Effect of Growth Stages and Lactic Acid Fermentation on Anti-Nutrients and Nutritional Attributes of Spinach (Spinacia oleracea)

authored by

Adila Naseem, Saeed Akhtar, Tariq Ismail, Muhammad Qamar, Dur-e-shahwar Sattar, Wisha Saeed, Tuba Esatbeyoglu, Elena Bartkiene, João Miguel Rocha

Abstract

Spinach (Spinacia oleracea) is a winter-season green, leafy vegetable grown all over the world, belonging to the family Amaranthus, sub-family Chenopodiaceae. Spinach is a low-caloric food and an enormous source of micronutrients, e.g., calcium, folates, zinc, retinol, iron, ascorbic acid and magnesium. Contrarily, it also contains a variety of anti-nutritional factors, e.g., alkaloids, phytates, saponins, oxalates, tannins and many other natural toxicants which may hinder nutrient-absorption. This study was aimed at investigating the effect of fermentation on improving the nutrient-delivering potential of spinach and mitigating its burden of antinutrients and toxicants at three growth stages: the 1st growth stage as baby leaves, the 2nd growth stage at the coarse stage, and the 3rd growth stage at maturation. The results revealed the significant (p < 0.05) effect of fermentation on increasing the protein and fiber content of spinach powder from 2.53 to 3.53% and 19.33 to 22.03%, respectively, and on reducing total carbohydrate content from 52.92 to 40.52%; the effect was consistent in all three growth stages. A significant decline in alkaloids (6.45 to 2.20 mg/100 g), oxalates (0.07 mg/100 g to 0.02 mg/100 g), phytates (1.97 to 0.43 mg/100 g) and glucosinolates (201 to 10.50 µmol/g) was observed as a result of fermentation using Lactiplantibacillus plantarum. Fermentation had no impact on total phenolic content and the antioxidant potential of spinach, as evaluated using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric-reducing antioxidant power (FRAP) assays. This study proposes fermentation as a safer bioprocess for improving the nutrient-delivering potential of spinach, and suggests processed powders made from spinach as a cost-effective complement to existing plant proteins.

Organisation(s)

Institute of Food Science and Human Nutrition
Molecular Food Chemistry and Food Development

External Organisation(s)

Bahauddin Zakariya University
Lithuanian University of Health Sciences (LSMU)
Universidade Católica Portuguesa (UCP)
Universidade do Porto

Type

Article

Journal

Microorganisms

Volume

11

ISSN

2076-2607

Publication date

19.09.2023

Publication status

Published

Peer reviewed

Yes

ASJC Scopus subject areas

Microbiology (medical), Virology, Microbiology

Electronic version(s)

https://doi.org/10.3390/microorganisms11092343 (Access: Open)