Effect of red thyme oil (Thymus vulgaris L.) vapours on fungal decay, quality parameters and shelf-life of oranges during cold storage.

This work has been aimed at studying the effect of red thyme oil (RTO, Thymus vulgaris L.) on the shelf-life and Penicillium decay of oranges during cold storage. RTO vapours significantly reduced (P ≤ 0.05) the percentage of infected wounds, the external growth area and the production of spores in inoculated orange fruit stored for 12 days at 7 °C in a polypropylene film selected for its appropriate permeability. Among the RTO compounds, p-cymene and thymol were the most abundant in packed boxes at the end of cold storage. The RTO vapours did not affect the main quality parameters of the oranges, or the taste and odour of the juice. The results have shown that an active packaging, using RTO vapours, could be employed, by the citrus industry, to extend the shelf-life of oranges for fresh market use and juice processing.

Volatile metabolites, quality and sensory parameters of "Ferrovia" sweet cherry cold stored in air or packed in high CO2 modified atmospheres.

Volatile organic compounds, quality and sensory attributes of sweet cherry cv "Ferrovia", cold packaged in Air or in different modified atmospheres (Low-O2 = 1% O2/0.03% CO2; High-CO2 = 16% O2/20% CO2; Mix = 1% O2/20% CO2), were monitored until 21 days of conservation. Results showed that sweet cherry cv "Ferrovia" is sensitive to CO2 accumulation (over 20%) in low oxygen (about 1%) modified atmosphere, as showed by the increase in respiration rate, biosynthesis of fermentative volatile metabolites, and sensory perception of off-odours. However, High-CO2 treatment seemed to preserve quality and sensory traits, presumably due to the high initial concentration of O2 (16%) that could limit the synthesis of ethyl esters and γ-butyrolactone, keeping the accumulation of off-flavours below their sensory perception threshold. Finally, PLSR analysis allowed to select 1-pentanol as putative marker of sensory alteration and hexanal and 2-hexenal as possible predictors of freshness for "Ferrovia" sweet cherries.

Changes in bacterial composition of zucchini flowers exposed to refrigeration temperatures.

Microbial spoilage is one of the main factors affecting the quality of fresh fruits and vegetables, leading to off-flavor, fermented aroma, and tissue decay. The knowledge of microbial growth kinetics is essential for estimating a correct risk assessment associated with consuming raw vegetables and better managing the development of spoilage microorganisms. This study shows, for the first time, that only a part of total microbial community, originally present on fresh harvested female zucchini flowers, was able to adapt itself to refrigerated conditions. Through the study of microbial growth kinetics it was possible to isolate forty-four strains belonging to twenty-two species of the genera Acinetobacter, Arthrobacter, Bacillus, Enterobacter, Erwinia, Klebsiella, Pantoea, Pseudoclavibacter, Pseudomonas, Serratia, Staphylococcus, and Weissella, suggesting Enterobacteriaceae as potentially responsible for pistil spoilage.