As a rule, if a person begins eating a fruit or drinking a beverage in his home, and he leaves before reciting "Boreh Nefashot," he must recite a new Beracha if he wishes to continue eating or drinking outside.
An important exception to this rule, however, is the case of "Holecheh Derachim," where a person eats as he travels. A person who eats or drinks in a car, bus or train does not have to recite a new Beracha when he continues eating or drinking after disembarking, even though he is no longer in the same place where he had initially recited the Beracha. By the same token, if a person begins eating or drinking at home, but it is clear that he is on his way out, then he falls under the category of "Holecheh Derachim" and does not have to recite a new Beracha when he resumes eating out of the house. For example, a person begins eating a fruit and sipping coffee standing up, while he’s putting on his jacket and putting his things together to go to work. Since it is clear he recited the initial Beracha with the intention of bringing the fruit and coffee outside, he does not recite a new Beracha outside. If, however, he sat down to drink coffee at the table, and then realized he needed to leave, then he would, indeed, have to recite a new Beracha when he resumes eating or drinking outside. Since he established himself as eating at home, bringing the food outside would constitute "Shinui Makom" and require a new Beracha.
This is the ruling of several Halachic authorities, including Hacham Bension Abba Shaul (Israel, 1923-1998) and Hacham Ovadia Yosef, as discussed in Yalkut Yosef (p. 94; listen to audio recording for precise citation).
Another example of this Halacha occurs frequently in synagogues that serve breakfast or refreshments after prayers in the morning. If a person sits down at the table with the other congregants to have coffee and fruit, and then he leaves, he would have to recite new Berachot over the fruit and coffee outside. Often, however, a person knows he only has a minute or two before he needs to leave, and so he takes a coffee and some food without establishing his place at the table. In such a case, since it is clear he intends to take the food and beverage with him, he does not recite new Berachot when he goes outside.
Another example is somebody who stops off at a 7-11 on his way to work to buy a cup of coffee. If he recites the Beracha in the store and takes a sip, he clearly does not have to recite a new Beracha when he drinks outside the store, or when he gets into his car. A person who begins drinking in a 7-11 is no different from someone who begins drinking while in transit, and thus does not recite a new Beracha when he gets into his car. The same applies if a person buys a coffee, recites a Beracha, and brings it with him to the train and then into the office. Since he recited the Beracha when he was in transit, and clearly intended to drink the coffee as he traveled, he does not recite a new Beracha when he moves from one location to another.
There is some debate among the Halachic authorities concerning the case of one who recited a Beracha and began drinking in his car when it was in "park," before he started driving. According to some authorities, since the person clearly intends to immediately begin driving, this case, too, falls under the category of "Holecheh Derachim," and he does not recite a new Beracha when he continues drinking while driving. Others, however, claim that in such a case the person establishes the car as his location, and he must therefore recite a new Beracha when he continues eating after leaving the car. Due to this uncertainty, a person in this case should not recite a new Beracha. However, it is best to avoid this situation and not begin eating in a parked car unless one intends to finish the food or beverage before exiting the car. One should instead recite the Beracha and begin eating or drinking only after he begins driving, when standing at a red light (as one should preferably not recite a Beracha while driving).
Summary: If a person recites a Beracha over a fruit or beverage when it is clear that he is preparing to leave, he does not recite a new Beracha when he continues eating or drinking after he leaves. Examples include somebody who begins drinking coffee in his house as he is putting on his coat and getting ready to leave, or somebody who begins drinking coffee in the 7-11 and then makes his way to his car or the train. As long as a person is clearly "in transit" when he recites the Beracha and begins drinking, he does not recite a new Beracha when he changes locations.
