Table 1.

Technological and environmental factors related to the vitamin D2 improvement in edible mushrooms.

Technological and Environmental Factors	Comment	Reference
Type of effective irradiation	Increased effectiveness using UVB irradiation and sun exposure, rather than UVA and UVC irradiation.	[1,23,24,25,26,27,28,29,36]
Irradiation surface	The smaller the sample, the larger the exposure area and thus the greater the conversion of vitamin D2. Again, irradiating all sides of the cut allows a greater synthesis of vitamin D2 than simply exposing only one side.	[1,23,24,25]
Ideal reaction temperature	Between 25–29 °C. Data still insufficient and preliminary.	[1,23,24,25,36]
Exposure intensity	Higher efficacy for values between 1.14 and 1.36 W/m2 (values referring exclusively to irradiation with pulsed rays). There are no data correlating the conversion of ergosterols to ergocalciferol with the environmental UV index and/or factors such as latitude and time of day. Data still insufficient and preliminary.	[1,23,24,25]
Product type	Higher conversion efficiency in freeze-dried and heat-dried mushrooms than in fresh mushrooms. Data still insufficient and preliminary.	[1,23,25,36]
Sample storage	In fresh mushrooms, loss of about 23% vitamin D2 in mushrooms stored at 3–2 °C due to sample degradation, but no significant loss for storage at 4 °C. At room temperature, dried samples appear to have losses of about 50% after 18 months. Still insufficient and preliminary data.	[1,23,24,25]
Culinary transformations	Cooking induces a loss of vitamin D2, which differs depending on the type of cooking (greater in baking than in pan-frying). Data still insufficient and preliminary.	[1,23]