Scientists are reporting development of a new approach for producing large quantities of human-derived（导出的，衍生的） gelatin（明胶，动物胶） that could become a substitute for some of the 300,000 tons of animal-based gelatin produced annually for gelatin-type desserts, marshmallows（棉花糖） , candy and innumerable other products. Their study appears in ACS's Journal of Agriculture and Food Chemistry. Jinchun Chen and colleagues explain that animal-based gelatin, which is made most often from the bones and skin of cows and pigs, may carry a risk of infectious diseases such as "Mad Cow" disease and could provoke（驱使，激怒） immune system responses in some people. Animal-based gelatin has other draw-backs, with variability from batch to batch, for instance, creating difficulties for manufacturers. Scientists thus have sought alternatives, including development of a human-recombinant gelatin for potential use in drug capsules（胶囊） and other medical applications.

To get around these difficulties, the scientists developed and demonstrated a method where human gelatin genes are inserted into a strain of yeast（酵母） , which can produce gelatin with controllable features. The researchers are still testing the human-yeast gelatin to see how well it compares to other gelatins in terms of its viscosity（粘性，粘度） and other attributes. Chen and colleagues suggest that their method could be scaled up to produce large amounts of gelatin for commercial use.