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关键词： Turkish coffee   Roasting   Milling   Brewing   Storage  

摘要： Turkish coffee is a special coffee due to its roasting, milling, brewing and storage processes. The roasting, milling, brewing and storage processes mainly affect the quality and physicochemical properties of Turkish coffee. The aim of this study is to determine;i) the optimum roasting method;oven (160, 180, 200 and 220 degrees C), microwave (350, 490, 700 W) or infrared (600, 1200 W), ii) the effects of different milling methods (cutter and hammer), iii) the effects of initial brewing temperature and water hardness, iv) the ideal brewing method (copper and electrical) and v) the ideal storage conditions. Microwave roasting at 350 W for 30 min and grinding with a cutter mill were found to be the better processes when compared to the others. Furthermore, the highest foam volume was obtained by using tap water at 4 degrees C and by brewing with a copper pot. The cold storing of Turkish coffee powder is a good storage condition to preserve the freshness;therefore, higher foam volume and stability were achieved under these conditions.

关键词： diabetes mellitus (DM)   erythrocytes   low-intensity light therapy (LILT)  

摘要： The physicochemical characteristics of erythrocyte membranes from the peripheral whole blood of rats and the erythrocytes washed with physiological solution, using the method of acid hemolysis, under diabetes mellitus conditions and against the therapy based on low-intensity blue light emission in the visible light range have been studied. The use of low-intensity light therapy (LILT) led to a decrease in the resistance of erythrocyte membranes to the action of acid hemolytic in the control group animals. Under diabetes conditions, LILT prolonged total hemolysis and reduced the count of hemolysed erythrocytes relative to the indices in the group of animals with DM. No expressed hypoglycemic effect due to the LILT was observed in sick animals, and the content of glycolysed hemoglobin tended to decrease.

关键词： Rice starch   Drought and heat stress   Morphological structure   Physicochemical properties  

摘要： High temperature (HT) and drought stress (WS) severely affect rice quality by altering the starch structure in rice. The morphological and physicochemical properties of starches isolated from two rice varieties grown under three stress treatment (HT, WS and WS + HT) during the grain filling stage were investigated. The results showed that WS increased amylose content (AC%) and the proportion of large starch granules (LSG) and made the surface of the starch granule smooth and flat. As a result, a lower relative crystallinity, surface order, swelling power, setback viscosity and gelatinization enthalpy were caused. HT decreased AC% and milled rice rate, but increased chalky rice rate, the number of LSG and the large air space and pits on the surface of the starch granules. As a result, a higher relative crystallinity, surface order, swelling power, setback viscosity and gelatinization enthalpy were caused. Similar results were observed under the treatment of WS + HT, indicating that there is a mild antagonistic effect on rice starch when the HT and WS occur simultaneously.

关键词： Common vetch   Starch   Physicochemical property   Functional property  

摘要： It is believed that common vetch (Vicia sativa L.) contains a relatively high quantity of starch. In this study, the starch content of 36 common vetch accessions was monitored, within the range of 20.56-47.53% on a whole seed basis. The amylose content ranged from 17.75 to 38.68% on a dry starch basis. Among them, 8 common vetch accessions were selected for physicochemical and functional analysis, by comparing with 2 smooth pea cultivars and 2 chickpea cultivars. The isolated starches differed significantly in granule morphology, thermal parameters and pasting properties. The shapes of common vetch starch granules were kidney, spherical or oval varied with size from 7.77 to 23.16 mu m. The crystalline structures of all starches were C-type. The relative crystallinity of common vetch starches ranged from 22.70 to 34.32% and gelatinization temperature ranged from 63.10 to 66.80 degrees C. A wider variation of breakdown (BD) (197-910 cp) was observed in common vetch starches than smooth pea and chickpea starches. And the setback (SB) (1314-2221 cP) was lower than that of the pea cultivar P2 and two chickpea cultivars. These could lead common vetch starches to a broad application prospect.

关键词： Rare honey   Palynological analysis   Physicochemical analysis   Biochemical analysis   Volatile compounds   Chemometrics  

摘要： Obtained directly from beekeepers in Portugal and Greece, some rare honey samples were subjected to melissopalynological, physicochemical (degrees Brix, moisture, pH, electrical conductivity, free acidity, total dissolved solids, salinity, liquid resistivity, specific weight, CIELAB colour parameters, Pfund, and colour intensity), biochemical (diastase activity, vitamin C, antioxidant activity, and total phenolic content), and volatile compounds analyses. Results showed that honey samples from Portugal were dominated by pollen grains of Anarrhinum bellidifolium (L.), whereas those from Greece were honeydew of not specific type, possessing a diverse pollen spectrum and few honeydew elements. The implementation of one-way analysis of variance showed significant differences (p < 0.05) among the two honey types in the majority of physicochemical, biochemical, and to a lesser extent in the volatile compounds. These were 34 in total, belonging to alcohols, aldehydes, benzene derivatives, esters, hydrocarbons, ketones, sulfur compounds, and terpenoids. Application of correlation, regression, and stepwise linear discriminant analyses indicated some potential fitting among the investigated parameters, and classified perfectly honey samples according to botanical origin based on electrical conductivity, salinity, 2-methylbutanal, and alpha-pinene, providing a rapid tool for the classification of less common honey types.

关键词： Quinoa   Soluble dietary fiber   Physicochemical property   Functional property  

摘要： As it is well documented that the phytochemical composition and bioactive profile of quinoa are influenced by different phenotypes, we analyzed the physicochemical and functional characteristics of different quinoa soluble dietary fiber (SDF). SDF was prepared through ultrasound-assisted enzymatic extraction from three colored quinoa brans. After purification, the yield of SDF from white (W-SDF), red (R-SDF) and black quinoa bran (B-SDF) was 2.2%, 5.7% and 5.9%, respectively. Compared with R-SDF and B-SDF, W-SDF had a higher molecular weight (1.72 x 10(6) Da) and lower zeta-potential (- 32.16 mV), although their monosaccharide composition and Fourier transform infrared spectroscopy (FT-IR) results showed no obvious differences. The transmission electron microscope (TEM) image suggested that R-SDF exhibited a more complex and loose structure than W-SDF and B-SDF. Moreover, R-SDF exhibited higher thermal stability, gel forming capacity, bile acid binding capacity, water-holding capacity and glucose adsorption capacity than those of B-SDF and W-SDF. Taken together, SDF extracted from quinoa especially from red quinoa might be a promising candidate for the development of novel functional food ingredients.

关键词： Energy utilization  

摘要： This study aimed to evaluate the influence of drying air temperature on drying kinetics and the physicochemical properties of dried bananas. Banana slices were dried at 40, 60, and 80 degrees C. Drying was terminated when the samples had a moisture of 20%. Mathematical models were fitted to the moisture ratio. A generalized model of moisture was developed, to predict the moisture of samples as a function of drying time and temperature. The effective moisture diffusivity (D-eff), activation energy and the drying rate (DR) were calculated. Electrical energy consumption was measured. The moisture, water activity, reducing and total sugar content, acidity, hardness, and color of the dried bananas were evaluated. The moisture decreased during drying, obtaining a mean value of 20.132%. All mathematical models fitted well to the MR data, with a determination coefficient greater than 0.95. The Midilli model was that which best fitted. The higher temperature resulted in higher D-eff (3.538 x 10(-9) m(2) s(-1)) and DR, less drying time (120 min) and electrical energy consumption (4.319 kWh), higher reducing sugar content (47.51%) and hardness (28.187 N), lower acidity (1.038%), more yellow tonality (78.04 degrees), and higher chromaticity (18.49) of the dried bananas. The optimum temperature for drying bananas was 80 degrees C. Practical Applications Banana is a fruit widely consumed in the world. However, it is very perishable, causing great waste and financial loss. Convective drying is a simple and low-cost method, widely used in fruit processing to produce new products and extend the shelf life of food. The dried banana is a product of good sensory acceptance and therefore drying is a good alternative for processing the banana pulp. The temperature of the drying air is one of the principal parameters of this process since it influences the drying kinetics and the physicochemical properties of the dry product. Therefore, it is important to study different drying air temper

关键词： Antarctic krill   crustacean wastes   chitosan   rheology   antimicrobial activity  

摘要： In this work, physicochemical, rheological, and antibacterial properties of chitosan (CS) extracted from white shrimp (WS), giant river prawn (GP), andAntarctic krill(AK) were investigated. The results demonstrated that molecular weight (MW) of commercial chitosan (CCS), WSCS, GPCS, and AKCS were 1175.8, 2130.4, 1293.3, and 1109.3 kDa with the degree of deacetylation (DDA) of 73.5, 74.1, 82.1, and 75.9%, respectively. Fourier transform infrared (FT-IR), X-ray diffraction (XRD), differential scanning calorimetry (DSC), and scanning electron microscope (SEM) were employed to study the structural differences of CS. Moreover, storage modulus (G ') and loss modulus (G '') of AKCS were lower than that of WSCS and GPCS, respectively, but higher than that of CCS. Minimum inhibitory concentration (MIC) and minimum bacterial concentration (MBC) of CS againstEscherichia coliandStaphylococcus aureuswere investigated at concentration between 0.0125 and 1 mg/mL. These results highlighted that AKCS with low viscoelastic properties had a potential application in food and pharmaceutical application.

关键词： Green tea   beta-cyclodextrin   Inclusion complex   UHPLC-LTQ-Orbitrap-MS   FE-SEM  

摘要： Green tea (Camellia sinensis) is a traditional beverage. Its ethanolic extract (GTE) is rich in catechins, has a wide range of associated health benefits. However, the commercial formulations of catechins-rich GTE are limited owing to its low thermal stability and high oxidation sensitivity. In this study, an inclusion complexes of GTE-beta-cyclodextrin (GTE-beta-CD) were prepared by freeze-drying. Structural characteristics of the inclusion complexes were examined using FE-SEM, XRD, FT-IR, and TGA/DTG. After inclusion complexation, the samples were analyzed by UHPLC-LTQ-Orbitrap-MS and the variation in the quantities of each identified metabolite were visualized in the heat map. Results revealed that bioactive components of GTE were successfully included in beta CD cavities and the thermal stability of GTE was increased by complexation with beta-CD. Results of UHPLC-LTQ-Orbitrap-MS confirmed that beta-CD had selective inclusion capacity for bioactive compounds of green tea. A variety of in-vitro antioxidant studies (DPPH, ABTS, and FRAP) revealed that the GTE-beta-CD inclusion complexes contained better scavenging capacity against free radicals. Findings of the present work suggest that the GTE-beta-CD inclusion complexes might have potential applications as functional ingredient and health supplement.

关键词： Textures  

摘要： Preservation in vinegar extends the storage of many food commodities. Since,Agaricus bisporus, an extensively cultivated mushroom is perishable, it demands for postharvest processing to improve its marketability. The present study deals with preparing different dipping solutions using synthetic and natural vinegar for button mushrooms' storage @ 4.5% and 5% acidity with addition of sugar and black pepper. Physico-chemical and nutritional studies were carried out on both vinegar types for 6 months at room temperature. It was observed that color, texture, moisture, and pH ranges superior for 4.5% acidity of vinegar. Polyphenol oxidase and antioxidant activity, vitamins (niacin, thiamine), and nutrients (protein, carbohydrates, fats, free amino acids, and fibers) showed minimum changes during storage of 4.5% natural vinegar dip up to 4 months. The study, thus, proposed this preservation method to give better storage stability to mushroom dips for 4 months at room temperature when unopened while 1 month when opened. Practical applications Present study provides preservation method for long-term storage ofAgaricus bisporus. This commonly available button mushroom is perishable in nature due to loss of evaporation and no cuticle and thus, demands for postharvest processing to improve its marketability. Vinegar dips preparation, both natural, and synthetic, thus, will help to reduce the postharvest losses and increase the shelf life stability of button mushrooms to be used all round a year. Moreover, addition of salt, black pepper, and sugar would enhance flavor attributes and sugarcane vinegar would add to the nutritional attributes improving the overall quality of the final product.