Effect of processing on structural, thermal, and physicochemical properties of dietary fiber of culinary banana bracts

Abstract

Dietary fiber (DF) of culinary banana bract was extracted using alkaline extraction (alkaline extracted DF, AEDF) and ultrasound‐assisted extraction in combination with alkaline extraction (ultrasound‐assisted extracted DF, UEDF). The extracted DFs were compared for their composition, structural, thermal, and functional properties. Extraction condition of UEDF was optimized for maximizing the yield through response surface methodology. The maximum yield of DF obtained was 71.05%. Higher total DF (83.38 g/100 g) was detected in UEDF than AEDF. Higher crystallinity (25.86%), regular honeycomb structure, lesser particle size (<0.5 µm), and greater thermal stability was evident in UEDF, when compared to AEDF. Presence of 5‐hydroxymethylfurfural and β‐D‐glucopyranose was detected in UEDF. Moreover, better water‐holding capacity, oil‐holding capacity, and water‐swelling capacity with improved functional properties viz., α‐amylase retardation index and glucose‐absorption capacity were obtained in UEDF than AEDF. The results indicated that UEDF was better functional ingredient as compared to AEDF. Practical applications Culinary banana bract is byproduct of banana production and a rich source of antioxidant dietary fiber (DF) (Begum & Deka, 2019). This antioxidant DF has high importance, as it is related to many health beneficial effects, mainly in the prevention and management of chronic and degenerative diseases. The extracted DF using ultrasound‐assisted extraction (UEDF) exhibited high yield with purity, improved structural properties, higher thermal stability, and better physicochemical properties. Moreover, the study of functional properties such as α‐amylase retardation index and glucose‐absorption capacity revealed that UEDF effectively inhibited the contact between α‐amylase and starch and thereby, decreased the amount of glucose in serum. Hence, UEDF is a better functional ingredient and can be used to develop low calorie and fiber‐rich dietetic snacks.

Bread fortified with dietary fibre extracted from culinary banana bract: its quality attributes and in vitro starch digestibility

“…Our recent study has shown that the extracted DF (ultrasound‐assisted extracted DF) with higher WHC (water holding capacity), α‐AAIR (α‐amylase retardation index) and GAC (glucose absorption capacity). The smaller particle size and crystalline structure of extracted DF inhibited the contact between α‐amylase and starch and hence, decreased the amount of glucose in serum (Begum & Deka, ). Lower carbohydrate digestibility with lower GI value obtained for pasta and extruded cereal foods with added inulin as a source of soluble DF (Brennan & Samyue, ; Brennan et al , ).…”

Ultrasound assisted extraction (UAE) of bioactive compounds from fruit and vegetable processing by-products: A review

“…Similarly , Al-Dhabi et al [3] ) for the extraction of phenolic compounds from Spent coffee ground used Soxhlet extraction system with petroleum ether to defat the samples. Begum and Deka [10] deoiled banana bract using n-hexane, stirring them at 150 rpm for 15 min thereafter centrifuging the sample at 4000 rpm for 20 and finally drying at 50 °C.…”

“…UAE of dietary fiber from Citrus Changshan-huyou peels [16] and apple pomace [43] shows better yield, consumed less time and required low temperature as compared to conventional solvent extraction. Similarly, UAE of dietary fiber from culinary banana bract, papaya peel and soyabean residue exhibited higher yield, purity, thermal stability, water-holding, oil-holding and swelling capacities than alkaline extracted dietary fiber [89] , [10] , [78] . UAE dietary fiber contained higher percentages of essential amino acids and essential trace elements while the crystallinity less than alkaline dietary fiber.…”

Novel approach for the development of dietary fibre‐anthocyanin enriched functional bread from culinary banana bract

“…The methodology of extraction of DF under optimised condition has been explained in our previous study (Begum et al ., 2019; Begum & Deka, 2019b). The dried culinary banana bract (CBB) was deoiled using n‐hexane.…”