Texture properties, crude fat, fatty acid profiles, total soluble solids, and total polyphenols for 21 pecan varieties and the effects of harvest year

Authors: YUSUFALI, ZAHRA - Texas Woman'S University; LIU, XUEJUN - Texas Woman'S University; Wang, Xinwang; Kubenka, Keith; DU, XIAOFEN - Texas Woman'S University

Submitted to: ACS Food Science and Technology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 9/18/2023
Publication Date: 10/6/2023
Citation: Yusufali, Z., Liu, X., Wang, X., Kubenka, K.A., Du, X. 2023. Texture properties, crude fat, fatty acid profiles, total soluble solids, and total polyphenols for 21 pecan varieties and the effects of harvest year. ACS Food Science and Technology. https://doi.org/10.1021/acsfoodscitech.3c00216.
DOI: https://doi.org/10.1021/acsfoodscitech.3c00216

Interpretive Summary: The primary objective of the USDA ARS Pecan Breeding Program is to develop superior pecan cultivars. Over the last nine decades, the program has released 32 pecan cultivars that have proven beneficial to pecan growers in the United States. These cultivars have contributed to increased profits and enhanced competitiveness in the international market. However, the released cultivars from the Pecan Breeding Program thus far have not included vital nut quality information that is of great importance to pecan growers and consumers. This work conducted an analysis of nut texture properties and nutrient content across a subset of pecan varieties, including natives, improved cultivars, and new breeding lines. This research provides valuable insights into the released pecan cultivars for both pecan growers and consumers, as well as for pecan breeders aiming to develop high quality new cultivars for productive use by U.S. pecan producers.

Technical Abstract: Pecan (Carya illinoinensis) is one of the most important nut crops due to kernel nutritional composition and unique flavor (aroma and taste); however, no research has focused on taste relevant compositions and their variation in variety and harvest year. This study aimed to quantify 21 free amino acids, four 5'-nucleotides, three soluble sugars, and four organic acids in 26 samples with seven varieties across two harvest years. The identified free amino acids included all nine essential, nine non-essential, and three uncommon. The total free amino acid in 26 samples ranged from 59.4 – 116.2 mg/100g whole kernel. The most dominant free amino acids were Glu and Asp (contribute umami taste; 12.07 – 39.84 and 6.85 – 26.05 mg/100g) in all samples. The total 5'-nucleotides ranged from 16.49 – 49.68 mg/100g whole kernel. The most abundant 5'-nucleotides was IMP (umami enhancer; 5.00 – 20.66 mg/100g). The total sugars ranged from 2.27 – 5.60 g/100g whole kernel, with primary content of sucrose (trace – 5.60 g/100g) and only a few varieties containing fructose and glucose. Total organic acids ranged from 247.94 – 473.13 mg/100g whole kernel. The most abundant organic acids was citric acid (37.86 – 245.83 mg/100g). All varieties and the harvest years showed a significant difference in these compositional analyses. Variety different was a determine factor, followed by harvest year. This study can potentially lead to better tasting pecan varieties in pecan breeding program that can benefit consumers and producers.