Possible Clues:

• Dietary necessity for one in ten
• Key dietary requirement, obtained from meat, eggs, milk and legumes
• Necessary food ingredient
• Substance in meat to ripen bananas
• Black beans are high in it
• Planned reception, missing church source of energy
• Essential dietary requirement
• Biomolecule made of chains of amino acid residue
• Essential part of diet is not ripe, unfortunately
• Tripe on toast is source of this