Trim date format PrimeNG calendar - remove timestamp, angular reactive forms

I have the following pushed into my reactive forms obj 2016-01-01T00:00:00.000Z but I want the following 2016-01-01.

Does anyone know of a built in function to achieve the above. I've searched the docs here but no luck. A .trim would of course work fine in a callback, but I'm wondering if anyone has done this before and knows a built in functionality.

Thanks.

UPDATE

To help others - this is how I solved it with the help of the answer below using primeng calender, reactive forms in angular. Using (onSelect) callback specific to primeNg Calendar

import { DatePipe } from '@angular/common';

<p-calendar
    #purchaseDateRef
    (onSelect)="handleSelect(purchaseDateRef)">
</p-calendar>


constructor(
    private datePipe: DatePipe
) {}

handleSelect(event: any) {
  // manipulate date object with help of DatePipe and setValue
  this.form.get('registrationFields.appliance.purchaseDate')
     .setValue(this.datePipe.transform(event.value, 'y.MM.dd')
  );
}