Self-Agglomeration in Fluidised Beds after Spray Drying

peer-reviewedMany powders are produced in spray-drying processes from liquid concentrates. Self-agglomeration can be performed in a fluidised bed where the spray-dried powder is agglomerated using the liquid concentrate as the binder material. This has advantages over traditional wet agglomeration in fluid beds using liquid binders (such as water or sugar solutions). These include thermal energy savings and no additional non-aqueous binder components added. The work presented has two parts. The first part is experimental, which investigated the self-agglomeration of whey protein isolate (WPI) powder as a case-study. It showed that satisfactory agglomeration was achieved with a great improvement in the wettability of the powder. The second part of the work performed thermal energy analysis to estimate the energy saving potential of self-agglomeration, and how this is influenced by binder to powder ratio and binder solids concentration. For the WPI case-study, the analysis showed there is potential for a 19% saving in thermal energy requirement for self-agglomeration in comparison to traditional agglomeration using a water binder

Application of broadband acoustic resonance dissolution spectroscopy (BARDS) to the gas release behaviour during rehydration of milk protein isolate agglomerates

peer-reviewedThe BARDS technique was applied in this study to acoustically assess the rehydration behaviour of milk protein isolate (MPI) agglomerates and to compare with regular MPI powder. The results showed that BARDS has potential to monitor the rehydration behaviour of agglomerates. The greater porosity (>70%) of agglomerated powders introduced more compressible gas into the water. The BARDS profile showed that there was faster initial gas release from the agglomerates, indicating better wetting and dispersion ability of the agglomerates with shorter tM (time of maximum gas volume in solution). At 0.10% powder addition, agglomerated MPI reached tM within 109 s, which was significantly less than the control MPI at 140 s. MPI with lactose binder (MPI-L) had a tM of 80 s at 0.10% powder addition and, larger size MPI-L had a tM of 60 s. At 0.20% and 0.30% powder addition, more time was required to wet and disperse the powders

Characterisation and improvement of the rehydration behaviour of high-protein milk powder

Milk protein isolate (MPI) has poor rehydration behaviours, particular in wetting and dissolution. The rehydration difficulty inhibited the achievement of MPI functionality. Methods were explored to solve rehydration difficulty. Agglomeration was a valid method for enhancing the wetting of dairy powder. Moreover, broadband acoustic resonance dissolution spectroscopy (BARDS) monitored gas release from powder through the alteration of speed of sound in solution. Thus, BARDS was utilised to study the gas release behaviour of agglomerated MPI, and MPI coated with emulsifiers. Meanwhile, as MPI composed mainly by casein, pH of solution affected the status of casein which possibility modify the rehydration process of MPI as well. Real-time measurement of particle size was applied to analyse the effect of pH on rehydrating MPI. Sodium carbonate, as an alkali food additive, was firstly studied at rehydrating dairy powder. However, alkalization of MPI followed by neutralization has been thoroughly investigated. Consequently, considering the effect of calcium chelation on MPI, citric acid was utilised to neutralise MPI from alkalization. Finally, the gelation behaviour of MPI was studied in a different sequence of neutralisation. Our results showed that as the porous structure modified the gas distribution in agglomerated MPI, interstitial air within agglomerates and vacuole air within agglomerates determined the gas release behaviour of agglomerated powder, while the vacuole air in primary powder particle became a crucial barrier for MPI dissolution. The BARDS profile showed that there was faster initial gas release from the agglomerates, indicating better wetting and dispersion ability of the agglomerates. The gas release of MPI during the wetting step was facilitated by lecithin and Tween 80 while the dissolution step was still poor. The wetting behaviour of MPI covered by the emulsifiers was greatly improved except for samples coated with 4% lecithin. The most instant wetting behaviour was observed when coating MPI with Tween at the larger size fractions. The swelling of the primary particle was observed in alkalization, which was ascribed to the swelling of casein micelle aggregates. This swelling of casein micelle aggregates indicates greater water penetration and loosening of the aggregate structure at higher pH, which facilitated the faster dissolution of MPI powder, especially at pH 8.4. As alkalization proved an excellent ability at the dissolution of MPI, sodium carbonate was utilised, which also showed improvement of MPI rehydration. Sodium carbonate was supposed as a calcium chelation as well to modifying the structure of casein micelle. The results showed that wettability worsened with higher sodium carbonate concentrations, due to strong films developing at the powder/water interfaces which inhibited water penetration into the MPI. However, appropriate agitation could effectively wet and disperse MPI. On the other hand, particle size and centrifugal sedimentation studies showed that increasing the sodium carbonate concentration greatly improved the dissolution ability of the MPI powder. The subsequent neutralisation process by citric acid enhanced the effects of calcium chelation due to reaction-product citrate. Besides, alkalization and neutralisation created larger colloidal particle size, which is hypothesised as being a dynamic balance between micellar casein and non-micellar casein. The sequence of neutralisation determined the process of rehydration, which in turn determine the gelation process. As for the gelation time and gel stiffness, performing alkalization firstly before neutralisation had a better result corresponding with increasing mobile casein molecule by improved rehydration, exhibiting homogeneous gel structure

Warp deformation model of polyetheretherketone composites reinforced with carbon fibers in additive manufacturing

Fused deposition modeling (FDM) provides a promising technique for the small-batch fabrication of highly customized objects. The required performance of FDM far exceeds the performances of conventional manufacturing methods. However, the temperature difference that occurs during FDM generates internal stress, which causes warp deformation and affects formed sample quality. Hence, identifying the influencing factors of warp deformation is the key to improving the forming quality of FDM samples. In this work, PEEK/short carbon fiber (CF) composites were prepared by using the FDM method, the warp deformation formula was derived, and the warp deformation mechanism was obtained. Results showed that the material linear expansion coefficient, forming chamber temperature, and forming size had considerable effects on warp deformation. Moreover, CF could improve the warp deformation of the PEEK/CF composites because of their low Poisson’s ratio and high thermal conductivity. The addition of CF could reduce the residual stress of the composites and improve warp deformation. In addition, annealing could improve the tensile and bending mechanical properties of the PEEK/CF composites. Specifically, after 3 h of heat treatment at 190 °C, the tensile and bending mechanical properties of the composites reached 10.7% and 11.6%, respectively. Crystallinity analysis revealed that the mechanical properties of the PEEK/CF composites strongly depended on their crystallinity. High cooling temperature rates were associated with low crystallinity, tensile strengths, and elastic moduli. DMA analysis showed that the addition of CF could improve the high-temperature resistance of the PEEK/CF composites as reflected by the higher glass transition temperature of the composites than that of the pure PEEK resin. Porosity analysis showed that the CF content could tailor the pore size and distribution. The study reported here provides a reference for improving the forming quality and mechanical properties of PEEK/CF composites fabricated through FDM

Identification of distinct roses suitable for future breeding by phenotypic and genotypic evaluations of 192 rose germplasms

Abstract Rose (Rosa) is a prominent ornamental plant that holds substantial economic and social significance. Roses originating from different regions exhibit intricate phenotypic and genetic characteristics, but the majority of rose genetic resources are poorly characterized. In this study, 192 genotypes of the genus Rosa were examined using 33 phenotypic traits and 10 pairs of SSR markers. Compared to wild species, both old garden and modern roses exhibited a significant level of diversity, with flower color having the highest degree of diversity and style morphology having the lowest degree of diversity. This phenomenon may be attributed to the limited utilization of wild roses due to their simpler ornamental traits and the frequent phenotypic and molecular infiltration between old garden roses and modern roses. Following a inaugural comprehensive evaluation employing principal component analysis, R. chinensis ‘Zihongxiang’, R. hybrida ‘Burgundy Iceberg’, R. hybrida ‘Conrad F. Meyer’, R. rugosa ‘Gaohong’ and R. floribunda ‘Sheherazad’ were selected as core germplasm resources for future breeding. Moreover, three tetraploid roses, namely R. hybrida ‘Midnight Blue’, R. floribunda ‘Sheherazad’, and R. hybrida ‘Couture Rose Tilia’, with significant differences in both phenotypic and molecular profiles were selected and reciprocally intercrossed. Ultimately, two populations were obtained exhibiting significant variation in flower size, annual stem color, stem pickle density, and leaf number. Furthermore, our results indicated that the traits of flower diameter, flower height, petal width, and petal number may potentially be controlled by two major-effect loci. In conclusion, this study provides novel insights into the evolutionary patterns of Rosa germplasm resources. It paves the way for identifying core genotypes that carry distinct ornamental characteristics and possess immense value for breeding novel varieties in the future

Identification and Characterization of the MADS-Box Genes and Their Contribution to Flower Organ in Carnation (Dianthus caryophyllus L.)

Dianthus is a large genus containing many species with high ornamental economic value. Extensive breeding strategies permitted an exploration of an improvement in the quality of cultivated carnation, particularly in flowers. However, little is known on the molecular mechanisms of flower development in carnation. Here, we report the identification and description of MADS-box genes in carnation (DcaMADS) with a focus on those involved in flower development and organ identity determination. In this study, 39 MADS-box genes were identified from the carnation genome and transcriptome by the phylogenetic analysis. These genes were categorized into four subgroups (30 MIKCc, two MIKC*, two Mα, and five Mγ). The MADS-box domain, gene structure, and conserved motif compositions of the carnation MADS genes were analysed. Meanwhile, the expression of DcaMADS genes were significantly different in stems, leaves, and flower buds. Further studies were carried out for exploring the expression of DcaMADS genes in individual flower organs, and some crucial DcaMADS genes correlated with their putative function were validated. Finally, a new expression pattern of DcaMADS genes in flower organs of carnation was provided: sepal (three class E genes and two class A genes), petal (two class B genes, two class E genes, and one SHORT VEGETATIVE PHASE (SVP)), stamen (two class B genes, two class E genes, and two class C), styles (two class E genes and two class C), and ovary (two class E genes, two class C, one AGAMOUS-LIKE 6 (AGL6), one SEEDSTICK (STK), one B sister, one SVP, and one Mα). This result proposes a model in floral organ identity of carnation and it may be helpful to further explore the molecular mechanism of flower organ identity in carnation

Negative Density Restricts the Coexistence and Spatial Distribution of Dominant Species in Subtropical Evergreen Broad-Leaved Forests in China

Negative densification affects the spatial distribution of species in secondary evergreen broad-leaved forests and is a key mechanism governing species coexistence. We investigated the effects of habitat heterogeneity and density on the spatial distribution of populations of dominant woody species in a secondary evergreen broad-leaved forest in Wuchaoshan using spatial univariate point pattern analyses. This 6 ha forest dynamic monitoring sample area in Hangzhou, China is a typical secondary subtropical evergreen broad-leaved forest. We found (1) a strong effect of habitat heterogeneity that led to the spatial aggregation of dominant species in the plot. Habitat heterogeneity had a strong impact on mature individuals at different life history stages and of different species on a large scale. (2) Negative density dependence (NDD) generally affected spatial distributions of most dominant species and decreased in magnitude with age class. Therefore, different species of subtropical evergreen broad-leaved forests in China have formed unique spatial structures due to their habitat preferences but are generally subjected to density-dependent effects

Isolation, structural, biological activity and application of Gleditsia species seeds galactomannans

Gleditsia fruits have been known as a valuable traditional Chinese herb for tens of centuries. Previous studies showed that the galactomannans are considered as one of the major bioactive components in Gleditsia fruits seeds (GSGs). Here, we systematically review the major studies of GSGs in recent years to promote their better understanding. The extraction methods of GSGs mainly include hot water extraction, microwave-assisted extraction, ultrasonic extraction, acid extraction, and alkali extraction. The analysis revealed that GGSs exhibited in the form of semi-flexible coils, and its molecular weight ranged from 0.018 × 103 to 2.778 × 103 KDa. GSGs are composed of various monosaccharide constituents such as mannose, galactose, glucose, and arabinose. In terms of pharmacological effects, GSGs exhibit excellent activity in antioxidation, hypoglycemic, hypolipidemic, anti-inflammation. Moreover, GSGs have excellent bioavailability, biocompatibility, and biodegradability, which make them used in food additives, food packaging, pharmaceutical field, industry and agriculture. Of cause, the shortcomings of the current research and the potential development and future research are also highlighted. We believe our work provides comprehensive knowledge and underpinnings for further research and development of GSGs.</p