Effects Of Osmotic Dehydration And Storage Time On Physicochemical, Microbiological Properties And Sensory Characteristics Of Cocoa Pod Husk Jam

Abstract

Cocoa pod husk (CPH) is the outer layer of the pod (exocarp) being known as underexploited by‐product and not used properly. It contains a low level of lipid and a rich source of nutrients, minerals, antioxidants such as phenolics, and tannin, dietary fibers as well as pectin – a main ingredient which can be applied to the jam industry. Unfortunately, CPH is a rough and thick residue with bitter and acrid taste from high total phenolic content leading to affect consumer’s consumption behavior. Moreover, using high heat to make jam can cause undesirable qualities such as color and aroma; therefore, osmotic dehydration can be used for quality maintenance, nutritional retention during storage, flavor enhancement as well as efficiency in terms of energy. This project focused on investigating the changes of physicochemical and microbiological characteristics of cocoa pod husk jam during osmotic dehydration and storage time (at 4 0C for 2 months), as well as assessing product acceptability. Cocoa pod husk was either osmotically or non-osmotically dehydrated at 40°C in 3 hours before making jam, and finished jam samples were stored in the incubator at 4°C for varying amounts of time (0, 1 and 2 months). Osmotic dehydration had a considerable impact on the physical qualities of the CPH mixture, including the total soluble solid and water activity (higher TSS and lower water activity). TSS values were still greater in treated jam samples compared to untreated ones, but other factors, such as moisture content, ash content, and color attributes, had significant influences as well (higher ash content, color values and lower moisture content); however, pH, moisture and color values gradually decreased throughout storage duration in this study. In terms of chemical qualities, osmotic dehydration preserved more nutritional levels in protein and TPC of cocoa pod husk jam but they were lost at different storage times. Nevertheless, crude fiber of jam samples was just lost after jam manufacture, it kept unchanged after storing. Both treated and untreated jam samples had appropriate levels of microorganisms for consumption during storage at 40C. Sensory qualities did influence by osmotic dehydration (panelists preferred osmotic dehydration jam samples over non-osmotic dehydration ones) and after 2 month storage, their choices did not change. Thus, osmotic dehydration was the most effective approach for reducing nutrient loss, extending the shelf life, and improving the sensory quality of cocoa pod husk jam. After 2 months of storage at 40C, although there were some alterations in the jam samples, its qualities were in adequate assessment for consumers.