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Background and objectives: Rice contains an order of magnitude higher inorganic arsenic (iAs), a class 1 non‐threshold carcinogen, than other terrestrial crops. To reduce iAs in cooked rice, several methods have been proposed such as washing until clear, cooking with high water‐to‐rice ratio (W/R) then discarding excess water, or continuously percolating near‐boiling water. The traditional method practiced by 1.6 billion East Asians, washing and cooking with low W/R until dry, removes only a small percentage of iAs. A new approach was investigated to reduce iAs in cooked rice. Findings: Brief (10 min) soaking (W/R 10) at above gelatinization temperature (80°C) reduced iAs in rice by up to 48.4%. A soaking protocol was developed for public use that on average reduced 39.5 ± 6.6% (n = 12) iAs in non‐waxy white rice. Conclusions: Brief above‐gelatinization‐temperature soaking effectively reduces iAs in cooked white rice. Significance and novelty: Above‐gelatinization‐temperature soaking was applied for the first time to cut iAs in cooked rice; thereby chronic iAs exposure and cancer risk can be reduced for rice consumers. [ABSTRACT FROM AUTHOR]

Longan fruit is a popular subtropical fruit with a relatively short shelf life at room temperature mainly due to pericarp browning and fungal infection. This study aimed to investigate the infection of Phomopsis longanae Chi in longan fruit and its effects on the storability and shelf life of longan fruit. The relationship between the energy metabolism of harvested longan fruit and disease development and pericarp browning was elucidated. Results show that P. longanae-inoculation accelerated the deterioration of longan fruit and caused pericarp browning. It also led to the energy deficit in pericarp of longan fruit, which was reflected as lower contents of ATP and ADP, higher AMP content, and lower energy charge as compared to the control samples. Additionally, P. longanae-infection reduced the activities of H+-ATPase, Ca2+-ATPase, and Mg2+-ATPase in plasma, vacuolar, and mitochondrial membranes during the storage period. The results demonstrate that P. longanae-infection led to disease development and pericarp browning in harvested longan fruit, which were due to the infection-induced energy deficit and low ATPase activity that caused disorders of ion transport and distribution, and damaged the structure and function of vacuole, mitochondria, and eventually the whole cells of fruit tissues. [ABSTRACT FROM AUTHOR]

BACKGROUND Huanghua pear will lose its firmness quickly during postharvest storage at ambient temperature, and hence has limited storage and marketing potential. In this study, Huanghua pears treated with paper containing 0 (control) or 0.9 μL L−1 1-methylcyclopropene (1- MCP) for 12 h, and then stored at (25 ± 1) °C for 30 days, were investigated for the effect on fruit firmness, cell wall composition and activities of cell wall-degrading enzymes. RESULTS Huanghua pears without 1- MCP treatment softened rapidly during room-temperature storage and cell wall composition analyses showed an increase in water-soluble pectin ( WSP) and decreases in cell wall materials ( CWM) and cell wall components such as Na2CO3-soluble pectin ( NSP), cellulose and hemicellulose. In contrast, the 1- MCP-treated fruits maintained higher firmness than the control; also, the treatment prevented the formation of WSP and reduced the degradation of CWM and cell wall components including NSP, cellulose and hemicellulose. 1- MCP treatment also significantly lowered the activities of cell wall-degrading enzymes such as pectinesterase, polygalacturonase, β-galactosidase and cellulase during storage. CONCLUSION 1- MCP treatment can slow down the softening of Huanghua pears through reducing cell wall-degrading enzyme activities and hence maintain the integrity of the cell wall structure. © 2016 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• DNP accelerated P. longanae induced - longan pulp breakdown and softening process. • ATP suppressed P. longanae induced - longan pulp breakdown and softening process. • DNP promoted degradation of longan pulp cell wall but ATP showed the opposite effect. • DNP raised gene expression level and enzyme activity related to cell wall degradation. • ATP reduced gene expression level and enzyme activity related to cell wall degradation. Compared with P. longanae -infected longan, 2, 4-dinitrophenol (DNP) treatment for P. longanae -infected longan displayed the lower levels of pulp firmness, cell wall materials, ionic-soluble pectin, covalent-soluble pectin, hemicellulose, or cellulose, but the higher amount of water-soluble pectin, the higher activities of cell wall-degrading enzymes (CWDEs) (PG, β -Gal, PME, Cx, and XET), and the higher transcript levels of CWDEs-related genes (DlPG1 , DlPG2 , Dlβ-Gal1 , DlPME1 , DlPME2 , DlPME3 , DlCx1, and DlXET30). On the contrary, ATP treatment for P. longanae -infected longan exhibited opposite effects. The above results imply that DNP accelerated P. longanae -induced pulp softening and breakdown of fresh longan , which was because DNP up-regulated the transcript levels of CWDEs-related genes, enhanced the CWDEs activities, and accelerated the degradation of cell wall polysaccharides (CWP). However, ATP suppressed longan pulp softening and breakdown caused by P. longanae , because ATP down-regulated the transcript levels of CWDEs-related genes, lowered the CWDEs activities, and reduced the CWP degradation. [ABSTRACT FROM AUTHOR]

In order to reveal the complex relationship among the moisture content, the water activity and the temperature, and to provide technical data for preservation of dried 'Wuye' litchi (Litchi Chinensis Sonn. cv. Wuye), the static gravimetric method was used to determine moisture sorption isotherms of dried 'Wuye' litchi pulp at three temperatures (20, 30, and 40°C) over a range of water activities from 0.112 to 0.976 based on the adsorption theory. The experimental data of dried 'Wuye' litchi pulp were fitted by eight models (BET, Halsey, Henderson, Peleg, Smith, GAB, Modified Henderson, Oswin) available in the literature. The optimal model used to describe the sorption isotherms of dried 'Wuye' litchi pulp was determined by comparing the models' coefficient of determination (R2) and root mean square error. Thermodynamic properties such as net isosteric heat, enthalpy changes, entropy changes, and free energy that provide a deeper understanding of the properties of water and energy requirements associated with sorption process were determined from moisture adsorption isotherm data of dried 'Wuye' litchi pulp at different temperatures. The results showed that the moisture sorption isotherms of dried 'Wuye' litchi pulp exhibited type III sigmoid shape. At low and intermediate water activity, the equilibrium moisture content increased slowly with water activity (0.1-0.4), while at high water activity (>0.4) equilibrium moisture content increased rapidly with water activity. The equilibrium moisture content decreased with the increasing temperature at constant water activity. The Peleg model was found to be the best for describing the relationship between the moisture content, the water activity and temperature. The agreement between experiment and predicted values of this model was excellent (R2 ranging from 0.9950-0.9979，root mean square error ranging from 1.9431-2.7102). The thermodynamic properties of dried 'Wuye' litchi pulp showed that net isosteric heat of adsorption decreased with an increasing in moisture constant, and approached to zero at high moisture content. enthalpy changes had the same values as the net isosteric heat ranged from 0.95 to 186.98 kJ/mol. entropy changes values ranged from 1.11 to 587.24 J/(mol·K) at moisture levels ranging from 8%-50% for dried 'Wuye' litchi pulp. These values decreased as moisture content increased and did not show temperature dependence. Free energy ranged from 0.60 to 18.58 kJ/mol for dried 'Wuye' litchi pulp. Free energy became smaller as the moisture content and the temperature increased. The plot of the enthalpy versus entropy showed a linear relationship for dried 'Wuye' litchi pulp with R2 equal to 0.9999, which indicated the existence of compensation. The values of isokinetic temperature and harmonic mean temperature were 319.34 K and 302.93 K respectively. Therefore, the enthalpy-entropy compensation theory was suitable for water adsorption of dried 'Wuye' litchi pulp because isokinetic temperature was significantly different from the value of harmonic mean temperature. Since isokinetic temperature > harmonic mean temperature, the mechanism of the adsorption process of dried 'Wuye' litchi pulp was enthalpy driven. The results provide a theoretical basis for the processing and storage stability of dried 'Wuye' litchi pulp. [ABSTRACT FROM AUTHOR]