Problem with custom post & shortcode

Hello,
I try to change :
<?php echo do_shortcode( '[ingredients]' ) ?>

This is a multiple values list, but I don’t manage to change it.

The shortcode is here :

// [ingredients] short code
function show_ingredients($atts, $content = null) {

	extract(shortcode_atts(array(
									'title' => ''
								), $atts));

	global $post;		

	$ingredients = get_post_meta($post->ID, 'RECIPE_META_ingredients');	

	$ingredients_count = count($ingredients[0]);

	if(empty($title))
	{
		$ingredients_html = '<h3>'.__('Ingredients','woothemes').'</h3>';
	}else{
		$ingredients_html = '<h3>'.$title.'</h3>';
	}

	if( $ingredients_count >= 1 && (!empty($ingredients[0][0])) )
	{
		$i = 0;
		$ingredients_html .= '<ul class="ingre">';

		while($i < $ingredients_count)
		{
			$ingredients_html .= '<li> ';
			$ingredients_html .= $ingredients[0][$i];
			$ingredients_html .= '</li>';
			$i++;
		}

		$ingredients_html .= '</ul>';
	}
	else
	{
		$ingredients_html .= '<p>';
		$ingredients_html .= __('No Ingredients Found ! ','woothemes');
		$ingredients_html .= '</p>';
	}

	return $ingredients_html;

}
add_shortcode('ingredients', 'show_ingredients');

I tried to change almost anything but I don’t manage to succeed.

For example the :

<ul>
<?php
$values = get_editable_post_meta( get_the_ID(), 'my_key' );
foreach ( $values as $value )
    echo '<li>' . $value . '</li>';
?>
</ul>

make this error :
Warning: scalar expected. array given in /homepages/3/d440635061/htdocs/recette-vegan/wp-content/plugins/front-end-editor/php/fields/base.php on line 78
The only thing I can modify is the word Array…

Can someone help me ?
Thank you

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