Preservation Treatments Affect Sensory Quality of Oyster Mushroom

Oyster mushrooms are nutritious, flavorful, and are known to have some medicinal properties. Their production requires low capital investment and minimal expertise and thus they can potentially be a source of nutrition and income in resource limited communities. However, one limiting factor is that oyster mushrooms spoil easily and thus require preservation to extend their shelf life. This study investigated the effect two drying treatments (solar and oven), three blanching treatments (no blanching, water and steam), and four chemical pretreatments (no chemical, lemon juice, vinegar and potassium bisulfite) on oyster mushroom sensory quality. The pretreated dehydrated oyster mushrooms were assessed by a trained panel who rated the mushroom’s flavor, texture and appearance attributes on a 174 mm scale. Mean ratings were calculated and analysis of variance was done using Statistical Analysis System (SAS Inst. 1988) with the use of least significant figures to separate means. Among the un-blanched samples, those that did not receive any chemical pretreatment and those that were pretreated with lemon juice before drying were found to have better appearance, flavor and were more generally acceptable when compared to those with the vinegar and potassium bisulfite treatments.  However, when a blanching treatment was included, samples that were treated with potassium bisulfite had superior quality when compared to those treated with lemon juice, vinegar and the control. Solar drying resulted in more browning when compared to oven drying. Water blanching resulted in a more fibrous texture when compared to steam blanching.

Keywords: oyster mushroom, sensory, preservation, chemical pretreatments, blanching