No abstract

The present study focuses on the valorization of pomegranate peel waste by extracting bioactive compounds (mainly punicalagin) through pulsed ultrasonic‐assisted extraction. Response surface methodology (RSM) and artificial neural network coupled with multiobjective genetic algorithm (ANN‐MOGA) were used to determine the optimum extraction condition, namely, solvent volume, amplitude, time, and duty cycle. The responses for the optimization process include punicalagin content, ellagic acid, antioxidant activity, total phenolic content (TPC), total flavonoid content, and anthocyanin content. By applying ANN‐MOGA it was found that at optimum condition of 35 ml of solvent, 35% amplitude, 23 min and 100% duty cycle, punicalagin, ellagic acid, antioxidant activity, and TPC was 6.63%, 18.59%, 52%, and 4.23% higher than RSM predicted values, respectively. Thus, the study proves that ANN‐MOGA is an effective tool in predicting maximum punicalagin production from pomegranate peel. The optimization showed a close match between predicted and experimental data. Practical applications Pomegranate peel is a source of bioactive components. With the increase in demand for “clean label” products worldwide, valorization of pomegranate peel could be a potent alternative. This study investigates the ultrasonic‐assisted extraction of major bioactive components from pomegranate peel in order to aid scaling up of the process. Also, the comparison between mathematical tools can give an insight into higher yielding process parameters.

No abstract

Native elephant foot yam starch (EFYS) is highly digestible, and it is not recommendable for consumption by diabetic and obese people. To address this problem, the current study focuses on the amendments in various properties (such as functional properties, whiteness index, amylose content, morphology, and digestion) of EFYS using ultrasonication (US) and US pretreated autoclave (AL) modification with varied time viz. 15, 30, and 45 min. Both the treatments enhanced the water absorption, swelling power, and solubility of EFYS. US‐assisted AL treatment was responsible for increasing the resistant starch (RS) fraction and the highest increment was observed in US‐AL45 EFYS (39.13 ± 1.19 %) as compared to the native counterpart (30.65 ± 1.06 %). Molecular aggregations were observed in all US‐AL EFYS, whereas US treatment broke the agglomerations and increased the intergranular spaces. FTIR analysis revealed the highest increase in ordered to amorphous starch (1047/1022 cm−1) in US‐AL45 EFYS followed by native and others modified EFYS. The highest increase in amylose content was notable in US‐AL45 (10.02 ± 0.08 %) as compared to other native and others treated EFYS. To understand the kinetic behavior of the native and modified EFYS, first‐order kinetics, Michaelis–Menten, Paolucci Jeanjean, Logistic, and Weibull models were applied. The digestogram models highlighted the highest digestibility in native EFYS, preceded by US, US‐AL 15, US‐AL 30, and US‐AL 45 EFYS. US‐AL 45 EFYS showed the highest change in all the functional properties as compared to native and other modified EFYS. Practical applications Owing to the prevalent lifestyle diseases, a continuous evolution in nutritional behaviors has emerged. Although starch imparts consistency and quality to the commercial food products, its high digestibility results in harmful effects to diabetic and obese patients. Elephant foot yam is considered as a unique source of starch and its modification leads to a decrease in enzyme hydrolysis while making it health beneficial. Ultrasonic pretreated autoclaving is one such potential physical modification treatment which can facilitate toward decrease in enzyme digestibility of elephant foot yam starch (EFYS), yet enhancing its swelling properties that in turn leads to the growth of functional food processing industry. The findings of the study highlight the enzyme digestogram modeling of US and US‐AL modified EFYS in order to shed light on the mechanism that regulates them.

Ultrasonic‐assisted extraction of punicalagin from pomegranate peel was investigated. The influence of individual parameters, namely, solvent volume (20–60 mL), amplitude (30–70%), and duty cycle (60–100%) on punicalagin extraction was studied. The optimal condition of extraction was found to be: 40 mL solvent volume, 60% amplitude, and 90% duty cycle. Different kinetic models such as Peleg's model, first order kinetics, power law model, and mass transfer model were used to mathematically describe the extraction mechanism. Initial extraction rate, equilibrium punicalagin concentration, effective diffusivity, model constants, and diffusional exponent have been calculated using these models. The study revealed that first order kinetics (RAdj2=0.964) best fitted the experimental data. Fifteen other hydrolysable tannins were identified using liquid chromatography mass spectrometry in the polyphenolic extract obtained under optimized condition. Practical application There has been a paradigm change to functional food due to prevailing lifestyle diseases. Hence, the interest in the extraction of bioactive compounds from food processing by‐products has increased as a result of various health benefits exhibited by these compounds. Punicalagin (C48H28O30) is an ellagitannin that is predominantly found in pomegranate peel. It is a great natural source of antioxidants, and therefore, it can find its application in products such as food additives, pharmaceuticals (as drugs and supplements), and cosmetics. The finding of this study emphasizes the kinetic investigation of the punicalagin extraction process to describe the mechanisms that drive them.