未来的西瓜生物燃料

Forget chip fat， sugar cane or rapeseed oil—the future source of biofuel could be watermelons.

Scientists have discovered that the fruit is a great source of sugar that can be readily distilled into alcohol to power cars and farm machinery.

Retailers reject 360，000 tons of “substandard” fruit annually in America alone， and they could be used as an economical way to make fuel.

The fruit from U.S. growers could produce nearly two million gallons （nine million litres） of biofuel per year.

In the study， researchers at the United States Department of Agriculture set out to determine the biofuel potential of juice from “cull” watermelons—those not sold due to cosmetic imperfections， and currently ploughed back into the field.

About a fifth of each annual watermelon crop is left in the field because of surface blemishes or because they are misshapen.

Dr. Wayne Fish， who led the team， found that 50 per cent of the fruit was fermentable into ethanol which could provide valuable fuel.

“We’ve shown that the juice of these melons is a source of readily fermentable sugars， representing a heretofore untapped feedstock for ethanol biofuel production，” he said.

The study， published in the journal Biotechnology for Biofuels， discovered that watermelons could produce around 20 gallons of fuel per acre from fruit that otherwise would go to waste.

Production of biofuels has been targeted by western governments as a way to bolster renewable energy targets.

忘掉廉价的肥肉、甘蔗或菜籽油吧，西瓜有望在未来成为生物燃料的来源。

科学家们发现，水果中含有大量糖分，可直接用于提炼酒精，从而为汽车和农用机械提供动力。

每年仅美国的零售商遗弃的“不合格”水果就达36万吨，而这些水果可通过一种十分经济的方法来制造燃料。

美国水果种植商每年扔掉的水果可生产出近200万加仑（900万公升）的生物燃料。

在这项研究中，美国农业部的研究人员开始测定这些“被淘汰的”西瓜的汁液究竟具有多大的潜在利用价值。被淘汰的西瓜指的是那些由于外表瑕疵未上市，又被淘汰回地里的西瓜。

每年约有五分之一的西瓜因外表瑕疵或形状不规则而被丢弃在田地里。

研究小组负责人韦恩·费什博士发现，50%的西瓜汁可发酵产生乙醇这种宝贵的燃料。

他说：“我们已经发现西瓜汁中含有易发酵糖，这种原料在乙醇生物燃料的生产中尚未被利用过。”

这项在《生物燃料的生物科技》期刊上发表的研究发现，每英亩的西瓜能产生出约20加仑的燃料。如果不加以利用，这些水果会白白浪费掉。

西方国家已经瞄准生物燃料的生产，以此促进可再生能源的发展。