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In this study, the effects of cold storage (5±0.5°C and relative humidity of 90±1%) on the quality of fresh papaya slices packed in a passive atmosphere with a semi-permeable film were evaluated. Physico-chemical traits such as total soluble solids, reducing sugar, pH increased during storage as well as the polyphenols, carotenoid content and antioxidant activity that reaching the highest values at end of trials. Changes in colorimetric parameters resulted in a significant decrease after 4 days of hue angle values, which then remained constant. The cutting process enhanced the antioxidant enzymes activity such as superoxide dismutase, catalase and ascorbate peroxidase. The analysis of the main components showed physical-chemical, qualitative, and enzymatic changes in papaya samples during cold storage, showing a shift from negative to positive values along the PC1 and indicating a qualitative decay of sliced papaya. [ABSTRACT FROM AUTHOR]

In a previous paper the effect of chemical pre-treatment on quality attributes of 'Annurca' apple slabs dried at different temperatures was investigated. Herein, we evaluated the effect of the same pre-treatment on the quality attributes of the same dried 'Annurca' apple samples rehydrated at two temperatures. Specifically, slabs were initially pretreated in a dipping solution containing trehalose, sodium chloride, sucrose. Then, they were dried by using a convective dryer at 50°, 55°, 60°, and 65°C, and rehydrated at 30° and 70°C by immersion in water. The combination of pre-treatment, drying at 65°C and rehydration temperature of 30°C enabled to obtain the best preservation of rehydration indices (i.e, water absorption capacity), structure and colour properties. On the contrary, the highest antioxidant activity (EC50) in treated samples was found at the lowest drying temperatures (50° and 55°C) among those investigated and rehydration temperature of 30°C. The PCA provided different behaviours among untreated and treated dried apples when rehydrated at 30° and 70°C, demonstrating that this pre-treatment combined with drying/rehydration temperatures influenced the quality attributes of rehydrated samples. [ABSTRACT FROM AUTHOR]

The influence of an alternative chemical pretreatment on dehydration and rehydration of an Italian ecotype pumpkin was investigated. The pretreatment consisted of soaking the slices in a diluted solution of trehalose, sucrose and NaCl. Hot air-drying was performed in a convective dryer at temperatures of 55, 60, 65 and 70°C. Samples treated prior to drying showed a shorter (about 1/4) drying time, less volume shrinkage and colour changes, but showed higher rehydration capacity compared to untreated ones, especially in the range 55-65°C. Moreover, the pretreatment was effective in retention of total phenolic content and antioxidant activity. The Midilli model was the most appropriate for describing drying behaviour, while the Weibull model for rehydration. [ABSTRACT FROM AUTHOR]

The effect of modified atmosphere packaging (MAP) with and without a moisture adsorbent, on the quality of squid (Sepia officinalis) during chilled storage, was evaluated. Chemical and microbiological tests were carried out to measure the amount of spoilage and the resulting loss of fish freshness during 12 days of storage at 3°C. After 11 days, trimethylamine nitrogen (TMA-N) increased from 0.4 mg/100 g in fresh samples to 24 mg/100 g in MAP with adsorbent and 35 mg/100 g in the other samples. Total volatile basic nitrogen (TVB-N) increased from 18 mg/100 g in fresh samples to 112 mg/100 g in MAP with adsorbent and 158 mg/100 g in control samples. Counts of aerobic psychrotrophic microorganisms and presumptive Pseudomonads were more than 10 times lower in both MAP treatments compared to the control, in which counts exceeded 106 cfu/g on day 9, and 107 cfu/g on day 12. [ABSTRACT FROM AUTHOR]