/**
 * Before save type related data
 *
 * @param MagentoCatalogModelProduct $product
 * @return $this
 */
public function beforeSave($product)
{
    parent::beforeSave($product);

    $options[] = array(
        "sort_order"    => 1,
        "title"         => "Select Date",
        "type"          => "date",
        "is_require"    => 1,
        "price_type"    => "fixed"
    );
    $product->unsetOptions();
    $product->setHasOptions(1);
    $product->setCanSaveCustomOptions(true);
    $product->getResource()->save($product);
    $product->setOptions(array());
    foreach ($options as $arrayOption) {
        $option = $this->_objectManager->create('MagentoCatalogModelProductOption')
            ->setProductId($product->getId())
            ->setStoreId($product->getStoreId())
            ->addData($arrayOption);
        $option->save();
        $options[] = $option;
        $product->addOption($option);
    }

    return $this;
}