{% for ProductCategory in Product.ProductCategories %} 
　{% if ProductCategory.Category.id == 1 %} 
　　{% for Category in ProductCategory.Category.path %} 
　　　{% for Category in Category.Children %}] 
　　　　{{ dump(Category) }} 
　　　{% endfor %}
　　{% endfor %}
　{% endif %}
{% endfor %}

{% for ProductCategory in Product.ProductCategories %} 
    {% if ProductCategory.Category.path[0].id == 1 %}
        {% for Category in ProductCategory.Category.path %} 
            {{ dump(Category) }} 
        {% endfor %}
    {% endif %}
{% endfor %}

{% for Product in Product.ProductCategories %}
　{% if Product.Category.path.0.id == 1 %}
　　{% if loop.last %}
　　　{% for Category in Product.Category.path %}
　　　　{% if loop.last %}
　　　　　{{ dump(Category.id) }}
　　　　{% endif %}
　　　{% endfor %}
　　{% endif %}
　{% endif %}
{% endfor %}

$id = $app['request']->get('id');
$Product = $app['eccube.repository.product']->get($id);

$ProductCategory = $Product['ProductCategories'];
$cnt1 = 1;
$cnt2 = 1;
$length1 = count($ProductCategory);
$length2 = array();
 foreach ($ProductCategory as $Product) {
  ++$cnt1;
  if ($Product['Category']['path'][0]['id'] == 790) {
   if ($cnt1 > $length1) {
    $length2 = count($Product['Category']['path']);
     foreach ($Product['Category']['path'] as $Category) {
      ++$cnt2; if ($cnt2 > $length2) {
      $CategoryId = $Category['id'];
     }
   }
  }
 }
}