Header title not center on Ios

Hi the title on Ios is shifted to the right because i have a left button. how can i fix it?

   <ion-header>
        <ion-navbar color="primary">
            <button ion-button menuToggle>
              <ion-icon name="menu"></ion-icon>
            </button>
            <ion-title>Feed</ion-title>
        </ion-navbar>
    </ion-header>