| Author | Karki, Dhan Bahadur |
| Call Number | AIT Thesis no. AE-94-12 |
| Subject(s) | Irradiated fruit
|
| Note | A thesis submitted in partial fulfillment of the requirements for the Degree of Master of Engineering, School of Environment, Resources and Development |
| Publisher | Asian Institute of Technology |
| Series Statement | Thesis ; no. AE-94-12 |
| Abstract | Semi-dried mango containing 30 % moisture (w.b.) was prepared by blanching mango
halves for 3 min in saturated steam, osmosing them for 1 hr in 60 °Bx followed by hot air
drying at 66±1 °C. The product was packaged in low density polyethylene and irradiated at
minimum doses of 0, 2, 4, 6, and 8 kGy using a Cobalt-60 of 215595.564 Ci source strength
and stored at 14 °C, 90 % R.H and 30 °C, 80 % R.H conditions. The effects of irradiation and
storage conditions on chemical, microbiological, and sensory quality of the product were
studied.
The average acidity, total sugar, reducing sugar, total carotenes, and yeasts-molds count
of the product were determined to be 2.05 % (w.b.), 44.93 % (w.b.), 13.29 % (w.b.), 2.98
mg/100 g dry matter, and 516 colony forming units per gram (cfu/g) respectively. Results
indicated that irradiation had no significant effects (p>0.05) on acidity, total sugar, reducing
sugar, total carotenes, and sensory quality of the product at all the dose levels studied.
An irradiation dose of 2 kGy was sufficient to prevent the growth of microorganisms
on the product, but a dose as high as 8 kGy failed to reduce the viable yeasts-molds count to
neutrality. Yeasts were found to be more radiation resistant than molds.
Storage temperature had a profound effect on the shelf life of the product. The color
and smell of both the control and irradiated samples deteriorated sharply and became
unacceptable after one month of storage at 30 °C. Irradiated samples stored at 14 °C were
organoleptically satisfactory after 75 days of storage whereas growth of microorganisms were
observed on some of the control samples after 2 months of storage. |
| Year | 1994 |
| Corresponding Series Added Entry | Asian Institute of Technology. Thesis ; no. AE-94-12 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Other Field of Studies (No Department) |
| Academic Program/FoS | Agricultural and Food Engineering (AE) |
| Chairperson(s) | Athapol Noomhorm |
| Examination Committee(s) | Jindal, Vinod K.;Sarath G. Ilangantileke;
Vincent, Jean-Claude |
| Scholarship Donor(s) | German Government |
| Degree | Thesis (M.Sc.) - Asian Institute of Technology |