Low Temperature Storage Conditions Research Articles

Effects of sequential combination of cryogenic immersion freezing and ultra-cold frozen storage on the quality of Korean white kimchi

This study aimed to assess the effects of three different freezing techniques — cold room freezing (CRF; −20 °C), air-blast freezing (ABF; −70 °C), and cryogenic immersion freezing (CIF; −70 °C) — on the microstructure and physicochemical properties of Korean white kimchi (KWK) during frozen storage at −20 °C and − 45 °C for 8 weeks. CIF-treated KWK exhibited a higher freezing rate and after ultra-cold (UC; −45 °C) frozen storage, it showed a greater number and smaller diameter and area of ice crystals than CRF- and ABF-treated KWK. Drip loss was reduced and CIE color changes were delayed in KWK under UC frozen storage. The pH, titratable acidity, and reducing sugar content of frozen KWK remained unaffected by the freezing method, storage temperature, or duration. Thus, CIF combined with UC frozen storage preserves the physicochemical quality of KWK with minimal histological damage during long-term storage. Industrial relevanceIn the kimchi industry, where the shelf life of commercial products is often constrained by successive fermentation under low-temperature storage and distribution conditions, introducing frozen kimchi is a promising solution to reduce waste of overripe kimchi in the supply chain. This study highlights the effectiveness of combining CIF and UC frozen storage methods to minimize the damage caused by freezing in kimchi. This innovative technology provides a practical means for streamlining freezing processes, saving operational time, and ensuring kimchi quality during long-term storage and distribution.

Effect of different storage conditions on dimensional accuracy of 3D-printed dental models.

The objective was to determine the accuracy of 3D-printed dental models subjected to different storage conditions using six different material and printer combinations. Three completely dentate models were designed using dental CAD software (3Shape Dental System). A horseshoe-shaped solid base with a posterior horizontal bar was used. The models were printed in a horizontal direction against the building platform without support. The models were printed using six printers with the corresponding recommended resin material: Carbon M2 (DPR10), HeyGears A2D4K (Model HP UV2.0), Stratasys J5 (MED610), Stratasys Origin One (DM200), Envision One (E-Model LightDLP), and Asiga Pro4K (VeriModel) with a standard layer thickness of 50 μm. All printed models underwent scanning using a laboratory scanner (Sirona inEOS X5) after printing. Subsequently, the models were randomly assigned into three groups of storage conditions, LT: cold environment (4±1°C), HT: hot and dry environment (50±2°C), and RT: room temperature (25±2°C) serving as the control. Each group was kept under the designated condition and was scanned at 1, 2, 3, 4, and 8 weeks. The total number of models (N) was 72, with 6 printers producing 12 models per printer for 3 storage conditions, resulting in 4 models for each storage condition and each printer. The generated STL files were imported into a 3D inspection software for comparison with the original STL files. In-tolerance percentage, the deviation RMS, trueness, and precision were obtained and analyzed with least square mean linear regression using JMP Pro 15 to identify the significant effects (α = 0.05). The in-tolerance percentage as-printed was significantly different among different printers. Significant dimension deviations were observed after the first week of storage at HT and with subsequent weeks of storage. RT and LT did not show significant dimensional changes. Models printed with Carbon M2 showed the highest in-tolerance percentages compared to the other printers. The model deviations were affected by storage conditions and the printer used, with high-temperature storage showed least stability compared to low and room temperatures. No significant difference was observed between low and room temperature storage conditions. The Carbon M2 printer showed the highest accuracy among all printers tested. The region had a significant effect on the deviation measured, with the abutment body showing the least deviation. Among the 3D printers evaluated, A2D4K by HeyGears and Carbon M2 printers demonstrated the highest accuracy in terms of both precision and trueness.

Influence of Packaging Materials and Size on Shelf Life and Quality of White Button Mushroom during Storage

Background: Because of porous fruit body, high moisture content and extremely high respiration rate, the postharvest shelf life of button mushroom is a bottleneck in the mushroom industry as very high losses are recorded during transportation and marketing if the produce is not handled properly. Methods: NBS-5 strain of white button mushroom was treated with 0.05% potassium meta-bisulphite (KMS) followed by packing in 200, 400, 600, 800 and 1000 g capacity polyethylene (PE) and polypropylene (PP) bags of 150 gauge along with 0.01% vents. Dipping in water and packing in 200 g capacity bags was used as control. The packed mushrooms were stored at ambient (24-25°C and 58-62% RH) and low (4-6°C and 80-82% RH) temperature. Result: A significant increase in PLW (%) was recorded in all the treatments both at ambient and low temperature during storage but the increase was faster at room than refrigerated conditions. The white button mushroom in PE had a shelf-life of 7 and 16 days whereas it was 3 and 7 days, respectively, at ambient and low temperature storage conditions in control. A significant reduction in protein, sugars and phenols was recorded whereas polyphenol oxidase (PPO) increased notably during storage. Pack sizes of 200 and 400 g had an edge over 600, 800 and 1000 g with higher shelf-life at both storage conditions. PE packing was found comparatively better for extension of shelf-life compared to PP. The overall acceptability of button mushroom was also found better in 200 g and 400 g packing. The study revealed that the postharvest shelf-life of white button mushroom var. NBS-5 can be extended up to 16 days by packing in 200 and 400 g packs of PE stored at low temperature after pre-treatment of KMS.

Preparation of Cubosomes with Improved Colloidal and Structural Stability Using a Gemini Surfactant.

Cubosomes are nanoparticles with bicontinuous cubic internal nanostructures that have been considered for use in drug delivery systems (DDS). However, their low structural stability is a crucial concern for medical applications. Herein, we investigated the use of a gemini surfactant, sodium dilauramidoglutamide lysine (DLGL), which is composed of two monomeric surfactants linked with a spacer to improve the structural stability of cubosomes prepared with phytantriol (PHY). Uniform nanosuspensions comprising a specific mixing ratio of DLGL and PHY in water prepared via ultrasonication were confirmed by using dynamic light scattering. Small-angle X-ray scattering and cryo-transmission electron microscopy revealed the formation of Pn3̅m cubosomes in a range of DLGL/PHY solid ratios between 1 and 3% w/w. By contrast, cubosome formation was not observed at DLGL/PHY solid ratios of 5% w/w or higher, suggesting that excess DLGL interfered with cubosome formation and caused them to transform into small unilamellar vesicles. The addition of phosphate-buffered saline to the nanosuspension caused aggregation when the solid ratio of DLGL/PHY was less than 5% w/w. However, Im3̅m cubosomes were obtained at solid ratios of DLGL/PHY of 6, 7.5, and 10% w/w. The lattice parameters of the Pn3̅m and Im3̅m cubosomes were approximately 7 and 11-13 nm, respectively. The lattice parameters of Im3̅m cubosomes were affected by the concentration of DLGL. Pn3̅m cubosomes were surprisingly stable for 4 weeks at both 25 and 5 °C. In conclusion, DLGL, a gemini surfactant, was found to act as a new stabilizer for PHY cubosomes at specific concentrations. Cubosomes composed of DLGL are stable under low-temperature storage conditions, such as in refrigerators, making them a viable option for heat-sensitive DDS.

Allergy patient-specific IgE antibody shows significantly stability during 3 months of storage at multiple temperatures from -80 to 25°C.

The detection of allergen-specific IgE antibodies is an important biomarker for the diagnosis and treatment monitoring of allergic diseases. And the pre-analytical phase is an important part of the overall quality of the laboratory. In this study, 44 patients with allergic diseases (including 23 patients with allergic rhinitis, 12 patients with allergic rhinitis and asthma, and 9 patients with allergic dermatitis) were included in the outpatient center of the Department of Allergy, the First Affiliated Hospital of Guangzhou Medical University. We mixed the serums of the above 44 patients (approximately 0.8 ml of serum volume per patient) into a large volume of serum pool (about 35 ml in total) and divided into 26 parts. And 26 serum samples were stored at 4 different temperatures for 90 days to observe the stability of sIgE antibodies to 16 allergens in serum. The results show that serum sIgE antibody titers in patients with allergic diseases show significant stability during 90 days of storage, even at room temperature. Good stability even after up to 10 freeze-thaw cycles under low temperature storage conditions.

Effects of storage conditions on the molecular-level composition of organic aerosol particles

Abstract. A significant fraction of atmospheric aerosol particles, which affect both the Earth's climate and human health, can be attributed to organic compounds and especially to secondary organic aerosol (SOA). To better understand the sources and processes generating organic aerosol particles, detailed chemical characterization is necessary, and particles are often collected onto filters and subsequently analyzed by liquid chromatography–mass spectrometry (LC–MS). A downside of such offline analysis techniques is the uncertainty regarding artifactual changes in composition occurring during sample collection, storage, extraction and analysis. The goal of this work was to characterize how storage conditions and storage time can affect the chemical composition of SOA generated from β-pinene and naphthalene, as well as from urban atmospheric aerosol samples. SOA samples were produced in the laboratory using an aerosol flow tube and were collected onto PTFE filters, whereas ambient samples were collected onto quartz filters with a high-volume air sampler. To characterize temporal changes in SOA composition, all samples were extracted and analyzed immediately after collection but were also stored as aqueous extracts or as filters for 24 h and up to 4 weeks at three different temperatures of +20, −20 or −80 ∘C in order to assess whether a lower storage temperature would be favorable. Analysis was conducted using ultra-high-performance liquid chromatography–high-resolution mass spectrometry (UHPLC–HRMS). Both principal component analysis (PCA) and time series of selected compounds were analyzed to identify the compositional changes over time. We show that the chemical composition of organic aerosols remained stable during low-temperature storage conditions, while storage at room temperature led to significant changes over time, even at short storage times of only 1 d. This indicates that it is necessary to freeze samples immediately after collection, and this requirement is especially important when automated ambient sampling devices are used where filters might be stored in the device for several days before being transferred to a laboratory.

Retaining overall quality of fresh figs by postharvest hexanal vapor treatment during cold storage

Figs (Ficus carica L.) are rich in nutrients, but their rapid metabolic changes due to the climacteric respiratory behavior during ripening make them a highly perishable commodity, which leads to quick deterioration in quality and a shortening storage period. In this study, the influence of hexanal vapor (0.01% or 0.02% introduced as HEX-I and HEX-II, respectively) treatments were evaluated on ‘Abbas’ figs during storage at 4 ± 1 °C, 90% RH for 18 d. Both concentrations of hexanal treatments delay senescence while retaining quality, as indicated by a greener fruit peel (lower a* value), higher pulp firmness, membrane stability index (MSI), titratable acidity (TA), and lower total soluble solids (TSS), weight loss, and TSS/acid ratio than the untreated fruit. Total content of phenol (TPC), flavonoid (TFC), and vitamin C, as well as free radical scavenging capacity (FRSC) were higher in hexanal-treated fruit as compared to untreated fruit. All hexanal-treated fruit had lower hydrolytic enzyme and polyphenoloxidase (PPO) activity but higher catalase (CAT) and peroxidase activity (POD) than the control. Decay incidence (DI) and microbial counts (MC) (mold and yeast) increased during storage but were suppressed in all treated fruit. Though both concentrations of hexanal were effective in retaining quality and delaying senescence, the higher concentration was more effective than the lower one. Therefore, hexanal vapor at 0.02% can be used to preserve quality and prolong the storage period of ‘Abbas’ figs under low-temperature storage conditions.

Low temperatures inhibit the pectin degradation of ‘Docteur Jules Guyot’ pear (Pyrus communis L.)

The most remarkable characteristic of European pears is extremely perishable and difficult to store after postharvest softening. Low-temperature storage is one of the most commonly used methods to prolong the shelf life of European pears. However, the regulatory mechanism of the low-temperature delay of the softening of European pears is still unclear. In this study, the fruit firmness, pectin polysaccharide content, pectin-degrading enzyme activity, and pectin degradation gene expression of ‘Docteur Jules Guyot’ pears under low temperature (LT) and room temperature (RT) were analyzed. It was found that water-soluble pectin (WSP) was significantly negatively correlated with fruit flesh firmness, and the activities of several pectin-degrading enzymes were inhibited under LT storage conditions. In addition, it was also found that the gene expression patterns of PcPME2, PcPME3, PcPG1, PcPG2, PcPL, PcGAL1, PcGAL2, PcGAL4, and PcARF1 were inhibited by LT. The C-repeat binding factors PcCBF1 and PcCBF2 were also inhibited by long-term LT storage. Correlation analysis showed that the expression of PcCBFs was positively correlated with pectin-degradation enzyme genes, and we found that the promoters of many pectin-degradation enzyme genes contain the CRT/DRE motif, which CBF can directly bind. Therefore, it is speculated that long-term low-temperature conditions inhibit pectin degradation through PcCBFs.

Energy and exergy performance evaluation of a novel low-temperature physical energy storage system consisting of compressed CO2 energy storage and Kalina cycle

To improve the overall performance of the Compressed CO2 Energy Storage (CCES) system under low-temperature thermal energy storage conditions, this paper proposed a novel low-temperature physical energy storage system consisting of CCES and Kalina cycle. The thermal energy storage temperature was controlled below 200 °C, and the Kalina cycle was used to optimize the reuse of the stored thermal energy. A thermodynamic model of the integrated system was constructed, and the system performance was analyzed from the energy and exergy perspectives. Several evaluation indicators, such as system exergy efficiency (SEE), round trip efficiency (RTE), system energy density (SED), Kalina exergy efficiency (KEE), and Kalina energy efficiency (KEnE), were defined to evaluate system performance. In addition, the influences of several core parameters (e.g., split ratio (r), storage pressure (ps), turbine efficiency (te), pinch point temperature difference (pt) of heat exchangers, and ambient temperature (T0)) on the system performance were analyzed. The results of the base condition showed that SEE, RTE, SED, KEE, and KEnE were 58.17 %, 59.38 %, 6.32 kWh/m3, 38.62 %, and 8.64 %, respectively. The exergy destruction in heat exchanger 3 was the largest, accounting for 71.7 % of total exergy destruction. The sensitivity analysis results showed that increasing r could increase the SEE of the system, increasing ps could lead to a decrease in the RTE of the system, and increasing T0 could cause the RTE and SED to increase. The increase in te could improve all evaluation indices, while the increase in pt could reduce the system's overall performance. This study provides a new solution for the integrated application and optimal design of CCES systems under low-temperature thermal energy storage conditions.

Assessment of Aflatoxin Contamination in Maize and Groundnuts during Storage in Giwa Community, Kaduna State Nigeria

Contamination of food and feed by aflatoxins has become a worldwide cause of public health concern due to its significant impact on human health and crop market value. The present study aimed to assess the aflatoxin contents of maize and groundnut from stores and warehouses in the Giwa community, Kaduna State, Nigeria. A total of ninety (90) grain samples of maize and groundnut were collected between October to December 2020 and analyzed for total aflatoxins using Enzyme-Linked Immuno Sorbent Assay (ELISA). Eighty-four 84(93.3%) of the samples had detectable aflatoxin levels (0.2-9.8ppb), while six 6(6.7%) had none. There was no significant difference (P>0.05) in the mean total aflatoxin content of the grains from stores, warehouses and household foodstuff samples. This could be attributed to agricultural practices and low temperature and humidity storage conditions, which were the same for all the stored grains. Overall, aflatoxin concentrations of the grain samples were within the acceptable limit (10ppb for maize and 15ppb for groundnut) for food safety set by NAFDAC. However, there could be further contamination during storage, particularly when temperature rises and humidity increases. Hence, improved storage conditions and monitoring of grain before sale are recommended to avoid contamination during storage and to ensure a healthy and safe food supply along the trade chain and to the consumers.

Effect of low temperature storage conditions on the viability of microalgae Chlorococcum dissectum

Chlorococcum dissectum Korshikov, 1953 is a unicellular freshwater green alga capable of accumulating and depositing lipids in cells. Regardless of their origin and taxonomic classification, biotechnologically important microorganisms and cell lines are biological resources that are used to produce various products. The aim of the work was to determine the effect of low-temperature storage conditions on the alga viability. The temperatures used were as follows: –18, –40, –70, and –196°C. An ordinary household freezer was used to provide –18°C. Cooling to –40 and –70°C was carried out with uncontrolled cooling rates by placing the cryotubes directly into the freezers or using a Mr. Frosty freezing container, which provides a temperature decrease rate of 1 deg/min. Freezing to –196°C was carried out by direct immersion of cryotubes in liquid nitrogen and two-stage cooling at 1 and 20 deg/min to –40°C with subsequent transfer to a cryostorage. The viability of C. dissectum was determined by counting the colonies formed on BG-11 agarized nutrient medium. It was found that the cells completely lost their viability after freezing to –18°C and storage for two days. Cryopreservation to –196°C for all studied variants and uncontrolled cooling rate to –40 and –70°C, as well as further storage of such samples at these temperatures, led to significant or complete loss of their viability. Cooling in a Mr. Frosty freezer container to –40 and –70°C did not affect the ability of cells to grow. Moreover, storing C. dissectum at –40°C did not cause a significant loss of viability throughout the study period, and its storage at –70°C did not change the viability index at all. The obtained results showed that the controlled cooling and the use of freezers at –40°C and –70°C, respectively, are promising for medium-term and long-term storage of C. dissectum suspension culture. To increase the viability of samples after cooling to liquid nitrogen temperature, it is necessary to develop cryopreservation modes using cryoprotectants.

Investigation of lactic acid bacterial profiles in commercial rice wine and their effect on metabolites during low-temperature storage

Makgeolli, the traditional Korean rice wine, is generally considered to contain lactic acid bacteria (LAB) despite its bacterial inoculation-free brewing process. The existence of LAB in makgeolli often presents inconsistent trends in microbial profiles and cell numbers. Therefore, to establish LAB-related insights, 94 commercial non-pasteurized products were collected and microbial communities and metabolites were analyzed using 16S rRNA amplicon sequencing and GC–MS, respectively. All samples contained various LAB genera and species, with an average viable cell number of 5.61 log CFU/mL. Overall, 10 LAB genera and 25 LAB species were detected; the most abundant and frequent LAB genus was Lactobacillus. There was no significant change in the LAB composition profile or lactic acid content during low-temperature storage, indicating the presence of LAB did not significantly affect the quality of makgeolli under low-temperature storage conditions. Overall, this study contributes to understand the microbial profile and role of LAB in makgeolli.

Raw Milk for Provolone Valpadana PDO Cheese: Impact of Modified Cold Storage Conditions on the Composition of the Bacterial Biota

The raw milk for production of long-ripened, spicy type, Provolone Valpadana (PV) PDO cheese must be stored, refrigerated, and processed within 60 h from the first milking, according to European and Consortium regulations. Low-temperature storage conditions preserve the hygienic quality, but also reduce the diversity and content of dairy microbiota, which is important to define the characteristics and quality of raw milk cheeses. Eleven bulk, raw milk samples were stored, at laboratory level, under two different time/temperature conditions (i.e., 10 °C or 12 °C for 15 h, then cooled to 4 °C for 45 h). The count of different bacterial groups and the diversity of bacterial communities were determined before and after storage by culture-dependent and DNA metabarcoding methods, respectively. The two-step cold storage conditions increased the mesophilic, psychrotrophic, lipolytic, and proteolytic bacterial load, without affecting the hygienic quality of milk. Among the 66 dominant and 161 subdominant taxa retrieved by DNA metabarcoding, Acinetobacter, Pseudomonas, and the lactic acid bacteria belonging to the genera Lactococcus and Streptococcus were present in almost all the raw milk samples, and their relative abundance was positively related with the total bacterial count. The storage conditions tested could be considered for eventual application in long-ripened PV cheese production to rationalize storage, transfer, and processing of raw milk.

Analytical models for predicting the behavior of the Fukushima fuel debris during laboratory tests and long-term storage

The results of the laboratory-based aging experiments with synthesized fuel debris (simulated corium–concrete compound) are discussed. The tests included dynamic (i.e. with periodic solution renewal) experiments with monoliths of the synthesized fuel debris. At the time scale of the experiments, at a temperature of 25 °C, no evolution in the composition of the leachate debris was observed. At the elevated temperature regime, T = 50, 90 and 120 °C and pH ranges from acid to alkaline condition (pH=4, pH=7, and pH=9), the major chemistry changes that occurs during the leaching were the increase of Si, Al and Ca, as structural elements of the concrete fraction of the debris, while the major elements of the melted fuel matrix, U and Zr, were found in the leachate in trace quantities. The release of Si, Al and Ca, was proved to be non-congruent (Ca and Al releases much faster compared to Si) that corresponds to the basic concept of multioxide silicate dissolution. Such system behavior as well as a number of the chemical interactions between the elements limits the classical chemical thermodynamic and kinetic methods and forced us to use a simplified, semi-empirical, effective approach. The component release rates measured in batch tests were fitted to a proposed diffusion and kinetics model which accounts also for the various pH and temperature conditions. Long-term prediction of the glassy phase dissolution and surface enrichment with a poorly dissolved fuel fraction, (U, Zr)O2, is based on a first-order kinetic model inherited the significant properties of the more detailed lab-scale model. To evaluate the growth kinetics of (U, Zr)O2 layer on debris surface, dissolution rate coefficients from the aging laboratory experiments were used. These coefficients calculated for high-temperature (T = 50 and 90 °C) surface reactions, were extrapolated to low-temperature debris storage conditions via the Arrhenius equation. It was shown, that the aging of debris in a water environment at room temperature and neutral pH under no-flow storage conditions results in the density accumulation of the (U, Zr)O2 product up to several g/m2. At the alkaline condition (pH=9) these values increase about five times. The further rise in temperature results in further intensification of the silica leaching process that may dramatically increase the accumulation amount of (U, Zr)O2.

Effects of curcumin‐based photodynamic treatment combined with low‐temperature storage on shelf life and purine content of Litopenaeus vannamei

In this study, the effects of photodynamic treatment on the shelf life and purine content of Litopenaeus vannamei under low-temperature storage conditions were investigated. Indicators of shelf life were detected to evaluate the shelf life, and the change of purine content during storage detected by HPLC. The results showed that compared with cold storage, the shelf life of shrimp was extended from 3 days to 8 days with the treatment of microcrystalline storage. Moreover, the shelf life of shrimp was extended to 12 days when stored with the photodynamic treatment combined with microcrystalline storage (PDT + MT). The content of hypoxanthine decreased significantly after 24 h storage, which may be related to the inhibition of 5′-NT, PNP, ADA, and XOD activities. This study provided scientific support for the popularization and application of photodynamic technology in the storage of shrimp. Novelty impact statement Photodynamic technology is helpful to prolong the shelf life of shrimp during low-temperature. Photodynamic combined with low-temperature can affect purine content by affecting purine metabolism enzymes.

Ppb-level H2S gas sensor based on CuNi-MOFs derivatives for meat freshness detection at low temperature environment

H2S is usually used as one of the landmark gases for meat freshness detection under low temperature storage conditions. In this paper, the NiO-doped CuO composite derived from MOFs was synthesized by a low temperature (−25 ℃) precursor hydrothermal and sintering procedure for H2S detection. The influence of precursor solution temperature and sintering temperature on the structure of MOFs derivatives were discussed by SEM, TEM, and XRD characterization. The hydrothermal method of low-temperature precursor has guiding significance in improving the gas response performance of MOFs/MOFs derivatives. The sensor based on NiO-doped CuO composites derived from MOFs exhibited a ppb-level response to H2S gas. The sensor response is 106 % to 50 ppb H2S. Meanwhile, the sensor has good selectivity, and the response and recovery time are 115 s and 251 s, respectively. The low temperature precursor hydrothermal method directly affected the morphology and structure of MOFs derivatives by regulating the kinetics for MOFs nucleation and crystal growth, obtains more active adsorption sites. In addition, the composite has good sensing performance for H2S at the ambient temperature of 4 ℃ and −18 ℃, which verified the effectiveness for the detection of meat spoilage under a low temperature storage. Furthermore, the sensor based on NiO-doped CuO composites is a good candidate for H2S gas detection in meat freshness evaluation. Finally, an integrated circuit detection system was designed to detect H2S gas at different ambient temperatures. This work provides a new idea for meat freshness detection in a cold storage environment.

Studi Bahan Kemasan terhadap Viabilitas Benih Kedelai (Glycine max [L.] Merril) Pascasimpan Dua Belas Bulan di Ruang Simpan Suhu Rendah

Soybean is a commodity that is a source of vegetable protein that is easily obtained at a low price. The factor that affects low soybean productivity in Indonesia is the lack of use of quality seeds by farmers. Efforts to maintain the shelf life of soybean seeds can be done by using good packaging materials. The purpose of this study was to determine the effect of packaging materials that have different characteristics under low temperature storage conditions on the viability of soybean seeds after twelve months of storage. This research was carried out at the Seed and Plant Breeding Laboratory, Faculty, Agriculture, University of Lampung from October 2019 to June 2020. The treatment design was a single and unstructured factor, namely packaging material (b). The treatment of packaging materials consisted of aluminum foil (b1), polyethylene (b2), polypropylene (b3), brown envelope paper (b4), ordinary plastic (b5), calico fabric (b6). The packaging materials for six treatments were arranged in a randomized block design (RAK) with four replications. The results of this study showed that the viability of seeds was high in aluminum foil, polyethylene, polypropylene, ordinary plastic, envelope paper, and calico packaging materials in low temperature storage in an air-conditioned storage room after twelve months of storage. Twelve months post-stored seed viability was indicated by the germination rate of 87.48%; maximum growth potential of 96.25%; germination speed 30.96%; strong normal sprouts 81.19%; hypocotyl length 11.99 cm; dry weight of normal sprouts 31.82 mg; water content 7.30%; and electrical conductivity of 244.96 S/cm. Key words: viability, soybean seed, storage, packaging material, low temperature

Pre-harvest Application of Calcium Maintained Fruit Quality in Cold Stored Plum

: An experiment was conducted to study the influence of pre-harvest applications of different concentrations of calcium nitrate on various physico-chemical parameters of plum ( L.) Satluj Purple under cold storage conditions. Uniform and healthy plants Prunus salicina cv. of plum Satluj Purple were sprayed with calcium nitrate (1.0, 1.5 and 2.0 %) in 2 and 3 week of April and control plants were water sprayed cv. nd rd only. Fruits from both treated and control plants were harvested at colour break stage, and then stored at low temperature conditions (0–1 °C and 90–95 % RH) for 35 days. Evaluation of different physico-chemical parameters were made on 0 day and after 7, 14, 21, 28 and 35 days of storage. The results revealed that two sprays of Ca(NO ) @ 2.0 % retained maximum pulp: stone (15.37), total soluble solids (12.93 %), 3 2 titratable acidity (0.69 %), reducing (6.52 %) & non-reducing sugars (2.64 %) and total phenolics content (101.19 mg 100g ) at the end of -1storage. The fruits treated with two sprays of Ca(NO ) @ 2.0 % were effective in maintaining the quality of fruits without any spoilage up to 35 3 2 days under low temperature storage conditions.

Improvement of drying efficiency and quality attributes of blueberries using innovative far-infrared radiation heating assisted pulsed vacuum drying (FIR-PVD)

A new drying technology, far-infrared radiation heating assisted pulsed vacuum drying (FIR-PVD) was applied to process blueberries. Influences of drying temperature, vacuum pressure duration (VPD), and ambient pressure duration (APD) on drying characteristics and quality attributes of blueberries were investigated under FIR-PVD. Results showed that drying temperature, APD, and VPD had significant influence on drying time and quality attributes of dried blueberries expect for color and cohesiveness. Compared to hot air dried blueberries, FIR-PVD seriously damaged the cellular walls of blueberries during drying at 65 °C. The highest total phenolics (TP) and total monomeric anthocyanins (TMA) contents of dried blueberries were obtained at 65 °C with pulsed ratio of 15 min: 4 min and 15 min: 2 min, respectively. The FIR-PVD products obtained lower color difference, better mechanical properties and rehydration performance and maintained higher antioxidant capacity by shortening drying time, reducing exposure to oxygen, and modifying the microstructure compared to hot air drying. Industrial relevanceBlueberry is a popular function fruit around the world. With high moisture content and tender tissue, fresh blueberry is very susceptible to microbial infection even under low temperature storage conditions. Drying is a good alternative to extend the shelf life and increase the availability of fresh blueberries. However, the existence of waxy hydrophobic layer covered the surface of blueberries inhibits moisture diffusion during drying. Chemical dipping and thermal blanching pretreatments were usually used to reduce the influence of skin hydrophobicity and promote moisture diffusion. Nevertheless, the chemical additive residue leads to food safety risk and it's a big challenge to deal with the corrosive waste chemical solutions, while thermal blanching resulted a high loss of bioactive compounds. FIR-PVD is a recent developed emerging drying technology to process berries with waxy layer beyond pretreatments. Results indicated that FIR-PVD is a very promising technology for processing blueberries with the improvement of drying efficiency and quality attributes.

Effect of different closure types and storage temperatures on the color and sensory characteristics development of Argentinian Torrontes Riojano white wines aged in bottles

During aging, most bottled white wines lose their distinctive organoleptic characteristics according to their storage conditions (closure, temperature, time). However, the effect of these factors on organoleptic characteristics of Torrontes Riojano wines (TRw) has not been studied yet. This study aimed at evaluating the combined effect of closure type and storage temperature on the organoleptic properties development of TRw over a 18-month aging period, during which wine was bottled with natural (C) and synthetic (SyC) corks, and screwcaps (SC). Bottles were kept 18 months in thermostatized chambers (15 °C; 25 °C). At different aging times, consumed oxygen (CO), SO2, total phenols (TP), color, and sensory properties were evaluated. CO, TP, and browning index evolutions depended on the interaction between closure and temperature, whereas CIELAB parameters (lightness, chroma, hue) depended on closure-time and temperature-time interactions. At both storage temperatures, SC had a lower hue decrease and a lower chroma increase than C and SyC. The highest temperature prompted a more yellow and darker color of TRw. Thus, it allowed discrimination throughout the process. Considering the aging process, their aromatic intensity, fresh fruit, and yellow and green nuances decreased, while brown hue, color intensity, linalool, and oxidized character rose as their storage time was increased. At the end of their aging, TRw kept to 15 °C were not differenced by closure, and they were characterized by their fresh fruit, floral, and high aromatic intensity attributes. At 25 °C, SyC presented higher color intensity and herbaceous characters, while C and SC showed a more oxidized character. In conclusion, the interaction closure type-storage temperature is critical for organoleptic stability properties of bottled TRw during aging. Thus, screwcaps and low-temperature storage conditions can preserve the TRw varietal characteristics, increasing their shelf-life significantly.