Kentucky State University
Effects of Hot Water and Acidic Electrolyzed Water Treatment on Microbial Load and Quality Characteristics of Pawpaw Fruits
Institution
Kentucky State University
Faculty Advisor/ Mentor
Lingyu Huang; Cecil Butler; Changzheng Wang
Abstract
Pawpaw fruit has a relatively short shelf life, limiting the time for its processing and marketing. Deactivating enzymes involved in maturation and eliminating microbial contamination have the potential to extend the fruit’s shelf life. The objective of this study was to determine the effects of pretreatment with hot water and acidic electrolyzed water on the microbial load and quality characteristic of pawpaw fruits. Pawpaw fruits were harvested from the research orchard of Kentucky State University. Fruits were randomly assigned to receive no pretreatment, pretreatment with heating in water at 60 C for 5 min, rinsing with tap water or acidic electrolyzed water for 2 min. Three fruits from each group were analyzed for weight loss, hardness, pulp color and Brix value on day 1, 7, 10 and 14 after the pretreatment. The fruits were also inspected visually. Microbial load was relatively high at the beginning and became lower during the experiment. Pretreatment with acidic electrolyzed water reduced the microbial load but did not delay the deterioration of the fruit. The hardness of the fruits declined for all groups but was slightly less for the hot water treated group. As time increased, fruits tended to turn dark in skin color and number of sagging spots increased. However, appearance of the hot water treated group remained acceptable up to 14 days, indicating that hot water treatment delayed the maturation process and extended slightly the shelf life of pawpaw fruits.
Effects of Hot Water and Acidic Electrolyzed Water Treatment on Microbial Load and Quality Characteristics of Pawpaw Fruits
Pawpaw fruit has a relatively short shelf life, limiting the time for its processing and marketing. Deactivating enzymes involved in maturation and eliminating microbial contamination have the potential to extend the fruit’s shelf life. The objective of this study was to determine the effects of pretreatment with hot water and acidic electrolyzed water on the microbial load and quality characteristic of pawpaw fruits. Pawpaw fruits were harvested from the research orchard of Kentucky State University. Fruits were randomly assigned to receive no pretreatment, pretreatment with heating in water at 60 C for 5 min, rinsing with tap water or acidic electrolyzed water for 2 min. Three fruits from each group were analyzed for weight loss, hardness, pulp color and Brix value on day 1, 7, 10 and 14 after the pretreatment. The fruits were also inspected visually. Microbial load was relatively high at the beginning and became lower during the experiment. Pretreatment with acidic electrolyzed water reduced the microbial load but did not delay the deterioration of the fruit. The hardness of the fruits declined for all groups but was slightly less for the hot water treated group. As time increased, fruits tended to turn dark in skin color and number of sagging spots increased. However, appearance of the hot water treated group remained acceptable up to 14 days, indicating that hot water treatment delayed the maturation process and extended slightly the shelf life of pawpaw fruits.