Quince (Cydonia oblonga Miller) Fruit Characterization Using Principal Component Analysis

Abstract

This paper presents a large amount of data on the composition of quince fruit with regard to phenolic compounds, organic acids, and free amino acids. Subsequently, principal component analysis (PCA) is carried out to characterize this fruit. The main purposes of this study were (i) the clarification of the interactions among three factors-quince fruit part, geographical origin of the fruits, and harvesting year-and the phenolic, organic acid, and free amino acid profiles; (ii) the classification of the possible differences; and (iii) the possible correlation among the contents of phenolics, organic acids, and free amino acids in quince fruit. With these aims, quince pulp and peel from nine geographical origins of Portugal, harvested in three consecutive years, for a total of 48 samples, were studied. PCA was performed to assess the relationship among the different components of quince fruit phenolics, organic acids, and free amino acids. Phenolics determination was the most interesting. The difference between pulp and peel phenolic profiles was more apparent during PCA. Two PCs accounted for 81.29% of the total variability, PC1 (74.14%) and PC2 (7.15%). PC1 described the difference between the contents of caffeoylquinic acids (3-O-, 4-O-, and 5-O-caffeoylquinic acids and 3,5-O-dicaffeoylquinic acid) and flavonoids (quercetin 3-galactoside, rutin, kaempferol glycoside, kaempferol 3-glucoside, kaempferol 3-rutinoside, quercetin glycosides acylated with p-coumaric acid, and kaempferol glycosides acylated with p-coumaric acid). PC2 related the content of 4-O-caffeoylquinic acid with the contents of 5-O-caffeoylquinic and 3,5-O-dicaffeoylquinic acids. PCA of phenolic compounds enables a clear distinction between the two parts of the fruit. The data presented herein may serve as a database for the detection of adulteration in quince derivatives.

Drying method effects on the antioxidant activity of quince (Cydonia oblonga Miller) tea

“…They are similar to those reported by other researchers [Sharma et al 2011, Silva et al 2005, Rodriguez-Guisado et al 2009 ±3.57 mg tannic acid/g of sample, respectively. As can be seen, oven-dried and quince peel contained higher amounts of phenolics than sun-dried and fl esh quinces, respectively.…”

“…Quince fruit (Cydonia oblonga Miller) is not appreciated fresh due to its pulp hardness, bitterness and astringency. But in the processed form, it is in high demand for consumption [Silva et al 2002[Silva et al , 2005. One of these processes is drying.…”

Chemical and antioxidative assessment of dietary turnip (Brassica rapa var. rapa L.)

“…This association is often attributed to the antioxidant phytochemicals, namely phenolic compounds and organic acids (Liu, 2003;Pulido, Bravo, & Saura-Calixto, 2000;Silva et al, 2004). These compounds are also known to contribute to the organoleptic characteristics of fruits and vegetables (Vaughan & Geissler, 1997) and have been widely applied for their quality control Silva et al, 2005;Sousa et al, 2005).…”

Chemical characteristics of fruits of some selected quince (Cydonia oblonga Mill.) cultivars

“…flavonoids quercetin, rutin, kaemp-ferol etc. (Silva et al 2005), and also from increased levels of vitamin C (Tetera 2006). Quinces are important also for the canning industry, especially due to their high contents of pectins (Kyzlink 1990;Forni et al 1994).…”