Storage Conditions for ‘Barton’ Pecan: Impact of Moisture Content and Temperature on Quality Maintenance and Volatile Compounds Profile

• Published in: Applied Fruit Science 2024-06, Vol.66 (3), p.941-952
• Main Authors: Thewes, Flavio Roberto, Both, Vanderlei, Brackmann, Auri, Thewes, Fabio Rodrigo, Junior Soldateli, Francis, Mallmann Wendt, Lucas, Fronza, Diniz
• Format: Article
• Language: English
• Subjects: Acidity; Agriculture; Biomedical and Life Sciences; cell respiration; Climatic conditions; Color; Drying; fruits; Gas chromatography; Hexanal; Life Sciences; Low temperature; Moisture content; Original Article; Pecan nuts; pecans; peroxide value; Plant Sciences; Solid phase methods; Storage conditions; Storage temperature; Temperature; Volatile compounds; Water content
• ISSN: 2948-2623; 0014-0309; 2948-2631; 1439-0302
• DOI: 10.1007/s10341-024-01068-x

During harvest, producers may have difficulty in drying pecan to the desired moisture content (MC), either because of climatic conditions or due to the high demand of drying systems, resulting in the storage of pecan with higher kernel MC. Therefore, the objective of the present study was to evaluate the effects of ‘Barton’ pecan with 6% and 4% MC stored under different temperatures (20 °, 10 °, and 1 °C) on pecan kernel color, incidence and severity of internal browning (IB), acidity, peroxide value (PV), and volatile compounds profile after 8 and 12 months of storage. After storage, pecans were shelled and kernel color was evaluated (hue angle). Pecan stored at 1 °C had the highest hue angle (yellowish color) and lower parameter a* (less reddish), followed by 10 °C, regardless of MC, which had a lesser effect on color than storage temperature. Storage at 20 °C resulted in the highest IB incidence and severity, and respiration rate, with a positive effect of reduced MC at this temperature. Lower storage temperatures were also effective in reducing IB. Lower acidity and PV were observed with storage at lower temperatures (10 ° and 1 °C) and with reduced MC (4%). Gas chromatography (HS-SPME-GC/MS) was used to determine the volatile compounds (VC). The adoption of lower temperatures (10 ° and 1 °C) or lower MC (4%) resulted in a lower abundance of hexanal. In general, the adoption of 10 ° and 1 °C effectively maintained the quality of pecan during 12 months, even those stored with high MC (6%).