Economic analysis of an isolated product obtained from muscadine grape pomace

Abstract

The grape (Vitis vinifera) industry has long been a leader in the utilization of edible by-products to increase the revenue of the industry with products such as grape seed extract, dried pomace, and pigment extracts. However, the muscadine grape (Vitis rotundifolia) industry in the southeastern United States has lagged in the development of secondary products from wine and juice manufacture due to economic and processing limitations associated with this grape. Processing of pomaces rich in polyphenolics, such as muscadine grapes, can lead to an increase in economic value per ton of fruit and the decrease of waste material generated. Therefore, the profitability of two drying technologies (spray drying and vacuum concentration) was assessed as means to extract and concentrate polyphenolics from muscadine grape pomace. An economic analysis was conducted based on break-even point analysis, sensitivity analysis, and return on investment estimation. Assumptions were required to complete the analysis. Using initial production conditions (124 kg of extract at $140/kg, and 11,309 kg of dried skins at $3.00/kg), the profit generated from spray drying was higher than vacuum concentration. In addition, return of investment was 10% higher in spray drying (22.2%) compared with vacuum concentration (12.3%), which barely covered the net present value of the operation. Although spray drying proved to be a less expensive technology (with the actual characteristics and proper assumptions), the vacuum evaporator used for this situation had three times the capacity of the spray dryer, thus only vacuum concentration would support a potential growth in extract production if the volume processed was to be increased significantly. Sensitivity analysis illustrated that both technologies obtained positive results with initial production conditions with a 40% increase in production and prices. This study also illustrated various assumptions that could be changed to recalculate and readjust investment and costs of any processor.