Spring applied phosphorus loss with cover crops in no-till terraced field.

Cover crops (CC) can improve phosphorus (P) cycling by reducing water related P losses and contributing to P nutrition of a rotational crop. This is particularly important in claypan soils with freeze-thaw cycles in early spring in the Midwest U.S. This 4-year study (2019-2022) examined the impact of CC monoculture and mix of CC species on P losses from a fertilizer application, and determined the P balance in soil compared to no cover crop (noCC). The CC mix consisted of wheat (Triticum aestivum L.), radish (Raphanus raphanistrum subsp. Sativus), and turnip (Brassica rapa subsp. Rapa) (3xCCmix) in 2019 and 2021 before corn, and cereal rye (Secale cereale L.) was planted as monoculture before soybean in 2020 and 2022. The 3xCCmix had no effect on total phosphorus (TP) and dissolved reactive phosphorus (PO4-P) concentration or load in 2019 and 2021. Cereal rye reduced TP and PO4-P load 70% and 73%, respectively, compared to noCC. The variation in soil moisture, temperature, and net precipitation from fertilizer application until CC termination affected available soil P pools due to variability in CC species P uptake, residue decomposition, and P loss in surface water runoff. Overall, the P budget calculations showed cereal rye had 2.4 kg ha-1 greater P uptake compared to the 3xCCmix species which also reduced P loss in water and had greater differences in soil P status compared to noCC. This study highlights the benefit of CCs in reducing P loss in surface runoff and immobilizing P through plant uptake. However, these effects were minimal with 3xCCmix species and variability in crop residue decomposition from different CC species could affect overall P-soil balance.

Removal of plant endogenous proteins from tobacco leaf extract by freeze-thaw treatment for purification of recombinant proteins.

Plants are useful as a low-cost source for producing biopharmaceutical proteins. A significant hurdle in the production of recombinant proteins in plants, however, is the complicated process of removing plant-derived components. Removing endogenous plant proteins, including ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO), a major photosynthetic plant enzyme that catalyzes photosynthesis through carboxylation and oxygenation, is important for the purification of recombinant plant proteins. In particular, RuBisCO accounts for 50% of the soluble leaf protein; thus, the removal of RuBisCO is critical for the purification of recombinant proteins from plant materials. An effective conventional method, known as freeze-thaw treatment, was developed for the removal of RuBisCO from Nicotiana benthamiana, which expresses recombinant green fluorescent protein (GFP). Crude extracts or supernatants were frozen at - 30 °C. Upon thawing, most of the RuBisCO was precipitated by centrifugation without significant inactivation and/or yield reduction of GFP. Based on the proteomics analysis, using this method, RuBisCO large and small subunits were reduced to approximately 10% and 20% of those of the unfrozen supernatant solutions, respectively, without the need for specific reagents or equipment. The proteomic analysis also revealed that many ribosomal proteins were removed from the extracts. This method improves the purification process of recombinant proteins from plant materials. Prolonged freezing damaged recombinant ß-glucuronidase (GUS), suggesting that the applicability of this treatment should be carefully considered for each recombinant protein.

Comparison of freezing and heating treatment sequence on biochemical properties and flavor of swimming crabs (Portunus Trituberculatus) meat during freeze-thaw cycles.

The objective of this study was to compare the effect of freezing and heating treatment sequences on the biochemical properties and flavor of crab (Portunus trituberculatus) meat during freeze-thaw cycles. The results showed that pH, color, K and microstructure changes in the H-F group were not significant with increasing number of freeze-thaw cycles, but TVB-N values increased and WHC values decreased. However, with the increase in the number of freeze-thaw cycles, pH and WHC significantly decreased and TVB-N, L* and K values significantly increased in the C and F-H groups. Proteins were degraded in all groups, but the lower degree of degradation occurred in the H-F group. Although the total free amino acid content decreased with increasing number of freeze-thaw cycles in each group, the high content of AMP and IMP in the H-F group suggested that it still had a better flavor.

Volatilization behavior of diesel oil-water-glass bead system exposed to freeze-thaw cycles.

Volatilization plays an important role in the attenuation and redistribution of petroleum products in contaminated porous media. However, the volatilization behavior of petroleum products exposed to freeze-thaw cycles is not well understood. In this study, we investigated the volatilization behavior of diesel oil-water-glass bead systems under different freeze-thaw cycles. Low-field nuclear magnetic resonance (LF-NMR) was used to quantitatively and spatially monitor the mass loss of the diesel oil-water-glass bead system during volatilization. The mechanism of the influence of freeze-thaw cycles on volatilization in the diesel oil-water-glass bead system was analyzed. The results show that the freeze-thaw cycles have a significant effect on the volatilization rate of diesel oil and water. As the number of freeze-thaw cycles increases, the volatilization rate of diesel oil shows an overall downward trend while the volatilization rate of water shows an overall upward trend. The volatilization loss of the liquids (both diesel oil and water) is mainly due to the volatilization loss of water, indicating that water is more volatile than diesel oil in the diesel oil-water system. The spatial distribution of the diesel oil signal monitored by LF-NMR showed that diesel oil volatilizes mainly in the upper layer of the sample, associating with the preferential volatilization loss in the large pores. The lumped parameter λ related to the characteristic volatilization length LV was introduced to characterize the volatilization rate of diesel oil and water with the increase of volatilization time. For a diesel oil-water-glass bead system exposed to freeze-thaw cycles, the 1/ LV of diesel oil decreases exponentially and rapidly with increasing volatilization time, while the 1/ LV of water decreases almost linearly and slowly with increasing volatilization time. This different dependence of 1/ LV on volatilization time leads to the individual volatilization behavior of diesel oil and water.

Chitosan coating with grape peel extract: A promising coating to enhance the freeze-thaw stability of beef.

This study investigated the effect of chitosan coating with grape peel extracts (CH + GPE) on the physiochemical properties, protein and lipid oxidation, microstructure, and bacterial community diversity of beef during freeze-thaw (F-T) cycles. The results indicated that the CH + GPE groups had lower pH values, total aerobic count, total volatile base nitrogen, and thiobarbituric acid reactive substance values and better protection against color, water holding capacity, and sensory quality after five F-T cycles. The CH + GPE coating effectively inhibited beef microstructure destruction during the F-T cycles. High-throughput sequencing analysis revealed that the CH + GPE coating contributed to a decline in the bacterial diversity of beef and inhibited the growth of pathogenic bacteria. Interestingly, the CH + GPE coating affected the correlation between quality parameters and bacteria in beef. Consequently, the CH + GPE coating can be used as a novel packaging for preventing the loss of frozen meat quality due to temperature fluctuations.

Experimental study on remediation of petroleum-contaminated soil by combination of freeze-thaw and electro-osmosis.

Electro-osmosis has been well recognized as a technique for the remediation of petroleum-contaminated soil, however seasonally freezing and thawing adds the complexity of petroleum mobility in cold regions. To investigate the influence of freeze-thaw on the electroosmotic removal of petroleum and explore the enhancement of freeze-thaw on the electroosmotic remediation efficiency in remediating the petroleum-contaminated soils, a set of laboratory tests were performed in three types of treatment modes, freeze-thaw (FT), electro-osmosis (EO) and freeze-thaw combined electro-osmosis (FE). The petroleum redistributions as well as the moisture content changes after the treatments were evaluated and compared. The petroleum removal rates of the three treatments were analyzed, and the underlying mechanisms were elaborated. The results indicated that the overall efficiency of the treatment mode regarding petroleum removal from soil followed the order of FE > EO > FT, corresponding to 54%, 36% and 21% in maximum, respectively. A considerable amount of water solution with surfactant was driven into contaminated soil during FT process, but the petroleum mobilization primarily occurred inside of the specimen. A higher remediation efficiency was yield in EO mode, but the induced dehydration and cracks leaded to the dramatical depression in the efficiency in further process. It is proposed that the petroleum removal is closely related to the flow of water solution with surfactant that is favorable to the solubility and mobilization of the petroleum in soil. Thus, the water migration induced by freeze-thaw cycles substantially improved the efficiency of the electroosmotic remediation in FE mode that gave the best performance for the remediation of the petroleum-contaminated soil.

Effects of freeze-thaw cycles on methanogenic hydrocarbon degradation: Experiment and modeling.

Cold regions are warming much faster than the global average, resulting in more frequent and intense freeze-thaw cycles (FTCs) in soils. In hydrocarbon-contaminated soils, FTCs modify the biogeochemical and physical processes controlling petroleum hydrocarbon (PHC) biodegradation and the associated generation of methane (CH4) and carbon dioxide (CO2). Thus, understanding the effects of FTCs on the biodegradation of PHCs is critical for environmental risk assessment and the design of remediation strategies for contaminated soils in cold regions. In this study, we developed a diffusion-reaction model that accounts for the effects of FTCs on toluene biodegradation, including methanogenic biodegradation. The model is verified against data generated in a 215 day-long batch experiment with soil collected from a PHC contaminated site in Ontario, Canada. The fully saturated soil incubations with six different treatments were exposed to successive 4-week FTCs, with temperatures oscillating between -10 °C and +15 °C, under anoxic conditions to stimulate methanogenic biodegradation. We measured the headspace concentrations and 13C isotope compositions of CH4 and CO2 and analyzed the porewater for pH, acetate, dissolved organic and inorganic carbon, and toluene. The numerical model represents solute diffusion, volatilization, sorption, as well as a reaction network of 13 biogeochemical processes. The model successfully simulates the soil porewater and headspace concentration time series data by representing the temperature dependencies of microbial reaction and gas diffusion rates during FTCs. According to the model results, the observed increases in the headspace concentrations of CH4 and CO2 by 87% and 136%, respectively, following toluene addition are explained by toluene fermentation and subsequent methanogenesis reactions. The experiment and the numerical simulation show that methanogenic degradation is the primary toluene attenuation mechanism under the electron acceptor-limited conditions experienced by the soil samples, representing 74% of the attenuation, with sorption contributing to 11%, and evaporation contributing to 15%. Also, the model-predicted contribution of acetate-based methanogenesis to total produced CH4 agrees with that derived from the 13C isotope data. The freezing-induced soil matrix organic carbon release is considered as an important process causing DOC increase following each freezing period according to the calculations of carbon balance and SUVA index. The simulation results of a no FTC scenario indicate that, in the absence of FTCs, CO2 and CH4 generation would decrease by 29% and 26%, respectively, and that toluene would be biodegraded 23% faster than in the FTC scenario. Because our modeling approach represents the dominant processes controlling PHC biodegradation and the associated CH4 and CO2 fluxes, it can be used to analyze the sensitivity of these processes to FTC frequency and duration driven by temperature fluctuations.

Effects of freeze-thaw cycles on nutrient removal from bioretention cells.

There have been numerous summaries of the runoff purification characteristics of bioretention cells in warm climates. However, little has been done on the effects of freeze-thaw cycles (FTCs) that frequently occur in cold regions on bioretention cell performance. Three experimental columns were constructed to simulate the operation of the bioretention cell under the FTCs. The effects of FTCs on the nutrient removal efficiency of different filling bioretention cells were analyzed. The results showed that the ammonia nitrogen (NH4+-N) concentration in the effluent of the wood chip bioretention cell under the T3 conditions (WBCF) (2.35 mg/L) was significantly higher than that of the wood chip bioretention cell operating at room temperature (WBCR) (0.62 mg/L). The effluent NH4+-N concentration of aluminum sludge bioretention cell (ABCF) (0.096 mg/L) under the FTCs was lower than that of WBCF (0.91 mg/L). Under the T3 condition, the effluent nitrate nitrogen (NO3--N) and total nitrogen (TN) concentrations of WBCF (5.33 mg/L and 8.86 mg/L) were higher than those of WBCR (5 mg/L and 6.11 mg/L) at room temperature. Under FTCs conditions, both WBCF and ABCF had high NO3--N removal efficiency (up to 85.87% and 24.75%) at the initial stage of thawing of the filler, and the efficiency gradually decreased with the thawing of the filler. With the increase of FTCs, the NO3--N removal efficiency of WBCF gradually decreased (always higher than 13.6%), while the removal efficiency of ABCF fluctuated wildly (the removal efficiency was primarily negative). The total phosphorus (TP) concentration in the effluent of WBCF (0.11 mg/L) under the T3 conditions was lower than that of WBCR (0.02 mg/L) at room temperature, and the TP concentration of ABCF (0.021 mg/L) in the effluent under the FTCs was slightly lower than that of WBCF (0.031 mg/L). The FTCs have a more significant impact on removing nitrogen pollutants in runoff, but have little effect on phosphorus. Compared with aluminum sludge, wood chips are more suitable for efficient removal of nitrogen pollutants in runoff under the FTCs. The experimental conclusions can provide a reference for the construction of bioretention cells in cold regions.

Transport of plastic particles in natural porous media under freeze-thaw treatment: Effects of porous media property.

Freeze-thaw (FT) cycles would alter physical and chemical properties of soil and thus influence the transport of plastic particles (one type of emerging contaminant with great concerns). This study was designed to investigate the effects of FT treatment on the mobility of plastic particles (nanoplastics as representative) in columns packed with natural soils (i.e. loamy sand and sandy soil, quartz sand employed as comparison). We found that FT treatment of different types of porous media would induce different transport behaviors of plastic particles. Specifically, FT treatment of quartz sand did not affect plastic particles mobility. While FT treatment of loamy sand and sandy soil increased plastic particles transport. The increased pore sizes and disintegration of small soil particles from soils (the detached soil would serve as mobile vehicle for the transport of plastic particle) led to the facilitated mobility of plastic particles in two types of soils after FT treatment. The presence of preferential flow paths induced by FT treatment also drove to the enhanced mobility of plastic particles in sandy soil with FT treatment. This study clearly showed that the mobility of model plastic particles in two types of natural soils was greatly enhanced by FT treatment.

Physicochemical and Sensory Properties Colored Whey Protein-Cellulose Nanocrystal Edible Films after Freeze-Thaw Treatment.

Balancing physicochemical properties and sensory properties is one of the key points in expanding edible packaging applications. The work consisted of two parts, one was to investigate the effects of cellulose nanocrystals (CNC) on the packaging-related properties of whey protein isolate films with natural colorants (curcumin, phycocyanin, and lycopene) under freeze-thaw (FT) conditions; the other was to test oral tactility and visual sensory properties of the edible films and their overall acceptability in packed ice cream. FT treatment reduced the mechanical strength and moisture content and increased the water vapor permeability of the films, as water-phase transformation not only disrupted hydrogen bonds but also the film network structure through physical stress. The oral tactility produced by CNC and the visual effect produced by colorants could affect participants' preference for edible films. This study provides a good reference for the consumer-driven product development of packaged low-temperature products.

Ovalbumin fibril-stabilized oleogel-based Pickering emulsions improve astaxanthin bioaccessibility.

The present study aimed to enhance the bioaccessibility of hydrophobic astaxanthin (AST) by developing food-grade emulsion systems. Ovalbumin (OVA) fibrils and candelilla wax-based oleogels were prepared for the next fabrication of AST-loaded oleogel-based Pickering emulsions. The food-grade oleogel was obtained by mixing 0.7% (w/w) candelilla wax and soybean oil. The nano-scale OVA fibrils were observed by transmission electron microscope. SDS-PAGE analysis of OVA fibrils displayed the appearance of peptides with molecular weight around 10 kDa. Contact angle measurement indicated that excellent amphiphilicity endowed OVA fibrils with satisfactory Pickering emulsifier performance. The obtained oleogel-based Pickering emulsions displayed ultrastability during 90-day storage and outstanding freeze-thaw stability. Furthermore, the superiority of AST-loaded oleogel-based Pickering emulsion was further reflected in the apparently ameliorative lipolysis extent and AST bioaccessibility compared with oleogel. This work would facilitate the utilization of OVA and the development of oleogel-based Pickering emulsions with desirable nutraceutical bioaccessibility.

Impact of repeated freeze-thaw cycles environment on the allelopathic effect to Secale cereale L. seedlings.

Allelopathy, as environmental stress, plays a prominent role in stress ecotoxicity, and global warming directly increases freeze-thaw cycles (FTCs) frequency in the winter. Yet, the effect between FTCs environment and allelopathy stress is rarely known, and the interaction of allelopathy stresses lacks consideration. Here, we addressed interactions between artemisinin stress (AS) and A. trifida extract stress (AES) under Non-FTCs and FTCs environments. The results found that AS and AES had an antagonistic relation under Non-FTCs environment, while a strong synergism and cooperation under FTCs environment affect the growth and physiology in S. cereale seedlings. Besides, AS and AES under FTCs environment had more inhibition on the growth of roots and shoots, chlorophylls, photosynthetic parameters, and relative water content; while more promotion on malondialdehyde, soluble sugar, and soluble protein. Moreover, the antioxidant enzyme activities of superoxide dismutase (SOD), catalase (CAT), peroxidase (POD), and ascorbate peroxidase (APX) were increased by AS and AES, showing a good resistance of S. cereale seedlings to allelopathy stress, but FTCs environment significantly weakened this resistance. Thus, the allelopathic effect of AS and AES on S. cereale seedlings was significantly emphasized by FTCs environment.

Effects of particle size distribution of potato starch granules on rheological properties of model dough underwent multiple freezing-thawing cycles.

In order to elucidate the mechanism underlying the effect of different-sizes potato starch on dough during freeze-thaw treatment, the rheological properties, moisture distribution, secondary structure, and relative crystallinity of dough were investigated. The results showed that the storage modulus (G'), loss modulus (G″), and complex modulus (|G*|) of dough increased as a result of the freeze-thaw treatment, and the effect was more obvious as the starch granular sizes increased. The higher ß -sheet and T22 contents reflected the higher viscoelasticity and freeze-thaw sensitivity, which may be related to the higher degree expansion of amylose. In contrast, dough with small-sized starch had higher intermolecular interactions, and denser structure, lower water migration, showing that this has better resistance and higher stability. The presented mechanisms may contribute to the better understanding of the effects of freeze-thaw process on model dough properties.

Garlic and ginger essential oil-based neomycin nano-emulsions as effective and accelerated treatment for skin wounds' healing and inflammation: In-vivo and in-vitro studies.

Skin, largest organ of human, is directly exposed to environment and hence is prone to high rates of injuries and microbial infections. Over the passage of time these microbes have developed resistance to antibiotics making them ineffective especially in lower doses and hence, higher dosages or new drugs are required. The current study deals with designing of nano-emulsion (NE) formulations composed of garlic and ginger oils (0.1 %) with neomycin sulphate used in different ratios (0.001, 0.01 and 0.1 %) and combinations. The resulting NEs were characterized for droplet size (145-304 nm), zetapotential (-3.0-0.9 mV), refractive index (1.331-1.344), viscosity (1.10-1.23cP), transmittance (96-99 %), FT-IR and HPLC and found stable over a period of three months. All NEs were also found effective against both gram positive and negative bacterial strains i.e., B. spizizenii, S. aureus, E. coli and S. enterica as compared to pure neomycin sulphate (NS) used as control with highest activity recorded for NE-2 and NE-4 against all strains showing zone of inhibition in range of 22-30 mm and 21-19 mm, respectively. NEs were also tested using rabbit skin excision wound model which potentiates that all the NEs resulted in early recovery with 86-100 % wound healing achieved in 9 days as compared to NS ointment (71 %). The studies confirmed that essential oils when used in combination with traditional drug can lead to much higher efficacies as compared to pure drugs.

Durability Properties of Concrete Supplemented with Recycled CRT Glass as Cementitious Material.

This paper presents the testing of the durability of concrete where a part of cement was replaced with ground panel cathode ray tube glass (CRT) finer than 63 µm. The percentage of cement replaced with glass is 5%, 10%, 15%, 20%, and 35%, by mass. The highest percent share of mineral admixtures in CEM II (Portland-composiste cement) cement was chosen as the top limit of replacement of cement with glass. In terms of the concrete durability, the following tests are performed: freeze-thaw resistance, freeze-thaw resistance with de-icing salts-scaling, resistance to wear according to the Böhme test, sulfate attack resistance, and resistance to penetration of water under pressure. A compressive strength test is performed, and shrinkage of concrete is monitored. In order to determine the microstructure of concrete, SEM (Scanning Electron Microscopy) and EDS (Energy Dispersive X-ray Spectroscopy) analyses were performed. The obtained research results indicate that the replacement of a part of cement with finely ground CRT glass up to 15% by mass has a positive effect on the compressive strength of concrete in terms of its increase without compromising the durability of concrete. The results obtained by experimental testing unequivocally show that concrete mixtures made with partial replacement (up to 15%) of cement with finely ground CRT glass have the same freeze-thaw resistance, resistance to freeze/thaw with de-icing salt, resistance to wear by abrasion, and resistance to sulfate attack as the reference concrete. In terms of environmental protection, the use of CRT glass as a component for making concrete is also very significant.

Effects of concentrations, temperature, pH and co-solutes on the rheological properties of mucilage from Dioscorea opposita Thunb. and its antioxidant activity.

The mucilage from Dioscorea opposita (DOM) dispersions presented shear-thinning behaviour that well fitted to the Power Law model. The effects of different concentrations (2%-10% w/v), temperatures (25-80 °C), pH (3.0-9.0), freeze-thaw conditions (thawed at 25 °C and 4 °C), co-salts (KCl and CaCl2) and co-sugars (sucrose, fructose and mannose) on the rheological properties were investigated. Generally, higher concentrations, neutral pH, Ca2+ and sugars increased the viscosity of DOM, while increasing temperature (25-65 °C) had opposite effects. The results suggested that cross-linked networks exist in DOM, and viscosity changes may be related to the ionisation of carboxyl groups, structural changes and enhancement/reduction of molecular interactions. Particularly, Ca2+ could interact with uronic acids of two or more polysaccharide molecules, modify the network-structure through cross-linking with carboxyl groups, and enhance the stronger carboxylate-cation2+-carboxylate interactions. Therefore, DOM is suitable for food applications as thickening or gelling agents in aqueous solutions.

Hemin from porcine blood effectively stabilized color appearance and odor of prepared pork chops upon repeated freeze-thaw cycles.

This study was designed to evaluate changes in color following pork chop supplementation with porcine hemin, astaxanthin and paprika red in response to repeated freeze-thaw processes. Surface color analyses revealed that hemin significantly enhanced the appearance of the pork chops (P < 0.05), and the coloring efficiency of 0.10% hemin was similar to that of 0.20% astaxanthin and 0.08% paprika red. Sensory evaluations conducted on both raw and fried chops showed that hemin and astaxanthin significantly enhanced the overall acceptability of the chops before and after cooking. The color stability of the pork chops was also evaluated, and the results suggested that the hemin-colored chops were the most stable among the three, upon repeated freeze-thaw cycles. The electronic nose showed that the odor of the hemin-colored samples after 0, 3, and 7 freeze-thaw cycles was better than that of the other two groups. In conclusion, hemin may be a superior supplement for the large scale preparation of prepared pork chop.

The effect of astaxanthin supplementation on the post-thaw quality of dog semen.

Astaxanthin is a member of the carotenoid family well known for its anti-cancer, anti-diabetic, anti-inflammatory and antioxidant nature. This study was designed to investigate the effects of astaxanthin supplementation of the extender (buffer 2) on post-thaw dog semen quality. Semen from four healthy dogs was collected by digital manipulation twice a week. The ejaculates were pooled, washed, divided into four equal aliquots, diluted with the extender supplemented with different concentrations of astaxanthin (0, 0.5, 1 and 2 µM) and cryopreserved. The results showed that 1 µM astaxanthin was the optimum concentration that led to significantly higher (p < .05) post-thaw motility, kinematic parameters and viability than the other groups. In comparison with the control group, sperm samples supplemented with 1 µM astaxanthin showed significantly higher (p < .05) sperm counts with intact membranes (55.7 ± 0.6% vs. 51.3 ± 0.9%), intact acrosome (58.4 ± 0.7% vs. 53.5 ± 0.6%), active mitochondria (54.9 ± 0.5% vs. 42.6 ± 0.6%) and normal chromatin (67.6 ± 0.9% vs. 61.7 ± 0.6%). Furthermore, astaxanthin-supplemented samples showed significantly lower expression levels (p < .05) of pro-apoptotic (BAX), oxidative induced DNA damage repair (OGG1), oxidative stress-related (ROMO1) genes and higher expression levels of anti-apoptotic (BCL2), and sperm acrosome-associated (SPACA3) genes compared to the control. Thus, supplementation of 1 µM astaxanthin in semen extender results in improved freeze-thaw sperm quality of the dog.

Effect of diacylglycerol interfacial crystallization on the physical stability of water-in-oil emulsions.

The influence of diacylglycerol (DAG) combined with polyglycerol polyricinoleate (PGPR) on the stability of water-in-oil (W/O) emulsions containing hydrogenated palm oil (HPO) was studied. Polarized light microscope revealed that DAG promoted HPO to crystallize at the water-oil interface, providing the combination of Pickering and network stabilization effects. It was proposed that the molecular compatibility of fatty acids in DAG with HPO accounted for the promotional effect. The interfacial crystallization of DAG together with the surface activity of PGPR led to the formation of emulsions with uniform small droplets and high freeze-thaw stability. Further exploration of physical properties indicated that the combination of DAG and PGPR dramatically improved the emulsion's viscoelasticity and obtained a larger deformation yield. Water droplets in DAG-based emulsions acted as active fillers to improve the network rigidity. Therefore, DAG is a promising material to be used as emulsifier to enhance the physical stability of W/O emulsions.

Effect of freeze-thaw cycles pretreatment on the vacuum freeze-drying process and physicochemical properties of the dried garlic slices.

Freeze-thaw cycles (FTC) pretreatment was employed before the vacuum freeze-drying of garlic slices, aimed at improving the drying process and the quality of the end product. Cell viability, water status, internal structure, flavor, chemical composition and thermogravimetric of garlic samples were evaluated. The results indicated that FTC pretreatment reduced the drying time (22.22%-33.33%) and the energy consumption (14.25%-15.50%), owing to the water loss, the increase in free water, and the formation of porous structures. The FTC pretreatment improved thermal stability, flavor and chemical composition content of dried products. The antioxidant activity of polysaccharides extracted from FTC pretreated dried products was higher than that of the unpretreated dried product due to the reduction in polysaccharide molecular weight. This research could pave a route for future production of dried garlic slices having good quality by using the FTC pretreatment, with lower energy consumption and shorter drying time.