根据美国《统一商法典》第 2-314 条至第 2-316 条规定，卖方在产品的销售中应承担一项默示担保义务，即保证他所出售的货物必须具有适合商销的品质，这里涉及到英美法买卖交易中常用的两个概念，一个是商销性（ Merchantability ），也称适销性，简言之就是商品适合销售，指出售的商品应属于所述货物的通常品种，适合于该商品的一般用途。

另一个概念是默示担保（implied warranty），指在卖方的确认中暗示的，而非用专门术语表达的对质量的担保，这种担保是事实默示的担保，而不是法律默示的担保。例如，根据《美国统一商法典》第2-314条的规定，如果卖方系从事某种货物交易的商人，他就该对这种货物之商销性进行担保，也即为买卖合同中的默示担保。

（According to UCC § 2-314, a warranty that the goods shall be merchantable is implied in a contract for their sale if the seller is a merchant with respect to goods of that kind.）

上世纪80年代初期，美国的阿拉巴马州就发生了涉及这两个概念的一个经典判例，即Morrison’s Cafeteria of Montgomery. Inc. v. Inez Haddox. Etc. Supreme Court of Alabama 431 SO. 2D 975案:

案件事实facts

One afternoon in May 1980, Mrs. Haddox and her three-year-old son Rodney went to Morrison's Cafeteria. Rodney wanted some fish. Mrs. Haddox asked for and received a portion of the fish， then she pulled it apart with her knife and fork into very small pieces. Rodney apparently became choked on the first bit of fish. When Rodney was taken to the hospital, it was discovered that a fishbone approximately one centimeter in length was lodged in his tonsil. The bone was removed after Rodney stayed in the hospital overnight. He suffered no permanent physical injury as a result of the incident. According to  Mrs. Haddox, the manager and other personnel at Morrison's were extremely rude to her during the course of Rodney's difficulty. She could not persuade anyone to take her to the hospital and was told at the checkout counter that she must pay her bill before she left.

一位妈妈带着三岁的儿子去一家快餐店用餐，母亲为孩子叫了一个鱼柳饭，鱼柳拿到手的时候，妈妈怕孩子被鱼刺卡到，把鱼肉分成一口一口的大小，喂给孩子，可是孩子还是被卡到了，后来在母亲为孩子解决鱼刺卡在嗓子里的过程中，饭店很不配合，几经周折之后，母亲没有得到饭店应该给的补偿，于是向法院提起了诉讼。但是被告一方拒绝向母亲一方进行赔偿，认为自己提供的鱼柳饭并没有什么质量上的瑕疵，于是二者对簿公堂。

该案件经过了两审，一审巡回法院判决母亲Haddox太太胜诉，判给了母亲和孩子大概五六千元的赔偿。被告不服，提起了上诉，也就因此有了我们现在看到的二审的判决，最高法院推翻了一审的判决，支持了被告的抗辩理由，发回重审。以下是法官的经典判词:

Goods to be merchantable must be at such as (c) Are fit for the ordinary purposes for which such goods are used.

商品的商销性是指商品必须符合该类商品能够满足同类产品使用目的的默示担保。

注释：

《美国统一商法典》第2-316条第二款：

For goods to be merchantable, they must be at least such as:

(a) pass without objection in the trade under the contract description; and

(b) in the case of fungible goods, are of fair average quality within the description; and

(c) are fit for the ordinary purposes for which such goods are used; and

(d) run, within the variations permitted by the agreement, of an even kind, quality within each unit and among all units involved; and

(e) are adequately contained, packaged and labeled as the agreement may require; and

(f) conform to the promise or affirmations of fact made on the container or label if any

货物至少应达到下列标准才具有商销性：

ａ．根据合同所提供的说明，货物应在本行业内可以不受异议地通过；并且

ｂ．货物如果为种类物，应在说明的范围内具有平均良好品质；并且

ｃ．货物应适用于该种货物的一般使用目的；并且

ｄ．货物每个单位内部或全体单位之间的种类、质量或数量应均匀，差异不超出协议许可的范围；并且

ｅ．货物应按协议的要求装入适当的容器，进行适当的包装和附以适当的标签；并且

ｆ．如果容器上或标签上附有保证或说明，货物应与此种保证或说明相符。

The undesirability of the foreign substance test lies in the artificial application at the initial stage of processing the food without consideration of the expectations of the consumer in the final product served.

人工添加标准不考虑消费者对食物的预期，而是考虑食物加工过程中是否存在人工添加的成分。

Surely it is within the expectation of the consumer to find a bone in a T-bone steak; but just as certainly it is reasonable for a consumer not to expect to find a bone in a package of hamburger meat. It is entirely possible that a natural substance found in processed food may be more indigestible and cause more injury than many "foreign" substances.

当然，如果在牛排当中发现T型的骨头，是合乎消费者预期的，相反，在汉堡包的肉片当中发现骨头则违反消费者的预期。在经过加工的食物中有时天然成分可能比添加成分更难消化、更易对人类造成损害。