Assessing the sensorial attributes and phytochemical properties of clingstone peach cultivars: the effect of processing on bioactive composition

Peach (Prunus persica) is considered as a classic fruit for the consumer either as fresh or as processed. Having significant impact on human nutrition, peach is the second most important temperate fruit crop worldwide in terms of production volumes. Peach canning is one of the most popular of all processed fruit, with Greece being the leading country in clingstone peach production and exports of canned peaches at international level. Notably and despite its economic importance, information on bioactive profile analysis of widely grown cultivars and changes induced after canning process is very limited. Thus, in the current project, bioactive compounds including carotenoids and phenolic compounds will be determined in fresh and canned tissue; aiming at the evaluation of the impact level of processing on the composition of bioactive compounds in peach fruit, with special reference to carotenoid content. Towards this aim, peach fruit of eight commercially important clingstone cultivars were harvested according to their maturity stage and size with scalar ripening (spanning from beginning of July to mid of September), and were subsequently processed. Current result indicate great differences among cultivars, highlighting the genotype effect. We have further developed a novel protocol to precisely determine textural properties of canned fruits jointly with Prof. Athina Lazaridou (Aristotle University of Thessaloniki).

The physiological disorder of purple spot in loquat fruit: a physiological, technological and molecular approach

Loquat (Eriobotrya japonica Lindl) market potential is severely affected by purple spot, a pre-harvest physiological disorder, evident as skin discoloration with depressed purple surface. Despite its economic impact, this phenomenon is still poorly investigated and, to our knowledge, this is the first attempt to investigate the molecular mechanism underlying such symptoms. The intensity and severity of purple spot in three loquat cultivars (‘Morphitiki’, ‘Karantoki’ and ‘Obusa’), showing different susceptibility to the disorder, was initially monitored over a period of four months. At commercial maturity stage, harvested fruit were grouped into five distinct categories based on the severity incidence of purple spot. ‘Obusa’ fruits showed the highest incidence of affected fruit, while those harvested from ‘Morphitiki’ did not show any purple spot symptoms. Total soluble sugars, sucrose, glucose and fructose content were measured and key genes implicated in the sucrose pathway [such as (cell wall, cytoplasmic and vascular invertases), sucrose synthase and sucrose phosphate synthase] and in the chlorogenic pathway and oxidation process (such as polyphenol oxidase, phenylalanine ammonia lyase, p-coumarate 3-hydroxylase) were identified.

Application of agricultural biostimulants as a novel sustainable practice to enhance production volumes and qualitative attributes of raspberry fruit

Cultivation of soft fruits like strawberries, blackberries, blueberries and raspberries is receiving accumulating interest and an exponential worldwide demand over the last years, mainly due to their proven health-promoting properties. The latter are considered as added value products but its cultivation in Cyprus is restricted to few hectares, mainly due to lack of the necessary expertise. The aim of the current project is to test the efficacy of agricultural biostimulants (ABs) and its potential to be commercially applied in a sustainable production system, such as Integrated Crop Management (IPM) or an Organic Certified Program, for the production of added value raspberry fruits. These compounds, also mentioned as priming agents (PAs) are generally recognized as safe since they do not leave any harmful residues on fruits and are abundant in natural environments. Furthermore, they have been shown to trigger crop protection mechanisms, against biotic and abiotic stress factors in an array of agricultural commodities. However, there is a lack of scientific evidence regarding their efficacy in raspberry plants. The current project is tightly aligned the 2014-2020 Smart Specialisation Strategy for Cyprus (S3Cy) that identified the agricultural sector as a priority area with high but unexplored potentials. The expected outcomes will be for the benefit of the competitiveness of the Host Organization. The main deliverable of this project will include the development of a publicly accessible recommended management production protocol to enhance production volumes of raspberry plants. Through this approach, our ultimate goal is to disseminate the new knowledge to farmers and agronomists who wish acquire expertise in soft fruit production systems in order to develop a critical mass at National level and address the accumulating needs of the local consumers that are currently fulfilled through imports. The current project is scientifically supported by CUT Fruit Sciences/Postharvest Group and CUT Plant Stress Physiology Group.

Principal Investigator (PI)

The general objectives of this project aimed at the evaluation of quality attributes, phytochemical profile, antioxidant potency and overall postharvest performance of indigenous/traditional apple cultivars, grown in Cyprus, namely ‘Kathista’ and ‘Lortiko’, using ‘Gala’ as reference cultivar. Such traditional cultivars are highly appreciated by the consumers, yet their postharvest performance and phytochemical content were largely unknown. Total phenolic content was dependent on cultivar and length of cold storage, while hydroxycinnamic acids were always at higher levels compared to total flavonols. Quality attributes and polyphenolic content of the traditional apple cultivars were comparable with ‘Gala’ at harvest; thus they can be considered a good source of nutraceuticals as summer apple cultivars. However, extended cold storage deteriorated fruit performance and antioxidant capacity, particularly in ‘Lortiko’ fruit. To this extent, a database for qualitative attributes, nutritional value and antioxidant potential of these cultivars was built. This work resulted in one publication in refereed journal, while a significant number of dissemination activities were carried out, including the development of a website (www.cut.ac.cy/apple) and a well-attended seminar.

The main aim of such internal (CUT) grants is to assist new academic staff to establish their own research program. This grant was particularly important for initiating my research activity at CUT in a way it allowed me to recruit an experienced post-doctoral research associate and to cover the travel cost and cost of living of a professor from Argentina, who spent one month working in our CUT facilities. These cooperations have led to the establishment of a number of experimental protocols that have already been applied in research projects, and the research findings (exclusively carried out at CUT) have been disseminated in the form of three publications in refereed journals. Overall, this grant was particularly important to strengthen the interdisciplinary research with academic groups from other countries, as well as to explore the innovation potential of new approaches undertaken in the area of Postharvest Physiology and Technology of fruit crops. Research findings of this project have been disseminated in the form of 7 publications in refereed journals.

Partner

The objective of this project was to develop a set of postharvest ozone treatments in order to control horticultural products’ quality attributes, in terms of pathogen susceptibility, chemical residues and antioxidant-related compounds. In addition, this work aimed to provide insights into the ozone’s mode of action by analysing gene and protein expression changes in response to ozone treatments. The main outputs of the project was: (1) the development of specific ozone treatments/technology in the horticultural industry for effective fruit preservation, (2) the improvement in the quality and safety of fresh fruits and vegetables, and (3) the molecular view of the underlying mechanisms involved in ozone’s postharvest action. My involvement in the project resulted in two publications in refereed journals, dealing with the efficacy of ozone in kiwifruit postharvest performance.

Considering the economic importance of peach, and also the fact that around 70 new peach cultivars are launched on a yearly basis worldwide, the selection of the most appropriate peach cultivars is of prime importance. Initially, the most widely grown and new introduced peach cultivars was evaluated for their quality attributes and phytochemical properties at harvest and during maintenance at room temperature. Based on these data, a set of 4 cultivars with diverse phytochemical profiles were further evaluated for their postharvest performance and antioxidant profiles after short or prolonged cold storage. In addition, a large scale transcriptomic analysis for a given cultivar and specific storage treatments was carried out. Throughout this approach we identified genes differentially regulated during various storage treatments and to correlate them with quality traits, most promptly those that govern the antioxidant properties and the overall phytochemical profile of peach fruit. This work resulted in two publications in refereed journals and defense of three oral presentations in International Conferences.

A demonstration project called “ORGANIKO LIFE+” was envisioned to provide the field-based evidence that promote Organic Farming (OF) and its products as an important means of mitigating and adapting to climate change in Cyprus; the Italian partner (KC) will provide to the Cypriot team their long-standing experience in LIFE+ climate mitigation projects in Italy and the demands and challenges of the field at the European Commission level. Cyprus is a low-performing country in the organic sector. Among the main objectives of the project were to: (1) develop a strategic national plan of mitigating climate change in agriculture and demonstrate the comparative performance of organic production using a series of climate mitigation indicators in the field, (2) demonstrate comparative advantages of selected organic products in decreasing the body burden of organophosphate pesticides in children, (3) tailor organic farming protocols of major importance for Cyprus agriculture to the local farm(er) characteristics and (4) evaluate the current situation in Cyprus (before and during project implementation) regarding technical stakeholders’ bottlenecks and consumer perceptions. My involvement dealt with the determination of qualitative properties of organically-grown apples compared to conventional ones, as well as the efficient transfer of the results.

The project implements conservation and demonstration actions that highlights the importance of two historical High Nature Value Farmlands (HNVFs) in Cyprus: the traditional vineyard agroecosystem and the carob agrosilvopastoral system. Among main project objectives is to support and promote sustainable agricultural practices that enhance ecosystem services and conserve biodiversity in HNVF, identify strengths and weaknesses of current agricultural management practices with respect to biodiversity conservation, build a knowledge base for vineyard and carob grove HNVF, in Cyprus and encourage stakeholder involvement and increase public awareness regarding HNVF issues through active participatory learning. My contribution involved the defence of two oral presentations about current trends in carob cultivation (extension events); I have also acted as co-author in a manual (72 pages) regarding sustainable agriculture practices in carob groves.

Valorization of the reference indigenous grape cultivar ‘Xynisteri’ under variable vineyard conditions through sensorial analyses and aromatic characterization

Cyprus is one of the very few phyloxera-free areas of the world that cultivates vines in their own roots. Almost ¾ of the total cultivated area uses indigenous cultivars, mainly 'Mavro' and 'Xynisteri' cultivars. The latter is considered as a reference cultivar, used for the production of white wines (light-yellow in colour, balanced, with moderate alcohol and a delicate floral taste), as well as for the production of ‘Commandaria’, a Protected Designation of Origin (PDO) premium dessert wine. Notably, ‘Xynisteri’ is suitable for extreme weather conditions such as drought and hot climate, thus rendering it is an ideal cultivar for marginal soils and adverse climatic conditions. ‘Xynisteri’ is characterized as a very vigorous cultivar, well-adapted in non-irrigated soils and at high altitudes. Under such conditions, wines with distinct aromatic character can be produced, including additionally the potential of aging. Although ‘Xynisteri’ cultivation is of immense significance for the local economy and many wineries cultivate it, it is poorly characterized. Vasiliko Oinopoieio Kyperoundas is a leading company in the field of viticulture and oenology, located in the mountainous area of Cyprus (1200 m) and ‘Xynisteri’ accounts for 50% of its total wine production. The aim of the current project is to valorize the potential of ‘Xynisteri’ under variable vineyard practices through the determination of quality attributes and oenological properties. Special attention will be devoted in the aromatic characterization of ‘Xynisteri’ grapes by means of sensory evaluation and volatile analysis through GC-MS and Electronic nose. At the level of basic research, RNA sequencing for determining expression profiles of genes involved in aroma biosynthetic pathways will be carried out.  Towards the implementation of the aforementioned goals, four Research Units from Academia with highly complementary expertise (vineyard management, determination of qualitative and sensorial attributes, gene expression analyses) will be involved. The expected results of the project will contribute towards the improvement of the quality of the ‘Xynisteri’ wine and release into the market of new added-value products.