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关键词： Acrylamide   chips   colour   cooking method   lupin flour   p‐   anisidine   peroxide values   physico‐   chemical properties  

摘要： Development of novel snack foods is an important area of research, and different ingredients are being tested to develop and process new formulations. In this study, lupin chips prepared using different formulations (hulled lupin, whole lupin, wheat and corn flours) were cooked using baking and frying, and changes in the sensory and colour parameters, acrylamide contents, fat absorption, peroxide number and p-anisidine values of the final products were studied. Lupin flour significantly changed p-anisidine value of chips. Addition of lupin flour and cooking methods affected the colour, fat absorption and peroxide values. Significant differences in chemical properties of chips made from whole and hulled lupin flours were also observed. Acrylamide was not detected in all the formulations studied. The lupin chips have increased brightness (L*), no acrylamides, reduced peroxide and p-anisidine values and acceptable sensory quality;hence, this ingredient is recommendable for use in snack foods.

关键词： Propolis   Physico-chemical and techno-functional   properties   Textural profile analysis   DSC   PCA  

摘要： Objective: The present study assessed physico-chemical, techno-functional, thermal and textural characteristics of propolis samples (n = 30) collected from four Northern zones of India. Methods: The propolis samples were analyzed according to the Association of Official Analytical Chemists (AOAC) official protocols for their ash, moisture, and protein content. Soxtech, Fiber tech, Hunter LAB Colorimeter, ***2i Texture Analyzer, Thermo gravimetric Analyzer, Discovery DSC 25 have been used to assess the crude fat, fibre content, colour, texture and thermal properties, respectively. Results and conclusions: Physico-chemical properties of propolis differed significantly (p < 0.05) and reportedthe highest balsam content (47.66%), protein (9.41%) and wax content (22.9%) in Punjab propolis (PP) where as the moisture content and water activity ranged from 4.89 to 7.37% and 0.73-0.81, respectively in propolis samples. Regarding techno-functional properties, PP had highest oil holding capacity (1.09-1.90 g/g), foaming capacity (11.08-17.03%), foam stability (67.3-75.43%), emulsifying activity (4.18-7.62%), and emulsion stability (3.24-4.77%). The positive a* and b* values of colour in this investigation indicated that the samples from all four zones lied in reddish yellowish areas of LAB colour space and relatively dull or gray as indicated by chroma values. Results of texture profile analysis demonstrated that all propolis samples were hard, cohesive, chewy and showed resilience. Differential scanning calorimetry predicted semi-crystalline behaviours of all samples. Three principal components, accounting for 98.95% variation were abstracted from fourteen physiochemical, seven techno-functional, seven textural and four thermal variables. Further, hierarchical cluster analysis successfully classified the propolis samples into four zones. (c) 2021 The Author(s). Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND

关键词： Physicochemical properties  

摘要： Red millet is a novel raw material for brewing Chinese rice wine. The physicochemical and structural properties of red millet (R1) were compared with those of five other brewing materials during pretreatment (soaking and steaming). Significant differences in physicochemical characteristics were found among raw grain varieties (p < .05). R1 had the highest protein content (18.36/100 g). The total acid and amino nitrogen contents of all grains showed a fluctuating upward trend during the soaking process. The reduction in setback viscosity of most grains after soaking indicated that soaking treatment slowed the retrogradation of starch. The grains changed into a gelatinized form with expanded pores after steaming. Further brewing might be beneficial due to the high acidity of soaking water (12.77 g/L), low setback value (336.50 cp), and large pore structure of R1 after pretreatment. Novelty impact statement In this study, some new findings were as follows: (1) the protein and fat content of red millet was the most outstanding;(2) red millet soaked water showed the highest total acid and amino nitrogen contents;(3) during steaming, grain morphological transformed into expanded porous structure. These results would improve our comprehending of the raw material characteristics of red millet, thereby providing theoretical guidance for the production and brewing of red millet wine.

关键词： Biochar   Pyrolysis   Physico-chemical characteristics   Distilled spirit lees   Tobacco fine   Chinese medicine waste  

摘要： This paper investigates the physico-chemical characteristics of biochar from three specific waste materials including distilled spirit lees (DSL), tobacco fine (TF) and Chinese medicine residue (CMR) prepared by pyrolysis at 450 degrees C, 550 degrees C and 650 degrees C. All produced biochars were further analyzed for their ability to adsorb ammonium with initial concentrations of 0 500 mg.L-1. Results showed that all biochars mainly consist of C and O, and possess highly-porous morphology features with pore size of 2.029-6.731 nm. With same feedstock, carbonized DSL, TF and CMR at 650 degrees C has largest specific surface area of 6.293 m(2) g(-1), 57.485 m(2) g(-1) and 14.668 m(2) g(-1) respectively. The positions of the infrared peaks of biochar derived from same feedstock are similar, but the intensity of some peaks has changed. With same feedstock, DSL450/550, TF650, and CMR450 biochar showed the best performance for ammonium removal with an adsorption capacity of 10.3199-11.8906, 10.4603-13.3511 and 23.2558-24.1546 mg g(-1) respectively. The adsorption progress of ammonium by DSL biochar could be well described by both Freundlich and Langmuir adsorption isotherm, while the progress of TF biochar and CMR biochar was best described by Langmuir and Freundlich adsorption isotherm respectively. The fitted results indicate that the adsorption process of NH4+-N by both DSL biochar and TF biochar are uniform monolayer adsorption on the surface, but the adsorption of CMR biochar is mainly in the heterogeneous adsorption mode of multi-molecular layers. In sum, the experiment that was performed as well as the parameters used proved to be feasible for DSL biochar, TF biochar and CMR biochar production as adsorbing medium.

关键词： Delivery system   Functional oil   Antioxidant   Encapsulation   Stress conditions   Long-term storage   Chemical stability   Oxidation  

摘要： In this study, pomegranate seed oil (PSO) nanoemulsions loading different amounts of alpha-tocopherol (0-40%) were produced. The nanoemulsions were fabricated by ultra-sonication method and the influence of thermal treatment (20-90 degrees C), pH (2-8) and ionic strength (0-500 mM NaCl) were investigated on physicochemical properties of all treatments. Moreover, the oxidative stability and alpha-tocopherol degradation were also assessed on optimal enriched nanoemulsion formulation during 50-day storage. The droplet diameter, viscosity, antioxidant activity, encapsulation efficiency and loading capacity of optimal formulation were 37.5 nm, 514 cp, 92%, 3.45% and 92.5%, respectively. The peroxide value changed in the range of 4.5-5.3 and 6.7-10.5 meq O-2/kg in loaded and unloaded nanoemulsions, respectively. Transmission electron microscopy demonstrated spherical morphology of nanoemulsion droplets with diameter average of 40 nm. This study suggested that PSO nanoemulsion loading alpha-tocopheml could be introduced as delivery system with favorable features under severe environmental conditions.

关键词： Chestnut honey   Highland honey   Melissopalynological analysis   Physio-chemical analysis   Trace element  

摘要： The aim of this study was to determine the physicochemical parameter changes, aroma, melissopalynological properties, and heavy metal content of honey produced from different types of flora (chestnut and highland) in the Senoz Valley. For this purpose, the distribution of beehives at different elevation levels in the research area was determined by a layered random sampling method. Some characteristics of the honey samples were analyzed by standard laboratory methods. The highest average color (L and b) and the glucose, sucrose, Brix, Cd, Pb, Ni, Zn, and Cr values were found in the highland honeys;the highest color (a) and fructose, F/G ratio, proline, pH, conductivity, Fe, Cu, Al, and Mn values were found in the chestnut honeys. The difference between highland and chestnut honeys was statistically significant in terms of color (L and a), F/G ratio, proline, pH, electrical conductivity, Pb, Cu, and Mn. A total of 146 aromatic components were isolated in the chestnut and highland honeys.

关键词： Yellow pea   Plant-based ingredients   Starch damage   Aromatic profile   Untargeted metabolomic approaches  

摘要： Yellow pea (Pisum sativum L., YP) grain is generally milled into flour for further processing or direct consumption. However, the comprehensive relationship between milling configurations and YP flour properties remains unclear. The aim of this study is to investigate the effect of configurations (screen aperture size and rotor speed) of ultracentrifugal mill on the physicochemical properties and aromatic profiles of YP flours. Starch damage, morphology, particle size distribution, pasting, thermal property, and aromatic profiles of YP flours were studied. Results show that starch damage increased significantly as the screen aperture size decreased. The YP flour produced with a 500 mu m aperture screen had the most stable pasting and thermal properties. With untargeted metabolomic approaches, 2-ethyl-1-hexanol could potentially be applied as an aroma maker to distinguish if an excessive milling or inappropriate configurations of ultracentrifugal mill are applied. This work has furnished fundamentals for the milling and application of YP flour.

关键词： omega-3 PUFAs   Nanoliposome   Surface decoration   Chitosan   Gelatin   Physicochemical stability  

摘要： To enhance the physicochemical stability of omega-3 PUFAs concentrates from fish oil, biopolymer coating based on chitosan (CH) and gelatin (GE) deposited on the surface of nanoliposomes (NLs) has been synthesized and characterized. The mean particle size of surface-decorated nanoliposomes (SDNLs) containing omega-3 PUFAs concentrates was found to be in the range of 209.5-454.3 nm. Scanning and transmission electron microscopy revealed the spherical shape and smooth surface of the nanovesicles. Fourier-transform infrared spectroscopy and X-ray diffraction observations confirmed that the NLs have been successfully coated by biopolymeric blends. The highest entrapment efficiency of 81.6% was obtained in polymer-stabilized NLs with a concentration ratio of 0.3:0.1 (CH:GE). Differential scanning calorimetry results revealed enhanced thermal stability of vesicles after polymeric blend desorption. Finally, the oxidative stability assays demonstrated that the omega-3 PUFAs concentrates entrapped in SDNLs was protected against oxidation in comparison to the free omega-3 PUFAs concentrates.

关键词： Potato   Solanum tuberosum L.   Nutritional analysis   Physicochemical characterization   Linear discriminant analysis   Biodiversity   Food security  

摘要： Fifty potato genotypes from twenty-four different countries of origin, four different flesh colours (yellow, purple, red and marble) and different cultivation types (Andean accessions, landraces, breeder lines and cultivated varieties) were studied in terms of their nutritional and physicochemical characteristics. In general, cultivated varieties and breeder lines showed the highest similarity (slight differences only in some particular fatty acids distributions: C10:0, C12:0 and C22:0) concerning the physicochemical parameters assayed in this work, independently of the geographical origin or tuber flesh colour of these genotypes. Nonetheless, some of the studied landraces and Andean accessions proved to be similar enough to be considered as genotypes with good potential for commercial cultivation. These results can contribute to the supply of new potato genotypes into sustainable farming systems, supporting the protection of potato biodiversity, particularly Andean accessions, landraces and coloured genotypes (red or purple flesh) which are not widely cultivated so far.

关键词： Myofibrillar proteins   TGase   EGCG   Double-crosslinking   Molecular docking  

摘要： The aim of this study was to determine the influence and mechanism of combining EGCG with TGase on properties of myofibrillar protein (MP) gel. A double-crosslinked effect was observed when EGCG and TGase were added into MP gel. Breaking force, deformation, water holding capacity and hardness of double-crosslinked MP gel increased by 25.3 +/- 3.0 g, 0.5 +/- 0.3 mm, 1.76 +/- 0.4% and 34.11 +/- 2.56 g, compared with those of TGase induced gel. Light microscopy and low-field nuclear magnetic resonance results indicated with EGCG content increasing, pores and structure of double-crosslinked gels became smaller and denser, T-22 decreased from 266.162 ms to 252.845 ms and its proportion increased from 94.103% to 96.956%. Molecular docking illustrated covalent and non-covalent interactions between EGCG and myosin heavy chain II A, and confirmed TGase catalytic mechanism with myosin heavy chain II A as substrate. Therefore the mixture of EGCG and TGase could be used as novel cross-linker in surimi.