Effects of Pre-germination Treatment on the Phytate and Phenolic Contents of Almond Nuts

Document Type : Research Article

Authors

1 Food Science & Nutrition Group, School of Chemical & Life Sciences, Nanyang Polytechnic, Nanyang, Singapore

2 1 Food Science & Nutrition Group, School of Chemical & Life Sciences, Nanyang Polytechnic, Nanyang, Singapore 2 Centre for Functional Food & Human Nutrition, School of Chemical & Life Sciences, Nanyang Polytechnic, Nanyang, Singapore

Abstract

This study examined if pre-germination altered the water content and water activity, contents of phytate, total phenolic, (±)-catechin, quercetin and total antioxidant capacity of almond  (Prunus dulcis)kernel. Raw almond kernels were submerged for 15 hours in water, 0.02 mol dm-3 phosphate buffer solution (pH 5.0) and 0.02 mol dm-3 phosphate buffer solution (pH 7.0) at 25 and 40ºC, respectively. The content and activity of water in the kernels before and after the pre-germination treatments were measured by oven drying and dew point water analysis, respectively. The total phenolic and phytic acid contents of the kernels were quantified by using Folin-Ciocalteu and a published spectrophotometric assay, respectively. (±)-Catechin and quercetin contents in the almond kernels were determined using gas-chromatography mass spectrometry. The total antioxidant capacity of the kernels were measured by 2,2’-diphenyl-1- picrylhydrazyl assay. Treatment with water, PBS pH 5 and PBS pH 7 significantly increased the water, total phenolic, (±)-catechin contents and total antioxidant capacity of the almond kernels regardless of the treatment temperatures (25 or 40°C). The phytic acid and quercetin contents were significantly elevated after the  three treatments at 40°C. The total phenolic, (±)-catechin, quercetin and phytate contents in the almond kernels contributed significantly to its antioxidant property. Our results suggested that the phytochemical compositions of the almond kernels changed during pre-germination. The temperature and pH of the medium exert differential influence on the phytochemical compositions of the pre-germinated almond kernels.

Keywords

References

Actis-Goretta L, Ottaviani JI, Fraga CG (2006) Inhibition of angiotensin converting enzyme activity by flavanol-rich foods. Journal of Agricultural and. Food Chemistry. 54(1), 229-234.
Brune M, Rossander L, Hallberg L (1989) Iron absorption: no intestinal adaptation to a high-phytate diet. American Journal of Clinical Nutitionr. 49(3), 542-545.
Carlson D, Poulsen HD (2003) Phytate degradation in soaked and fermented liquid feed—effect of diet, time of soaking, heat treatment, phytase activity, pH and temperature. Animal Feed Science and Technology. 103(1), 141-154.
Cheryan M, Rackis JJ (1980) Phytic acid interactions in food systems. Critical Review in Food Science and Nutrition. 13(4), 297-335.
Dost K, Tokul O (2006) Determination of phytic acid in wheat and wheat products by reverse phase high performance liquid chromatography. Analytical Chimical Acta. 558(1–2), 22-27.
Duthie G, Crozier A (2000) Plant-derived phenolic antioxidants. Curentr Opinion in Lipidology. 11, 43-47.  Retrieved from 20060306 (4) abst.
Fuzfai Z, Molnar-Perl I (2007) Gas chromatographic-mass spectrometric fragmentation study of flavonoids as their trimethylsilyl derivatives: Analysis of flavonoids, sugars, carboxylic and amino acids in model systems and in citrus fruits. Journal of Chromatography A,1149(1), 88-101.  Retrieved from 20070819(2).
Graf E, Empson KL, Eaton JW (1987) Phytic acid. A natural antioxidant. Journal of Biological Chemistry. 262(24), 11647-11650. Retrieved from.
Gujral HS, Sharma P, Kumar A, Singh B (2012) Total phenolic content and antioxidant activity of extruded brown rice. International Journal of Food Properties.15(2), 301-311.
Harland BF, Morris ER (1995) Phytate: a good or a bad food component? Nutrition Research. 15(5), 733-754.
Haug W, Lantzsch HJ (1983) Sensitive method for the rapid determination of phytate in cereals and cereal products. Journal of the Science of Food and Agriculture.34(12), 1423-1426.
Kammerer D, Kramer M, Carle R (2012) Phenolic Compounds. In L. M. Nollet & F. Toldrá (Eds.), Food analysis by HPLC (Third ed., Vol. 100, pp. 717). CRC Press.
Kornsteiner M, Wagner KH, Elmadfa I (2006) Tocopherols and total phenolics in 10 different nut types. Food Chemistry.98(2), 381-387.
Larsson M, Sandberg AS (1995) Malting of oats in a pilot-plant process. Effects of heat treatment, storage and soaking conditions on phytate reduction. Journal of  Cereal Science. 21(1), 87-95.
Lestienne I, Icard-Vernière C, Mouquet C, Picq C, Trèche S (2005) Effects of soaking whole cereal and legume seeds on iron, zinc and phytate contents. Food Chemistry.89(3), 421-425.
Liang J, Han BZ, Nout MR, Hamer RJ (2008) Effects of soaking, germination and fermentation on phytic acid, total and in vitro soluble zinc in brown rice. Food Chemistry. 110(4), 821-828.
Lin PY, Lai HM (2006) Bioactive compounds in legumes and their germinated products. Journal of Agricultural and Food Chemistry. 54(11), 3807-3814.
Lopez HW, Leenhardt F, Coudray C, Remesy C (2002) Minerals and phytic acid interactions: is it a real problem for human nutrition? International Journal of Food Science & Technology. 37(7), 727-739.
Reddy N, Sathe S, Salunkhe D (1982) Phytates in legumes and cereals. Advance in Food Research. 28(1), 92-94.
Shallan MA, El-Beltagi HS, Mona A, Amera T (2010) Chemical Evaluation of Pre-germinated Brown Rice and Whole Grain Rice Bread. Electronic Journal of Environmental, Agricultural & Food Chemistry.9(5), 958-971.
Sharma P, Gujral HS (2010) Antioxidant and polyphenol oxidase activity of germinated barley and its milling fractions. Food Chemistry. 120(3), 673-678.
Shibuya N (1984) Phenolic acids and their carbohydrate esters in rice endosperm cell walls. Phytochemistry. 23(10), 2233-2237.
Swain T, Hillis W (1959) The phenolic constituents of Prunus domestica. I. The quantitative analysis of phenolic constituents. Journal of Science of  Food and Agriculture. 10(1), 63-68.
Tian S, Nakamura K, Kayahara H (2004) Analysis of phenolic compounds in white rice, brown rice, and germinated brown rice. Journal of Agricultural and Food Chemistry. 52(15), 4808-4813.
Villano D, Fernandez-Pachon MS, Moya ML, Troncoso AM, Garcia-Parrilla MC (2007) Radical scavenging ability of polyphenolic compounds towards DPPH free radical. Talanta. 71(1), 230-235.  Retrieved from 20070413(1).
Zhou JR, Erdman Jr, JW (1995) Phytic acid in health and disease. Critical Review in Food Science and Nutrition. 35(6), 495-508.
Journal of Nuts
Volume 08, Issue 01
Spring 2017
Pages 73-80

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