1. Just thinking of all that yummy food makes my mouth water.
光想到那些可口的食物我就会口水直流。
这些都是用来形容“美味”的词：tasty, yummy, scrumptious, mouth-watering, toothsome, luscious, delectable, savory, marvelous. (Note: tasty is mild and common; yummy, scrumptious, mouth-watering, and toothsome are all colloquial; luscious, delectable and savory are more educated; marvelous is educated speech)
2. The fish hotpot here is not authentic Sichuan cuisine.
这儿的水煮鱼不是正宗的四川菜。
Although it tastes all right, it's slightly different from the authentic or typical flavor. 注意这里用来形容“正宗”的词，可以用 authentic 或者 typical。
3. The bread tastes like cardboard.
这种面包味同嚼蜡。
“纸箱馅包子buns with cardboard stuffing”的假新闻大家还有印象吧，taste like cardboard可是英语里一个常用的表达，用来形容不好吃的食物。
4. Take those gross noodles away!
把那些恶心的面条端开！
For food that tastes not so good, we have other expressions like "an unsavory meal" (一顿难吃的饭) and "disgusting, gross, and nauseating food". (注意: "unsavory" (难吃的) is very polite English; "disgusting" (令人厌恶的) is harsh but commonly-used; "gross" is very popular teen speech; "nauseating" (令人作呕的) is a very strong word.)
5. The food in our dining hall is the pits!
我们食堂的东西难吃极了。
Here, "pits" is an adjective very popular with teens and 20-somethings, meaning "the worst". For example, "That apartment the company gave me to live in is the pits, no bathroom, a tiny kitchen, and no air conditioner." (公司提供的公寓糟糕透了，没有洗手间，厨房只有巴掌大，还没有空调。)
