How long will unfermented prickly pear juice keep under airlock?

Hello everyone. I have a batch of prickly pears that have been juiced and stored about refrigerator temp, for about a week under airlock. My intentions were to start the batch but then my LHBS was closed day before and Christmas Day. So no yeast. Then got busy until now. If its going to spoil I don't want to waste the sugar and the yeast. I know watermelon spoils in about 24 hrs. Do you believe I am safe or should I scrap it before I start it?

Dose it with k-meta and you will be fine. Or freeze it. I had prickly pear juice in sealed mason jars for at least a month before I used it. My mead is fine.