This chapter, which is based on selected scientific reports, focuses on the multivariate assessment of the multielemental composition and stable isotope ratio differentiation of fruits and fruit juices. Food authentication enables the assessment of food safety. Adequately selected analytical methods or techniques integrated with computational tools are useful in the evaluation of the adulteration/mislabelling of fruit and its products. The thoughtful choice of combined methods for fruit investigation allows evaluation of its nutritive value. Owing to this approach, it has been possible to differentiate conventionally grown fruits from those that are organically cultivated. Moreover, the combination of analytical and chemometric tools enables fingerprints of the influence of different parameters characterizing edible plant resources, e.g., identification of variation at annual or seasonal scales, estimation of the degree of pollution and study of the effects of culinary/technological processing. Validated results allow the detection of mislabelled products to preserve the brand reputations of original fruits and their products.