Application of ozone and bioagents for extension of storage life of strawberry
Loading...
Date
2017
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
DIVISION OF FOOD SCIENCE & POSTHARVEST TECHNOLOGY ICAR- INDIAN AGRICULTURAL RESEARCH INSTITUTE NEW DELHI
Abstract
The present study envisages the influence of ozone and bioagents on strawberry fruits
with an objective of maintaining postharvest quality and extending its storage life so
as to make it available for longer period during the season. For this, two experiments
were conducted on strawberry cv. ‘Winter Dawn’. In the first experiment, fruits were
harvested at 3/4th colour development and subjected to application of 0.1 ppm ozone
for various time period (1, 2, 3, 4 minutes) to standardise the optimum ozonation
time. Water washed strawberries were used as control. In another experiment,
strawberry cv. ‘Winter Dawn’ fruits were treated with three different bioagents,
namely Bacillus subtilis, Pseudomonas fluorescens and Debaryomyces hansenii at a
concentration of 107
cfu/ml. However for this experiment, two controls were taken,
first in which fruits were not washed with water after treatment and in another, where
the fruits were washed with water. For both the experiments, the strawberries were air
dried and then packed in plastic punnets. The fruits of experiment-I were stored at two
different storage conditions, i.e., at low temperature (2±1°C & 90-95% RH) and
ambient temperature conditions (25±2°C & 45-50 % RH). For bioagent study, fruits
were also stored at two conditions i.e., low temperature (5±1°C & 90% RH) and at
ambient conditions (25±2° C & 90 % RH). Then, the treated strawberries were
analysed for observing changes in the physical, biochemical and microbial
parameters. In the first experiment, 0.1 ppm aqueous ozone applied for 2 minutes
gave the best results, which significantly maintained the strawberry quality up to 14
days at low temperature (2±1°C & 90-93 % RH) and 3 days at ambient storage
condition (25±2°C & 45-50 % RH). In the experiment 2, Debaryomyces hansenii
exhibited the best results which lasted for 10 days at low temperature and 3 days at
ambient storage condition. Control (water dipped) fruits showed maximum changes in
the quality attributes as compared to the fruits which were not water washed and other
treatments. The firmness losses, fruit decay, weight loss and biochemical changes
were significantly low at low temperature storage conditions (2 ± 1°C). Colour
changes were retarded as evidenced by the slow decrease in the chroma and hue angle
in these optimized treatments. In general, treated samples showed a higher retention
of biochemical parameters such as titratable acidity, TSS, ascorbic acid, anthocyanin,
total antioxidant activity and total phenols in comparison to untreated fruits. Hence, it
can be concluded that both aqueous ozone (0.1 ppm) dip for 2 min and application of
Debaryomyces hansenii at 107
cfu/ml, can be recommended for extending storage life
of ‘Winter Dawn’ strawberry fruits.
Description
t9682
Keywords
null