Identification and Quantification of Stilbenes (Piceatannol and Resveratrol) in Passiflora edulis By-Products

Recently, studies on the by-products from the food industry, such as passion fruit seeds, have significantly increased, as these can have an added value, due to their properties, such as potential antioxidant activity. This study was conducted to determine the presence of piceatannol and resveratrol in various extracts of passion fruit (Passiflora edulis) seeds from Madeira Island and a commercial passion fruit oil was used as reference. The commercial oil and the extracts that were obtained by traditional Soxhlet method with ethanol and acetone did not reveal the presence of the two stilbenes, piceatannol and resveratrol. However, the extracts that were obtained by the ultrasound method showed significant amounts of piceatannol and resveratrol when compared with the commercial oil. The presence of these compounds indicates that this oil could have potential application in cosmetic and pharmaceutical industries, due to their proven antioxidant and anti-aging properties.

Identification of Passion Fruit Oil Adulteration by Chemometric Analysis of FTIR Spectra

Passion fruit oil is a high-value product with applications in the food and cosmetic sectors. It is frequently diluted with sunflower oil. Sunflower oil is also a potential adulterant as its addition does not notably alter the appearance of the passion fruit oil. In this paper, we show that this is also true for the FTIR spectrum. However, the chemometric analysis of the data changes this situation. Principal component analysis (PCA) enables not only the straightforward discrimination of pure passion fruit oil and adulterated samples but also the unambiguous classification of passion fruit oil products from five different manufacturers. Even small amounts—significantly below 1%—of the adulterant can be detected. Furthermore, partial least-squares regression (PLSR) facilitates the quantification of the amount of sunflower oil added to the passion fruit oil. The results demonstrate that the combination of FTIR spectroscopy and chemometric data analysis is a very powerful tool to analyze passion fruit oil.

AVALIAÇÃO DE DIFERENTES MÉTODOS CROMATOGRÁFICOS NA DETERMINAÇÃO DE ÁCIDOS GRAXOS EM SEMENTES DE MARACUJÁ (Passiflora edulis f. flavicarpa)

Determinou-se a composição de ácidos graxos, por cromatografia em fase gasosa, do óleo da semente do maracujá amarelo (Passiflora edulis f. flavicarpa), em três diferentes tamanhos de frutos (tipo 1 = 1215 cm; tipo 2 = 710 cm; tipo 3 = 56 cm). O rendimento das sementes em relação ao peso dos frutos para os tipos 1, 2 e 3 (5,18; 5,83 e 5,31%) e para a polpa dos tipos 1 e 3 (12; 17 e 12,67%) não apresentou diferença entre os tamanhos analisados, com exceção do tipo 2 (14,03%) para polpa que evidenciou maior rendimento. A composição em ácidos graxos do óleo da semente do maracujá amarelo, nos três diferentes tamanhos, mostrou predominância de ácidos graxos oléico e linoléico. O método mais adequado para a determinação da composição de ácidos graxos do óleo do maracujá foi o Cd 14c94/ coluna SP 2340 da American Oil Chemists’ Society. Abstract Fatty acids composition was determined in three different sizes (type 1=1215 cm; type 2=710 cm; type 3=56cm) of yellow passion fruit (Passiflora edulis f. flavicarpa) oil using gas chromatography. The seed yield in terms of fruit weight to types 1, 2 and 3 (5,18; 5,83 and 5,31%) and fruit pulp to types 1 and 3 (12,17 and 12,67%) didn’t present differences between the sizes analyzed with the exception of fruit pulp type 2 (14,03%) that showed the highest yield. The fatty acids composition of yellow passion fruit oil, in three different sizes, showed a predominance of oleic and linoleic acids. The more suitable methodology for passion fruit oil fatty acids determination was AOCS Cd 14c94/ column SP 2340.