[Detection of adulterations of fruit juices with nature identical acids with isotope ratio measurements]

acide ascorbique acide citrique acide malique acido ascorbico acido citrico acido malico adulteration analytical methods apple juice ascorbic acid chemical structure citric acid control de calidad fruit juices jugo de frutas jus de fruits jus de pomme malic acid structure chimique technique analytique technique des traceurs tracer techniques zumo de manzana