Effects of plant density and fertilizer formula on physicochemical and sensorial characteristics of pasteurized juice from Perolera sugarloaf pineapples grown in the long rainy season

Abstract

High quality products can be produced only from high quality raw materials. The best agricultural practices that lead to pineapple fruits of desirable quality were investigated in the present study, focusing on the quality of the derived pasteurized juices. Physicochemical characteristics and sensory quality of the juices were determined in relation to planting density and fertilizer formulation, namely the K2O:N ratio. Three planting densities (D1: 54 400 plants/ha, D2: 66 600 plants/ha and D3: 74 000 plants/ha) and three K2O:N ratios (E1: 0.37, E2: 1.0 and E3: 2.0) were applied in nine treatments. Fruits were harvested and processed into juice following a standardized process. Pasteurization was applied after bottling, at 85 °C for 15 min. Juices’ pH, total soluble solids, color and density were determined. Sensory profiles were established by 14 trained panelists using the Quantitative Descriptive Analysis (QDA) method and their acceptability was evaluated. Results showed that the lower the planting density, the less yellow the pasteurized juice. The K2O:N ratio increased the juices’ degrees Brix from 13.1 to 14.4 and the yellow color. Pineapple fruits produced at a density of 54 400 plants/ha with a K2O:N ratio of 1.0 (D1E2) yielded the most sweet, least acid and pasteurized juice most liked by consumers, supported by high values of degree Brix and pH. Juices with the closest similar sensory appreciation were those obtained from treatments D3E2 and D3E1. Pineapple farmers that furnish their products to juice processors should adopt one of the best combinations stated in this study.