There\'s a new frontier in 3Dprinting that\'s beginning to come into focus: food. Recentdevelopment has made possible machines that print, cook, and servefoods on a mass scale. And the industry isn\'t stoppingthere.

Foodproduction

With a 3D printer, a cookcan print complicated chocolate sculptures and beautiful pieces fordecoration on a wedding cake. Not everybody can do that -- it takesyears of experience, but a printer makes it easy. A restaurant inSpain uses a Foodini to \"re-create forms and pieces\" of food thatare \"exactly the same,” freeing cooks to complete other tasks. Inanother restaurant, all of the dishes and desserts it serves are3D-printed, rather than farm to table.

Sustainability(可持续性)

The global population is expected to growto 9.6 billion by 2050, and some analysts estimate that foodproduction will need to be raised by 50 percent to maintain currentlevels. Sustainability is becoming a necessity. 3D food printingcould probably contribute to the solution. Some experts believeprinters could use hydrocolloids(水解胶体) from plentiful renewables like algae(藻类) and grass to replace the familiaringredients(烹饪原料). 3D printing can reduce fuel use and emissions. Grocerystores of the future might stock \"food\" that lasts years on end,freeing up shelf space and reducing transportation and storagerequirements

Nutrition

Future 3D food printerscould make processed food healthier. Hod Lipson, a professor atColumbia University, said, \"Food printing could allow consumer toprint food with customized nutritional content, like vitamins. Soinstead of eating a piece of yesterday\'s bread from thesupermarket, you’d eat something baked just for you ondemand.\"

Challenges

Despite recent advancements in 3D foodprinting，the industry has many challenges to overcome. Currently,most ingredients must be changed to a paste(糊状物) before a printer can use them, and the printing processis quite time-consuming because ingredients interact with eachother in very complex ways. On top of that, most of the 3D foodprinters now are restricted to dry ingredients，because meat and milk products may easily go bad. Someexperts are skeptical about food printers, believing they arebetter suited for fast food restaurants than homes and high-endrestaurants.

46．What benefit does 3D printing bring to foodproduction？

A. It helps cooks to createnew dishes.B. It saves time and effort in cooking.

C. It improves the cookingconditions.D. It contributes to restaurant decorations.

47．What can we learn about 3D food printing from Paragraph3？

A. It solves food shortageseasily.B. It quickens the transportation of food.

C. It needs no space for thestorage of food. D. It uses renewablematerials as sources of food.

48．According to Paragraph 4，3D-printed food ____ .

A. is more available toconsumersB. can meet individual nutritional needs

C. is more tasty than foodin supermarketsD. can keep all the nutrition in raw materials

49．What is the main factor that prevents 3D food printing fromspreading widely?

A. The printing process iscomplicated.B. 3D food printers are too expensive.

C. Food materials have to bedry.D. Some experts doubt 3D food printing

50．What could be the best title of thepassage?

A. 3D Food Printing:Delicious New Technology

B. A New Way to Improve 3DFood Printing

C. The Challenges for 3DFood Production

D. 3D Food Printing: FromFarm to Table

BDBCA

46. B 推理判断。根据第二段but a printer makes it easy.判断。

47. D 细节理解。根据第三段Some experts believe printers could usehydrocolloids(水解胶体) from plentiful renewables like algae(藻类) and grass to replace the familiaringredients(烹饪原料).确定。

48. B 细节理解。 根据第四段Food printing could allow consumer to print food withcustomized nutritional content, like vitamins.及后一句中的on demand确定。

49. C 推理判断。根据第五段On top of that, most of the 3D food printers now arerestricted to dry ingredients，because meat and milk products may easily gobad.判断。

50. A 标题主题。3D打印食物还是一件新鲜事儿，远未成熟。C项是最后一个自然段的中心思想。D项可以根据第二段最后一句话排除。