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Recent studies have suggested that in certain environments, tree stems emit methane (CH₄). This study explored the mechanism of CH₄ emission from the stem surfaces of Alnus japonica in a riparian wetland. Stem CH₄ emission rates and sap flux were monitored year-round, and fine-root anatomy was investigated. CH₄ emission rates were estimated using a closed-chamber method. Sap flux was measured using Granier-type thermal dissipation probes. Root anatomy was studied using both optical and cryo-scanning electron microscopy. CH₄ emissions during the leafy season exhibited a diurnally changing component superimposed upon an underlying continuum in which the diurnal variation was in phase with sap flux. We propose a model in which stem CH₄ emission involves at least two processes: a sap flux-dependent component responsible for the diurnal changes, and a sap flux-independent component responsible for the background continuum. The contribution ratios of the two processes are season-dependent. The background continuum possibly resulted from the diffusive transport of gaseous CH₄ from the roots to the upper trunk. Root anatomy analysis indicated that the intercellular space of the cortex and empty xylem cells in fine roots could serve as a passageway for transport of gaseous CH₄., 木の中にガスパイプライン？ --ガス漏れの場所を特定せよ！--. 京都大学プレスリリース. 2022-07-15.

There is limited information available about the physiological content of glyceraldehyde, a precursor of toxic advanced glycation end products. The conventional derivatization method for aldoses using 1-phenyl-3-methyl-5-pyrazolone did not allow reproducible quantification of glyceraldehyde due to the instability of glyceraldehyde compared to other aldoses. We optimized the derivatization condition to achieve high and reproducible recovery of derivatives for liquid chromatography tandem mass spectrometry quantification. Based on the stability of glyceraldehyde during sample preparation and high recovery of spiked standard, the present method provides reproducible quantification of glyceraldehyde in the body. The glyceraldehyde contents in fasting conditions in the rodent liver (mice: 50.0 ± 3.9 nmol/g; rats: 35.5 ± 4.9 nmol/g) were higher than those in plasma (9.4 ± 1.7 and 7.2 ± 1.2 nmol/mL). The liver glyceraldehyde levels significantly increased after food consumption (p < 0.05) but remained constant in the plasma. High fat diet feeding significantly increased plasma glyceraldehyde levels in mice (p < 0.005). In healthy human volunteers, the plasma glyceraldehyde levels remained unchanged after the consumption of steamed rice. In patients with type 2 diabetes, the plasma glyceraldehyde level was positively correlated with the plasma glucose level (r = 0.84; p < 0.0001).

The total number of low‐molecular‐weight compounds in the plant kingdom, most of which are secondary metabolites, is hypothesized to be over one million, although only a limited number of plant compounds have been characterized. Untargeted analysis, especially using mass spectrometry (MS), has been useful for understanding the plant metabolome; however, due to the limited availability of authentic compounds for MS‐based identification, the identities of most of the ion peaks detected by MS remain unknown. Accurate mass values of peaks obtained by high accuracy mass measurement and, if available, MS/MS fragmentation patterns provide abundant annotation for each peak. Here, we carried out an untargeted analysis of compounds in the mature fruit of 25 tomato cultivars using liquid chromatography‐Orbitrap MS for accurate mass measurement, followed by manual curation to construct the metabolome database TOMATOMET (http://metabolites.in/tomato‐fruits/). The database contains 7,118 peaks with accurate mass values, in which 1,577 ion peaks are annotated as members of a chemical group. Remarkably, 71% of the mass values are not found in the accurate masses detected previously in Arabidopsis thaliana, Medicago truncatula or Jatropha curcas, indicating significant chemical diversity among plant species that remains to be solved. Interestingly, substantial chemical diversity exists also among tomato cultivars, indicating that chemical profiling from distinct cultivars contributes towards understanding the metabolome, even in a single organ of a species, and can prioritize some desirable metabolic targets for further applications such as breeding.

Miso, a paste of salted fermented soybean, is a seasoning used extensively in traditional Japanese cuisine. Herein, pyroglutamyl peptides present in miso were identified by a liquid chromatography-tandem mass spectrometry (LC-MS/MS), detecting precursor ions, which generated immonium ion of pyroglutamyl residue. By using this method, 13 pyroglutamyl peptides were identified in four types of miso. Administration of the water extract prepared from 0.6 g soybean miso/kg body weight/day significantly suppressed high fat diet-induced weight gain. A similar effect was exerted by the hydrophobic pyroglutamyl peptide fraction, including pyroglutamyl proline (pEP), pEV, pEI, and pEL. Administration of a mixture of synthetic pEP, pEV, pEI, and pEL in a ratio to that in miso or pEL alone also suppressed the weight gain in a dose dependent manner. These results suggest that the short-chain hydrophobic pyroglutamyl peptides present in miso are effective in suppressing high fat diet-induced obesity.

The role of solid fat content (SFC) within fat particles was examined for its effects on adsorption behaviour at the air–water interface. Three kinds of vegetable oil with different SFC profiles were mixed with a sodium caseinate solution (2% w/w) to prepare the creams, whose fat contents were adjusted in the range of 0–40% w/w. The decrease of interfacial tension at the air–water interface was measured for creams and the sodium caseinate solution, and the ratio of the maximum decrease rate of creams (Δγmax)-to-the sodium caseinate solution (Δγ0max), Δγmax/Δγ0max, was calculated. The interfacial elastic modulus (E′) of creams and sodium caseinate solution was also measured and found to initially increase with time but decreased after the maximum value (E'max). Both Δγmax/Δγ0max and E'max were affected by the temperature, fat content of creams and SFC in fat particles. The largest increase for Δγmax/Δγ0max and E′max was observed when the SFC of creams was between 10 and 50% w/w. The microscopic structures of the air–water interface of creams after whipping were also affected by the SFC, such that fat particles containing 28.4% SFC were found to adsorb and aggregate at the air–water interface layer. These results suggest that the adsorption of fat particles onto the air–water interface and interfacial structure formation by adsorbed fat particles were promoted via partial coalescence.

Some components of bitterness make key flavor contributions to promote the palatability of foods, whereas other components are recognized as aversive signals to avoid consuming harmful substances. These contradictory behaviors suggest that humans tolerate tastes of bitterants based on certain criteria. Here, we investigated human taste tolerance and sensory cues leading to diverse taste tolerance of bitter compounds. Tolerance of eight bitter compounds, which are typically contained in foods, was evaluated by measuring detection and rejection thresholds. The results revealed that the level of tolerance of each compound was variable, and some compounds showed an acceptable concentration regarding the suprathreshold intensity. Tolerance did not depend on the nutritive value or attenuation and accumulation characteristics of bitterness and bitter taste receptors. These results suggest that the criteria controlling tolerance of bitter compounds may be derived from a complex relationship between the taste quality and cognitive process.

Soybeans (Glycine max (L,) Merr,) contain γ-glutamyl peptides and oligosaccharides, and these components play an important role in imparting the “kokumi” taste to foods. To gain insight into the genetic diversities and molecular mechanisms of accumulation of γ-glutamyl peptides and oligosaccharides in soybean, we measured the contents of these components using the Japan and World mini core collections. Similar to other previously reported traits, wide variations were detected among the accessions in the core collections with respect to the content of γ-glutamyl peptides and oligosaccharides. We found a positive relationship between the content of γ-glutamyl tyrosine and γ-glutamyl phenylalanine and between the content of raffinose and stachyose. Furthermore, there were unique accessions that included high levels of γ-glutamyl peptides and oligosaccharides. These accessions may be helpful in understanding the accumulation mechanism of γ-glutamyl peptides and oligosaccharides and to increase the “kokumi” taste components in soybean by performing a genetic analysis.

The whipped cream dispenser is a foaming tool that is an increasingly applied for on-site whipped cream consumption. It creates foams by incorporating nitrous oxide (N2O) or carbon dioxide (CO2) into protein dispersions, while other foaming methods such as agitation and aeration create foam by incorporating air and nitrogen (N2). In this study, a whipped cream dispenser was used to investigate the effects of different gases and proteins on the foaming properties of protein dispersions. Four gases (CO2, N2O, air, N2) and five proteins were used. The results show that a higher foaming capacity was obtained for all the protein dispersions that were prepared with more soluble gases (N2O and CO2). The foam that was prepared with the more soluble N2O was less stable than that prepared with air and N2. Although the impact of proteins on the foam stability was lower than that of gases, the applying different proteins also significantly changed the foam stability.

This work aimed at clarifying the effects of the powder-added phase (water or oil) on the emulsifying properties of avocado powder under various pH (4.0, 5.5, and 7.0) and salt (0 and 1 wt%) conditions. After analyses of colloidal properties of the powder aqueous dispersions, interfacial and emulsifying properties of avocado powder were evaluated in the powder-in-water (p/w) and powder-in-oil (p/o) systems. Under all the aqueous conditions, the avocado surface-active components adsorbed more quickly and densely to the oil-water interface to form more elastic adsorbed layers in the p/o systems than the p/w systems, which could be attributed to the solubilized polar lipids and/or the non-hydrated and non-ionized insoluble particles in the oil phase, resulting in higher accessibility to the interface. Consequently, finer emulsions exhibiting higher stability against flocculation and coalescence were obtained in the p/o systems compared to the p/w systems. Moreover, the p/w emulsions were more sensitive to the environmental changes. These results suggest that the desired emulsifying properties could be achieved by changing the powder-added phase.

The aim of this study was to analyze changes in the surface structure and the inner microstructure of durum wheat pasta during the boiling process. Dried pasta was boiled for 1, 4, 7, or 10 min, and the structure of dried and boiled pasta was observed using polarizing light, laser, and fluorescence microscopy. The degree of gelatinization was measured by polarized light microscopy as well as the β-amylase-pullulanase method. The degree of gelatinization was shown to be larger when evaluated by polarized light microscopy. The surface roughness was evaluated by laser microscopy. The surface roughnesses of dried (non-boiled) pasta and boiled pasta showed different characteristics, and the calculation and analysis of parameters relating to surface roughness indicated that the surface of pasta becomes more uneven as boiling time increases. In principal component analysis of surface roughness, principal components 1 and 2 explained 71.7% of total variance. Principal component 1 mainly reflected the peak frequency and height, and principal component 2 mainly reflected the peak interval. We confirmed by fluorescence microscopy that starch granules began to swell from the outer periphery of the pasta during boiling, and the proportion of gluten network on the outer circumference structure clearly decreased.

The water extract of soybean seeds (Glycine max (L.) Merr.) is nearly tasteless, but “kokumi” taste sensation was confirmed upon addition of a basic umami solution containing glutamic acid, inosine monophosphate, and sodium chloride. To identify the key contributors to the “kokumi” taste sensation in soybean seeds, sensory-guided fractionation, taste sensory analyses, and LC–MS/MS analyses were utilized. γ-glutamyl-tyrosine and γ-glutamyl-phenylalanine were identified as contributors to “kokumi taste”; specifically, these γ-glutamyl peptides imparted the “kokumi” taste sensation at a low taste threshold in a basic umami solution. Raffinose and stachyose, which are sufficiently present in soybean seeds, exhibited a synergistic effect in regard to the enhanced “kokumi” taste sensation of γ-glutamyl peptides. This is the first report that the combined use of γ-glutamyl peptides and oligosaccharides can increase the “kokumi” intensity, which suggests that soybean extracts or soymilk can be used to enhance the “kokumi” taste sensation in food products.

The effects of lavender volatile inhalation on human behaviour and emotions are not reproducible, because several types of lavender essential oils are available in markets. The aim of this study was to determine the key volatile components for the sedative effect of lavender essential oil on human. We tested twenty-seven Lavandula essential oils and analysed their volatile component compositions by means of GC and GC-MS. Volatile component composition of the essential oils was categorized by Principal Components Analysis and seven essential oils were selected for physiological/psychological evaluation. Power spectral analysis on R–R intervals, salivary amylase activity and POMS test showed that some essential oils showed sedative effects on humans. Oils with stimulant effects were also observed. Differences in volatile composition between sedative and stimulant oils suggested that key components of aromachology effects of Lavandula oils were linalyl acetate (sedative effect) and camphor (stimulant...

Mayonnaise-like oil-in-water emulsions with different stabilities—evaluated from the degree of macroscopic defects, e.g., syneresis—were prepared by different formulations and processing conditions (egg yolk weight, homogenizer speed, and vegetable oil temperature). Emulsions prepared with lower egg yolk content were destabilized for shorter periods. The long-term stability of emulsions was weakly related to initial properties, e.g., oil droplet distribution and protein coverage at the interface. Protein aggregation between oil droplets was observed and would be responsible for the instability of emulsions exhibited by the appearance defects. SDS-PAGE results for adsorbed and unadsorbed proteins at the O/W interface suggested that predominant constituents adsorbed onto the interface were egg white proteins as compared with egg yolk components when the amount of added egg yolk was low. In present condition, egg white proteins adsorbed at the O/W interface could be a bridge of neighboring oil droplets thereby causing flocculation in emulsions.

Soybean oil bodies are natural and environment-friendly emulsifying agents from plant resources required as a substitute for emulsifiers such as low-molecular-weight one and animal proteins. The aim of this study was to reveal the interfacial properties and the emulsifying properties of two types of oil bodies extracted from soybean seeds at different pH conditions, that is purified oil bodies (OB) and crude oil bodies (OBC) including storage and other minor proteins. Particle size and zeta-potential measurements and SDS-PAGE revealed that the presence of the involved storage and other minor proteins promoted oil body aggregations and imparted the high zeta-potential to the oil bodies. OB adsorbed onto the oil-water (O/W) interface in closely packed state and formed more elastic adsorbed layer than OBC according to the results from tensiometry. Emulsions stabilized by OB (OB-E) were more stable against oil droplet coalescence than those by OBC (OBC-E) due to the absence of the involved proteins at the emulsion droplet surfaces. Cryo-SEM observation suggests that during emulsification most of the OB and OBC particles adsorbed onto the newly-created O/W interface and then rapidly ruptured.

The stability against solidification during storage and whippability of commercial cream products vary depending on the repetition of heat treatment and homogenization necessary for extended shelf-life. First, the two commercial creams subjected to different times of heat treatment and homogenization were investigated. Among several factors such as the colloidal properties, melting profiles of fat globules and protein content and composition, the amount of proteins present at the fat globule surfaces should play a major role in determining the cream quality probably in relation to the degree of expected partial coalescence of fat globules during transportation and whipping, while the composition of proteins adsorbed to the oil–water interface was not the critical factor affecting the quality of creams. A further step-wise preparation of cream samples in a laboratory scale revealed that the second homogenization significantly reduced the amount of proteins adsorbed to the surface of fat globules. There is a possibility that physical and colloidal macro-ordered properties of whipping creams can be controlled by appropriately managing the homogenization process.

Soy protein isolate (SPI) is a typical commercial product of soybean, widely used as a food ingredient. SPI has long been thought to consist of two major storage proteins, namely, glycinin and β-conglycinin. However, the finding of new protein fractions, lipophilic proteins (LP), which occupy about 30% of SPI, requires us to reconsider the composition and functional properties of SPI. In this review, we consider the origin of LP and its interaction with the two storage proteins referring to recent results on the solubility of LP, glycinin, β-conglycinin, and SPI. The importance of the interaction between LP and the storage proteins is also highlighted by comparing our results with those previously published on the emulsifying properties of LP. The major component of LP is a complex of oleosin-phospholipids, and this complex forms a strong membrane surrounding the oil body in soybean seeds. The possibility of using the oil body as an emulsifying agent is also discussed, and the importance of the interaction between LP and storage proteins is highlighted.

Scope Dietary soy reportedly protects from diabetic nephropathy (DN), but its active components and mechanism of action remain unknown. Methods and results In this study, KKAy mice are fed three types of diet: Dietary soy isoflavones with soy protein (Soy-IP) diet, reduced isoflavones soy protein (RisoP), and oral administration of isoflavones aglycones (IsoAgc). Albuminuria and glycosuria are decreased only in the soy-IP group. The risoP group show reduced expansion of mesangial matrix and renal fibrosis, the IsoAgc group show renal anti-fibrotic and anti-inflammatory effects; however, these renal pathological changes are repressed in the soy-IP group, suggesting the distinct protective roles of soy protein or isoflavones in DN. The isoflavone genistein has a better inhibitory effect on the inflammatory response and cellular interactions in both mouse tubular cells and macrophages when exposed to high glucose and albumin (HGA). Genistein also represses HGA-induced activator protein 1 activation and reactive oxidases stress generation, accompanied by reduced NADPH oxidase (NOX) gene expression. Finally, diabetic mice show a decrease in lipid peroxidation levels in both plasma and urine, along with lower NOXs gene expression. Conclusion The data elucidate the detailed mechanism by which isoflavones inhibit renal inflammation and provide a potential practical adjunct therapy to restrict DN progression.

PyroGlu-Leu is present in certain food protein hydrolysates and traditional Japanese fermented foods. Our previous study demonstrated that the oral administration of pyroGlu-Leu (0.1 mg/kg body weight) attenuates dysbiosis in mice with experimental colitis. The objective of this study was to elucidate why such a low dose of pyroGlu-Leu attenuates dysbiosis in different animal models. High fat diet extensively increased the ratio of Firmicutes/Bacteroidetes in feces of rats compared to control diet. Oral administration of pyroGlu-Leu (1 mg/kg body weight) significantly attenuated high fat diet-induced dysbiosis. By focusing on the production of intestinal antimicrobial peptides, we found that pyroGlu-Leu significantly increased the level of 4962 Da peptides, which identified as the propeptide of rattusin or defensin alpha 9, in ileum. We also observed increased tryptic fragment peptides from rattusin in the lumen. Here, we report that orally administered pyroGlu-Leu attenuates dysbiosis by increasing in the host antimicrobial peptide, rattusin.

We investigated how temperature condition during ultra-high-pressure homogenization (UHPH) affects the colloidal, interfacial, and foaming properties of whey protein isolate (WPI) and micellar casein (MC) using the one of UHPH device, Star Burst (SB). While UHPH treatment generally induces both mechanical force and heating under high operating pressure, we differentiated the effects of “mechanical force (below denaturation point of whey proteins)” and “combination of mechanical force and heating (above denaturation point of whey proteins)” on the proteins by controlling the protein dispersion temperature prior to the SB treatment at 240 MPa. For WPI, the combined use of mechanical force and heating induced the exposure of protein hydrophobic regions leading to a more increase in foaming ability while the sole use of mechanical force caused a more decrease in foam stability due to less adsorption efficiency at the interface. For MC, the sole effect of mechanical force strongly increased foaming ability and foam stability due to the large particle size reduction, rather than the combined use. These results suggested that SB treatment can contribute to expand the possibilities of development of new materials possessing unique physicochemical and functional properties by controlling treatment conditions.

Japanese apricot and avocado powders without chemical modification or complicated processing were firstly applied for stabilizing food emulsions containing soybean oil as a source of clean label ingredients. In this work, Japanese apricot and avocado powders as fiber-rich and lipid-rich emulsifiers, respectively, were studied for evaluating emulsifying properties of the fruit powders. Each powder was dispersed in a water or an oil phase, followed by emulsifying with the other immiscible phase to produce emulsions. A more remarkable effect on emulsifying properties was found when fiber-rich powders were dispersed in a water phase and oil-rich powders were dispersed in an oil phase. In addition, avocado powder-based emulsions showed the high stability against creaming (no phase separation) for at least 24 h stored at 4 °C, and both Japanese apricot and avocado powder-based emulsions presented high stability against coalescence for 14-day storage. The results suggested high possibility that fruit powders can be used as food-grade emulsifiers to stabilize emulsions with high physical stability.

Soy lipophilic protein (LP) is considered to form a major fraction of soy protein isolate, in addition to β-conglycinin (7 S) and glycinin (11 S). LP consists of phospholipid-protein complex and phospholipid-free protein molecules. Surface and foaming properties of LP were compared to those of 7 S and 11 S. These soy protein samples were prepared under mild conditions in order to avoid thermal denaturation, which enabled us to study the effects of heat treatment on surface and foaming properties of the proteins. Without heat treatment, the surface and foaming properties of LP were superior to those of other soy protein fractions, suggesting the phospholipid-protein complex in LP can produce fine bubbles with high drainage stability. Despite low surface and foaming properties of non-heated 7 S and 11 S, heat treatment improved the surface and foaming properties of 7 S and 11 S dramatically, which could be relevant to heat-induced changes in particle size, zeta-potential and surface hydrophobicity of 7 S and 11 S molecules. On the other hand, the foaming ability of LP was declined, but the foam stability was increased to maintain the foam volume up to the final stage of observation, by heating. In the foam stabilized by heated LP, medium sized bubbles as well as fine bubbles were produced. The improved foam stability may be attributed to the combination effect of the delayed drainage from the lamellar phase of fine bubbles and the increased resistance to the bursting of medium sized bubble.

Soybean oil-storing organelles called oil bodies/oleosomes (OBs) are a potential eco-friendly plant-based emulsifier, whereas combinational effects of acid and salt addition on emulsifying properties of OBs were still unclear. This study aimed at investigating colloidal, interfacial, and emulsifying properties of OBs in the presence of acetic acid and NaCl. The purified OBs isolated from soybean seeds were dispersed into 10 mM acetate or phosphate buffer solutions at pH 4.0–7.0 with different NaCl concentrations between 0 and 100 mM. Without added NaCl, the purified OBs were finely dispersed at pH 4.0 and 4.5 by electrostatic repulsion, whereas they aggregated at pH 5.0 and 5.5 probably due to small net charge. The NaCl addition caused screening of the electrostatic interaction between OBs and induced salting-in of OBs. Interfacial tension and interfacial viscoelasticity analyses showed that strongly-charged OBs tended to more slowly sparsely adsorb onto oil-water interface to form less elastic adsorbed layer; this tendency might result from electrostatic adsorption energy barrier between the adsorbed- and non-adsorbed OBs. The OB-stabilized emulsions slightly coalesced under at pH 4.0 and 4.5 without added NaCl probably due to a relatively small amount of the surface protein load. Under all the other tested pH (4.0–7.0) and NaCl (0–100 mM) conditions, the OB-stabilized emulsions were stable against coalescence because of the improved surface load. These results suggest that OBs can be widely applicable for various food emulsions as a potential eco-friendly emulsifier with the appropriate formulation of acid and salt.

This study was aimed at characterizing the physicochemical properties of whey protein isolate (WPI)-xanthan gum (XG) complexes and the oil-in-water (O/W) type emulsions stabilized with the complexes. The WPI-XG complexes were fabricated under acidic conditions (pH 4.0) by changing the XG content (0.05–0.2%) of the complexes, and the O/W emulsions were prepared at 20% oil content at pH 4.0. In addition to the physicochemical properties, the assembly of the complexes and the interfacial microstructures of the emulsions were also explored by cryo-SEM to determine the stabilization mechanism of the emulsions. The results revealed that the WPI-XG complexes were around 100 nm in diameter and had a lower isoelectric point (≈pH 2.0) compared to un-complexed WPI (≈pH 4.5). The droplet size of the emulsions did not change during storage at 25 °C for 28 days when the XG content was over 0.12%. Cryo-SEM showed that the WPI-XG complexes (or WPI globules) adsorbed onto the surface of oil droplets with XG fibrils extending from WPI, contributing to the emulsion stability. It was suggested that these structural features of the complexes contributed to enhancing the emulsion stability. The findings of this study will be useful for the development of emulsified foods with novel functionality, by using natural ingredients.

The alkaline extract of Enoki mushroom (Flammulina velutipes) has been shown to have ice crystal growth inhibiting activity, and its beneficial effect on the quality preservation of frozen foods is highly expected. The purpose of this study was to investigate the effect of Enoki mushroom extract which has an ice recrystallization inhibiting activity on the quality of frozen whipped creams. Whipping creams with different milk/vegetable fat compositions were prepared. The proportion of % milk fat and % vegetable fat was given as follows; 0:37, 10:28, 20:20 and 40:0, respectively. Whipped foam samples were frozen and stored at −20 °C, then the effect of adding 0.1% Enoki mushroom extract was tested. Fresh dairy flavor and smooth melt in mouth texture was deteriorated during the course of frozen storage for 37 days, and the frequency is higher in whipped creams with high milk fat content. Addition of 0.1% Enoki mushroom extract ameliorated these quality changes and significantly retained moisture content. Microscopic observation of the internal structure of frozen foam samples by cryo-SEM revealed that the ice crystal aggregates grown in the emulsified solid phase were reduced by adding Enoki mushroom extract. GC/MS analysis of the flavor components revealed that the content of furan compounds (furfural and 2-furanmethanol) was increased by 1.7 times in control foam samples during frozen storage, whereas the furan compounds in whipped foam sample containing Enoki mushroom extract did not increase after frozen storage. Based on these findings, it is proposed that ice crystal growth at the emulsified solid phase causes the sublimation of water on the surface of frozen whipped cream and destruction of the network structure of fat globules results in the quality changes after thawing. Enoki mushroom extract was found to retard ice crystal growth in whipped cream, thus supposed to reduce the quality changes during frozen storage.

Pancakes served as a dessert with creams and fruits toppings nowadays stored under refrigerated conditions are often subjected to significant changes in physical properties recognized as quality deterioration, which is efficiently prevented by including small molecule emulsifiers into commercial pancakes formulations. In order to reveal these molecular prevention mechanisms in the real multicomponent wheat-based products, small molecule emulsifiers with various HLB values and head group size were formulated into pancake samples and their physical properties evaluated. Starch retrogradation, emulsifier-starch inclusion complex formation and gelatinization behaviors were followed by the texture profile analysis, differential scanning calorimetry, iodine colorimetry and confocal laser scanning microscopy. Hardening of the pancake samples varied with the type of emulsifiers, which in general reduced the retrogradation of starch. This reduction was dominantly attributed to the emulsifier-starch complex formation, particularly with amylose molecules, probably leading to less leaching of the starch molecules from the starch granules. These findings are of practical use in selecting effective emulsifiers that prevent hardening of pancakes. The degree of complexation was partially explained by the HLB and head group size of the emulsifiers, while it can be also significantly affected by interactions between the emulsifier and other components in the pancake mixture, like milk and eggs.

The effects of autoclave and microwave heating on the protein and oil in soybean seeds were investigated under low moisture conditions. The nitrogen solubility index (NSI) decreased on heating. The reduction in the NSI was accompanied by an increase in the size and deformation of the oil bodies in the cellular tissue of soybean seeds. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis revealed that lipoxygenase was susceptible to heat denaturation, but 7S and 11S globulins were only partially denatured. The partial denaturation of the proteins was confirmed by Fourier transform infrared spectroscopy measurements. The ratio of oil to protein peaks increased with increasing heating, suggesting the exudation of oil to the surface or outside of oil bodies. Microwave heating is more efficient in changing the oil distribution in soybean seeds than autoclave heating. On the other hand, the degree of protein denaturation is lower after microwave heating.

This paper reports the effects of adding talc particles on the physical properties of palm oil (PO)-based shortening formed by working refined PO (RPO) after rapid cooling. We examined the thermal and viscoelastic behavior of RPO in bulk fat systems, and the polymorphism and hardness of the shortening in the presence and absence of talc particles. In addition, the microstructure of fat crystals formed was observed. The effects of talc addition are summarized as follows: (i) When RPO was cooled at a rate of 5°C/min, crystallization of the high-melting fraction, including tripalmitoylglycerol (PPP) and 1,3-dipalmitoyl-2-oleoyl glycerol (POP), was preferentially promoted to form small-sized microcrystals. During cooling, the increase in the viscoelasticity of RPO was suppressed at low temperatures. (ii) When the shortening was stored at 5°C, β′-crystallization of 1-palmitoyl-2,3-dioleoyl glycerol (POO) and β-crystallization, probably of a molecular compound (MC) of POP and 1,2-dipalmitoyl-3-oleoyl glycerol (PPO), were delayed compared to β′-crystallization of PPP and POP. During storage, the homogeneity of the fat crystal dispersion improved and the hardness of the shortening decreased. These results indicate that talc improved the physical properties of the PO-based shortening by changing the crystallization kinetics and the networking processes of the fat crystals. Practical applications: The present study showed that adding talc particles effectively improved the physical properties of palm oil (PO)-based shortening during storage. This is considered beneficial for resolving problems in the quality control of PO-based products, such as post-hardening and the formation of granular crystals due to low rates of crystallization. Storage modulus (G′) of refined palm oil (RPO) with and without talc particles in bulk fat systems, obtained from dynamic viscoelasticity measurements during cooling at a rate of 5°C/min. Adding talc particles drastically changed the three-stage increases in G′ of pure RPO, promoting the first-stage increase but suppressing subsequent increases at low temperatures.

Effects of oil droplet coalescence on the release of fruity aroma compounds from milk proteins or a modified starch-based solutions and emulsions were studied by static headspace-gas chromatography. While a coalescence promoter, diglycerol ester of oleic acid decreased the release of relatively hydrophobic ethyl pentanoate and ethyl hexanoate from sodium caseinate solution due to incorporation of the flavor compounds into the vesicles formed in the solution, the other coalescence promoter, an amylase did not significantly affect the flavor release from modified starch solution. For emulsions, the release of the hydrophobic flavor compounds was generally decreased as compared to the solutions, indicating that flavor compounds used in this research tend to dissolve into the dispersed oil phase. Coalescence of oil droplets was successfully induced by the coalescence promoters under static conditions. Evaluation of the flavor release from the emulsions exhibiting coalescence revealed that oil droplet coalescence does not necessarily affect the flavor release from oil-in-water emulsions.

In order to impart emulsifying ability to gel-forming polysaccharides that have not been used as emulsifying agents, three kinds of polysaccharides, agar, curdlan, and gellan gum were converted to microgels by different gelation methods via the bottom-up and top-down approaches. We clearly demonstrated that agar and curdlan acquired the ability to emulsify an edible oil by microgel formation. Among the colloidal properties of microgel suspensions such as microstructure, particle size, zeta-potential, viscosity, and surface hydrophobicity, we pointed out the importance of particle size on the emulsifying ability of polysaccharide-based microgels. The creaming behavior of the microgel-stabilized emulsions depended on the polysaccharide types and microgel preparation methods. The emulsion stability against oil droplet coalescence was extremely high for agar and curdlan microgel-stabilized emulsions during storage in the static condition, whereas different stability was observed for both the emulsions, that is, the curdlan microgel-based ones were more resistant to dynamic forcible destabilization by centrifugation than the agar ones, which can be attributed to the surface hydrophobicity of the microgels., Food Emulsion: Microgelation turns polysaccharides into emulsifying agents Polysaccharides are widely recognized as gelling agents while rarely used alone as emulsifying agents due to their surface inactiveness. Now Kentaro Matsumiya and coworkers from Kyoto University report the microgelated polysaccharide particles can emulsify soybean oil, forming so-called microgel-based Mickering emulsions. It was found that large microgels formed by agar and curdlan exhibited better emulsifying abilities compared to small gellan gum microgels, regardless of the preparation methods. The creaming behaviors varied with the changing polysaccharide types and microgel preparation methods. The static stability was quite high for all emulsions while their dynamic stability was different, which can be attributed to the surface hydrophobicity difference. It is noteworthy that the microgelation turned surface-inactive polysaccharides into effective emulsifying agents. The low-allergenic polysaccharide food emulsions might find usage practically soon.

Obesity-induced chronic inflammation is a key factor in type 2 diabetes. A vicious cycle involving pro-inflammatory mediators between adipocytes and macrophages is a common cause of chronic inflammation in the adipose tissue. Tomato is one of the most popular vegetables and is associated with a reduced risk of diabetes. However, the molecular mechanism underlying the effect of tomato on diabetes is unclear. In this study, we focused on anti-inflammatory compounds in tomato. We found that the extract of tomato reduced plasma glucose and inflammatory markers in mice. We screened anti-inflammatory fractions in tomato using lipopolysaccharide-stimulated RAW264.7 macrophages, and active compounds were estimated by liquid chromatography-mass spectrometry over a wide range. Surprisingly, a large number of compounds including oxylipin and coumarin derivatives were estimated as anti-inflammatory compounds. Especially, 9-oxo-octadecadienoic acid and daphnetin suppressed pro-inflammatory cytokines in RAW264.7 macrophages inhibiting mitogen-activated protein kinase phosphorylation and inhibitor of kappa B α protein degradation. These findings suggest that tomato containing diverse anti-inflammatory compounds ameliorates chronic inflammation in obese adipose tissue.