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关键词： Functional properties   Insect-containing bread   Insect powder   in vitro digestion   Lactic acid bacteria   Sourdough  

摘要： Powdered mealworm (MW) and buffalo worm (BW) larvae were used to functionalize sourdough Italian-style breads. Sourdough inoculum was started with Levilactobacillus brevis, Weissella cibaria and Leuconostoc citreum. The doughs were SBS (semolina plus powdered BW larvae and sourdough) and SMS (semolina plus powdered MW larvae and sourdough) whose pHs (4.32 and 4.21, respectively) were higher than that of control (3.81). The highest fermentation quotient (lactate/acetate molar ratio) was recorded in SMS (4.46). LAB reached viable counts of about 109 CFU g-1 in almost all doughs. Insects impacted bread VOCs with dodecanal, 2.4-dodecadienal and 2-octenal-2-butyl. SBS and SMS increased the antioxidant capacity of breads by 42 and 69%, respectively. SMS decreased the glucose release in the bio-accessible fraction by 70% reducing the glycemic index of bread. Control breads were more appreciated by the sensory panel than insect-containing breads, though SMS breads were characterized by a slightly lower overall assessment.

关键词： Esters  

摘要： A range of liquid emollient ester-loaded body emulsions were evaluated on the basis of sensory profile, consumer perception, physicochemical, biometrological, and rheological performances. This was complemented by skin hydration and transepidermal water loss (TEWL) studies performed using a Corneometer (R) and Tewameter (R), respectively. The rheological studies showed similar behavior of creams on variation of shear stress, frequency, and temperature. However, skin hydration performances of creams were found varied when compared between base cream and emollient ester-containing creams. In case of the TEWL study, base cream (F1, no ester) and octyl palmitate-containing cream (F2), exhibited the most protective behavior for the skin with minimal water loss. Sensory profiles of creams were obtained using the sensory descriptive analysis method. A study performed with human consumers (as subjects) using the difference of test attributes (directional) method showed the importance of sensory evaluation with consumers and proved to be an interesting analysis for comparison with the sensorial profile. In this case, the attributes with the highest intensity in the evaluated creams were, that is, spreadability, slipping, and dry touch. Stability studies of creams were performed for 90 days under different storage conditions. Stability studies showed octyl stearate-containing (F2) and palmitate-containing (F5) creams exhibited best stability under extended storage conditions. This research has demonstrated the importance of physicochemical characterization and sensory evaluations performed with consumers for more targeted analysis of cream-based formulations to differentiate product characteristics and identify attributes-led preferences. Practical applications Results from the present work suggest that emollients are directly responsible for sensory characteristics such as spreading, absorption, and touch on the skin;they can influence the viscosity and appearance of emulsio

关键词： Biomaterials   Hydroxyapatite   Bio-wastes   Antibacterial   Nanoindentation  

摘要： We report the synthesis of hydroxyapatite (HAp)-based antibacterial biomaterials using a mussel shell as a calcium source and by the integration of silver ions via a wet precipitation method. The silver doping at 2 mol% can provide silver-doped carbonated HAp while at 10 mol% can offer silver-doped carbonated HAp/silver oxide nanocomposite. The synthesized Ag-integrated samples exhibit the H (263-903Mpa) and E (0.96-3.31GPa) almost similar to cancellous bone with good antibacterial inhibition on S. aureus (15 +/- 02 mm) and E. coli (26 +/- 02 mm) growth. Hence, they can be a potential precursor to make bone fillers for the treatment of bone infections.

关键词： Polylactic acid   Carbon nanofillers   Melt extrusion   Physico-chemical properties   Structure characterization   Mechanical reinforcement  

摘要： Polylactic acid (PLA) is the most wide-scale investigated biodegradable and renewable under specific processing conditions thermoplastic polyester. As bioplastic material, it has the potential to be used as a substituent of conventional polymers derived from fossil fuel resources. The drawbacks possessed by PLA as poor thermal and electrical properties, mechanical brittleness, and ability to undergo polymer chain degradation in ambient medium could be overcome by incorporation of carbon nanofillers in the PLA matrix. Raman spectroscopy was used to study the effect of graphene nanoplatelets (GNPs) and multiwall carbon nanotubes (MWCNTs) on the nanocomposite molecular morphology and structure. The carbon nanofillers impact on the crystallinity of the melt blended hybrid material and the changes in the composite architecture were defined by applying of physical methods as X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Thermo-gravimetric analysis (TGA) was implemented to outline the thermal properties of the nanocomposites. An excellent homogeneity and firmly expressed crystalline structure of the produced composite materials were disclosed. Tensile testing showed that coupling GNPs and MWCNTs has higher positive effect on ultimate tensile strength of the nanocomposites and lower influence on Young's modulus of elasticity.

关键词： epoxy-4   4'-isopropylidenediphenol resin   carbon nanotubes   active diluent   surface functionalization   homogenization   physicomechanical properties  

摘要： The possibility of using Taunit carbon nanotubes as modifying additives to fiber-reinforced polymer composites based on an epoxy resin and basalt roving was examined. The optimum content of nanotubes in the epoxy compound, at which carbon nanotubes reinforce the epoxy composite, was chosen. The possibility of modifying the nanotube surface with a dressing additive, gamma-aminopropyltriethoxysilane, for enhancing the adhesion of the nanotubes to the epoxy resin was considered, the modification efficiency was determined, and the effect of UP-616 active diluent on the system was examined. The effect of nanotubes and active diluent on the polymer curing was studied by the thermometric method and differential scanning calorimetry.

关键词： the Andes   conservation   global change   high mountain lakes   neotropics   trophic state   wetlands  

摘要： The paramo lakes, Colombia, situated in the neotropical region, are of great value both as natural heritage and as water source to the most populated areas of the Andes, but are threatened by expanding agriculture, livestock, mining, and landscape fragmentation. Nonetheless, a general assessment of the lakes' distribution and biogeochemical characteristics was lacking. We made a complete inventory of the Colombian paramo lakes and characterized their morphometry and water chemistry based on a survey of 51 lakes in the Eastern Cordillera. There are 3250 lakes distributed across 28 paramo complexes in Colombia, mainly located between 3600 and 4400 m a.s.l. The lakes are usually small (<10 ha) and shallow (<10 m). Most of them are slightly acidic (average pH similar to 6), with high nutrient (total phosphorus similar to 0.6 mg/L, total nitrogen similar to 1 mg/L) and total organic carbon (similar to 6 mg/L) concentrations and low oxygen (similar to 3.5 mg/L) at the bottom. Water chemistry varies according to two main independent gradients related to watershed bedrock geology and trophic state. Global change pressures may be challenging the preservation of these unique ecosystems. Increasing the protection of more lake watersheds should reduce these potential impacts by mitigating negative synergies with local pressures.

关键词： Antioxidant   Dill   Functional food   Set yogurt  

摘要： In the present study, dill extract was used in yogurt in order to increase its consumption acceptability and promote its functional properties. Milk fortified with 0, 5 and 10% (wt /vol) dill extract and its pH, acidity, total phenolic compounds, DPPH inhibitory percentage, viscosity, syneresis, water holding capacity, color and sensory properties were evaluated after 1, 7, 14 and 21 days of production. Investigation of the results showed that with the increase of the extract amount, inhibition percentage and total phenolic compounds increased, significantly (P < 0.01). The effect of storage time was also significant on the indexes, in a way that antioxidant properties and phenolic compounds increased in all treatments until 7 days and then it decreased. Also, the effect of treatment type was significant on some physicochemical characteristics (such as pH, acidity, viscosity, syneresis and water holding capability) of the fortified yogurt (P < 0.01). The results of the color evaluation indicated that the addition of dill extract reduced the red spectrum (a*) and lightness (L*) and increased the yellow spectrum (b*). In sensory evaluation, the highest score was given to the yogurt with 5% of dill extract.

关键词： Wild banana   Ripening   Texture   Chemical changes   Physical changes   Sensory  

摘要： The changes in various physicochemical and mechanical properties after harvesting wild banana (Musa balbisiana) were investigated by storing the fruit at room temperature (22 +/- 2 degrees C). During ripening, physical changes such as pulp to peel ratio and fruit with seed to peel ratio increased and the changes in the colour of the fruits from green to red while yellowness occurred in the peel. The maximum colour difference (Delta E) of pulp and peel increased up to the 5th stage and decreased thereafter. Textural softening occurred till the end of the ripening stages;the peak force of penetration decreased from 16.6 to 5.8 N for banana samples with the peel. At the end of ripening, a non-significant difference was observed that may be due to equalized mucilaginous peel tissue structure. During the ripening process, moisture content, titratable acidity, pectin, fat, total sugar, pH and the total soluble solids were increased, and decreased starch content, ascorbic acid and protein were observed. The sensory assessment at the 6th stage of the banana received the highest rating. Thus, the present study determined the best ripening stage of wild banana variety to be suitable for processing during the postharvest phase and quality control of processed products.

关键词： Whey   Butter   Chemical composition   Melting profile   Thermo‐   oxidative stability   Colour  

摘要： The objective of this work was to determine the effects of whey composition on the physicochemical properties of whey butter and compare with milk butter based on these properties. Whey samples were obtained from the whey processing plants located in different regions of Turkey. Whey composition influenced the major and minor components of whey butters. Differences among the whey butters were observed on titratable acidy (TA, 0.43-0.55%), acid value (AV, 0.75-0.90 mg KOH/g), moisture (17.33-19.05%), fat (80.23-81.47%), nonfat solid (0.66-1.20%), NaCl (0.10-0.23%), peroxide value (PV, 1.08-1.50 meq O-2/kg), total carotenoids (1.78-2.21 mg/kg), gamma- and total tocopherols (1.06-1.41 and 27.02-27.33 mg/kg, respectively), Ca (73.12-94.72 mg/kg), P (56.03-72.20 mg/kg), K (73.36-140.10 mg/kg), Mg (12.83-18.12 mg/kg), Na (63.95-165.85 mg/kg), total minerals (283.32-485.53 mg/kg), colour (L*, 86.46-89.52 and b*, 12.21-15.52) and certain fatty acids. The milk butters were one- to threefold lower in TA, AV, moisture, NaCl and PV and one- to 3.4-fold higher in fat, nonfat solids, protein, total carotenoids, alpha-, gamma- and total tocopherols, Ca, P, K, Mg and total minerals. Whey butters were distinctly brighter and less yellower. Butter source had no effect on iodine value (35.39 +/- 0.15 g I-2/100 g), saponification value (225.22 +/- 0.17 mg KOH/g), beta-tocopherol (0.41 +/- 0.02 mg/kg), certain fatty acids, melting characteristic and thermo-oxidative stability. The cluster analysis enabled the division of whey and milk butters into two separate groups. These results highlighted that partial transfer of certain compounds from milk to whey during cheese manufacturing and biochemical and chemical changes such as lipolysis, hydrolysis and oxidation that occur in the period from the whey production to butter processing were largely responsible for the differences in the whey and milk butter properties.

关键词： 2D lamellar sheets   coconut oil   colloidal dispersion   grease   lubrication   spherical nanoparticles   synergistic effect  

摘要： The present work addresses the use of synergistic blends of two different types of nanomaterials (spherical particles and lamellar sheets) as additives for coconut oil-based grease formulation to provide the energy-efficient and sustainable alternative to conventional grease. The spherical SiO2 nanoparticles are separately blended with 2D lamellar sheets of MoS2 and graphene oxide (GO) in variable ratio and probed their synergistic effects for enhancement of physicochemical and lubrication properties. The SiO2 nanoparticles, MoS2, and GO nanosheets are prepared by modified sol-gel, hydrothermal reduction, and Hummer's methods, respectively. The 0.05 wt% nanomaterials blends of MoS2/SiO2 (30:70) and GO/SiO2 (50:50) as optimised doses furnished the maximum reduction in the friction and wear. The combination of rolling friction and low shear properties using the synergistic blend of the spherical nanoparticles (SiO2) and nanosheets (MoS2 and GO) showed significant improvement in tribological properties. The optimised blends of nanoadditives, that is, MoS2/SiO2 and GO/SiO2 conserved the energy by 20% and 19%, respectively. These findings suggest that the use of synergistic blends of variable nanomaterials to vegetable oil-based lubricants can pave a direction for new generation lubricant formulation, where environmental sustainability and energy conservation are on prime importance.