There were significant differences in sensory quality immediately after freezing, with overall assessment scores ranging
from 3.4 to 4.6 on a 5-point scale (Fig. 1). The significantly highest scores were gained by the products soaked in sodium metabisulphite solution and onion extract; the former product owed its high score to having the significantly (lightest colour (Figs. 1 and 2)), while the latter had very good flavour and aroma. The lowest sensory quality was found in the unsoaked product, whose colour and flavour were unacceptable. Sensory quality deteriorated after the 8-month storage period, mainly due to increased leakage of cell fluid, tissue darkening and distinct changes in flavour. The dominant hues in frozen A. bisporuswere honey and brown; (Fig. 2). The overall sensory quality assessment of frozen products ranged from 2.6 to 4.3 points. Unsoaked products and those soaked in organic acid solution failed to reach the minimum level of consumer acceptance (3.0 points) due to unacceptable colour (brown), flavour and, in the case of unsoaked mushrooms, aroma. The highest evaluation was achieved by the product soaked in sodium metabisulphite solution, largely on account of its colour and flavour. The product soaked in onion extract scored slightly lower (4.0 points). Its colour was significantly
less brown (by 1.0e2.0 points) than that of the unsoaked product or the product soaked in organic acid solution; the use of onion extract also brought about a marked improvement in flavour and aroma.