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The influence of different storage conditions on the storability of packaged shredded cabbage has been studied. The cabbage cultivar Field rocket was cut and packaged in glass jars and in polyethylene (PE) or polypropylene (PP) film. Several initial atmospheres were established within the packaged cut cabbage: 100 % N2, 5 % O2/95 % N2, 10 % O2/90 % N2, normal atmosphere (NA), 70 % O2/30 % N2 and 100 % O2. Samples were stored at two different temperatures of 0 and 10 °C for 7 days. Variation in CO2 and O2 concentrations was higher at 10 °C compared to 0 °C and the highest at the atmosphere consisting of 70 % O2/30 % N2. A decrease of O2 below 3–5 % and an increase of CO2 above 2–5 % in the packed product resulted in the appearance of anaerobic metabolism. An initial atmosphere consisting of 100 % O2, and a storage temperature of 0 °C resulted in delayed anaerobic metabolism compared to other atmospheric conditions and storage temperature of 10 °C. Rinsing of fresh cut cabbage also resulted in lower accumulation of acetaldehyde and ethanol. A higher variation in CO2 and O2 concentrations, and consequent accumulation of anaerobic metabolites had a negative influence on the sensorial properties of the cut cabbage. The higher permeability of PE film compared to PP and glass enabled faster exchange of CO2 and O2, which resulted in lower accumulation of anaerobic metabolites. However, a higher O2 concentration had a negative influence on the colour of fresh-cut cabbage. The best results were achieved by packing the fresh-cut cabbage in PE film with an initial atmosphere of 100 % O2 and stored at 0 °C. [ABSTRACT FROM AUTHOR]

The staling of ground roasted coffee blend was studied over one year of storage. Solid phase microextraction-gas chromatography-mass spectrometry analysis was carried out to identify and semi-quantify 40 volatile compounds. We focused on volatile compounds related to the ageing of coffee: methanethiol, propanal, 2-methylfuran, 2-butanone, 2,3-butanedione, 2-furfurylthiol and hexanal. Changes in sensory properties of coffee beverage prepared from the ground roasted coffee samples during storage in laminate packages (PET/ aluminium foil/PE) under air atmosphere, under nitrogen or in punctured packages were determined. Samples were stored at (23±2) °C and (40±10) % relative humidity. The reference coffee was packed similarly in laminate packages under nitrogen and stored at (–20±1) °C. Applying a statistical assessment of the results, we found the loss of most volatile compounds from all stored coffee samples, including even those stored under freezing conditions. The ratios of 2-methylfuran/2-butanone and methanethiol/hexanal proved useful indicators of staling. Our new proposed aroma index, the ratio of 2-furfurylthiol/ hexanal, proved to be the most effective, giving high correlation coefficients (R³0.80) with aroma freshness for coffee brews prepared from the ground roasted coffee stored under different conditions at room temperature. [ABSTRACT FROM AUTHOR]