Most countries prohibit "unprocessed" meat products due to the danger of disease, and NZ is no exception. The US regards most smoked meats as "unprocessed", not sure how NZ would treat beef jerky. They are likely to err on the side of caution and confiscate your jerky. I wouldn't try smuggling it in as they often use dogs and I imagine a dog would make a beeline for the beef jerky. This would net you a hefty fine along with a thorough search of the rest of your luggage and person (in case the jerky was cover for narcotics).