# Phenolic Content, Antioxidant Capacity and In Vitro Glycemic Index of Traditional Noodle (Erişte) High in Plant‐Based Protein and β‐Glucan Content

## TL;DR

Adding barley and lentil flours to traditional noodles lowers their glycemic index and boosts protein, fiber, and antioxidant content, making them healthier.

## Contribution

This study demonstrates how traditional noodles can be enhanced with plant-based ingredients to meet health claims for beta-glucan and protein.

## Key findings

- Noodles with 45% barley flour met FDA beta-glucan health claim requirements.
- Supplementation with lentil flour increased protein content enough to qualify as 'high protein' under EU regulations.
- All supplemented noodles had medium glycemic index values, down from the high GI of the control wheat-based sample.

## Abstract

Traditional noodle samples (erişte) were supplemented with hull‐less barley and lentil flours as the source of β‐glucan and protein at different ratios and their cooking quality, phenolic content, antioxidant capacity and estimated GI values were evaluated. The estimated GI of control erişte produced from wheat flour was the highest (74.7), while GI of those supplemented with 15%, 30%, 45% barley or lentil flour were 68.7%, 66.0%, 61.2% and 67.5%, 63.8%, 60.6%, respectively. GI values of mixtures of barley and lentils flours (Mix‐1–4 samples) were lower (58.9–61.0). All noodles supplemented with barley and/or lentil flours had medium GI values. The erişte samples supplemented with 45% hull‐less barley flour and Mix erişte samples meet the requirements of FDA health claim (0.75 g β‐glucan per serving). Protein content of control sample was 16.30%, while those supplemented with lentil flour had higher protein contents (18.15%–22.36%). Hence, noodle samples supplemented with 30% and 45% lentil flour can be labeled as “high protein” and all other noodle samples can be labeled as “source of protein” according to EC Regulation because calories which can be received from proteins per serving are > 20% and > 12%, respectively. Significant increases were also observed in phenolic contents and antioxidant capacities of erişte samples supplemented with barley/lentil flours.

Supplementation of erişte with 15%–45% hull‐less barley or lentil flour increased phenolic content, antioxidant capacity, β‐glucan or protein levels, and lowered glycemic index (GI), shifting all samples from high‐ to medium‐GI. Samples with 45% barley flour met FDA β‐glucan health claims. Those with 30% and 45% lentil flour qualify as “high in protein,” while others qualify as “source of protein” under Regulation (EC) 1924/2006. These findings highlight potential of barley and lentils in enhancing functional properties of traditional foods.