Utilization of Pomegranate Fruit Waste as Value Added Drink

Abstract

The present investigation was an attempt to explore the nutraceutical potential of pomegranate peel and bagasse extracts based value added/functional drinks against various metabolic syndromes. Three different pomegranate varieties namely Kandhari, Desi and Badana were nutritionally characterized followed by punicalagin quantification, product development and finally the bio-efficacy trial was carried to evaluate health benefits of respective drinks against hypercholesterolemia and diabetes. The nutritional analysis revealed that pomegranate peel and bagasse are a good source of protein, fiber, fat, potassium (K) and calcium (Ca). For the extraction of polyphenols three types of solvent were used i.e. methanol (50%), ethanol (50%) and ethyl acetate (50%). Amongst tested pomegranate peels & bagasses, Kandhari variety demonstrated the highest total phenolic contents (TPC) [259.05±27.40 & 30.67±4.72 mg/g gallic acid equivalent (GAE)], total flavonoid contents (TFC) [53.53±6.14 & 8.86±1.91 mg/g rutin equivalent (RE)] and 2,2-diphenyl-1-picrylhydrazyl [DPPH (70.66±7.44 & 42.30±5.75%)], likewise, maximum TPC (272.68±17.03 & 31.72±4.75 mg/g GAE), TFC (54.90±3.89 & 8.74±2.48 mg/g RE) and DPPH (72.41±5.87 & 43.34±5.97%) were noticed in methanolic extract of all varieties. The pomegranate peels and bagasses of all varieties were quantified by HPLC that depicted 110.59±8.84 mg/g and 1.77±0.41 mg/g of punicalagin, respectively. Afterwards, in product development phase, three types of value added drinks were formulated as drink containing pomegranate peel extract (D1), drink containing bagasse extract (D2) alongside with control (D0) for comparison purpose. The prepared drinks were subjected to physicochemical characterization during two months storage interval. In this milieu, storage intervals and treatments imparted significant effect on color tonality parameters of value added drinks. Moreover, storage interval substantially affected pH and acidity of drinks except for total soluble solids (TSS). Sensory scores of formulated value added drinks decreased with the progression of storage time however, the scores remained within acceptable range throughout the course of study. The efficacy trial was conducted on male Sprague Dawley rats. Accordingly, three types of studies were designed i.e. study I (normal rats), study II (hypercholesterolemic rats) and study III (diabetic rats). Additionally, each study was further divided into three groups G-1, G-2 and G-3 depending on the drinks i.e. D0, D1 and D2 that they were subjected to respectively. The body weights of experimented rats were affected substantially due to the application of value added drinks in all studies. The pomegranate peel extract based drink (D1) resulted in maximum decline in serum cholesterol values during study I, II & III by 3.09, 14.52 & 10.26% likewise a pronounced reduction in LDL and triglyceride levels was evaluated due to utilization of drink D1 (3.75, 14.86 & 11.75% and 3.12, 9.99 & 7.05%) followed by D2 (2.02, 10.74 & 7.72% and 2.89, 5.63 & 4.22%), respectively. Similarly, HDL increases significantly due to administration of value added drinks in study II and III. As far as antidiabetic perspectives are concerned, a substantial decline (p˂0.05) in serum glucose level was observed in study II (7.50 & 5.11%) and study III (13.28 & 8.71%) due to consumption of drink D1 & D2, correspondingly. Nevertheless, a substantial increase in insulin level was documented in D1 (5.66 & 8.74%) and D2 (3.38 & 4.37%) administrated groups during study II & III. Moreover, for the assessment of anti-oxidative markers, glutathione level was enhanced and thiobarbituric acid reactive substances (TBARS) level was reduced by utilization of value added drinks. The results of liver and kidney functioning tests as well as hematological attributes ensured the safety of value added drinks. It is inferred from the present exploration that Kandhari pomegranate peel was more effective as compared to Kandhari bagasse based drinks to mitigate hypercholesterolemia and diabetes.