Nutrient Composition and Antioxidant Performances of Bread-Making Products Enriched with Stinging Nettle (Urtica dioica) Leaves

Abstract

Stinging nettle (Urtica dioica) is an edible plant, well-known for its nutritional and nutraceutical properties. Stinging nettle leaves are typically rich in fibers, minerals and vitamins, as well as antioxidant compounds, i.e., polyphenols and carotenoids. Due to these reasons, since ancient times stinging nettle has been widely used in Italy as an ingredient in foods and beverages as a therapeutic agent. This work provides an investigation focused on bread enrichment with nettle leaves and the improvement of bread proximate composition in minerals, fibers and antioxidant compounds during product preparation. The comparison between plain and nettle enriched white bread shows a significant increase in fibers and nutrients, i.e., calcium and copper levels. Nettle enrichment also provides an increase in lutein and β-carotene, as well as in total phenols and antioxidant activity. These last two nutritional elements are remarkably high in enriched bread and it has been found that phenolic concentration increases during breadmaking steps, from kneading to primary dough fermentation and from secondary fermentation of shaped loaves to baking.

Studies on Proximate Composition, Mineral and Total Phenolic Content of Yogurt Bites Enriched with Different Plant Raw Material

“…Previous research has shown that incorporation of rosehip powder in cookies has definitely increased the total phenolic content [54]. A signif-icant increment of total phenolic content was also observed in nettle-enriched bread [50], beetroot juice-enriched yogurt [55] and mulberry leaf extract-enriched yogurt [56].…”

“…The Ca in 100 g of yogurt bites with nettle leaves supplies 28.28% of the RDA. Maietti et al [50] also stated that the addition of nettle to bread can significantly increase the content of calcium. Statistical analysis demonstrated that the differences in the amount of P among all yogurt samples were statistically significant.…”

Bioaccessibility Study of Aflatoxin B1 and Ochratoxin A in Bread Enriched with Fermented Milk Whey and/or Pumpkin

“…reaching in worst case scenarios levels up to 150 µg/kg, exceeding the legal limits [4][5][6][7]. Bread and bakery products are the main foodstuff consumed around the world and are particularly important as a source of carbohydrates, proteins, and vitamins B and E [8]. However, it has been revealed that the baking process does not contribute to the reduction of mycotoxins levels.…”

Indigenous Knowledge and Consumer’s Perspectives of Stinging Nettle (Urtica Simensis) in the Central and Southeastern Highlands of Oromia Regional States of Ethiopia

“…A number of studies reported that young and tender nettle leaves are cooked as vegetable, boiled or added to soups and sauce, dried as spice, used to prepare infusion and decoction, and for salad (Bhat, Rubuluza and Jäger, 2002;Kavalali, 2003 In some recent works on young nettle leaves were used for production of functional foods e.g. nettle enriched egg pasta showed the highest levels for bioavailability of micronutrients and plant metabolites at a lower colonic fermentation time (Bonetti et al, 2016;Marchetti et al, 2018); stinging nettle extract in combination with ε-polylysine enhanced the quality, safety, and shelf life of rainbow trout llets (Azmir et al, 2020); bread-making products enriched with nettle leaves signi cantly increased the level of bers, calcium and copper, and total phenolic content, lutein and β-carotene (Maietti et al, 2021); addition of whole leaves decreased the sensory quality of the bread whereas the extract improved the sensory quality and phenolic acids, avonoids, micro elements, and macro elements (Đurović et al, 2020); addition of freeze dried extract of nettle in chocolates resulted in chocolates with an enhanced and stable polyphenolic pro le during 12 months of storage, furthermore dark chocolates enriched with nettle extracts was preferred over milk and semisweet chocolates (Belščak-Cvitanović et al, 2015). Interestingly, covering hands with cloths and wearing plastic bags were traditional manipulations practiced by the local community to protect themselves from stinging hairs thereby avoiding stinging sensation and collect the young and tender shoots from the plant.…”