Total Content of Phenolics and Antioxidant Activity in Crispbreads with Plant By-product addition

Abstract

Abstract. Vegetable processing in food industry results in significant amount of by-products -peel, mark, bark, seeds still rich in bioactive compounds. Apple, carrot and pumpkin peel and mark may be used for production of crispbreads as functional ingredients. The objective of this study is to investigate the stability of total phenolic content (TPC) and antioxidant activity after high temperature and short time (HTST) extrusion cooking of a wheat and rice-based crispbreads with addition of apple, carrot and pumpkin by-products obtained after juice extraxtion and dried. Raw materials for crispbread production were wheat flour, rice flour, wheat bran (72%, 24% and 4% respectively) with addition of microwave-vacuum dried by-product powder in different amount (5%, 10%, 15%, 20%). Extrusion process was performed by using a laboratory singlescrew extruder GÖTTFERT 1 screw Extrusiometer L series (Germany). Total phenolic content (TPC) was determined using the Folin Ciocalteu method. Antioxidant activity was evaluated by free radical 2, 2-diphenyl-1-picrylhydrazyl (DPPH) antioxidant scavenging activity using a modified colorimetric method. Comparing different raw formulations, it was observed that the TPC of the apple by-product flour was significantly higher (p < 0.05) than in carrot and pumpkin flour. TPC in cereal-based crispbread was 36.06±1.15 before extrusion and 13.90±1.01 mg GAEg-1 DW (milligram Gallic acid equivalent per 100 g of dry weight (mg GAE 100 g -1 DW) after extrusion. Addition of apple BPF increased TPC in crispbreads to 106.25±2.08, carrot BPF 84.73±3.45 and pumpkin BPF to 108.82±1.04 mg GAEg -1 DW. Antioxidant activity of control sample was 1.07±0.01mg TE (Trolox equivalents) g -1 DW but in samples with addition of 20% apple by-products, it reached 3.77±0.02 TE g -1 DW for samples wih 20% carrot by-products reached 2.52±0.03TE g -1 DW and for samples wih 20% pumpkin by-products reached 3.77±0.02 TE g -1 DW.

Assessment of rheological and quality characteristics of bread made by the addition of ginger powder in wheat flour

“…Similar trend was reported by Pekmez & Yılmaz (2018) for flat bread enriched with black carrot fiber content at different levels. The given outcomes are also in accordance with the findings of Konrade & Klava (2017) an increasing trend of phenolic content in crispbread by adding carrot, pumpkin and apple dry extracts. Total phenolic content in fresh carrot were always higher than dried form (microwave and sundried).…”

“…The highest value (0.485 mg GAE/g DW) was recorded in 6% ginger powder bread and minimum value showed in 0% (0.143 mg GAE/g DW) ginger powder bread. Similar results reported by Almasodi (2018) and Konrade & Klava, (2017) whereby TPC of bread was increased by the addition of ginger flour.…”

Reactions of anthocyanin rich in maize genotypes to low temperature treatments according to photosynthesis, gas exchange properties, and bio-active compounds

“…Total phenolic content (TPC): Total phenolic content was determined following the procedures of Konrade and Klava (2017), with some modifications. First, a 0.5 g ground sample was extracted using 5 ml methanol (80%) for 48 h, then 2.5 ml of Folin-Ciocalteu reagent (diluted 10 times) was added.…”

Utilization of Manalagi Apple Pomace and Its Effect on Dietary Fibre, Texture and Sensory of Waffle Cone

“…Scones containing increased amount of freeze-dried apple pomace resulted in increased of total dietary fibre up to 18%. In wheat-rice crispbread, addition of 5-15% apple pomace powder increased the total dietary fibre content from 9.39 to 15.89 g/100 g, while in rye crispbread, the same amount of addition increased the total dietary fibre from 15.8 to 19.8 g/100 g [5]. In Indonesia, Malang is widely known as one of apple cultivation centers that produces different varieties of Malang apple (Malus sylvestris Mill), namely Manalagi, Rome Beauty, Anna and Wangling [2].…”