In spite of the instability of certain vitamins, how can you guarantee their contents ? Purchase of best quality ingredients Manufacturing methods to avoid high temperatures Conditioning under environmental control and airtight, watertight and lighttight packaging Strict warehousing conditions (temperature, hygrometry conditions etc.) Overage proportional to the instability of the vitamins High frequency of production to minimise stocking period before utilisation None of the TWYDIL® products is released before having received the confirmation of its conformity to specification.