Effect of different drying methods on water loss rate and nutritional value of Broussonetia papyrifera

Broussonetia papyrifera is a woody plant species in the family Moraceae, and due to its high protein content is widely used in the feed industry in southwest China. To examine the differences in drying methods for hay production, we investigated water loss rates and nutritional value of B. papyrifera as an example to optimize the available technologies to achieve preservation of nutrients for substituting succulent feeds or concentrates. In the article, we present the results of cluster analysis of 23 drying methods, sub-divided into three groups: quick drying, medium-speed drying, and slow drying. Water loss rate could be improved in small stacks, and the fastest way of drying was squashing and cutting the plant material to a length of 10 cm. Based on calculated feeding values of a factor analysis, we found that the optimal method was cutting of plant material to 10 cm pieces and applying a 2% K2CO3 treatment, achieving a score of 0.514. When the stem structure was destroyed by applying a treatment of spraying K2CO3, the cutting method further decreased the superficial area of the vascular bundle, which enhanced the feeding value.