This study aimed to analyze the characteristics of extracted protein enzymes from over-matured, used-up fruits such as kiwifruit, grape, apple, and pear; and to apply these extracts as a tenderizer for beef sausage. Kiwifruit showed the highest protease activity (921.08 unit), and grape showed medium activity (225.86 unit), whereas pear and apple showed lower values (97.75 and 78.29 unit, respectively). After 2 weeks, the protease activity of all over-matured fruits increased by approximately 16.9%, and the maximum protease activity appeared in the temperature range of $50-60^{circ}C$, depending on the fruit extract. Failure stress was measured after adding the over-matured fruit extracts to the beef, and various tenderizers were manufactured using an optimizing technique according to a mixing ratio by each protease activity. The more kiwifruit content was added, the more the beef texture became soft. The optimum mixing ratio was categorized according to age groups such as elderly, middle, and young people.