Characterization of Malaysian sweet potato ‘Anggun 1’ variety at different storage temperatures and processing conditions
After harvest, the quality of sweet potato is reduced due to loss of physical appearances and biochemical properties. In order to maintain sweet potato quality during storage, sweet potato (Anggun 1) needs to be stored at suitable postharvest storage condition. Thus, the first objective was under...
Saved in:
| Main Author: | |
|---|---|
| Format: | Thesis |
| Language: | English |
| Published: |
2021
|
| Subjects: | |
| Online Access: | http://psasir.upm.edu.my/id/eprint/104117/1/NURFARHANA%20BINTI%20SHAARI%20-%20IR.pdf |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| Summary: | After harvest, the quality of sweet potato is reduced due to loss of physical
appearances and biochemical properties. In order to maintain sweet potato
quality during storage, sweet potato (Anggun 1) needs to be stored at suitable
postharvest storage condition. Thus, the first objective was undertaken to
determine the potential postharvest storage condition that would extend the
physical and chemical, phytochemical and mechanical properties of Anggun 1.
A total 350 samples of Anggun 1 were obtained and stored at two different
storage temperatures (10⁰C and 27⁰C) for a period of 6 weeks. After every 1
week of storage, respective samples were taken out and were measured the
physical and chemical (moisture, dry matter, weight loss, shrinkage, dry matter,
carbohydrate and starch), phytochemical (total phenolic, total flavonoid and
anthocyanin content) and mechanical (penetration and compression test)
properties. Results revealed that storage at 10⁰C could preserve more physical
and chemical properties of Anggun 1 than at 27⁰C. The slower degradations of
phytochemical properties were observed during storage at 10⁰C. Storage at
10⁰C also could better retain the mechanical properties of Anggun 1 than at
27⁰C. Therefore, the most suitable storage condition for Anggun 1 is at 10⁰C
because at this condition the physical and chemical, phytochemical and
mechanical properties were more stable than at 27⁰C for 6 weeks storage.
An understanding of kinetic modeling is important to the food industry in order
to minimize losses of quality in food products during storage. It can be
achieved through the development of mathematical models to predict the
behavior of food quality changes. Therefore, the second objective was to
determine the kinetic models (zero, first and second-order) that describe the
quality changes in Anggun 1 during 6 weeks of storage. All the data from the
first experiment were fitted with zero, first and second-order models using nonlinear
regression performed by statistical method. The selection of the best
fitted model was confirmed by the determination coefficient (R2). Result
revealed that the changes of quality attributes of Anggun 1 during storage can
be described using zero and first-order model. In this objective, the shelf life of
Anggun 1 also predicted based on weight loss analysis. The result showed that
Anggun 1 retained higher shelf life at 10⁰C than at 27⁰C. This indicated that
storage at 10⁰C is more effective storage method for slowing down the damage
of Anggun 1’s quality attributes.
The processing of sweet potato into end products involves peeling which
causes nutritional loss and influences the chemical composition. However,
peeling had an advantage in giving better processing characteristic of sweet
potato products. Thus, the third objective was done to select the best condition
of Anggun 1 through differentiation characteristics of unpeeled tuber (C1),
peeled tuber (C2) and skin of tuber (C3) on the physical and chemical,
phytochemical properties, mineral and anti-nutrient composition. Anggun 1 was
characterized into three different conditions (C1, C2 and C3) in terms of tuber
and flour. Result showed that peeling caused significant loss of physical and
chemical (moisture content, dry matter, fiber, carbohydrate and amylose),
phytochemical (total phenolic content and carotenoid), mineral (calcium) and
anti-nutrient (phytate, tannin and trypsin inhibitor activity) in Anggun 1’s tuber
and flour. It is concluded that the peeling process was responsible for causing
the loss of physical and chemical, phytochemical, mineral and anti-nutrient
composition of Anggun 1. It also can be observed that C1 for tuber and flour of
Anggun 1 had higher dry matter, carbohydrate, amylose, total phenolic,
carotenoid, phytate, tannin and trypsin inhibitor activity than other conditions.
Therefore, it is suggested that C1 of Anggun 1’s tuber and flour is the best
condition in improving the quality of sweet potato because it has been proven
to reduce the loss of physical and chemical, phytochemical properties, mineral
and anti-nutrient composition. |
|---|