Organic acid profile of chestnut (Castanea sativa Mill.) as affected by hot air convective drying

Figures & data

Figure 1. Chromatograms of organic acid standard solution (A) and of a chestnut sample extract (B). Peaks: (1) – malic acid; (2) – ascorbic acid; (3) – citric acid; (4) – fumaric acid; and (IS) – internal standard (gallic acid).

Table 1. Figures of merit of the proposed methodology.

			Precision (CV (%), n = 6		10% Standard added
Organic acid	Retention time (min)	r	Intraday	Inter-day	Recovery (mean ± SD)
Malic acid	3.6	0.9999	0.7	2.6	98.2 ± 1.5
Ascorbic acid	3.9	0.9997	0.7	1.1	97.0 ± 1.5
Citric acid	7.3	1.000	1.4	1.7	99.7 ± 1.7
Fumaric acid	8.6	0.9999	2.1	2.7	101.0 ± 2.3

Figure 2. Drying behavior in terms of citric (A), malic (B), ascorbic (C), and fumaric (D) acids along drying time for Longal (∙) and Judia (o) varieties.

Figure 3. Loadings and scores plot resulting from the principal component analysis of organic acids for both varieties.