var arrayObj = [{name:"bull", text: "sour"},
    { name: "tom", text: "tasty" },
    { name: "tom", text: "tasty" }
]
var index = arrayObj.findIndex(x => x.name=="bob"); 
// here you can check specific property for an object whether it exist in your array or not

index === -1 ? arrayObj.push({your_object}) : console.log("object already exists")