Characteristics of white, yellow, purple corn accessions: phenolic profile, textural, rheological properties and muffin making potential

Physicochemical, antioxidant, phenolic profile and muffin-making properties of white, yellow and purple corn accessions were evaluated. HPLC analysis revealed the presence of ferulic acid, quercetin, sinapic acid, gallic acid and protocatechuic acid in different corn accessions. Ferulic acid was the major phenolic acid present in all accessions. Total phenolic content (TPC), DPPH and ABTS inhibition ranged from 903 to 1843 µg GAE/g, 0.73-0.89 and 3.81-4.92 µM trolox/mg, respectively. Purple accessions had higher TPC than yellow and white accessions. Pasting profiles of different accessions revealed high thermal stability indicated by low breakdown viscosity. Muffin-making properties were determined as batter rheology and muffin specific volume, texture and sensory analysis. Storage modulus (G') and loss modulus (G″) of batters for white colored exhibited the highest while yellow colored had the lowest value. Firmness and TPC of muffins ranged from 3.1 to 5.9 N and 811-1406 µg GAE/g, respectively. Muffin cohesiveness and chewiness were correlated positively, whereas firmness was negatively related to paste viscosities. Antioxidant activity was correlated to phenolic content of the muffins. Sensory analysis revealed that muffins prepared from yellow corn accession (IC447648) were highly acceptable, while those made from purple corn (IC447644) were not liked much.

Effect of fermented and unfermented buckwheat flour on functional properties of gluten-free muffins

Selected functional properties of four types of gluten-free muffins made of unfermented and fermented (by Lactobacillus plantarum) buckwheat flour in comparison with control muffins made using commercial gluten-free corn flour were evaluated in this study. The proximate chemical composition, antioxidant capacity analysed by ABTS, photochemiluminescence and cyclic voltammetry assays, and inhibitory activity against protein glycation in vitro in BSA/Glu systems were investigated. The content of the total phenolic compounds, available lysine, furosine, free and total FIC, browning index and antioxidant capacity of buckwheat-enhanced gluten-free muffins were higher compared to the control samples. Gluten-free muffins made of the fermented buckwheat flour showed a significantly higher antioxidant capacity, an increased activity against AGEs formation and an increased available lysine content, as well as a higher FAST index and browning index as compared to the muffins obtained with unfermented buckwheat flour. The study showed that buckwheat flour fermented by L. plantarum could be used as an ingredient for improving the functional properties of gluten-free muffins.

Development of eggless gluten-free rice muffins utilizing black carrot dietary fibre concentrate and xanthan gum

Gluten-free muffins are generally made from purified flours and starches (from non-gluten sources) which are deficient in dietary fibre and have poor quality attributes. In this regard, the present work was undertaken to explore application of black carrot pomace dietary fibre concentrate (BCF) and xanthan gum (XG) in gluten-free rice muffins. Physicochemical properties of BCF and rice flour were studied. BCF was incorporated at three levels (3, 6 and 9 %) in rice flour, while XG was added at 0.5 % level to study their effect on muffin batters and physicochemical properties of muffins. BCF showed higher water absorption and oil absorption capacities than rice flour. Incorporation of BCF and XG increased flour paste viscosities and batter viscoelasticity. Incorporation of BCF increased total dietary fibre content (TDF) and decreased the L* and b* values, water activity (aw), specific volume and firmness. On the other hand, XG improved appearance and specific volume of the rice muffins prepared with and without BCF. Muffins prepared with 6 % BCF incorporation and XG were the most acceptable. This study demonstrated that BCF and XG can be used as viable functional ingredients in the preparation of gluten-free muffins.