Actinidin is known to affect the taste, allergenic properties and characteristics for food processing of the kiwifruit.  The actinidin concentration and the protease activity in the fruit juice were determined in kiwifruit of 13 cultivars obtained in Japan (six Actinidia deliciosa, five A. chinensis and two A. arguta cultivars)  by quantitative sodium dodecyl sulfate-polyacrylamide gel electrophoresis and spectrophotometric assay using L-pyroglutamyl-L-phenylalanyl-L-leucine p-nitroanilide as a substrate.    In Abbott, Koryoku, Kuimi and Sinzan, both actinidin concentration and protease activity in the juice were significantly higher than those of Hayward, the most common cultivar of kiwifruit.  In contrast to these cultivars, protease activities in Rainbow red, Hort16A and Kosui fruit juice were less than 7% of that of Hayward.
   In Rainbow red, Hort16A and Kosui, little or no proteolytic effect on milk or pork myofibrillar proteins was observed. Addition of sliced or pureed flesh of Rainbow red, Hort16A or Kosui to the gelatin jelly did not prevent the jelly from setting, whereas gelatin was thoroughly hydrolyzed by the kiwifruit juice in most of the cultivars  Protease activity in Kosui puree, when added to gelatin jelly at 50%, caused only 4-10% decrease in gel strength.  These results suggest that the raw fresh of Kosui kiwifruit can be satisfactorily used in gelatin-based foods as an ingredient.
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For details, see the following papers.

Adv. Food Nutr. Res., 52, 293-324 (Nishiyama, 2007)

(Text in Japanese.  Abstract, figures, and tables in English.)
  J. Home Econ. Jpn., 51, 621-626 (Nishiyama, 2000)
  J. Japan. Soc. Food Sci. Technol., 49, 401-408 (Nishiyama and Oota, 2002)
  J. Japan. Soc. Food Sci. Technol., 51, 491-494 (Yamanaka et al., 2004)
  J. Japan. Soc. Hort. Sci., 73, 157-162 (Nishiyama et al., 2004).