. An appropriate concentration of Ca2+ or Na+ (10 mM) strengthened the electrostatic forces, hydrophobic interactions, hydrogen bonds, disulfide bonds and facilitated a conformation conversion of the secondary structures from alpha-helix to beta-sheet. These changes were responsible for the improved hydration properties including water-holding capacity, freeze-thaw stability and swelling behavior of the composite gels in the presence of 10 mM Ca2+ or Na+, which could be explained by the images of compact and uniform microstructures. High concentration of salt ions (15-20 mM) hindered the formation of regular gel network. These findings may facilitate the design of arachin-based gel products with improved texture and sensory characteristics.

关键词： Agavins   Fat-reduced yogurt   Fat mimetic   Texture  

摘要： In this work, agavins (agave plant fructans) potential as fat replacer in dairy products was evaluated. Yogurt nonfat and fat reduced samples were prepared, agavins from Agave angustifolia and A. potatorum species were added to fat reduced products to evaluate their effect on the physicochemical, rheological, and sensory properties in the final products. Significant differences in the viscosity, syneresis and water retention capacity were observed among samples. All yogurts exhibited characteristics typical of a weak viscoelastic gel (G'>G") and strainthinning behavior. Physicochemical and rheological differences were strongly related to the agavins amount in yogurt fat-reduced samples. Agavins did not impact sensory attributes such color, smell, and taste in fact;they improved mouth feel and texture. HPAEC-PAD profiles demonstrated that agavins remain unaffected along the yogurt elaboration process. FTIR spectra showed remarkable differences on all final products composition, been more evident on fatty acids and carbohydrates regions. FTIR-PCA models allowed samples classification among treatments and samples discrimination according to the agavins content. Agavins addition to dairy products has a great potential as functional ingredient in the manufacture of low-fat, prebiotics and symbiotic products. Finally, compiled information increases our knowledge on the broad technological functionality that agavins may have in other food industry niches.