Black wood ear (Auricularia auricula-judae) is one of the major mushrooms produced and consumed in Taiwan. It is sold mainly in dried form. Before use, it is soaked in water for at least 15 minutes. Soaked or fresh wood ears are then cut up and added to other ingredients before being cooked and consumed as a vegetable. Nonetheless, TARI scientists strive to add value to black wood ear by developing processed products through research of its biochemical properties and health-care functions. The study revealed that black wood ear is rich in dietary fiber (polysaccharides) for digestion, but low in calories. Its insoluble fiber also contributes to a high water-holding capacity. Moreover, the Institute has developed efficient technologies for liquid extraction and powder making.

    For research on health-care functions of black wood ear, TARI has collaborated with Taiwan's China Medical University. Experimental results show that after feeding adult ovary-removed mice with liquid form of black wood ear extracts at 0.125 to 0.5 g/kg body weight for 16 weeks, the serum levels of high density lipoprotein cholesterol increased, and low density lipoprotein cholesterol and triglycerides decreased; the activities of the liver’s transaminases, GOT and GPT, reduced in serum; and bone density increased. These results indicate that black wood ear could be beneficial for protection against cardiovascular diseases, prevention of osteoporosis and alleviation of the female menopause symptom.

    The fruiting body of black wood ear usually soaks up 5-fold to 8-fold of water. And its dry extract powder can take up 100 to 120 times of water. Thus the extract powder is ideal as a thickener, emulsifier or extender in the food processing industry. The black wood ear’s extract powder can be used as a drink ingredient to make low-calorie but satiating beverages. For this, a recommended rate is 100 ml water to 1 g powder. After optimal rehydration, the black wood-ear extract powder can be used as an emulsifier and extender in making salad dressing to minimize the use of oils and fats such as soybean oil at 40-50%, or making juicy German sausages to reduce fat absorption by the intestine. The black wood ear’s extract powder can also replace portion of wheat flour to make low-calorie biscuits or noodles. With one third reductions of sugar and oil, the black wood-ear extract powder can replace 20-30% of wheat flour to make low-calorie biscuits. With an addition of black wood-ear extract powder, 3.0-7.5% of wheat flour can also be reduced to make low-calorie but satiating noodles. Beyond doubt, because of its unique biochemical properties, the black wood-ear extract powder can be employed in variegated food processing industries.