Projects / Programmes
Modulation of fruit polyphenolic profile by sustainable postharvest physical treatments
| Code |
Science |
Field |
Subfield |
| 1.02.07 |
Natural sciences and mathematics |
Physics |
Biophysics |
| 4.03.07 |
Biotechnical sciences |
Plant production |
Technology of vegetal origin food |
| Code |
Science |
Field |
| 1.03 |
Natural Sciences |
Physical sciences |
| 4.01 |
Agricultural and Veterinary Sciences |
Agriculture, Forestry and Fisheries |
postharvest treatments of fruit, water dipping and LED irradiation, characterization of fruit surfaces, bacterial adhesion mechanism on fruit surfaces
Researchers (17)
Organisations (4)
Abstract
Fruit is considered inevitable part of human nutrition due to the content of important constituents like antioxidants, vitamins, minerals and dietary fibre. On the other hand, fruit is vulnerable to physiological and microbiological deterioration and consequently of short shelf-life. Recently, modern food systems have been faced with a challenge to accelerate the shift towards sustainable development and production. During growth, fruit needs adequate temperature and sunlight, inadequate quantity might provoke stress that result in reduced yields and poorer quality. According to our preliminary experiments, post-harvest application of appropriate light irradiation of fruit causes a moderate stress, which renders fruit more resistant to physiological and microbiological diseases. The first objective of the project is to study the fruit physiological response on post-harvest treatments: irradiation of apples with light emitting diodes (LED) or application of edible coatings. Fruit surface will be modified with edible coatings based on polyelectrolyte multilayers in order to evaluate its preservation effect. First the impact of various experimental parameters on the formation of polyelectrolyte multilayers will be studied, and later on, investigation of antimicrobial properties of polyelectrolyte multilayer coatings on fruit surfaces will be performed. LED treatment will include wavelengths from 445 nm. These treatments will modify fruit physiology in terms of maintaining fruit quality and reducing physiological. Post-harvest LED treatments affect phenolic compounds in fruit. Therefore, the second objective is to consider phenolic profile of fruit by means of LCMSMS and 1H NMR spectroscopy as influenced by treatments. Among phenols, flavonoids are known to influence color, astringency and antioxidant properties and thus we will determine color after post-harvest treatments. The third objective is applying Atomic force microscopy (AFM) for the characterization of the fruit surface topography. Surface hydrophobicity will be determined by contact angle measurements. The secondary metabolites in fruit also determine the fruit susceptibility toward microorganisms. Penicillium expansum attachment will be elucidated using stereological methods based on Scanning Electron Microscopy (SEM) images. P. expansum attachment rate on the fruit surface will be assessed by using automatic image segmentation techniques. Moulds play a key role in food safety, their presence might result in mycotoxins production. Patulin is one of the most common mycotoxins in apples. Here the forth objective is to quantify P. expansum growth on apple and patulin with High-performance liquid chromatography (HPLC) in apples prior and after post–harvest treatments. We expect that phenolic profile of fruit peel will be in negative correlation with growrh of P.expansum. The fifth objective is determination of proteomic response of apple peel inoculated with P. expansum after irradiation with blue LED light. Finally, we expect to choose optimal parameters for post-harvest treatments in order to modulate synthesis of fruit phenolic compounds. Application of edible coating will affect fruit surface, fruit physiological activity, P. expansum attachment, and spoilage. Therefore, this fruit will have optimal nutritional value and quality that will maintain human health. Both postharvest treatments are regarded as sustainable.
