Lower Melt Rates Research Articles

Geochemistry and Petrology of post-Archean dolerite intrusions in the Elogo Complex in the Ivindo Basement northwest of the Congo Craton

Geochemical and tectono-metamorphic study of post-Archean dolerite intrusions is carried out to reconstruct the petrogenesis and geodynamics of post-Archean intrusive mag- matism in the Congo Craton. Dolerites and hornblendites of the Elogo complex are characterized by a low-pressure greenschist metamorphism controlled by brittle micro tectonics and are metaluminous (A/NK: 4.47 and 7.84; A/CNK: 1.02 and 1.37) with a dominant tholeiitic affinity and affected by hydrothermal alteration (LOI = 1.13 – 8.7 %). LREE and Th enrichment, negative Nb and Ti anomaly, low Nb/Th, (Nb/La)PM < 1, Ti/Yb, Ce/La < 0.85, Nb/La < 1, and Ta/Th < 1 ratios, and high (La/Yb)n > 1 and (La/Sm)n > 1 define the dolerites geochemical signature as crustal contaminated. Al2O3/TiO2 (12.17 to 19.65), CaO/Al2O3 (0.60 to 0.78), (Gb/Yb)PM > 1 ( 1.15 to 1.32), and (Tb/Yb)n (1.13 to 1.29) ratios associated with the lack of HREE fractionation (Yb = 11.24 to 18. 01 ppm) characterize a shallow (1073.03 to 1189.92°c) spinel lherzolite-type mantle source with low melt rate (f = 10 to 20%), outside the garnet stability field [(Th/Ta)n < 1]. The negative Nb, Ti, Zr, Rb, and Ba anomalies, positive Hf, Th, and U anomalies, the moderate Cs and LREE (La and Ce) enrichment, and the REE fractionation [(La/Yb) n >1], associated with the high Ta contents, define an extensive intracratonic rift-type setting. The vein rocks originate from an asthe- nospheric uplift marked by lithospheric thinning in a Mezo-Neoproterozoic rift system that dislocated the Congo Craton inducing the genesis of the tholeiitic dolerites (1167 Ma and 850 Ma) of Nola in RCA and Yokadouma in Cameroon.

Rift propagation signals the last act of the Thwaites Eastern Ice Shelf despite low basal melt rates

Abstract Rift propagation, rather than basal melt, drives the destabilization and disintegration of the Thwaites Eastern Ice Shelf. Since 2016, rifts have episodically advanced throughout the central ice-shelf area, with rapid propagation events occurring during austral spring. The ice shelf's speed has increased by ~70% during this period, transitioning from a rate of 1.65 m d−1 in 2019 to 2.85 m d−1 by early 2023 in the central area. The increase in longitudinal strain rates near the grounding zone has led to full-thickness rifts and melange-filled gaps since 2020. A recent sea-ice break out has accelerated retreat at the western calving front, effectively separating the ice shelf from what remained of its northwestern pinning point. Meanwhile, a distributed set of phase-sensitive radar measurements indicates that the basal melting rate is generally small, likely due to a widespread robust ocean stratification beneath the ice–ocean interface that suppresses basal melt despite the presence of substantial oceanic heat at depth. These observations in combination with damage modeling show that, while ocean forcing is responsible for triggering the current West Antarctic ice retreat, the Thwaites Eastern Ice Shelf is experiencing dynamic feedbacks over decadal timescales that are driving ice-shelf disintegration, now independent of basal melt.

Physicochemical property characterization, amino acid profiling and sensory evaluation of plant-based ice cream incorporated with soy, pea and milk proteins

This study examined the effects of incorporating milk protein concentrate (MPC), pea or soy proteins isolates (PPI and SPI) on the physicochemical, sensorial properties, and amino acid composition of ice creams containing 7% protein, in comparison to dairy ice cream as a reference. As protein ingredients, PPI exhibited higher water and oil holding capacity but lower surface hydrophobicity than SPI and MPC. Viscosity of the mixes were proportional to the firmness of ice cream, and both were highest with use of PPI. MPC ice cream had most similar physical and sensory properties to reference. PPI and SPI ice cream mixes showed higher extent of fat coalescence than MPC and reference. PPI and SPI conferred structural stability to ice cream with lower melting rate and better shape retention, and ability to delay ice recrystallization during temperature flocculation as compared with SMP and MPC. Confocal laser scanning microscope images indicated that higher extent of protein aggregation and more air cells were found in PPI ice cream. Sensory and amino acid profile results revealed that PPI and SPI ice creams were inferior in taste, texture, and essential amino acids like methionine. This study offers insights for the development of high protein frozen desserts.

Physicochemical and microbiological characteristics of kefir ice cream with the addition of bengkuang (Pachyrhizus erosus (L.)) starch

The technology for fermenting milk kefir and the development in processing kefir ice cream is crucial to produce superior food products that support health. The addition of prebiotics from bengkuang (Pachyrhizus erosus (L.)) starch in making ice cream is the main purpose of improving the quality of kefir ice cream. This research purposed to determine the physicochemical (moisture, ash, protein, fat, phenolics, and DPPH for free radical scavenging activity) and microbiological (lactic acid bacteria, yeast, Lactobacillus, Lactococcus, Leuconostoc) characteristics of kefir ice cream after the addition of 3, 5, 7 and 9% (w/w) bengkuang starch. This ice cream used fresh cow’s milk, skim milk, kefir, granulated sugar, whipped cream, CMC (Carboxy Methyl Cellulose), egg yolks, and varying amounts of bengkuang starch. The research showed that the best formulation for all physicochemical and microbiological characteristics was the kefir ice cream added with 9% (w/w) bengkuang starch. This product had stable viability of probiotic microbes (both lactic acid bacteria and yeast), the same protein value as the control, low fat, pH suitable for probiotics, high total phenolic content and DPPH value, and low melting rate even though the overrun value was lower compared to controls. The synergistic combination of bengkuang starch and probiotics from kefir in making ice cream has the potential to produce nutritious functional foods that are beneficial for human health.

Thermally treated peanut oil bodies as a fat replacer for ice cream: Physicochemical and rheological properties

This study investigates the potential use of peanut oil bodies as a fat replacer in ice cream. We explored the effects of different treatments, fresh (FOB), heated (HOB), and roasted (ROB) peanut oil bodies on ice cream preparation. Heat treatment altered the intrinsic protein profile on the oil bodies' surface, subsequently influencing the ice cream's properties. Notably, heat treatment increases the oil bodies' size and the absolute value of ζ-potential. The rheological analysis provided information about void volumes, indicating easier air incorporation during whipping for ROB (72 to 300 nm) than FOB (107 to 55 nm). ROB ice cream displays a high overrun and a lower melting rate compared to FOB ice cream. Moreover, thermal treatment reduces the beany flavors, n-hexanal, and 2-pentenylfuran. Overall, this study reveals peanut oil bodies as a promising platform for rational design of fat-substituted plant-based ice creams.

Impact of soy protein dispersibility on the structural and sensory properties of fat-free ice cream

Soy protein can be an effective fat replacer in ice cream due to its contribution to the viscosity and foaming ability. In this study, we investigated the individual effect of soy protein particle size and mix viscosity on the physical, rheological, tribological and sensory properties of fat-free ice cream. Particle size was varied by homogenization and subsequent separation of the dispersible and non-dispersible fractions. Three series of ice cream mixes were made in which (i) particle size and viscosity were varied, (ii) particle size was varied with a constant viscosity, and (iii) the ratio between the dispersible and non-dispersible protein fractions, particle size and viscosity were varied. The results showed that dispersible protein particles (0.25 μm) led to lower hardness and higher scoopability as their presence was related to increased overrun and reduced non-air thickness between the air cells. In comparison, large non-dispersible particles (3.8–145 μm) enhanced the melting resistance and stability of ice cream by forming a network in the serum phase. Therefore, the size of the protein particles determined their functionality in ice cream. Based on sensory evaluation, samples with a protein particle size of approximately 4 μm showed a relatively denser texture, a lower melting rate and better lubrication behavior (lower friction), as well as a sensory profile similar to that of full-fat ice cream. This study indicates that both textural and sensory properties of fat-free ice cream can be improved by manipulating the size of plant proteins and mix viscosity.

A Regime Shift on Weddell Sea Continental Shelves with Local and Remote Physical and Biogeochemical Implications is Avoidable in a 2°C Scenario

Abstract Tipping points in the Earth system describe critical thresholds beyond which a single component, part of the system, or the system as a whole changes from one stable state to another. In the present-day Southern Ocean, the Weddell Sea constitutes an important dense-water formation site, associated with efficient deep-ocean carbon and oxygen transfer and low ice-shelf basal melt rates. Here, a regime shift will occur when continental shelves are continuously flushed with warm, oxygen-poor offshore waters from intermediate depth, leading to less efficient deep-ocean carbon and oxygen transfer and higher ice-shelf basal melt rates. We use a global ocean–biogeochemistry model including ice-shelf cavities and an eddy-permitting grid in the southern Weddell Sea to address the susceptibility of this region to such a system change for four twenty-first-century emission scenarios. Assessing the projected changes in shelf–open-ocean density gradients, bottom-water properties, and on-shelf heat transport, our results indicate that the Weddell Sea undergoes a regime shift by 2100 in the highest-emission scenario, SSP5–8.5, but not yet in the lower-emission scenarios. The regime shift is imminent by 2100 in the scenarios SSP3–7.0 and SSP2–4.5, but avoidable under the lowest-emission scenario SSP1–2.6. While shelf-bottom waters freshen and acidify everywhere, bottom waters in the Filchner Trough undergo accelerated warming and deoxygenation following the system change, with implications for local ecosystems and ice-shelf basal melt. Additionally, deep-ocean carbon and oxygen transfer decline, implying that the local changes ultimately affect ocean circulation, climate, and ecosystems globally.

Coastal Polynyas Enable Transitions Between High and Low West Antarctic Ice Shelf Melt Rates

AbstractMelt rates of West Antarctic ice shelves in the Amundsen Sea track large decadal variations in the volume of warm water at their outlets. This variability is generally attributed to wind‐driven variations in warm water transport toward ice shelves. Inspired by conceptual representations of the global overturning circulation, we introduce a simple model for the evolution of the thermocline, which caps the warm water layer at the ice‐shelf front. This model demonstrates that interannual variations in coastal polynya buoyancy forcing can generate large decadal‐scale thermocline depth variations, even when the supply of warm water from the shelf‐break is fixed. The modeled variability involves transitions between bistable high and low melt regimes, enabled by feedbacks between basal melt rates and ice front stratification strength. Our simple model captures observed variations in near‐coast thermocline depth and stratification strength, and poses an alternative mechanism for warm water volume changes to wind‐driven theories.

Global Climate Impacts of Greenland and Antarctic Meltwater: A Comparative Study

Abstract Both the Greenland and Antarctic ice sheets have been melting at an accelerating rate over recent decades. Meltwater from Greenland might be expected to initiate a climate response that is distinct, and perhaps different from, that associated with Antarctic meltwater. Which one might elicit a greater climate response, and what mechanisms are involved? To explore these questions, we apply climate response functions (CRFs) to guide a series of meltwater-perturbation experiments using a fully coupled climate model. In both hemispheres, meltwater drives atmospheric cooling, sea ice expansion, and strengthened Hadley and Ferrel cells. Greenland meltwater induces a slowdown of the Atlantic meridional overturning circulation (AMOC) and a cooling of the subsurface ocean in the northern high latitudes. Antarctic meltwater, instead, induces a slowdown of the Antarctic Bottom Water formation and a warming of the subsurface ocean around Antarctica. For melt rates up to 2000 Gt yr−1, the climate response is rather linear. However, as melt rates increase to 5000 Gt yr−1, the climate response becomes nonlinear. Due to a collapsed AMOC, the climate response is superlinear at high Greenland melt rates. Instead, the climate response is sublinear at high Antarctic melt rates, due to the halting of the northward expansion of Antarctic sea ice by warm surface waters. Finally, in the linear limit, we use CRFs and linear convolution theory to make projections of important climate parameters in response to meltwater scenarios, which suggest that Antarctic meltwater will become a major driver of climate change, dominating that of Greenland meltwater, as the current century proceeds. Significance Statement Melting of the Greenland and Antarctic ice sheets is one of the most uncertain potential contributors to future climate change. In this study, we address the comparative role of Greenland and Antarctic meltwater in the climate system and explore the differing mechanisms at work in each hemisphere. We find that the climate response is linear for low melt rates but becomes nonlinear for high melt rates. As the century proceeds, we speculate that Antarctic meltwater will increasingly dominate that of Greenland meltwater, leading to atmospheric cooling, Antarctic sea ice expansion, and contraction and warming of the Antarctic Bottom Water. Greenland meltwater will, instead, affect smaller changes in the Northern Hemisphere.

Exploring ice sheet model sensitivity to ocean thermal forcing and basal sliding using the Community Ice Sheet Model (CISM)

Abstract. Multi-meter sea level rise (SLR) is thought to be possible within the next few centuries, with most of the uncertainty originating from the Antarctic land ice contribution. One source of uncertainty relates to the ice sheet model initialization. Since ice sheets have a long response time (compared to other Earth system components such as the atmosphere), ice sheet model initialization methods can have significant impacts on how the ice sheet responds to future forcings. To assess this, we generated 25 different ice sheet spin-ups, using the Community Ice Sheet Model (CISM) at a 4 km resolution. During each spin-up, we varied two key parameters known to impact the sensitivity of the ice sheet to future forcing: one related to the sensitivity of the ice shelf melt rate to ocean thermal forcing (TF) and the other related to the basal friction. The spin-ups all nudge toward observed thickness and enforce a no-advance calving criterion, such that all final spin-up states resemble observations but differ in their melt and friction parameter settings. Each spin-up was then forced with future ocean thermal forcings from 13 different CMIP6 models under the Shared Socioeconomic Pathway (SSP)5-8.5 emissions scenario and modern climatological surface mass balance data. Our results show that the effects of the ice sheet and ocean parameter settings used during the spin-up are capable of impacting multi-century future SLR predictions by as much as 2 m. By the end of this century, the effects of these choices are more modest, but still significant, with differences of up to 0.2 m of SLR. We have identified a combined ocean and ice parameter space that leads to widespread mass loss within 500 years (low friction and high melt rate sensitivity). To explore temperature thresholds, we also ran a synthetically forced CISM ensemble that is focused on the Amundsen region only. Given certain ocean and ice parameter choices, Amundsen mass loss can be triggered with thermal forcing anomalies between 1.5 and 2 ∘C relative to the spin-up. Our results emphasize the critical importance of considering ice sheet and ocean parameter choices during spin-up for SLR predictions and suggest the importance of including glacial isostatic adjustment in ice sheet simulations.

Numerical Investigation on the Electroslag Remelting of High Carbon Martensitic Stainless Steels

Control of solidification structure and segregation is crucial to improve the service performance of high carbon martensitic stainless steels. Design of the electroslag remelting (ESR) process based on the essential parameters of melting rate, filling ratio, and slag thickness is a precondition to achieve optimal control of solidification structure and segregation of the steels. However, there is still a lack of coupled works giving deep insight into the overall effect of the parameters on the expected control. With this background, a 2D numerical model was established to probe into the effect of process parameters. The results showed that: (1) With the increase of melting rate from 90 kg/h to 180 kg/h, the molten metal pool depth increased by about 4 cm. Meanwhile, the center LST, PDAS, and SDAS increased by about 450 s, 100 μm, and 12 μm. The segregation index of C and Cr increased by about 0.15 and 0.09. (2) As the filling ratio increased from 0.16 to 0.43, the depth of the metal pool decreased by about 4.5 cm, LST and SDAS received a slight increase of about 41 s and less than 5 μm, but PDAS had little change. The segregation index of C had an increase of about 0.03, but the segregation index of Cr demonstrated tiny changes. (3) As the slag thickness increased from 0.08 to 0.14 m, the metal pool depth presented a first increase of about 1 cm and then a slight decrease. The center LST, PDAS, and SDAS first increased by 148 s, 30 μm, and 4 μm and then decreased slightly. The changes of the segregation index of C and Cr presented a similar tendency than that of LST, but the changes are extremely small. (4) A low melting rate less than 120 kg/h, a filling ratio of about 0.23–0.33, and a slag thickness of 0.08–0.10 m were appropriate to obtain good performance for ESR of high carbon stainless steels in this study.

Physicochemical and Rheology Properties of Ice Cream Prepared from Sunflower Oil and Virgin Coconut Oil

In the last decade, increasing trends towards the consumption of healthier foods have forced processors of high-fat products (ice cream) to shift their formulations to higher proportions of unsaturated or “healthier” fats. Vegetable oils such as sunflower oil and VCO can be used as a substitute for milk fat, milk solids not fat (skim milk powder), sweeteners, stabilizers and emulsifiers, and mineral water in making ice cream. A study was carried out to determine the effects of the use of the ratio of sunflower oil: virgin coconut oil with palm fruit as a stabilizer in the production of ice cream on physicochemical properties (pH, proximate, overrun, viscosity, and melting rate). The use of palm fruit is based on the content of galactomannan in palm fruit. Premium ice cream with five different ratios of SO and VCO (15:0), (10:5), (7.5:7.5), (5:10), (15:0). The ice cream production involves mixing, pasteurization, homogenization, aging, and freezing. The physicochemical result shows ice cream sample with a ratio SO:VCO (5:10) obtained good physical properties, the lowest first-time drop/ shape retention, and a low melting rate compared to the others. The rheological behavior of ice cream is the non-Newtonian fluids with a pseudoplastic behavior. The apparent viscosity decreased with increasing shear rate.

The effect of collisional erosion on the composition of Earth-analog planets in Grand Tack models: Implications for the formation of the Earth

Impact-induced erosion of the Earth’s early crust during accretion of terrestrial bodies can significantly modify the primordial chemical composition of the Bulk Silicate Earth (BSE, that is, the composition of the crust added to the present-day mantle). In particular, it can be particularly efficient in altering the abundances of elements having a strong affinity for silicate melts (i.e. incompatible elements) as the early differentiated crust was preferentially enriched in those. Here, we further develop an erosion model (EROD) to quantify the effects of collisional erosion on the final composition of the BSE. Results are compared to the present-day BSE composition models and constraints on Earth’s accretion processes are provided. The evolution of the BSE chemical composition resulting from crustal stripping is computed for entire accretion histories of about 50 Earth analogs in the context of the Grand Tack model. The chosen chemical elements span a wide range of incompatibility degrees. We find that a maximum loss of 40wt% can be expected for the most incompatible lithophile elements such as Rb, Th or U in the BSE when the crust is formed from low partial melting rates. Accordingly, depending on both the exact nature of the crust-forming processes during accretion and the accretion history itself, Refractory Lithophile Elements (RLE) may not be in chondritic relative proportions in the BSE. In that case, current BSE estimates may need to be corrected as a function of the geochemical incompatibility of these elements. Alternatively, if RLE are indeed in chondritic relative proportions in the BSE, accretion scenarios that are efficient in affecting the BSE chemical composition should be questioned.

Soybean-Oil-Body-Substituted Low-Fat Ice Cream with Different Homogenization Pressure, Pasteurization Condition, and Process Sequence: Physicochemical Properties, Texture, and Storage Stability.

The purpose of this research was to explore the impacts of different homogenization pressures, pasteurization conditions, and process sequence on the physical and chemical properties of soybean oil body (SOB)-substituted low-fat ice cream as well as the storage stability of SOB-substituted ice cream under these process parameters. With the increase of homogenization pressure (10–30 MPa), the increase of pasteurization temperature (65 °C for 30 min–85 °C for 15 min), and the addition of SOB before homogenization, the overrun and apparent viscosity of ice cream increased significantly, and the particle size, hardness, and melting rate decreased significantly. Thus, frozen dairy products of desired quality and condition could be obtained by optimizing process parameters. In addition, the SOB ice cream showed better storage stability, which was reflected in lower melting rate and hardness and more stable microstructure compared with the full-milk-fat ice cream. This study opened up new ideas for the application of SOB and the development of nutritious and healthy ice cream. Meanwhile, this research supplied a conceptual basis for the processing and quality optimization of SOB ice cream.

Investigation on the regulation mechanism of Fe2O3 / SiO2 on ash melting and flow behavior under gasification conditions

ABSTRACT Stable flow and discharge of the slag in an entrained flow gasifier are the key factors to ensure the long-term stable operation of gasifier. In this work, the melting and flow behavior of coal ash with different Fe2O3/SiO2 ratios was studied in a reduced atmosphere. The results show that the viscosity of slag decreases significantly with the increase of Fe2O3/SiO2. And the critical viscosity-temperature (TCV) decreases from 1309°C to 1226°C. It is found that more than 90% of iron ions exist in the form of Fe2+ in liquid slag by chemical titration. There are more simple ion clusters with low bridge oxygen number (BO) with the increase of Fe2+ and lead to depolymerization of slag. Furthermore, the ash with high SiO2 content can be transformed into slag with high viscosity at a low melting rate by the analysis of the slag area curve and X-ray diffraction pattern, which is considered to be controlled by the “softening-melting” mechanism. The ash with high Fe2O3/SiO2 can be transformed rapidly into a low viscosity liquid at a short melting interval, which follows the “melting-dissolution” mechanism. And it is helpful to promote the formation of low-temperature eutectics with the increase in Fe2O3/SiO2 by thermodynamic calculation. Research on the melting mechanism of slag will provide theoretical support for the regulation of slag flow characteristics.

Cambrian rift magmatism recorded in subvolcanic sills of the Ediacaran-Cambrian La Ciénega Formation, NW Mexico

Mafic-ultramafic subvolcanic metabasalt sills intrude Ediacaran and Cambrian strata of the La Ciénega Formation of Sonora, Mexico. Sills are typically 1–7.5 m thick, with minor associated thin (∼10 cm thick) intrusions. Sills are typically bed parallel with upper and/or lower tempered (quenched) borders and porphyritic textures characterized by abundant olivine and pyroxene pseudomorphs that have been transformed to clay and carbonate minerals. Metamorphic halos in adjacent dolostones and quartzites occur at the bottom and top contacts, and metabasalt sills contain carbonate veins typical of hydrothermal alteration and mobilization. Unlike surface flows of the overlying Cerro Rajón Formation, all sills in the La Ciénega Formation lack evidence of crystal settling, yet evidence for assimilation of country rocks is present. Assimilation is more typical of sills rather than flows and is diagnostic of sills in the El Arpa Formation, a stratigraphically lower unit in the succession. Actinolite-chlorite-albite metamorphic mineral paragenesis suggests low-grade greenschist facies metamorphism for these metabasaltic rocks. Although their primary mineralogy is obscured due to alteration, olivine and clinopyroxene pseudomorphs are present and their major and trace element geochemistry suggest they were derived from alkaline basaltic magmas with low (normalized) SiO2N (22.7–43.1 wt%), high MgON (7.25–16.6 wt%), and high TiO2N (4.04–6.27 wt%). Immobile trace elements suggest these sills were originally alkaline rift-related basalts with OIB-type signatures. Tectonic discrimination diagrams suggest continental rift magmatism with low geochemical evolution ratios and relatively low mantle melting rates when compared to contemporaneous rift related magmatism. Sr-Hf-Nd-Pb isotopes suggest the metabasalts originated from an Enriched Mantle I (EMI) reservoir and melting occurred during adiabatic decompression. These geochemical characteristics are remarkably similar to volcanic rocks of the Cerro Rajón Formation. The inferred magmatic composition, mantle melting rates, petrography and field relations of the La Ciénega Formation metabasalt are consistent with a low viscosity feeder system like that envisaged to have sourced volcanic rocks of the overlying Cambrian (Terreneuvian) Cerro Rajón Formation. Together, evidence from these two volcanic units is consistent with a Cambrian continental rift event close to the onset of the Sauk transgression.

Sensitivity analysis of design parameters for melting process of lauric acid in the vertically and horizontally oriented rectangular thermal storage units

Widespread commercialization of PCM-based latent heat storage systems is limited by the low melting and solidification rates during the phase transition process. In this study, fins are used to enhance the phase change process. A parametric study is conducted to understand the effect of fins on the thermal performance of vertically- and horizontally-oriented rectangular storage tanks. Throughout simulations, the fin volume, and thereby the mass of PCM in the tank, were kept constant. It was observed that the horizontal enclosures can take advantage of the development of strong natural convection flow until near the end of the melting process, whereas with vertical counterparts the strength of the convection currents was diminished during the shrinkage stage. The results suggest that longer and thinner fins are more beneficial for enhancing the melting rate than shorter and thicker fins. It was concluded that for horizontal enclosures with fin lengths of 25 and 35 mm, increasing the number of fins does not necessarily shorten the melting time. The maximum melting time reduction compared to the 3-fin vertical enclosure with a fin length of 25 mm (chosen as our benchmark case) was 75.1% when nine 45-mm-long fins are used in a horizontal enclosure.

Construction of egg white protein particle and rhamnolipid based emulsion gels with β-sitosterol as gelation factor: The application in cookie

This study explored the construction of egg white protein particles (EWPP) and/or rhamnolipid (Rha) based emulsion gels with β-sitosterol (Sit) as gelation factor. The properties of the emulsion gels and the application in cookies were investigated to further reveal the functional mechanism of each component. The rheological and microstructure results of the emulsions showed that emulsion gels had suitable plastic texture with lower melting rate and faster cooling rate compared with butter. EWPP stabilized the droplet while Rha reduced the droplet size and enhanced the fluidity of the emulsion gels. In cookie system, Sit in the emulsion gels provided the appropriate hardness and uniform matrix with emulsifiers. EWPP and Rha effectively improved the appearance, texture and mouthfeel of cookies and extended cookies’ frangibility during storage. The constructed composite emulsion gels showed promising potential as plastic fat substitutes, to be used in healthy bakery systems to decrease saturated fatty acids.

An experimental and numerical study on phase change material melting rate enhancement for a horizontal semi-circular shell and tube thermal energy storage system

In the present study, the melting characteristics of a lauric acid in a semi-circular and circular latent heat thermal energy storage unit have been studied. The low melting rate of phase change materials in the lower half of a circular heat storage unit can be enhanced by confining the phase change material in the upper region by configuring the outer shell of a conventional circular latent heat thermal energy storage unit into a semi-circular shape. The recent literature shows that no work has been carried out on the effect of the melting performance of phase change material in a semi-circular latent heat thermal energy storage unit hence an effort has been made to investigate the melting performance of phase change material experimentally and numerically for semi-circular latent heat thermal energy storage unit. The enhancement in the melting rate at three different inner tube position values from the bottom surface of outer semi-circular shell has been investigated and it is found that the enhancement is more when the inner tube is nearest to the bottom surface of the outer shell.The semi-circular heat storage unit is also compared with circular heat storage unit by considering the equal volume of phase change material in both the cases. The semi-circular latent heat thermal energy storage system shows enhancement in melting performance of phase change material as compared to circular latent heat thermal energy storage system. The semi-circular latent heat thermal energy storage system melts the phase change material completely in almost half time as compared to circular latent heat thermal energy storage system. It is found that the thermal energy stored in phase change material for semi-circular latent heat thermal energy storage system is 416.4 kJ which is 12.04 % more as compared to thermal energy stored of phase change material for circular latent heat thermal energy storage for the same time duration of 4800 sec. It is also found that the maximum thermal energy storage rate attained in semi-circular latent heat thermal energy storage system is 0.15 kW whereas in circular latent heat thermal energy storage system it is 0.13 kW which is 25 % higher as compared to that of circular latent heat thermal energy storage system.

Influence of coconut residue dietary fiber on physicochemical, probiotic (Lactobacillus plantarum ATCC 8014) survivability and sensory attributes of probiotic ice cream

Probiotic ice cream serves as a functional food, but potential loss of probiotic viability occurs during product formulation, processing, and storage. Hence, this study aims (1) to formulate a probiotic (Lactobacillus plantarum ATCC 8014) ice cream added with coconut residue, (2) to determine the impact of the coconut residue on probiotic ice cream characteristics during 60 days of storage, and (3) to assess the acceptance of the ice cream enriched with probiotics and coconut residue. The ice cream was produced by using non-fat milk powder, milk fat, heavy cream, sugar, egg yolk, stabilizer, and maltodextrin, added with 1% of L. plantarum and different concentrations of coconut residue fiber (0.01–0.03 g/mL). The results revealed that ice cream incorporated with 0.02 g/mL of coconut residue was the best formulation for probiotic ice cream production. Throughout the storage period, it possessed stable probiotic viability, soft texture, low melting rate, high protein, low-fat, appropriate pH for probiotics, and acceptable sensory ratings for overall consumer acceptance. The synergistic combination of coconut residue and probiotics in ice cream is a potentially novel strategy for producing a nutritious dessert item beneficial to human health as well as reducing potential pollution by the agricultural industry.