The invention pertains to the field of products in dry powder form obtained by lyophilization. The invention relates more particularly to a lyophilization method including a prior step of cryogeny under pressure of a matrix containing dissolved gas. It also relates to the powder obtained by this method and to the uses thereof in food processing, cosmetics, pharmacy, and human and animal health.

The invention pertains to the field of products in dry powder form obtained by lyophilization. The invention relates more particularly to a lyophilization method including a prior step of cryogeny under pressure of a matrix containing dissolved gas. It also relates to the powder obtained by this method and to the uses thereof in food processing, cosmetics, pharmacy, and human and animal health.

A method for preparing a vitamin D.sub.2-rich mushroom powder, including: slicing a mushroom to obtain mushroom slices, irradiating the mushroom slices with an ultraviolet light, drying the mushroom slices in nitrogen to obtain dried mushroom slices, and pulverizing the dried mushroom slices to obtain the vitamin D.sub.2-rich mushroom powder. The ultraviolet light irradiation is performed at an ambient temperature of 20-55° C. and an ambient relative humidity of 50-85%, and a moisture content of the mushroom slices is not less than 20%.

A method for preparing a vitamin D.sub.2-rich mushroom powder, including: slicing a mushroom to obtain mushroom slices, irradiating the mushroom slices with an ultraviolet light, drying the mushroom slices in nitrogen to obtain dried mushroom slices, and pulverizing the dried mushroom slices to obtain the vitamin D.sub.2-rich mushroom powder. The ultraviolet light irradiation is performed at an ambient temperature of 20-55° C. and an ambient relative humidity of 50-85%, and a moisture content of the mushroom slices is not less than 20%.

The present invention relates to a method for three-dimensional microwave air-jet drying of persimmon slices, comprising steps of grading and cleaning, slicing, microwave heating, steam de-astringency, hot-air reverse primary drying, negative-pressure intermittent secondary drying, cooling and packaging. In the present invention, high-temperature (60-70° C.) high-pressure annularly sprayed citric acid and 40% alcohol vapor (rotating at 360°) are adopted to remove astringency of persimmons, wherein high temperature causes more intense Brownian motion of liquid molecules; high pressure improves permeation and diffusion speed of de-astringency liquid in the persimmon slices; citric acid plays a membrane breaking role on persimmon cell membranes; and 40% alcohol vapor is allowed to rapidly diffuse into cells, so that tannin is polymerized into insoluble gel from a soluble state, thereby achieving a uniform and rapid de-astringency effect.

The present invention relates to a method for three-dimensional microwave air-jet drying of persimmon slices, comprising steps of grading and cleaning, slicing, microwave heating, steam de-astringency, hot-air reverse primary drying, negative-pressure intermittent secondary drying, cooling and packaging. In the present invention, high-temperature (60-70° C.) high-pressure annularly sprayed citric acid and 40% alcohol vapor (rotating at 360°) are adopted to remove astringency of persimmons, wherein high temperature causes more intense Brownian motion of liquid molecules; high pressure improves permeation and diffusion speed of de-astringency liquid in the persimmon slices; citric acid plays a membrane breaking role on persimmon cell membranes; and 40% alcohol vapor is allowed to rapidly diffuse into cells, so that tannin is polymerized into insoluble gel from a soluble state, thereby achieving a uniform and rapid de-astringency effect.

Described are dried cranberries with reduced sugar content, while retaining a desired sweetness and texture, and methods of making such dried cranberries. Dried cranberries include erythritol and a sweetener that interferes with erythritol crystallization.

Described are dried cranberries with reduced sugar content, while retaining a desired sweetness and texture, and methods of making such dried cranberries. Dried cranberries include erythritol and a sweetener that interferes with erythritol crystallization.

Technologies for controlling food dehydration in a low-oxygen environment include a control device and an enclosed drying chamber. The control device receives sensor data from environmental sensors disposed within the drying chamber. A concentration of oxygen within the drying chamber is determined based on the received sensor data. The control device controls a valve to selectively feed an amount of a combustible gas to a burner assembly disposed within the drying chamber. The burner assembly is ignited by the control device and a flame is produced. The flame depletes the concentration of oxygen within the drying chamber to an initial oxygen concentration level. The control device controls another valve to feed an amount of non-reactive gas into the drying chamber to flush the drying chamber and further deplete the concentration of oxygen within the drying chamber to a lower oxygen concentration level. Other embodiments are described and claimed.

Technologies for controlling food dehydration in a low-oxygen environment include a control device and an enclosed drying chamber. The control device receives sensor data from environmental sensors disposed within the drying chamber. A concentration of oxygen within the drying chamber is determined based on the received sensor data. The control device controls a valve to selectively feed an amount of a combustible gas to a burner assembly disposed within the drying chamber. The burner assembly is ignited by the control device and a flame is produced. The flame depletes the concentration of oxygen within the drying chamber to an initial oxygen concentration level. The control device controls another valve to feed an amount of non-reactive gas into the drying chamber to flush the drying chamber and further deplete the concentration of oxygen within the drying chamber to a lower oxygen concentration level. Other embodiments are described and claimed.