Effect of Cooking and Reconstitution Methods on the Loss of Bioactive Compounds in Pigmented and Unpigmented Potatoes

Mohammed Z Alam,Gefu Wang-Pruski,Mark Hodges,Martin Dino Kubik,Sherry A E Fillmore,Garry R Hawkins

doi:10.4236/fns.2017.81003

Mohammed Z Alam, Gefu Wang-Pruski + Show 4 more

Open Access

https://doi.org/10.4236/fns.2017.81003

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Abstract

Total phenolics, anthocyanins and antioxidant capacity of five coloured/pigmented (AR2009-10, Adirondack Red, Adirondack Blue, Congo, and POROIPG22-1) and two unpigmented potato genotypes (“Anuschka” and “Russet Burbank”) were assessed in fresh (with and without skin) and commercially processed/cooked/reconstituted products. Ascorbate profiles of the seven genotypes also were investigated using fresh tuber/tissue only. The results showed that genotypes greatly varied in their contents of bioactive compounds. Ascorbate profiles of the genotypes were not associated to any particular flesh colour/pigment. However, the pigmented potatoes had 1.5 to 2.5 times more the phenolics, 2 to 3 times more antioxidant capacity and higher levels of anthocyanins (13.98 to 38.57 mg C3GE-100g FW) compared to unpigmented genotypes. No anthocyanins were detected in the unpigmented potatoes. Significant losses of total phenolics, anthocyanins and total antioxidant capacity were found during peeling (18% - 23%), blanching process (40% - 60%) and further cooking/ reconstitution (7% - 12%) with no prominent genotype differences. Together, 65 to 90% of these bioactive compounds were lost during processing. The results suggested that pigmented potatoes contained higher amounts of total phenolics and anthocyanins and blanching step took away the most of the original bioactive compounds.

Highlights

The results suggested that pigmented potatoes contained higher amounts of total phenolics and anthocyanins and blanching step took away the most of the original bioactive compounds
Anthocyanins and antioxidant capacity in fresh samples of five colour/pigmented and two unpigmented potato genotypes/selections were quantified and how commercial processing/reconstitution processes affect them were investigated in this study
The coloured potatoes had 1.7 to 2.5 times more the phenolics presumably due to the high anthocyanins in them and about 2 to 3 times more antioxidant capacity compared to unpigmented genotypes

Summary

Introduction

The annual diet of an average global citizen in the first decade of the 21st century included about 33 kg of potatoes. Potato represents a secondary staple crop, with an average per capita consumption of around 75 kg∙year−1 in 2007 [4]. Its consumption is around 20 kg∙year−1 per capita but rapid expansion over the past few decades has occurred in southern and eastern Asia [4]. In the Andes of South America, the potato consumption can reach 250 kg∙year−1 per capita. In these regions, potato constitutes the main staple crop, and most households cultivate 10-12 varieties in order to reduce their vulnerability to environmental conditions [5]

Results

Discussion

Conclusion