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关键词： allergenicity   atmosphere cold plasma   conformational structure   functional property   soybean protein isolate  

摘要： Currently, there has been a surge of interest in revealing the interactions between plasma and food matrices. In this study, we investigated the impacts of atmospheric cold plasma (ACP) treatment on the structural, physicochemical and allergenic characteristics of soybean protein isolate (SPI). SPI dispersions were subjected to ACP treatments at different frequencies (80 to 100 Hz) and durations (1 to 10 min) to investigate the effects of exposing conditions. Results showed that ACP induced reactive oxygen species-mediated oxidation of soy proteins, resulting in modifications in the secondary and ternary structures of SPI. As a consequence, functional properties of SPI, such as emulsifying (56 to 168%, compared with control) and foaming properties (60 to 194%) were influenced by varying degrees. In addition, under certain circumstance (120 Hz, 5 min), the IgE-binding level of SPI was decreased by up to 75%, when compared to the control. Moderate treatment yielded products with improved functionality and reduced allergenicity, while extensive exposure induced a loss of vendibility due to protein aggregation. Practical Application In this study, we demonstrated for the first time, that plasma species reacted with soybean proteins, resulting in spatial structural changes which are closely related with protein functionality and allergenicity. ACP interacts with macromolecules in aqueous systems and thus can be an alternative and promising nonthermal approach in modifying soybean proteins, whereas the exact role of different processing parameters needs to be well-elaborated.

关键词： Brine   thermal process   grill   Arapaima gigas   vacuum-packaged   sous vide   response surface methodology  

摘要： The demand for high-quality food products has promoted the study of techniques for its processing and conservation. The present research aimed to evaluate the influence of grilling pretreatment on the physical characteristics of pirarucu fillets and the heat transfer process by a computational modelling, and to optimize thesous videprocess parameters. Before and after thesous videprocess, the samples were analysed for microbiological, chemical and physical characteristics. There was no significant difference between the total experimental time of grilling and that obtained by computational modelling. Immersion in brine for 300 s in combination with grilling at 200 celcius/120 s was selected because of its water-holding capacity (%) 79.40 +/- 0.31, texture (N) 1.91 +/- 0.40 and value ofL* 74.44 +/- 0.38 in the fillets. Cooking at 60 celcius for 568.8 s were the bestsous videparameters obtained, with highest water-holding capacity (%) 93.60, texture (N) 6.24, Delta E* 7.43, and with microbiological loads below 6 log CFU/g and 7 log MPN/g in the final product. Useful information obtained from this study highlighted the brine and grill pretreatment in combination withsous videproved it is a potential solution for developing pirarucu products even at an industrial scale.

关键词： Clean label starch   Modified starch   Physical modification   Enzymatic modification  

摘要： Recently, health-conscious consumers have a tendency to avoid the use of modified starch in their food products because of reluctance regarding food additives or chemical processes. The present paper considers the characteristics and manufacturing methods of clean label starch, which is free from chemical modification. Clean label starch manufacturing is mainly dependent on starch blending, physical and enzymatic modification methods. Physical modifications include ultrasound, hydrothermal (e.g., heat-moisture treatment and annealing), pre-gelatinization (e.g., drum drying, roll drying, spray cooking, and extrusion cooking), high-pressure (high hydrostatic pressure), and pulsed electric field treatments. These physical processes allow variation of starch properties, such as morphological, thermal, rheological, and pasting properties. Enzyme treatment can change the properties of starch more dramatically. Actual use of clean label starch with such altered properties has occurred in industry and is described here. This review may provide useful information on the current status and future direction of clean label starch in the field of food science.

关键词： Dombrovska lake   Saline water   Benthic macro-invertebrate   Chironomus salinarius   Aberrations in polytene chromosomes  

摘要： This study focuses on the Dombrovska pit lake, near the city of Kalush in Ukraine, which is a former potassium salt mine filled with brine and freshwater. The water level is still increasing and as a result the salinity is decreasing. We analyzed the benthic fauna communities and the genome instability by assessing the rearrangements in the polytene chromosomes ofChironomus salinariusand the physicochemical parameters of the near-bottom water (pH, conductivity, mineralization, major ions, NO3-, NH4+, metals Cd, Pb, Cu, Mn, and Fe) and sediment (pH, organic matter and metals Cd, Pb, Cu, Zn, Mn, and Fe) at four sites. The water mineralization ranged from 17.3 to 26.2 g dm(-3)which are classified as mesohaline and polyhaline waters, respectively. The biodiversity of the benthic fauna was low, and the dominant species wasC. *** density ofC. salinariusvaried spatially and changed from 637 ind./m(2)at a depth of 5 m to 8167 ind./m(2)at a depth of 2.5 m. The genome instability was analyzed by examining the structural and functional changes in the salivary gland chromosomes ofC. salinarius. The exposure ofC. salinariusdamaged the chromosomes and the activities of key structures, such as the Balbiani ring and nucleolar organizer, were partially or completely suppressed.

关键词： Meat sauces   Native starch   Natural antioxidants   Chicken meat   Antioxidant capacity   Rheological properties  

摘要： Physicochemical properties, oxidative stability and antioxidant capacity (AC) of clean label meat-based sauces (MBSs) were investigated with reference to cold storage time (ST) and addition of phenolic extracts (PEs): green coffee bean (GCE), green tea (GTE), knotweed rhizome (KRE). All parameters determined were compared to a control sample (CS), prepared without extracts. MBSs enriched with GCE or KRE were stable during the whole ST (90 days), while the CS and samples containing GTE, showed descending trend regarding physical stability after 10 days of storage. MBSs prepared with PEs (90 days storage) demonstrated: peroxide value (PV) < 8.5 mEq O-2/kg lipids, TBARS < 5.6 mg MDA/kg lipids, carbonyl content < 4.7 nmol/mg protein, and the values were significantly (p < 0.05) smaller than those found in CS. Irrespectively of the applied measurements (ABTS, DPPH, FRAP) the values of AC (trolox equivalent, TE) decreased with ST, and regarding ABTS assay were in ranges: 0.73-0.42 mM TE (CS), 3.54-2.75 mM TE (GCE), 4.89-3.29 mM TE (GTE) and 3.86-2.25 mM TE (KRE). ANOVA revealed that rheological parameters obtained from Herschel-Bulkley ' s and Bohlin ' s models were predominantly (p < 0.001) affected by ST. After 90 days of storage, values of the desirability index were significantly (p < 0.05) higher for GCE-fortified MBS than for samples prepared with GTE and KRE. The results of this study can be useful to optimize composition of meat-based sauces containing bioactive ingredients and exhibiting desired by the consumer sensory features.

关键词： defatting treatment   deproteinization treatment   green wheat starch   multiscale structures  

摘要： Green wheat starch and its isolated A- and B-type starch granules are physically modified by deproteinization and defatting treatments. After these treatments, the morphology of the starch granules is changed as the aggregation disappears and the partial starch granule structure is disrupted. The birefringence and X-ray diffraction patterns of all the starch samples are not changed by these treatments, while the relative crystallinity of the starch samples increases on deproteinization and decreases on defatting treatment. C-13 nuclear magnetic resonance reveals that deproteinization and defatting cause an increase and decrease in the double helix content of the starch samples. These changes lead to different effects on the physicochemical properties of the various starch samples. Deproteinization increases the gelatinization temperature (T-o, T-p, T-c) and the derivative peak temperature (T-Peak) of green wheat starch and its isolated A and B-type starch granules, which is related to the increase in the relative crystallinity. Overall, the deproteinization treatment has a more obvious effect on the physiochemical and structural properties of starch granules than the defatting treatment.

关键词： carrageenan oligosaccharides   frozen storage   myofibrillar protein   shrimp mud   Xia‐   Hua  

摘要： As a popular hot-pot ingredient, Chinese-style shrimp mud (Xia-Hua) is usually transported and stored frozen. However, frozen storage leads to decreased quality of Xia-Hua products caused by the variations in physicochemical and functional properties of myofibrillar proteins (MPs). Kappa-carrageenan and its oligosaccharides are reported as antioxidants and antifreeze and can stabilize proteins in whole shrimp, but their effects on MPs in Xia-Hua remain poorly understood. Compared to the control and Na4P2O7 treatments, the physicochemical properties of MPs in kappa-carrageenan and its oligosaccharides-incorporated Xia-Hua were evaluated during 120 days of frozen storage. The results showed that cold stress increased the susceptibility of MPs to denaturation and oxidation during frozen storage. Carrageenan oligosaccharides maintained the turbidity, emulsifying activity, stability, and foaming capacity of MPs. Oxidation analysis showed that the incorporation of carrageenan oligosaccharides significantly retarded the rapid decrease of Ca2+-ATPase activity, total sulphydryl and active sulphydryl contents, and also effectively inhibited the increases of carbonyl content and surface hydrophobicity of MPs. Thermal stability results confirmed that the oligosaccharides improved the denaturation temperature and enthalpy of MPs compared to the control, Na4P2O7, and carrageenan treatments. This study suggests that kappa-carrageenan and its oligosaccharides maintain the properties of MPs in Xia-Hua during frozen storage. Practical Application The cryoprotection and antioxidant effects of carrageenan oligosaccharides on the stability of MPs in frozen shrimp mud can be used to extend the shelf-life and maintain the quality of frozen Xia-Hua products. Furthermore, it can drive the development of aquatic product health industry, improve the quality and safety of aquatic products, reduce the occurrence of public food safety incidents, and maintain social stability.

关键词： Starch   Quinoa   Amylose   Pseudocereals   Genotype   DSC  

摘要： The aim of the present study was to evaluate the physicochemical, thermal and pasting properties of the starch of six quinoa genotypes native to the northwest of Argentina. The genotypes belonging to two genotype groups, highlands and dry valley, were grown in Jujuy, Argentina. Significant differences among genotypes were observed (P < 0.05) in amylose content, swelling power, water-binding capacity, thermal and pasting properties. In the different genotypes, the starch was characterized by a typical A-type X-ray diffraction pattern, with relative crystallinity ranging between 26.1 and 28.5%. Granule-bound starch synthase (GBSS), which is the single enzyme responsible for amylose biosynthesis, was also identified, with the 67- and 58-kDa quinoa poly-peptides corresponding to the full-length and mature GBSS proteins. Studies of the pasting properties showed that the starch of the genotypes from the highlands had lower peak viscosity and lower breakdown parameter than that of the genotypes from the dry valleys. The results showed that the genotypic background and the environment influence the pasting curves. The novel findings discussed in this study constitute a starting point for research focusing on incorporating innovative technologies in the food and biomaterials industry.

关键词： Maize starch   Starch-lipid complex   Fatty acid structure   Digestion   Property  

摘要： In this study, we investigated the effects of chain length and degree of unsaturation of fatty acid (FA) on the structure, physicochemical properties, and in vitro digestibility of maize starch (MS)-FA complexes. Differential scanning calorimetry, X-ray diffraction, and Raman spectroscopy revealed that crystalline structure with V-type was formed between MS and FA. Nuclear magnetic resonance spectroscopy confirmed that the complexes with various FA structures displayed different V-type polymorphs. The thermal stability of the complexes with 14-carbon and 16-carbon FAs was better than that of other complexes. The complexes with 12-carbon (21.77%) and 14 carbon (26.31%) FAs displayed high resistant starch (RS) content, whereas those with 10-carbon FAs exhibited high slowly digestible starch (SDS) content (28.99%). Additionally, the FAs with a chain length of 10-14 carbons produced more ordered structures and showed stronger intermolecular interactions with MS than other FAs. For the 18-carbon FAs, the complexes with unsaturated FAs displayed higher RS and SDS content than those with saturated FAs. Moreover, the unsaturated FAs showed stronger intermolecular interactions with MS than the saturated FAs. These results indicated that FA structures significantly affected the structures of complexes, further affecting their physicochemical and digestive properties.

关键词： Birch outer bark   Suberin   Suberin fatty acid   Cellulose   Surface  

摘要： This paper provides evidence for the adsorption of suberin onto cellulose and illustrates the effect of suberin and suberin fatty acid (SFA) treatment on the physicochemical surface properties of the modified cellulose substrate. Suberin and SFA were extracted from the outer bark of birch (Betula pendula Roth) and characterized by Fourier transform infrared spectroscopy and gas chromatography-mass spectrometry (GC-MS). The results confirmed the extracts to comprise primarily of depolymerised suberin and SFA. The adsorption of suberin and SFA on cellulose was studied by treating the filter paper with solutions of suberin and SFA. Changes in the surface topography of the filter paper following treatment were analysed with atomic force microscopy and the effect on wettability assessed through contact angle measurement. X-ray photoelectron spectroscopy analysis showed that the cellulose substrate was evenly covered. GC-MS analysis showed which suberin monomers were preferentially adsorbed on the cellulose surfaces. Based on these results, it can be inferred that suberin and SFA have the potential for cellulose surface modification. This finding supports the view that suberin and SFA could be used to improve the interfacial properties of cellulose fibre reinforced composites. The novelty in this study is that it provides detailed information, derived though advanced experimental techniques, about the manner and mechanisms behind changes in surface physiochemical properties of cellulose obtained through suberin and SFA adsorption.