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关键词： Biomonitoring   Ecological quality   Biological indicators   River ecosystem   Biotic index   Diversity index  

摘要： The main objective of the present study was to investigate the water quality of the Selendi Stream and to compare the performance of the indices. Biotic and diversity indices based on benthic macroinvertebrates have been applied using Asterics software programme. Klee's method, cluster analysis (CLUS) and principal component (PCA) analysis were applied to the physicochemical dataset. Seven sites were determined and samplings were carried out monthly. By using UPGMA analysis, similarities between the sites were clustered based on both benthic macroinvertebrates and physicochemical parameters. Pearson's based correlations were applied to the indices in order to determine the proper biotic indices. The results indicate that the BMWP Polish, BMWP Spanish, BMWP Hungarian, BMWP Greek versions and all versions of ASPT indices are more proper than FBI and BBI indices to determine the water quality of Selendi Stream.

关键词： Starch   Dioscorea   Biopolymer   Non-toxic   Tubers  

摘要： Objective: The objective of this study was to characterize the structure, physicochemical and toxicity properties of Dioscorea Pentaphylla tuber's starch. Methods: Starch was extracted from Dioscorea Pentaphylla tuber's and analyzed to determine their properties such as pH, water binding capacity, solubility, swelling power, chemical composition, thermal properties, degree of crystallinity, morphology and toxicity. Results: Results showed that more than half of Dioscorea pentaphylla starch consist of amylose (64.10 +/- 1.15%). It has gelatinization temperature started at 76.90 +/- 0.08 degrees C. This C-Type starch has a degree of crystallinity around 32.90 +/- 2.59%. The SEM image showed that Dioscorea pentaphylla has oval-shaped particles with sizes ranging from 42 to 55 mm. The toxicity test demonstrated that the starch was safe and can be classified as non-toxic. Conclusion: The physicochemical and toxicology properties of Dioscorea Pentaphylla starch recorded in this study indicate that this starch is applicable as biopolymer source for food and non-food purposes. (C) 2021 The Authors. Published by Elsevier B.V. on behalf of King Saud University.

关键词： Fruits  

摘要： Crop residues can be used in several ways, e.g processed and marketed for human consumption. The purpose of this paper is an initial approach to this few explored subject, testing two methodology of canning banana tree palm heart, treatment 1 (1% citric acid and 5% sodium chloride at the waiting liquid) and treatment 2 (200 ppm sodium bisulfite at the waiting liquid), their physical-chemical characterization and food security over time, besides sensorial analysis. Both treatments showed good values of phenolic compounds (22.56 and 14.99 mg GAE/100 g respectively) and fibers (2.96 and 2.69 g/100 g), the pH stability (below 4.5) over time and the HCN absence guarantee food security, in the acceptance and purchase intention test, obtained slightly good grades. This product is viable from a nutritional point of view, safe, promising about the palate, opening the field for further studies, in order to improve the methodology to achieve better results. Novelty impact statement This is a very complete study, covering from the physico-chemical characterization of this banana crop waste, to food security and consumer acceptance. In this context, this experiment was carried out in order to evaluate two waiting liquids, one homemade and the other with preservative commonly used in the food industry. Both treatments showed good values of phenolic compounds and fibers, associated to many health benefits. PH stability over time, before the microorganisms identified in the microbiological analyzes, and the absence of HCN guarantee food security. In the acceptance and purchase intention test, the banana tree palm heart obtained slightly good grades. Given the need to produce more food, especially in poorer regions, prove that a cultural waste, commonly discarded, can be used as a low-cost food source is very important. In addition, it provides extra income to banana producers, given that most of them are small producers.

关键词： Physicochemical properties  

摘要： A functional energy drink (FED) was prepared based on the agricultural wastes of melon seed powder (MSP) (1% and 3%) and tea stalk caffeine (TSC) (160 and 320 ppm). The beverages' physicochemical, functional, sensory, antimicrobial, and nutritional properties were measured. Results showed that increasing MSP levels increased beverage calories by 23% and beverage fiber by 53.3%. Combinations of 320 ppm of TSC with both MSP levels could show better antimicrobial properties against undesirable gram-positive bacteria. Comparison of the best FED produced in this study with two popular brands in the market showed the superiority of functional, nutritional, and safety characteristics of FEDs. The total phenolic compounds (TPC) and antioxidant capacity in the best drink produced were 1.56 mg gallic acid/mg and 48.72%, respectively. The sensory properties increased by increasing MSP and TSC, indicating good overall acceptance. In general, by MSP and TSC addition, a desirable FED can be achieved. Practical applications The food processing industry, along with increased awareness of nutrition among consumers, is completing a cheaper source of nutrients to finally become functional foods. Our results showed that the appropriate combination of agricultural waste to produce a FED has better quality and activity compared to those on the market.

关键词： Protein concentration   pH   Interfacial properties   Emulsifying properties   NaCl concentration  

摘要： The physicochemical characteristics, interfacial, and emulsifying properties of ?-conglycinin (7S) at various protein concentrations (c), pH values (pH), and NaCl concentrations (NaCl) were characterized. The increase in c did not change the z-average diameters, solubility, and hydrophobicity but remarkably increased the net charges of 7S. The interfacial properties and emulsifying efficiency of 7S exhibited a dramatic dependence on the increase in c. Thus, the increased electrostatic repulsions facilitating the structural rearrangement and enough protein adsorbing onto the oil droplets? interfaces were the requirements for good emulsifying efficiency. 7S at pH 3 and 8 exhibited smaller z-average diameters, higher net charges, and solubility than that at pH 5, positively affecting their adsorption and the formation of viscoelastic layers. Thus, 7S at pH 3 and 8 showed better emulsifying efficiency. The increased NaCl did not change the z-average diameters, solubility, and hydrophobicity but decreased Zeta potentials of 7S due to electrostatic screening effects. Also, the increased NaCl improved interfacial adsorption kinetics but less viscoelastic interfacial layers of 7S. It suggested that low net charges decreased the electrostatic barrier for adsorption but did not benefit the intermolecular interaction of 7S at the interface. The emulsions aggregation at a high ionic strength indicated a negative effect on emulsifying activity.

关键词： Antioxidants  

摘要： The objective of this study was to compare drinkable yogurts added with purple cactus pear powder without ultrasonication (WY) and ultrasonicated (UY);with formulated yogurt with synthetic dyes (DY) and commercial saborized yogurt evaluating pH, titratable acidity, water holding capacity, viscosity, color, microbiology and in vitro bioaccessibility of antioxidants. The WY and UY showed an increase in functional properties, high ascorbic acid, and phenolic content (129.83 and 57.27 mg AAE/100 ml;26.64 and 22.87 mg GAE/100 ml, respectively). The UY increased the antioxidant activity measured by ABTS (6.41 +/- 0.11 mg VCEAC/100 ml) and DPPH (38.38 +/- 0.92 mu M TE/100 ml) in comparison to WY. After bioaccessibility assay, the UY had high phenolic content and antioxidant activity by ABTS, just below DY which presented the major content with respect to the other samples. The ultrasonicated purple cactus pear powder addition could be an alternative to drinkable yogurt with bioaccessible antioxidants. Practical applications The benefits of yogurt make it a popular food with high consumption by its nutritional aspect, mainly if the product has natural additives that provide antioxidant compounds related to beneficial health effects, such as heart disease, diabetes, cancer, and among others. The different raw matter of purple cactus pear juice powder could provide an intense color as a natural additive to dairy products such as yogurt, which can be an alternative to synthetic additives since they play an important role in the quality of the product and consumer acceptance. In addition, the yogurt added with purple cactus pear juice powder also provides antioxidant content and high bioaccessibility, with light changes in their physicochemical characteristics.

关键词： Microbial cellulose   Kombucha culture   FIB-SEM   FT-IR   TGA   XRD  

摘要： Bacterial cellulose (BC) is a natural biopolymer, used in biomedical, food, paper, electronics and other industrial processes. The objective of this research was to improve the productivity of cellulose by using a new kombucha consortium (Komagataeibacter saccharivorans LN886705, Brettanomyces bruxellensis MH393498 and Brettanomyces anomalus KY103303) with a low-cost nitrogen source (black tea). Accordingly, BC can be highly produced (18.68 g/L BC) in optimized media (containing 1% black tea and 6% glucose, pH 6) at 30 degrees C, for 10 days under static cultivation. Results demonstrated that cellulose production enhanced 4.06 times in optimized medium when compared with Hestrin-Schramm medium (4.59 g/L BC) with a 29.74% cost reduction. Characterization of obtained cellulose was performed by using Focussed Ion Beam Scanning Electron Microscopy (FIB-SEM),Fouirer Transform Infrared (FT-IR) Spectrometer, Thermogravimetric Analysis (TGA-DSC) and X-Ray Diffraction (XRD). Cellulose fibrils showed a typical porous, cellulose type I structure and exhibits high thermal stability with a total weight loss of 76%. Results confirmed that, it was possible to obtain high value cellulose with excellent physicochemical properties and cost-reduction by using low-cost nitrogen source.

关键词： Phenols  

摘要： Four different levels (0, 1.00, 2.50, and 5.00%) of oat flour (OF) were used to produce processed cheese to assess their impact on the antioxidant activity, mineral contents, phenol contents, physicochemical, microstructure, and sensory properties of the resulting OF processed cheese. Dry matter and pH values of processed cheese increased with increasing OF. Meltability and oil separation of cheese decreased significantly (p <= .05) but increased during storage. The functionality of processed cheese increased with the addition of OF and samples with OF exhibited significantly (p <= .05) high levels of phenols, antioxidant activity, and mineral contents. Microstructure of processed cheese indicated that the samples with added OF had a dense protein network with lower interfaces, which affect the texture of cheese compared to control. In conclusion, the added proportions 1.00 or 2.50% of oat flour in processed cheese could be successfully used to improve functionality, health benefits and nutritional quality. Novelty impact statement Processed cheese was produced using oat flour at level 1.00 or 2.50%. The study found that oat flour increased the functionality of processed cheese in terms of phenol contents, antioxidant activity and other micronutrients. Processed cheese with added oat flour could be served for consumers as a nutritious functional product with numerous health benefits.

ISBN: (纸本)9787122393883

关键词： D   roosii rhizome   physicochemical properties   starch  

摘要： Drynaria roosii, a traditional Chinese medicine, is a large epiphytic fern that belongs to the family Polypodiaceae. It is a novel starch plant resource with commercial value. The physicochemical properties of starch isolated from the rhizome of D. roosii are investigated for the first time and compared with those of other commercial starches, including Pteridium aquilinum (L.) Kuhn, Triticum aestivum L., and Manihot esculenta Crantz. The rhizome of D. roosii contains total starch and apparent amylose contents of 17.26% and 30.01%, respectively. The starch from D. roosii has a unimodal distribution, large particles with elliptical or spherical to irregular shape, C-B-type crystal pattern, and no single-helix structure. The swelling power, solubility, pasting temperature, and breakdown and setback viscosities are the lowest, and the resistant starch contents in native, gelatinized, and retrograded starches are the highest. The amylopectin of the starch from D. roosii exhibits lower proportions of short chains with DP 6-24, higher proportions of longer chains with DP 25-100, and average chain length than those of the other three starches. These findings have great significance to broaden the understanding of Polypodiaceae starch, which has great potential for utilization in food industries.