Melting Texture Research Articles

From fat crystals to creamy texture: Unraveling the role of fatty acid composition in ice cream stability and quality

To fundamentally elucidate the impact of fat composition on ice cream properties, this study employed controlled variable methods, utilizing anhydrous milk fat (AMF), palm oil (PO), and coconut oil (CO) as fat sources. Thermodynamic analysis showed that increasing saturated and long-chain fatty acids doubles the crystallization rate (Kz), significantly enhancing crystalline solid fat content (CSFC) at −5 °C. This improvement increases the ice cream's resistance to melting and structural collapse. XRD and PLM analyses revealed that higher levels of these fatty acids promote the β’ crystal formation and elongated, one-dimensional crystals, accelerating partial coalescence by 10–40 %. This results in a denser, more stable fat network, reducing melting rates by 20–40 % and improving freeze-thaw stability by 2–5 times. These findings offer practical guidance for improving ice cream formulations to enhance melting resistance and texture stability, particularly in commercial frozen dessert production.

Using harvest maturity and accumulated cold units predicts postharvest chilling requirement for ripening capacity and buttery-juicy melting texture duration in European pears

Using harvest maturity and accumulated cold units predicts postharvest chilling requirement for ripening capacity and buttery-juicy melting texture duration in European pears

Applications of 1-methylcyclopropene concentrations and timing in relation to sunlight-related core browning in ‘Bartlett’ pears after extending regular-air storage

Core browning (CB) is a crucial physiological disorder that occurs in ‘Bartlett’ pears after excessive storage. Furthermore, environmental factors such as sunlight exposure cause serious related disorders during storage. 1-methylcyclopropene (1-MCP) positively delays the development of disorders, but results in poor eating quality at retail. Therefore, the primary purpose of this study was to evaluate whether sunlight exposure impacts the development of CB in ‘Bartlett’ pears and to develop optimal postharvest 1-MCP strategies for the pear industry to extend the fruit’s lifespan and deliver desirable eating quality to consumers that prefer melting texture. Over the course of a three-year evaluation, sunlight-exposed (SE) pears consistently displayed a higher CB index than the control and non-exposed (NE) pears after 150 d of regular-air (RA) storage at − 1.1 ± 0.5 °C plus 5 d at 20 ± 0.5 °C. The rapid development of CB was facilitated by decreases in ethylene production rate (EPR), peel chlorophyll content (PCC), and titratable acidity associated with increases in malondialdehyde and soluble o-quinones. Applying 0.15 and 0.3 μL L−1 1-MCP after 15 d of harvest completely protected the fruit from CB for up to 150 d of RA storage. However, these treated pears did not ripen. Lowering the 1-MCP concentration to 0.075 μL L−1 and postponing treatment to 60 d after harvest could control the CB index in the 1.53–2.33 range with a normal ripening process. For SE pears, the use of 0.15 μL L−1 1-MCP applied after 60 d of harvest reduced the CB index to 1.63 without impairing ripening capacity. It was difficult for the pear industry to monitor the EPR of 1-MCP-treated pears over the entire storage period. However, when the PCC of the treated pears fell to 0.4–0.5 IAD after 5 d of ripening, these pears could recover their ethylene generation capacity and softening behavior. Overall, the 0.15–0.075 μL L−1 1-MCP applied after 60 d of harvest provided great benefits in delaying CB development, improving storability, and retaining ripening capacity in SE ‘Bartlett’ pears following the prolonged RA storage.

CHEESE WITH REDUCED SALT CONTENT

Nowadays, there is growing awareness about reduced fat food as well as free fat products. Low fat milk products, particularly low and salt cheese represent a good choice for the development of new products with functional properties. Consumers are always looking forward to desirable and healthy products. Therefore, consumer's demand for low-fat/calorie products has significantly raised in an attempt to limit health problems, to lose or stabilize their weight and to work within the frame of a healthier diet. Removing all or only part of the fat and salt from cheese can negatively affect its taste, texture, and functionality. Many of the low-fat and salt cheeses have an uncharacteristic taste, greater transparency, less melting, rubbery and resinous texture. To overcome these shortcomings, during the production of low-fat and salt cheese, safe and convenient ingredients have been introduced in the dairy industry that improve its texture and taste, increase its shelf life, improve its appearance, while the product is not inferior to the characteristics of the standard type of cheese. However, despite the efforts made to improve the sensory and functional properties of low-fat and salt cheese, it is ageneral finding that users are still skeptical about its selection and consumption. To that purpose, reducing fat and sodium in cheese and maintaining its safety and quality continues to be a challenge for the dairy industry in highly developed countries.

Physiological disorders, textural property, and cell wall metabolism of ‘Gem’ pears (Pyrus communis L.) affected by oxygen regimes and harvest maturity under controlled atmosphere storage

The primary purpose of this study was to develop optimal controlled atmosphere (CA) strategies for the pear industry to utilize ‘Gem’ pears. The influences of two O2 regimes (1.0% O2 and 2.2% O2 [commercial practice concentration] with ∼0.05% CO2) on decay, physiological disorders (i.e. internal breakdown, superficial scald, and black speck), storage and eating quality attributes, cell wall components, and cell wall-modifying enzymes were evaluated at two harvest maturities (H1; 48.01 N; H2; 42.19 N) of ‘Gem’ pears. Earlier harvested pears (H1) stored under regular-air (RA) conditions had lower rates of superficial scald and internal breakdown relative to later harvested pears (H2), especially in extended storage (8–10 months). However, storage and eating quality for air-stored H1 and H2 fruit deteriorated after 6 months. CA regimes extended ‘Gem’ storage longevity from 8 to 10 months, with 1.0% O2 resulting in lower incidences of superficial scald and internal breakdown disorders and higher peel chlorophyll content and titratable acidity by delaying the peak of ethylene production rate (EPR) compared to 2.2% O2. Notably, the rates of black speck in H1 and H2 fruit were controlled at below 5% in both O2 regimes. Furthermore, 1.0 and 2.2% O2 stored H1 and H2 pears ripened and developed a melting texture with full flavor and juiciness during 6–8 months of storage. Additionally, the water-soluble (WSP), cyclohexanetrans-1,2-diaminetetra-soluble (CSP), and Na2CO3-soluble polyuronides (SSP) combined with pectin methylesterase (PME), α-arabinofuranosidase (α-ARF), and β-galactosidase (β-GAL) contributed to fruit softening and desirable eating quality in ‘Gem’ pears. In conclusion, 2.2% O2 with ∼0.05% CO2 improved the fruit quality of ‘Gem’ pears harvested at 48.01 N, while the quality of fruit harvested at 42.19 N or below could be improved by the application of 1.0% O2.

THE EFFECT OF RED BEAN ADDITION ON THE MELTING POWER AND ACCEPTABILITY OF ICE CREAM

Utilization of red beans to be used as food ingredients is not maximized. Ice cream at room temperature melts easily and has a less soft texture, this is due to several factors, one of which is the emulsifier. To improve the quality of ice cream, researchers use natural emulsifiers in the form of red beans. The aim of this study was to determine the effect of the addition of red beans on the melting power of ice cream and organoleptic properties (color, aroma, taste and texture) of ice cream. The research design was a Completely Randomized Design (CRD) with 5 different treatments of adding red beans to ice cream, namely 0%, 30%, 50%, 70% and 100% with data analysis using the SPSS One way-ANOVA test for normal data, Kruskall-Wallis test for abnormal data, as well as Duncan's advanced test. The results showed that the addition of red beans had a significant effect on melting power (0.00<0.05), color (0.00<0.05), and texture (0.00<0.05). The addition of red beans had no significant effect on aroma (0.41>0.05) and taste (0.011>0.05).

Evaluation of the effect of partial hydrolysis ethyl cellulose on physicochemical properties of soybean oil oleogel

SummaryThe effects of the solvent composition of ethanol and acetic acid (50/50 and 70/30 v/v), time (30 and 60 min) and temperature (65 and 95°C) of hydrolysis were conducted on the structural and physicochemical properties of ethyl cellulose (EC). Differential scanning calorimetry (DSC) and capillary viscometer results revealed that EC hydrolysis significantly decreased glass transition temperature (Tg) and intrinsic viscosity. FTIR spectra of hydrolysed EC (H‐EC) revealed a breakdown of many glycosidic bonds. The oleogels were prepared by H‐EC at the concentration of 6 wt%. Results showed that hydrolysis conditions significantly affected oleogel formation and strength. An optimal oleogel structure was achieved with H‐EC at 65°C, 50/50 solvent ratio (H‐EC65/50). The rheological analysis of H‐EC65/50 oleogel showed higher strength and a lower melting temperature range than EC oleogel. Microscopic observations confirmed that the H‐EC65/50 forms a new structure with many small cavities, probably the main reason for the firmer gel. The prepared formulation could have potential to prepare reduced fat formulations with the suitable melting point and texture.

Effects of Soybean Oil Body as a Milk Fat Substitute on Ice Cream: Physicochemical, Sensory and Digestive Properties.

Soybean oil body (SOB) has potential as a milk fat substitute due to its ideal emulsification, stability and potential biological activity. In this study, SOB was used as a milk fat substitute to prepare ice cream, expecting to reduce the content of saturated fatty acid and improve the quality defects of ice cream products caused by the poor stability of milk fat at low temperatures. This study investigated the effect of SOB as a milk fat substitute (the substitution amount was 10–50%) on ice cream through apparent viscosity, particle size, overrun, melting, texture, sensory and digestive properties. The results show SOB substitution for milk fat significantly increased the apparent viscosity and droplet uniformity and decreased the particle size of the ice cream mixes, indicating that there were lots of intermolecular interactions to improve ice cream stability. In addition, ice cream with 30% to 50% SOB substitution had better melting properties and texture characteristics. The ice cream with 40% SOB substitution had the highest overall acceptability. Furthermore, SOB substitution for milk fat increased unsaturated fatty acid content in ice cream and fatty acid release during digestion, which had potential health benefits for consumers. Therefore, SOB as a milk fat substitute may be an effective way to improve the nutritional value and quality characteristics of dairy products.

Valorization of Vitellaria paradoxa butter in cosmetics and agrifood in Africa

Forest species are very abundant in African ecosystems and contribute to the economy of households, through their use in cosmetics, pharmaceuticals and agri-food. Among these species, Vitellaria paradoxa (sapotaceae) is a tree that can reach about fifteen meters, which grows exclusively in wooded savannas in Africa. Its area of ​​distribution is Senegal, Mali, Burkina Faso, Guinea Bissau, Guinea, Sierra Leone, Côte d'Ivoire, Ghana, Togo, Benin, Nigeria, Cameroon, Chad and Ethiopia. The purpose of this study was to highlight the forms of valuation of shea butter in the food industry and in cosmetics. To do this, we carried out a literature review. The results revealed that shea butter is a fat extracted from the kernels of the shea fruit. It is obtained by shelling, drying and crushing the nuts. Crushed seeds and then mixed with water. Once immersed in water, the impurities will come out naturally from the butter and thus settle in the bottom of the container. Then, the butter that has remained on the surface is collected, and kneaded, to be cooked for a long time at a very low temperature. The water evaporates, leaving only room for the oil, which will be manually filtered through muslin and then conditioned. Once at room temperature, the butter (melted into oil) regains its solid and melting texture. This butter, for its properties, is on considerable importance in food industry and cosmetics. Thus, shea butter is used in cooking (edible oils), in pastry products, confectionery and in chocolate industry as a substitute for cocoa butter. In cosmetics, it is best known for its moisturizing and softening properties of the skin. It is also used as an excipient in cosmetic formulations such as ointments, shampoos, toilet soaps and in creams.

The downregulation of PpPG21 and PpPG22 influences peach fruit texture and softening.

The downregulation of PpPG21 and PpPG22 expression in melting-flesh peach delays fruit softening and hinders texture changes by influencing pectin solubilization and depolymerization. The polygalacturonase (PG)-catalyzed solubilization and depolymerization of pectin plays a central role in the softening and texture formation processes in peach fruit. In this study, the expression characteristics of 15 PpPG members in peach fruits belonging to the melting flesh (MF) and non-melting flesh (NMF) types were analyzed, and virus-induced gene silencing (VIGS) technology was used to identify the roles of PpPG21 (ppa006839m) and PpPG22 (ppa006857m) in peach fruit softening and texture changes. In both MF and NMF peaches, the expression of PpPG1, 10, 12, 23, and 25 was upregulated, whereas that of PpPG14, 24, 35, 38, and 39 was relatively stable or downregulated during shelf life. PpPG1 was highly expressed in NMF fruit, whereas PpPG21 and 22 were highly expressed in MF peaches. Suppressing the expression of PpPG21 and 22 by VIGS in MF peaches significantly reduced PG enzyme activity, maintained the firmness of the fruit during the late shelf life stage, and suppressed the occurrence of the "melting" stage compared with the control fruits. Moreover, the downregulation of PpPG21 and 22 expression also reduced the water-soluble pectin (WSP) content, increased the contents of ionic-soluble pectin (ISP) and covalent-soluble pectin (CSP) and affected the expression levels of ethylene synthesis- and pectin depolymerization-related genes in the late shelf life stage. These results indicate that PpPG21 and 22 play a major role in the development of the melting texture trait of peaches by depolymerizing cell wall pectin. Our results provide direct evidence showing that PG regulates peach fruit softening and texture changes.

Imitation cheese – New insights to relations between microstructure and functionality

The objective of this study was to gain knowledge about the impact of a shift from a protein dominated to a starch dominated continous phase. Furthermore, to determine differences in fat emulsification on the macroscopic behavior of imitation cheese when casein is replaced by chemically modified starch. A novel confocal laser scanning microscopy approach was applied to study the impact of imitation cheese microstructure on melting properties and texture. Using a combination of the dyes FITC, Fast Green, and Nile Blue showed great potential for visualizing structures of complex foods containing both starch, protein, and fat. The macrostructural properties were assessed by textural analysis and rheological temperature sweep and the Schreiber melt test. The hardness and rigidness of imitation cheeses increased with increasing starch concentration. The largest area increase after melting was observed for the imitation cheese with the largest fat droplets. Larger fat droplets indicated reduced fat emulsification. An emulsifying starch decreased the fat droplet size and enabled production of imitation cheese with total casein substitution. This research provides valuable information about the predictors for imitation cheese functionality. The study showed that the melting properties of imitation cheese could be correlated to microstructural stability by determining the fat emulsification.

The influence of pre- and postharvest 1-MCP application and oxygen regimes on textural properties, cell wall metabolism, and physiological disorders of late-harvest ‘Bartlett’ pears

Late-harvest (LH) pears are prone to postharvest disorders and eating-quality deterioration in storage and retailing. The purpose of this work was to evaluate the effects of pre- and post-harvest 1-methylcyclopropene (1-MCP, Harvista (H) and SmartFresh (SF)) on LH ‘Bartlett’ pears under the various O2 regimes. Spraying 320 μL L−1 H delayed fruit maturation and suppressed ethylene production rate (EPR) when pears were harvested at 70.51 N (LH, whereas commercial harvest (CH) at 75.04 N). However, the H-treated LH fruit had 100 % decay after 5 months of regular-air (RA) storage. The 0.15 μL L−1 SF and SF + 160 μL L−1 H extended melting texture life of LH fruit to 5 months with high levels of water-soluble polyuronides (WSP) and CDTA-soluble polyuronides (CSP) and activities of pectin methylesterase (PME), pectate lyase (PL), and α-arabinofuranosidase (α-ARF). Raising H application concentration from 160 to 320 μL L−1 in H + SF treatments resulted in blockage of ripening capacity. Decreasing O2 concentration from 2 to 1 % did not impact LH pears’ ripening, but effectively curtailed the development of melting texture in H-treated LH fruit by suppressing EPR, degradation of pectin polyuronides, and activities of PL and β-galactosidase (β-GAL). Furthermore, applying SF in H-treated LH pears stored in 1 or 2 % O2 resulted in the loss of ripening capacity. Results indicated that 160 μL L−1 H + SF and H at 160−320 μL L−1 extended the melting period and controlled physiological disorders in LH ‘Bartlett’ pears for 5 and 7 months of storage in RA and 2 % O2, respectively.

Modification of pork‐skin jelly by enzymatic cross‐linking: melting resistance and quality improvement

SummaryImprovements of melting resistance and quality by modification of pork‐skin jelly through enzymatic cross‐linking were studied, and the mechanism of quality improvement was discussed in this work. Gel strength, springiness and chewiness of modified gel increased significantly (P < 0.05). Transglutaminase (TGase) also improved the viscoelasticity, stability and melting resistance of gel system, as proved by rheological analysis. Sensory evaluation showed that increase in texture need to be moderate and the utilisation of 0.6% TGase was the most appropriate for pork‐skin jelly. Significant effects of TGase on inducing protein cross‐link and aggregation were confirmed by determining rheology during enzyme treatment and cross‐linking extent of pork‐skin soup. Correlation analysis showed TGase could improve melting temperature and texture by facilitating cross‐linking. Covalent interaction based on ε‐(γ‐glutamyl)‐lysine induced by TGase could play the main role in these improvements. This study suggested that TGase could be applied to design gelatin‐based food for tailored quality properties through enzymatic cross‐linking.

Improving storability, physiological disorders, and antioxidant properties of ‘Bartlett’ and ‘d’Anjou’ pears (Pyrus communisL.) by pre‐harvest 1‐methylcyclopropene spraying

SummaryEthylene continues to be a major factor influencing quality of European pears during storage. Although research has been done on the effect of pre‐harvest 1‐methylcyclopropene (1‐MCP) on physiological characteristics in pears, a full understanding of cultivar response and antioxidant metabolism remains elusive. Spraying 1‐MCP on ‘Bartlett’ and ‘d’Anjou’ pears was studied with respect to physiology, storage and eating quality, disorders, and antioxidant properties at two harvest date (H1 and H2) during storage and ripening. Treatment with 1‐MCP extended the harvest window of ‘Bartlett’ and ‘d’Anjou’ pears 3 and 4 days, respectively, without reducing storage or eating quality. Treatment with 1‐MCP reduced ethylene production (EPR) and respiration rates (RR), maintained fruit firmness and green colour during storage and retarded development of desirable melting texture in both cultivars. Additionally, 1‐MCP lowered the incidence of disorders by alleviating membrane lipid peroxidation, retaining high total flavonoids (TF) and antioxidant capacity, and enhancing superoxide dismutase (SOD), catalase (CAT) and ascorbate peroxidase (APX) activity in both cultivars. Overall, pre‐harvest 1‐MCP applications could extend storage time of ‘Bartlett’ and ‘d’Anjou’ pears to 5 and 6 months, respectively, at −1.1 ± 0.5 °C, by reducing ethylene synthesis and enhancing antioxidant metabolism.

Textural property and cell wall metabolism of ‘Golden Bosc’ and ‘d’Anjou’ pears as influenced by oxygen regimes after long-term controlled atmosphere storage

Controlled atmosphere (CA) allows long-term storage of European pears (Pyrus communis L.) without chemical treatment to deliver a natural melting (buttery and juicy) texture for consumers. However, the relationship between textural properties and cell wall metabolism as influenced by O2 regimes has not been comprehensively determined. In this study, ‘Golden Bosc’ and ‘d’Anjou’ pears were stored in 21 (air), 2, 1, or 0.5% O2 with < 0.5% CO2 for up to 8 and 10 months at −1.1 °C plus 7 d of ripening at 20 °C, respectively. Melting texture development in both cultivars showed high correlations with the level of water-soluble polyuronides (WSP) and activity of β-galactosidase (β-GAL). Also, activities of pectin methylesterase (PME) and α-arabinofuranosidase (α-ARF) were associated with softening in ‘Golden Bosc’ pears. Concentrations of CDTA-soluble polyuronides (CSP) and WSP + CSP + sodium carbonate-soluble polyuronides (SSP), as well as ethylene production showed positive correlations to melting texture in ‘d’Anjou’ pears. Reducing O2 concentrations from 21% to 2-–1% and 1–0.5% in ‘Golden Bosc’ and ‘d’Anjou’ pears allowed pears to develop a desirable eating texture during ripening for up to 8 and 10 months, respectively, with a commercially acceptable levels of postharvest disorders. Use of 1–0.5% O2 resulted in a melting texture in ‘Golden Bosc’ pears, but fruit developed more core browning when ripe. These results indicate that O2 regimes regulate textural qualities by influencing WSP level and β-GAL activity.

Linkage and association mapping for the slow softening (SwS) trait in peach (P. persica L. Batsch) fruit

Fruit texture is a crucial quality factor influencing consumer preference and shelf life. Peach (P. persica L. Batsch) is a highly perishable fruit subjected to a rapid softening after harvest. Improvement of peach shelf life is an important breeding objective, stimulating the characterization and exploitation of texture-related traits. Variants of melting (M) texture have captured an increasing interest, following the economic success of “Big Top” nectarine, one of the most cultivated varieties worldwide. “Big Top” fruit maintains a crispy texture for an extended period before the onset of the melting phase, prolonging its shelf life. Genetic determinants regulating this complex trait, defined as slow softening (SwS), are still unknown, mainly because of limitations in phenotyping methods. In this work, a mechanical approach for measuring SwS fruit texture was used to phenotype offspring derived from a cross between “Rebus028” (SwS texture) and “Max10” (M texture). Mechanical parameters were used in linkage mapping, allowing the identification of a major QTL on chromosome 8 (qSwS8.1). The presence of this QTL was validated by a genome-wide association study (GWAS) in a panel of accessions phenotyped for mechanical properties. Less significant signals were also detected by GWAS in other genomic regions, suggesting that additional loci may regulate the SwS trait, possibly depending on the genetic background. The inheritance pattern of the SwS trait and the presence of additional loci are crucial aspects to be addressed in future studies, along with a better characterization of other important textural attributes.

Effects of controlled atmosphere, edible coating, and 1-methylcyclopropene on improving storage quality of ‘Bartlett’ pears after long-term storage

ABSTRACTRecent trends towards greater fresh market use of ‘Bartlett’ pears has increased the need to extend its storage life to prolong the packing and marketing season in the United States Pacific Northwest region. Sixteen and 38%, respectively, of control fruit developed senescence disorders following 5 and 6 months of storage at −1.1°C. Commercial standard controlled atmosphere (CA) conditions (O2 at 1.5 kPa and CO2 < 1 kPa) or edible coating (Semperfresh™, SF) prevent the appearance of senescence disorders for 5 months, but 9% and 16% of fruit, respectively, developed senescence disorders after 6 months. The combination of CA+SF completely inhibited senescence disorders for 6 months. Treatment with CA and SF, alone or in combination, maintained high-storage quality and developed ripening capacity with characteristic melting texture during storage. Senescence disorders were inhibited for 6 months by 0.3 µL l−1 1-methylcyclopropene (1-MCP), alone or combination with CA or CA+SF. In part these pears developed ripening capacity after 6 months of storage. The combination of CA+SF+1-MCP maintained the highest storage quality with dark green colour and hard firmness, which might be associated and proportional with reductions in ethylene synthesis and respiration rate after long-term storage.

Compositional changes in cell wall polyuronides and enzyme activities associated with melting/mealy textural property during ripening following long-term storage of ‘Comice’ and ‘d’Anjou’ pears

Irregular ripening is a major deterrent for the purchase of European pears. Cell wall polyuronides and related- modifying enzymes were investigated in two European winter pears, ‘Comice’ and ‘d’Anjou’, during ripening at 20°C following 5 and 8 months of storage at −1.1°C. Both pear cultivars developed a melting (buttery-juicy) texture and higher water-soluble polyuronides (WSP) in flesh tissue after 5 months, but the pears’ texture quality decreased and a mealy (coarse-dry) texture presented in ‘Comice’ pear after long-term storage. Activities of pectin methylesterase (PME) and α-arabinofuranosidase (α-ARF) in ‘Comice’ pears was positively correlated with texture development, whereas in ‘d’Anjou’ pears polygalacturonase (PG), PME, cellulase (CEL), and β-galactosidase (β-GAL) were more highly correlated with texture. 1-MCP reduced pear ripening by inhibiting ethylene production and the activities of cell wall-modifying enzymes, maintaining higher antioxidants, and alleviating membrane lipid peroxidation. These results indicated melting texture developed in European pears as a result of the synthesis of WSP and increase of PME activity during pear fruit softening.

Influence of a Novel Heat Treatment on Structures and Superconducting Properties of YGdBCO Coated Conductors

Preliminary results for a future superconducting joint between YGdBCO coated conductors (CCs) were reported in this work. A promising heat treatment called as melting diffusion and texture merging to connect CCs was proposed and the influence of different treatment on the texture, the surface morphologies and the superconducting properties of YGdBCO CCs were investigated. The impurity phase such as (YGd)211 and BaCuO generated in partial melting stage can be transformed into textured (YGd)123 via low-temperature recrystallization, which is helpful to form textured interface between two CCs. With a comparison to the partial melting process, the superconducting properties of YGdBCO CCs with recrystallization after partial melting can be recovered in a shorter time of 75 h under flowing O 2 gas. It demonstrates that this heat treatment is prospective to fabricate a superconducting joint for REBCO CCs. This joint work is undergoing in our group.

Effect of solubilised carbon dioxide at low partial pressure on crystallisation behaviour, microstructure and texture of anhydrous milk fat

The crystallisation and melting behaviour, fat polymorphs, microstructure and texture of anhydrous milk fat (AMF) was investigated in the presence of dissolved CO2 (0–2000ppm) under two crystallising conditions (non-isothermal versus isothermal). CO2 was found to induce higher onset crystallisation temperature during cooling from 35 to 5°C at 0.5°Cmin−1. X-ray scattering analysis showed that, in the presence of dissolved CO2, this rapid crystallisation caused the formation of unstable, α polymorph fat crystals. For milk fat crystallised under isothermal condition at 25°C for 48h, dissolved CO2 improved solid fat content, slightly depressed melting temperature and exhibited a sharper melting peak. Microstructure of AMF visualised by Polarised light microscopy of crystallised AMF showed that increasing dissolved CO2 concentration was associated with smaller crystal size and greater crystal number. The bulk properties of the fat appeared to mirror the microstructural differences, in that the texture of CO2-treated AMF was harder under isothermal condition but became softer than untreated AMF under cooling condition. The results of this study are of significance in understanding how CO2 treatment might be used to modulate the crystallisation behaviour of milkfat and thereby the structural development and physical functionality of fat-containing dairy products.