Standardization and Development of Underutilized Pear and Plum Based Functional Food Products from Indigenous Himalayan Region of Himachal Pradesh

Abstract

viii newlineABSTRACT newlineThe present study was carried out for the standardization and development of underutilized pear (Pyrus pyrifolia) and plum (Prunus domestica) based functional food products from the indigenous Himalayan region of Himachal Pradesh. The fresh fruits of pear and plum were collected from the Himalayan region (altitude 1580m above mean sea level). The leaves, bark and rhizomes of herbs viz. arjuna (Terminalia Arjuna), ginger (Zingiber officinale) and mint (Mentha arvensis) were also collected from the local regions of Solan, Himachal Pradesh, India. Assessment of phytochemical and antioxidant potential of fruit and herb extracts was carried out. The antioxidant activity was estimated by DPPH, FRAP and nitric oxide scavenging assays. The total phenolic content was found to be 159.86±2.91 and 145.56±2.43 and#956;g/ml gallic acid equivalents and flavonoid content was found to be 48.69±1.90 and 284.27±2.16 and#956;g/ml rutin equivalents for pear and plum, respectively. Whereas in herbs, the total phenolic content was found to be 191.35± 3.62, 174.45±5.78 and 142.60±3.58 and#956;g/ml gallic acid equivalents and flavonoid content was found to be 312.26±6.24, 97.45±6.02 and 77.74±4.01 and#956;g/ml rutin equivalents for arjuna, zinger and mint, respectively. The IC50 value of DPPH scavenging activity of fruit extract was found to be 17.37 and 9.47 and#956;l/ml and for FRAP activity it was 15.51 and 6.13 and#956;M Fe (II) equivalents. The IC50 value of nitric oxide scavenging activity was 21.49 and 30.11 and#956;l/ml for pear and plum, respectively. Whereas, the DPPH scavenging activity of herb extracts was found to be IC50-8.18, 19.21 and 25.07 and#956;l/ml and for FRAP activity the values were IC50- 8.86, 27.33 and 60.03 and#956;M/ml Fe (II) equivalents. The IC50 value of nitric oxide scavenging activity was 20.87, 70.12 and 45.74 and#956;l/ml for arjuna, zinger and mint, respectively. The present investigation revealed the significant correlation between total phenolic and flavonoid contents with antioxidant activities of fruit as well as different herb extracts. Pear: Plum blended fruit beverages viz. RTS, squash and jam were prepared and optimized using different combinations and concentrations of pear juice and plum pulp. These combinations and concentrations were adjusted to the best by the panelists, due to its acceptable sugar/acid blend and higher color, flavor, taste, appearance, mouth feel and overall sensory acceptability scores. Optimized functional beverages were fortified with micronutrients i.e. zinc acetate and calcium phosphate dibasic at different levels. The results showed that the incorporation of zinc acetate (20 ppm) and calcium phosphate dibasic (300 ppm) levels into the functional RTS had not affected the sensory properties, when compared with the control. Similarly, the incorporation of zinc acetate (22.5 newlineix newlineppm) and calcium phosphate dibasic (600 ppm) levels into the functional squash and zinc acetate (25 ppm) and calcium phosphate dibasic (1200 ppm) levels into the functional jam had not affected the sensory properties, when compared with the their respective controls. Biosensor analysis of zinc acetate and calcium phosphate dibasic fortified food products using cyclic voltammetric and differential pulse voltammetric analysis revealed the same pattern. As the concentrations of zinc acetate and calcium phosphate dibasic increased in RTS, a decrease in current (Ip) was observed for different concentrations. Similarly, FTIR study revealed that the added zinc and calcium were attached to the reactive sites of functional product components and reduced the transmittance. Determination of levels of herb extracts incorporated in functional fruit products was also investigated. It was observed that the addition of herb extracts had improved the nutritional quality of the fortified functional RTS, squash and jam, as evident from its higher total phenolic and flavonoid content. The ethanolic extract of fruits, herbs and their products (RTS, squash and jam) were analyzed using LC-MS studies and showed the presence of different bioactive compounds. This was the first observation, which provides the insight towards the tremendous potential of underutilized pear and plum from the indigenous Himalayan region of Himachal Pradesh for the development of value added functional food products, with high amount of antioxidants and health endorsing aspects. Keywords: Pyrus pyrifolia, Prunus domestica, Biosensor, LC-MS analysis, FTIR, Antioxidants. newline