Research on prolonging the marketing period of dried and ready-to-eat type figs (Ficus carica)

26th International Horticultural Congress -- AUG 11-17, 2002 -- TORONTO, CANADAWOS: 000189407100055Commercial fig drying is an important agricultural activity in the western part of Turkey. The region by itself provides 60 % of the world trade. The research was carried out in 2000 and 2001 on intermediate moisture sun-dried figs and rehydrated ready-to-eat type of fig fruit. After being sun-dried, figs were put in gas tight polyethylene packages. Some of the packages were heat-sealed without any application as control; some of them were applied with vacuum whereas others were filled with N-2 or CO2 (20 % CO2+ 80 % N-2) after vacuum application. Another variable was cold storage (4+/-1 degreesC, 55-65%RH) versus ambient temperature conditions (ca 15 degreesC and 55 % RH). Samples were derived at 45 days intervals and quality parameters as firmness (kg), weight loss (%), dry weight (%), moisture content (%), water activity (a(w)), color (L, a, b and a/b), total soluble solids (%) and sugar exudation (%) were analyzed. Dried figs were also rehydrated to exceed 30% or higher moisture content to prepare commercial packs for consumption as ready to eat. After rehydration, figs were put in gas tight polyethylene packages. Various package atmospheric compositions as air, N-2 or CO2 (20 % CO2+ 80 % N-2) were tested. Besides the quality parameters determined for intermediate moisture sun-dried figs, microbiological and sensory analysis such as taste, aroma and texture were performed at monthly intervals. The results proved that darkening of the fruit color and sugaring were the major quality attributes affected by the storage conditions. Vacuum applications are not recommended due to the exudation of the fruit juice.Canadian Soc Hort Sci, Int Soc Hort Sci, Univ Guelp

Effect of yearly conditions and management practices on ochratoxin A production in Sultana Seedless vineyards

Sun drying of seedless grapes (Vitis vinifera cv. Sultanina) is widely practised in the western Aegean Region providing Turkey with a significant share in the world trade of sultanas. Research was initiated in 1998 to determine the incidence of ochratoxin A (OTA), to identify the major factors resulting in contamination and to develop techniques to reduce or prevent contamination. This paper assesses OTA formation in five experimental vineyards located in Manisa province of Turkey between 1998 and 2003. The cultural practices recorded were tillage (type and timing), fertilisation, plant protection, irrigation, trellising, pruning, GA(3) application, harvest maturity and date, and drying practices (type of drying yard, dipping into alkaline solution, length of drying period). In the experimental vineyards, no OTA was found at veraison. OTA levels in grapes harvested at fresh maturity ranged betwee

Ochratoxin A in sultanas from Turkey I: Survey of unprocessed sultanas from vineyards and packing-houses

WOS: 000233851900010PubMed ID: 16332638A method for the determination of ochratoxin A ( OTA) in sultanas from Turkey using extraction with a sodium bicarbonate solution ( 2% NaHCO3) followed by immunoaffinity clean-up and liquid chromatography with fluorescence detection was used to assess the frequency of occurrence and level of OTA. In-house validation was carried out with spiked samples at levels of 0.15, 1.5, 5.0 and 10 mu g kg(-1) and average recoveries were 91, 93, 87 and 89%, respectively. The limits of detection and limit of quantification in Turkish sultanas were 0.026 and 0.09 mu g kg(-1), respectively. A survey for the presence of OTA was carried out on 264 unprocessed sultana samples during the production seasons between 1998 and 2000 collected annually from vineyards and from packing-houses. The analyses of unprocessed sultanas showed that 32.2% of the total number of samples contained no detectable OTA, whereas 9.8% of sultana samples had OTA concentrations above 10 mu g kg(-1), and the remaining 58% had levels within the range 0.026-10 mu g kg(-1). There were big differences in median concentrations between years. Considering the year of production, it appears that sultanas produced in 1998 and 2000 showed the lowest incidence of OTA contamination ( median < 0.02 mu g kg(-1)), whereas 2002 showed the highest incidence ( median 4.3 mu g kg(-1)1). The overall mean OTA concentration was calculated as 3.4 mu g kg(-1), and the overall median as 0.9 mu g kg(-1). Among the samples analysed, the highest detected level of OTA was 54 mu g kg(-1)

Project to phase-out methyl bromide in the dried fig sector in Turkey

26th International Horticultural Congress -- AUG 11-17, 2002 -- TORONTO, CANADAWOS: 000189407100007Turkey is one of the major dried fruit and nut producing countries. Methyl bromide (MeBr) is the common fumigant to control storage pests that infest during drying and storage. Compared with other dried fruits and nuts, storage pest infestation threatens dried fig production the most. MBr is regarded as a major anthropogenic compound that depletes the ozone layer. Furthermore, MeBr is a toxic gas and can pose risk to human health if over-exposure or accidents occur. The Montreal Protocol and the phase-out of methyl bromide have increased the urgency to search for new technologies. This project will lead to the phase-out of MBr as a stored product treatment in the Turkish dried fig sector by evaluating the economic and technical feasibility of two alternative technologies: 1) CO2 at elevated temperatures and/or CO2 in combination with pressure, and 2) magnesium phosphide in combination with heat in gas tight chambers. In addition, the project will include activities for ensuring a proper technology transfer, through a training programme and dissemination of information directed at actual MeBr users in the Turkish dried fig industry. Until today, field surveys are carried out to evaluate the importance of target species. Dried fig fruits are treated with magnesium phosphide and CO2 at various concentrations and at different temperatures. Quality parameters such as total soluble solids (%), titratable acidity (%), pH, dry matter (%), water activity (WA), colour (L, a and b values by Minolta chromometer) and sugaring (%) are assessed in treated and non-treated samples.Canadian Soc Hort Sci, Int Soc Hort Sci, Univ Guelp