Use of high pressure technology for the development of novel jam and its quality evaluation during storage

Jam like product was prepared using high pressure (HP) processing technology and was compared with thermally processed one for quality attributes. Strawberry pulp was mixed with pectin (1%) and sugar and packed in low density polyethylene pouches (50 g pack size) and processed at 200, 400 and 600 MPa for 30 min at 50 °C. Ascorbic acid, anthocyanins, phenolics, flavonoids and antioxidant activities were found to be significantly retained to a better extent in HP processed jams as compared to thermally processed one. The CIE L*, a* and b* values decreased significantly with increase in pressure, the decrease being of much lesser extent compared to thermally processed one. Increase in pressure was found to increase the sensory attributes for colour, appearance, flavour, texture and overall acceptability significantly; however, the scores were comparatively lesser than that of thermally processed jam. The sample processed at 600 MPa showed a shelf-life of 3 months on the basis of physico-chemical, sensory and microbial attributes when stored at ambient storage conditions (28 ± 5 °C).