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关键词： Salt reduction   Kokumi   Fermented sausage   Glutamyl peptide   Cheese powder  

摘要： Cheese powder addition to dry-fermented sausage was assessed as a tool to boost flavour and reduce salt content. The effect of different type of cheese powders (mixtures of different types of hard cheeses) and salt content (standard and 40% reduction) on physicochemical and sensory characteristics of dry-fermented sausages was evaluated. Both salt and cheese powder had an effect on physicochemical parameters, whereas only salt had an effect on the sensory attributes of fermented sausages (saltiness, sourness, flavour intensity and complexity). The increase of flavour intensity and sourness when cheese powder is added might confirm the cheese powder potential as a flavour enhancer. Several gamma-glutamyl dipeptides were identified in dry-fermented sausages and cheese powders. The presence of gamma-glutamyl dipeptides in dry-fermented sausages and cheese powders suggest they might influence the kokumi perception.

关键词： Uranium   water quality index   Physico-chemical parameters   Pithoragarh  

摘要： The paper deals with the seasonal variation of physico-chemical parameters in natural spring water sources collected from Pithoragarh city, Uttarakhand, India. A total of sixteen parameters were investigated for pre-monsoon and post-monsoon seasons during the study. Total dissolved solids have been found to range from 315 to 729 mg/L during pre-monsoon and 245 to 704 mg/L during post-monsoon. Total hardness and total alkalinity were observed to be high for two samples. Water quality index was evaluated to determine whether the use of water samples for drinking purpose is safe or not and its values range between 35.71 and 74.39 during pre-monsoon and 31.66 and 72.60 during post-monsoon.

关键词： Torrefaction   Food waste   Compositional analysis   Elemental analysis   Higher heating value (HHV)  

摘要： This study evaluated the change in physical and chemical properties of sun-dried food waste, during torrefaction in a fixed bed reactor. Torrefaction was carried out at different temperatures 230 degrees C, 260 degrees C, and 290 degrees C, for different residence times of 15, 30, 45, 60, 75, and 90 min in a fixed bed reactor. The solid torrefied products were analyzed by elemental analysis, proximate analysis, compositional analysis, and thermogravimetric analysis (TGA), and it was found that most suitable residence time for torrefaction was 60 min as torrefaction beyond 60 min did not yield much improvement in changing the properties of kitchen food waste. Carbon content increased from 46.0 to 58.5%, consecutively increasing higher heating value (HHV) from 16.1 to 21.9%. Compositional analysis demonstrated that there was not much hemicellulose left in the raw food waste after cooking;however, it had cellulose in significant proportion which went through decomposition during torrefaction. Lignin was not affected much. Various process parameters such as mass yield, energy yield, and energy density were also studied, and it was found the mass and energy yield decreased by 65.0% and 47.5%, respectively, and energy density increased by 35%. Van Krevelen indicated clearly that torrefied char had achieved coal characteristics.

关键词： Peanut polysaccharide   RG-I   Fine structure   Physicochemical properties  

摘要： In this work, the fine structure and physicochemical properties of acidic peanut polysaccharide (APP) from sediment of aqueous extraction process were investigated. Methylation results revealed that arabinose, galactose, rhamnose, xylose and 1,4-linked galacturonic acid together constituted the APP, of which arabinose occupied 58.5%. The degree of branching of APP was 63.61%. Combining with 1D/2D NMR analysis indicated a large amount of highly branched 1,5-?-arabinan were formed by multi-substituted ?-Araf residues and a few ?-Galp residues were connected each other. The multi-substituted ?-Rhap residues and ?-1,4-GalpA were linked through 1,2 or 1,4-O-glycosidic bonds, maintaining the core structure of APP. Moreover, partial Araf residues were linked to the Rhap residues through 1,3-O-glycosidic bond. This indicated the presence of RG-I region in APP. Meanwhile, the ratio of RG-I approximately was 83.9%. The proportion of (Ara + Gal)/Rha was 8.5, suggesting the abundant neutral side chains to the RG-I. HG region occupied 4.4% of APP. On the other hand, APP exhibited strong charge and high transparency at pH3.5?11.0. Meanwhile, the turbidity of 15.0% APP only was 0.18. Divalent cations (Ca2+, Fe2+ and Zn2+) were strongly bound to APP. Moreover, the APP-Fe2+ complex formed strong gel. This information would be helpful for exploring the application of APP.

关键词： Bioactive   Whey protein   Polyphenols   Concentrated dispersions   Physico-chemical properties  

摘要： Occasionally, bioactive ingredients desired for encapsulation (such as polyphenols) naturally interact with the structure-forming food components intended for their protection and delivery. Non-covalent protein-polyphenol conjugation interactions have been reported to occur naturally under mild pH and temperature conditions, causing changes to protein structures and consequent functionality. Highly concentrated liquid dispersions of varied solids contents, ratios of whey protein isolate (WPI) to sucrose contents, and Aronia berry polyphenols contents were formulated and analyzed to determine potential effects of protein-polyphenol conjugation in the system on the physical properties of dispersions. Dispersions were characterized by rheological measurements, flow testing, particle size analysis, centrifuge separation, and drop sizes produced, and microstructures were visualized with optical light microscopy. Addition of polyphenols was found to alter dispersions physical characteristics including increased viscosity and surface tension and reduced particle size of dispersions, with changes being attributed to conjugation interactions between proteins and polyphenols.

关键词： Bambusa vulgaris   fibers   creep   Young's modulus   linear density  

摘要： In this study on characterization of bambusa vulgaris fibers from Cameroon (BV), we evaluated the linear density as well as the moisture uptake. With the help of SEM, the cross-sections were observed to be circular shapes;they increase from outside to inside in any transverse position along the stem. Also, the degradation temperature of BV was investigated with the aid of TGA and the result showed that the degradation temperature of BV fibers is between 366 degrees C and 380 degrees C. In addition, their Young's moduli in dynamic tensile test was determined and it was noticed that the Young moduli increase from inside to outside. The bending tests of BV fibers were carried out and enable the various parameters in zone 3/3. Finally, the creep behavior of BV fibers was studied and it was revealed that the 4-element Burger model describes very well this phenomenon and could help in well predicting fatigue behaviour of BV fibers reinforced composites.

关键词： Honey   Quantitative Spectrometric Variety-Activity Relationships   ABTS   DPPH  

摘要： Algeria is a country rich in natural resources;however, exports towards industrial countries required high food quality standards, which demand progresses within industry's food control systems. This work was lead to evaluate the quality of 12 purchased honey samples from different origins from Algeria. Physicochemical properties, total flavonoid contents, antioxidant and antimicrobial activities by a spectrophotometric method and spectral print of honey by Raman microscopy and UV-Vis spectroscopy. The results obtained indicate a good quality level and good maturity. The discrimination between honey types was achieved by multivariate data analysis (principal component analysis and hierarchical cluster analysis). This study provides for the first time the Quantitative Spectrometric Variety-Activity Relationships (QSV-ARs) developed for predicting the antioxidant activities (DPPH and ABTS).

关键词： Broido&apos   s plot   cellulose fiber   chemical treatments   mechanical and thermal properties   Weibull analysis  

摘要： First time, this study reports the effect of benzoyl chloride (BC), potassium permanganate (PP), and stearic acid (SA) treatments on the surface morphology, physical, chemical, structural, mechanical, and thermal properties of cellulosic fiber obtained from date palm plant petioles. Morphology analysis displayed the existence of protrusions on treated fiber surface, which stimulates the mechanical interlocking between the fiber and polymer matrix. Highest cellulose (67.22%) and lowest hemicellulose (9.25%), lignin (14.02%), ash (3.25%), wax (0.10%), and moisture (8.93%) content were observed in SA-treated fibers than others. Similarly, highest weight loss (20.80%), reduced diameter (0.3166 mm), and density (0.389 g/cc) were obtained in SA-treated fibers than the other fibers investigated. Outcomes of FT-IR spectra evident the presence of cellulose and partial removal of non-cellulosic constituents in BC-, PP-, and SA-treated fibers. Enhanced crystallinity index (69.5%) and crystallite size (7.43 nm) values of SA-treated fiber indicated the elimination of amorphous lignin and hemicellulose, and made the structure to be more crystalline which supports to obtain higher tensile properties (tensile strength of 489.07 MPa and tensile modulus of 9.4 GPa) than others. Maximal degradation temperature of SA-treated fiber was 328.86 degrees C and also having kinetic activation energy of 90.7 kJ/mol.

关键词： High-pressure homogenisation   Bread   Texture   Image analysis  

摘要： This study aimed to investigate the physicochemical and textural characteristics of bread produced from doughs composed of high-pressure homogenization (HPH) treated flour slurries. For this purpose, bread samples were produced from doughs composed of HPH treated flour slurries at 0 (control), 20, 30, 50, and 70 MPa. HPH treatment resulted in decreased particle size with more uniformity in flour slurries. A monomodal particle size distribution was determined in slurries. HPH obtained higher firmness, consistency, and cohesivity in slurries. In bread samples, HPH increased yellowness and lightness values. The bread samples prepared from HPH treatment had 1.09-1.25 times higher specific volumes than the control sample. HPH treatment provided decreased hardness and increased cohesiveness and springiness values. Image analysis results showed HPH treatment decreased total cell count, whereas increased mean cell area of bread samples. The findings revealed that HPH treatment results in higher quality bread compared to control.

关键词： Spices   Fixed oil   Physicochemical properties   DSC   Nutraceuticals  

摘要： Spices and herbs are well appreciated for their medicinal properties since ancient times. Till date, spices are being explored for volatile oils (essential), flavour and for addressing many chronic diseases. In the present study, we investigated the physicochemical properties, fatty acid composition, differential scanning calorimetry (DSC), elemental composition and nutraceutical compounds of fixed oils (non-volatile) from five selected spices viz.,Alpinia galanga, Cinnamomum zeylanicum,Trigonella foenum-graecum, Foeniculum vulgare,andMyristica fragrans. The fixed oil (FO) content of volatiles-free powders of the five selected spices ranged from 1.58% (C. zeylanicum) to 26.43% (M. fragrans). The studied FO showed a good quality index which was analysed by estimation of free fatty acids, iodine value and unsaponifiable matter. The fatty acid analysis showed high palmitic acid in the FO ofA. galangaandC. zeylanicum. High linoleic, oleic, and myristic acid levels were observed inT. foenum-graecum,F. vulgareandM. fragransFOs, respectively. The nutraceutical compounds such as total phenolics were high inC. zeylanicumFO (0.53%). Hence the studied FO could be an excellent alternative to oil nutraceutical compounds. It may be used as a functional ingredient in foods which needs further validation for value addition.