Experimental study on storage stability and rheological property of coconut water beverage

Abstract: During the storage period, some kind of quality problems exist in a coconut water beverage such as precipitation and suspension, which could affect the quality and stability of the product. This paper attempted to analyze the influence of storage temperature and storage time on the physical and chemical indicators of a homemade coconut water beverage, commercial coconut water beverage, and natural coconut water, as well as the rheological property of each coconut water beverage was researched in detail. In this paper, the homemade coconut water beverage, commercial coconut water beverage, and natural coconut water were used as material and their storage stability were studied in detail, which involved storage at 4℃ refrigerated, 20℃ room temperature, and 37℃ condition along with t variation of nutrient composition and shelf life. The study aimed at revealing the relationship between rheological property and storage stability of the coconut water beverage. The rheological property of each coconut water beverage was measured by rheometer. The results indicated that the components and contents of the physical and chemical indicators were significantly different in those samples, but the solid content, pH value, total acidity, and Vc didn't change significantly at a 4℃ refrigerated storage condition, including a pH value from 4.5±0.01 to 4.48±0.02, solids content from (4.0±0.03)% to (5.0±0.02)%, total acidity from (1.01±0.01) g/L to (0.94±0.01) g/L, the loss of vitamin content was less than (6±0.03)%, the coconut water beverage with better stability, and the total number of bacterial colonies was less than 100 CFU/mL, respectively. Therefore, the quality of coconut water beverage presented good stability at 4℃ refrigerated for 50 days. It was found that the rheological property of coconut water beverage was a typical pseudo-plastic fluid. While the shear rate of 200 s-1 along with a temperature rise from 4℃ to 40℃, the viscosity increased from (0.018±0.003) mPa·s to (0.030±0.001) mPa·s, the system viscosity along with the change of temperature is more moderate, and the effect of temperature on a coconut water beverage system was not obvious, so the storage stability of a coconut water beverage kept well at 4℃. The coconut water beverage was rich in nutrition, and was a product with potential in the beverage market, and it has attracted increasing consumer concern. The storage stability was a key indicator in control of coconut water beverage quality. This would solve the precipitation, taste. And storage issues of coconut water beverage, providing a more reliable theoretical basis for developing the research of quality and nutrition in coconut water beverage and the construction of a quality evaluation system. It was believed that we would produce coconut water beverage with the original flavor, good quality, more freshness and more stability in the future.