Fresh Raspberries Research Articles

A comparison of raspberry freezing-damage during preservation in isochoric and isobaric conditions.

Fruits are perishable, thus it's crucial to have an efficient preservation technique that can increase storage time while keeping physical quality and nutritional attributes in order to avoid wastage. The majority of methods for long-term storage require refrigeration. In this investigation, we assess the viability of isochoric freezing as a different technique of raspberry (Rubus idaeus L.) preservation. Raspberries were subjected to different storage conditions: isochoric freezing at -4°C, conventional isobaric settings at +3°C (refrigerator), -21°C (freezer), and -4°C with a trehalose solution in a plastic bag. The study assessed changes in weight loss, visual appearance, color, hardness, °Brix values, and pH over a seven-day period. Key findings reveal that raspberries subjected to isochoric freezing below the freezing point of water experienced minimal weight loss after seven days. Visual appearance, color, hardness, °Brix values, and pH were comparable to fresh raspberries, indicating minimal alteration. These results suggest that isochoric freezing shows potential as a preservation method that maintains the physical and chemical properties of raspberries similar to fresh fruit. Implementing diverse preservation techniques tailored to raspberries may contribute to environmental sustainability by reducing food wastage and the associated environmental impact.

Comparison of different methodological choices in functional unit selection and results implication when assessing food-packaging environmental impact

As defined by ISO standards 14040 and 14044:2021, Functional Unit (F.U.) is a quantifiable function of a product and is the reference basis for system modelling in environmental assessment. For this reason, F.U. definition is one of the most critical and controversial methodological aspects of LCA methodology. Literature search showed that two different F.U. are indistinctly used for shelf-life inclusion in food packaging LCAs. Inherent F.U., or attribute driven approach, includes shelf-life as an inherent characteristic of packaging solutions. An example would be “the conservation of X grams of packaged food until the end of its shelf-life”, On the other hand, Explicit F.U., or decision driven approach, explicitly requires a target timespan to be fulfilled such as “the conservation of X grams of packaged food over a Y-days timespan”. Still, the two are implemented without actual knowledge of their conceptual differences, resulting in inconsistency among practitioners. This paper aims at clarifying the impact of the two F.U. on comparative food packaging LCAs with the scope of harmonising future methodology for shelf-life inclusion into impact assessment methodology. The case of packaged fresh raspberries was used for this purpose. Three packaging solutions were compared by means of both the Inherent and Explicit functional units. Impact assessment results demonstrated that the two F.U. call for different scopes, modelling as well as providing different outcomes. For Inherent F.U., the overall best packaging solution was the one that successfully balanced food protection with packaging production and disposal impacts. On the contrary, the packaging system that most successfully fulfilled the targeted timespan resulted as the best available choice for the Explicit functional unit. Based on LCA outcomes, it was suggested that an Inherent approach should be used to discriminate packaging solutions based on their attributes and to critically analyse them. On the other hand, Explicit F.U. a packaging system to is best implemented when a predefined time requirement needs to be met. This decision-driven approach compares packaging solutions in respect to their goodness to fulfil a required shelf-life and to guide future eco-design decisions. Nevertheless, hot-spot analysis uniquely showed that food production, with food waste probability, was the most impactful factor, highlighting the relevance of shelf-life inclusion in LCA studies. Eventually, the study provided suggestions on the best use of the two F.U. for food packaging environmental assessment.

Dose-Related Regulatory Effect of Raspberry Polyphenolic Extract on Cecal Microbiota Activity, Lipid Metabolism and Inflammation in Rats Fed a Diet Rich in Saturated Fats.

The amount of berry polyphenols required to exert health-promoting effects seems to be difficult to achieve by fresh fruit ingestion, so polyphenol-rich extracts could be considered a dietary alternative. In the present study, laboratory rats were fed high-fat diets supplemented with 0.1 or 0.3% raspberry polyphenols from pomace, with the former dose reflecting the amount of polyphenols consumed with a glass of fresh raspberries. It was hypothesized that beneficial changes in blood and hepatic tissue related to lipid metabolism would accompany both treatments, but the health-promoting effect would be more noticeable with the higher dose of extract. This hypothesis was confirmed, and the high dose of raspberry polyphenols was better than the low dose extract in terms of decreased epididymal white adipose tissue weight, hepatic triglyceride content, PPARγ and SREBP-1c expression in the liver, and plasma IL-6 concentration, as well as increased acetic acid concentration in the cecal digesta. These effects might be partially associated with the enhanced content of ellagitannin and anthocyanin metabolites found in the blood plasma of rats administered the high dose of the extract. The results showed that this extract could be considered a dietary vehicle to provide an amount of raspberry polyphenols that could promote health.

An analysis on the impacts of cryogenic freezing on raspberry quality

Counter-season supply of horticultural products is of increasing demand. Consumers are demanding annual supply of raspberries, which has historically been challenging due to their seasonal summer supply and characteristically high metabolism resulting in a short shelf life and limited period of availability. However, the development of freezing technologies for increasing the length of storage of raspberries offers an opportunity for continual supply of premium quality raspberries. We investigated berry quality after freezing whole fresh raspberries, comparing conventional freezing methods with a modern cryogenic freezing method over a period of six months. Significant increases in total soluble solids, titratable acidity, hue and chroma were found when raspberries were frozen compared to fresh raspberries. No overall difference in berry quality was observed between freezing methods for any parameter assessed. When assessed at time intervals, total soluble solids, pH, titratable acidity, chroma and hue were consistent between freezing methods for all durations of time frozen. These findings provide decision support for producers and distributors pursuing a novel counter season supply chain.

Efficacy of cold atmospheric plasma for inactivation of viruses on raspberries

In this study, the effectiveness of cold atmospheric plasma (CAP) in inactivating murine norovirus (MNV/human norovirus surrogate) and hepatitis A virus (HAV) on aerosol-inoculated dark red Willamette raspberries was explored. Pulsed positive corona discharge system fed by synthetic air was used for the production of CAP. Raspberries were treated for 1, 3, 5, 7, and 10 min at 25 W. Application of CAP enabled a 4 log10 infectivity reduction in <5 min for MNV and approximately 10 min for HAV (from starting level of 6.91 and 7.84 log10 PFU/mL, respectively). Viral genome copies reduction of 3.18 log10 for MNV and 4.32 for HAV were found from starting level of 5.76 and 6.47 log10 gc/μL, respectively. CAP treatment did not result in significant degradation of fruit color, an important quality attribute. The study demonstrated CAP as an efficient post-harvest decontamination method to reduce viral load in raspberries without significantly affecting its quality parameters. Industrial relevanceDue to the fast-processing paces required in the raspberry industry, it is difficult to assure the complete microbiological safety of this fruit. Cold atmospheric plasma is a practical, environmentally-friendly, non-thermal tool for the effective reduction of microbial pathogens. The model developed in this study demonstrated that CAP treatment of fresh raspberries not only inactivated hazardous enteric viruses in a short time (10 min) but also unaffected fruit color stability. The simplicity of described CAP design and low-cost inputs (air and electricity) enable the commercial application of inexpensive plasma chambers for continuous surface decontamination of large volumes of raspberries without bringing processing to a standstill.

Chitosan and pectin-based films and coatings with active components for application in antimicrobial food packaging

This investigation was aimed to develop films and coatings based on natural biopolymers and active components, with physicochemical and functional properties for application in antimicrobial packaging. Biopolymer films were obtained from emulsions and dispersions by casting method. Coatings were formed by the application of emulsions on existing packaging. Synthesis of emulsions and dispersions were performed by combining biopolymers (chitosan-gelatin, pectin-gelatin) with lemongrass essential oil (LEO), Zn(CH3COO)2·2H2O, or ZnO, as active components. Fourier transform infrared (FTIR) spectra of the films showed that the addition of glycerol contributed to the forming of strong hydrogen bonds between glycerol and chitosan-gelatin or pectin-gelatin composites, facilitating the process of polymer branching, which is substantial for encapsulation. Thermal analyses revealed two characteristic processes occurring at 110 °C (water evaporation) and within 215–235 °C (degradation of polysaccharide and glycerol). Major weight losses were observed at 290 °C (chitosan-gelatin films) and 215 °C (pectin-gelatin films). The chitosan-gelatin films exhibited a lower degree of solubility (31–21%), and better mechanical properties comparing with the pectin-gelatin films. The chitosan-gelatin emulsions and dispersions exhibited a higher antibacterial effect in vitro against E. coli, B. subtilis, and S. aureus. In the case of the pectin-gelatin emulsions, the impact of LEO on the antibacterial activity was evident. The effects of biopolymer coatings on the development of microorganisms on fresh raspberries (Rubus idaeus L.) were performed in vivo during eight days of raspberry storage at refrigerator temperature. The tested coatings extended the shelf life of stored raspberries from four to eight days. The synergistic effect between LEO and ZnO or Zn-Ac was observed both in vivo and in vitro.

Preservation treatment of fresh raspberries by e-beam irradiation

E-beam irradiation was studied as a post-harvest treatment for red raspberries (Rubus idaeus L.). Microbial inactivation (natural microbiota and potential pathogenic bacteria) and bioactive properties (phenolic content, vitamin C content and antioxidant activity and cytotoxicity) of these fruits were evaluated before and after irradiation and during storage of 14 days at 4 °C. A reduction of 2 log CFU/g of mesophilic bacteria and 3 log CFU/g on filamentous fungi, and no detection of foodborne inoculated pathogens (3 log CFU/g) was achieved with an e-beam treatment at 3 kGy and during 7 days of refrigerated storage. Regarding bioactive properties, the results suggested that irradiation could preserve the phenolic content and antioxidant activity of raspberries through 7 days of cold storage, even though a decrease of 80% on ascorbic acid concentration was observed. Furthermore, no in vitro inhibitory effect on human cells lines was observed for the extracts from e-beam-treated raspberries. The overall results suggested that use of e-beam irradiation as post-harvest treatment of raspberries as an emergent, clean and environmental friendly process to extend the shelf-life of this fruit with safety and preservation of bioactivity. Industrial relevanceRed raspberries are known to demonstrate high bioactivity that could be beneficial to human health, but are highly perishable and often associated with foodborne outbreaks, which makes its safety and commercialization a challenge. The use of a terminal control such as irradiation might reduce the burden of disease transmission and extend the quality of fresh red raspberries. The present research indicated that e-beam irradiation can be used as post-harvest treatment of raspberries, guarantying its safety and quality with the add-value of shelf-life extension.

Ranking and multicriteria decision making in optimization of raspberry convective drying processes

AbstractSerbia is one of the leading producers and exporters of raspberry in the world, and considering the short shelf life of raspberry, the processing, storage, and transport are some of the main issues to be addressed.A comparative experiment was conducted in order to find the suitable process parameters for convective drying that may be considered as the alternatives to freeze‐drying, which is a widely used preservation method for raspberry even though it is a costly and energy‐consuming method. Twelve convective drying regimens were applied with a combination of three influencing factors: air temperature (60°C, 70°C, and 80°C), air rate (0.5 and 1.5 m·s−1), and stage of raspberry (fresh and frozen). The final product, a dried raspberry, was assessed for chemical, physical, and mechanical properties and rehydration capacity. Deep ranking analysis by power eigenvectors (DRAPE) and sum of ranking differences (SRD) were used to uncover the differences and similarities between the applied drying methods.SRD showed that convective drying of fresh raspberries proved to be more similar to freeze‐dried raspberries than convective drying of frozen ones. Fresh samples dried at 60 °C air temperature and 1.5 m·s−1 air flow proved to be the most similar to the reference freeze‐drying method. This convective regimen gives samples with the lowest color change, shrinkage, and shape deformation. With the mechanical and chemical properties of these samples being observed, statistical Duncan's test show that there is no significant difference (P &lt; .05) in terms of hardness, shear force resistance, total phenolic, and total flavonoid preservation, compared with freeze‐dried samples. DRAPE gave similar results, but it added the variable importance in ranking as well, and total phenol reduction was defined as the most important variable. These results can help practitioners to develop cheaper and simpler drying methods that would replace the freeze‐drying but keep the same quality of the dried products.

Convective Drying of Fresh and Frozen Raspberries and Change of Their Physical and Nutritive Properties.

Raspberries are one of Serbia’s best-known and most widely exported fruits. Due to market fluctuation, producers are looking for ways to preserve this fresh product. Drying is a widely accepted method for preserving berries, as is the case with freeze-drying. Hence, the aim was to evaluate convective drying as an alternative to freeze-drying due to better accessibility, simplicity, and cost-effectiveness of Polana raspberries and compare it to a freeze-drying. Three factors were in experimental design: air temperature (60, 70, and 80 °C), air velocity (0,5 and 1,5 ms−1), and state of a product (fresh and frozen). Success of drying was evaluated with several quality criteria: shrinkage (change of volume), color change, shape, content of L-ascorbic acid, total phenolic content, flavonoid content, anthocyanin content, and antioxidant activity. A considerable influence of convective drying on color changes was not observed, as ΔE was low for all samples. It was obvious that fresh raspberries had less physical changes than frozen ones. On average, convective drying reduced L–ascorbic acid content by 80.00–99.99%, but less than 60% for other biologically active compounds as compared to fresh raspberries. Convective dried Polana raspberry may be considered as a viable replacement for freeze-dried raspberries.

Extended direct lysis method for virus detection on berries including droplet digital RT-PCR or real time RT-PCR with reduced influence from inhibitors

Detection of viruses on berries is a challenging task, often hampered by the presence of RT-qPCR inhibiting substances from berry juice. A direct extraction method for virus detection (murine norovirus and GA phage) on frozen raspberries was previously published. We expanded (different types of berries and viruses) and improved the method using MobiSpin S400 columns that filter nucleic acids based on size-exclusion chromatography. While no inhibition was detected in filtered RNA, unfiltered RNA needed from 1:2 to more than 1:8 dilution in order to remove inhibition. The modified method gave recoveries of bovine norovirus around 40.8 ± 4.5% (40.0 ± 7.0%), 48.0 ± 26.0% (50.5 ± 7.8%), 28.3 ± 2.6% (45.8 ± 6.6%) from frozen (fresh) raspberries, strawberries and blueberries, respectively. For the same samples, recoveries of hepatitis A virus were 34.0 ± 5.9% (34.0 ± 6.0%), 40.0 ± 13.3% (34.2 ± 10.5%) and 23.0 ± 6.8% (31.5 ± 7.9%). For adenovirus40 (DNA virus), recoveries were 21.2 ± 8.6%, 16.0 ± 3.2% and 5.7 ± 0.2% from fresh raspberries, strawberries and blueberries respectively and column filtration did not add any improved effect. The modified method is effective and timesaving for detection of viral RNA from both fresh and frozen berries. As an emerging detection and direct quantification method, droplet digital RT-PCR was compared to RT-qPCR and was much less influenced by inhibitors when detecting mengovirus in unfiltered RNA from berries. However, for low levels of pure RNA, RT-qPCR showed slightly higher sensitivity and more stable results.

Prevalence of Norovirus in produce sold at retail in the United Kingdom

To acquire data on contamination with Norovirus in berry fruit and salad vegetables in the United Kingdom, one thousand one hundred and fifty two samples of fresh produce sold at retail in the UK were analysed for Norovirus. Of 568 samples of lettuce, 30 (5.3%) were Norovirus-positive. Most (24/30) lettuce samples which tested positive for Norovirus were grown in the UK and 19 of those 24 samples contained NoV GI. Seven/310 (2.3%) samples of fresh raspberries were Norovirus-positive. Most (6/7) of the positively-testing fresh raspberry samples were imported, but no predominance of a genogroup, or any seasonality, was observed. Ten/274 (3.6%) samples of frozen raspberries were Norovirus-positive. The country of origin of the positively-testing frozen raspberry samples was not identified in most (7/10) instances. The collected data add to the currently limited body of prevalence information on Norovirus in fresh produce, and indicate the need for implementation of effective food safety management of foodborne viruses.

A highly sensitive ultra-high performance liquid chromatography/tandem mass spectrometry method with in-source fragmentation for rapid quantification of raspberry ketone

Raspberry ketone (RK) is the characteristic aromatic compound in raspberry (Rubus idaeus L.) with wide applications as food additive and anti-obesity agent. However, quantification of RK has presented difficulties in MS detection and reliable LC-MS method for RK analysis in literature is in limit to date. In order to facilitate quality control of raspberry derived products and RK metabolomics study, this study aimed to develop a validated and sensitive UHPLC-MS/MS method. Strong in-source fragmentation was noted and the fragmental ion of 107 m/z produced was selected as the precursor ion for MRM detection, and as such the electrospray ionization performance was optimized by fractional factorial design to accommodate such ion-source dissociation behavior as well as its moderate volatility. A pathway involving the formation of quinone-like structure with strong conjugation was proposed to explain the intense in-source fragmentation. The MRM transition was optimized with product ion of 77 m/z selected as the quantifier ion. The method featured low limit of quantification of ∼2 ng/mL and allowed for rapid detection of RK in fresh raspberries following direct sample preparation. RK contents were found to be higher from locally grown and harvested farm sources compared to commercial products shipped into the state, and higher in those at late-stage compared with early-stage maturity. No correlations in RK content between organic and non-organic labels were noted.

Inactivation of murine norovirus and hepatitis A virus on fresh raspberries by gaseous ozone treatment

Raspberries are vulnerable products for which industrial treatment solutions ensuring both food safety and sensory quality are not easily applicable. Raspberries have been associated with numerous foodborne outbreaks in recent decades. Ozone has been proven effective as a drinking water treatment against pathogenic microorganisms. Nevertheless, to date, little information is available regarding the effect of gaseous ozone on viruses in food matrices. A comparison of the effect of gaseous ozone on murine norovirus (MNV-1) and hepatitis A virus (HAV) adsorbed on fresh raspberries was performed. Infectious MNV-1 was highly inactivated (>3.3 log10) by ozone (3 ppm, 1 min). The raspberry matrix seems to enhance inactivation by ozone compared to water. The same treatment was observed to have little effect on HAV even for the highest dose under the tested conditions (5 ppm, 3 min). Ozone treatment (5 ppm, 3 min) did not affect the appearance of raspberries even after three days post-treatment. No ozone effect was observed on the genomes detected by RT-PCR on both tested viruses, irrespective of the matrix or tested doses used. Gaseous ozone could therefore be a good candidate for human norovirus inactivation on raspberries but new conditions are needed for it to have significant effects on HAV inactivation.

Cost-effectiveness assessment of dried raspberry production

This paper analyses different cost-effectiveness aspects of dried raspberry production. The drying performed was convective using straw as the main source of heat. A relatively small dryer, favorable for family farm production, was used with a capacity of 400 kg of raw material per day. The duration of raspberry drying is 15 days, whereas the duration of fruit drying season amounts to 135 days a year. Fresh raspberries, as the main raw material, have the greatest impact on the production costs of dried raspberry, with a share of 63.7 %, followed by significant packaging costs (28.3 %), labor costs (4.73 %) and energy consumption costs (1.21 %). Such cost structure primarily results from using straw as the main energy source, inasmuch as straw is considerably less expensive than other available fuels. The analysis shows that in the 15-days production of dried raspberries is realized a profit of around 6,210 €, which can be considered as a very good financial result. Furthermore, the economics of production coefficient is 1.41 and the rate of production accumulation is 28.8 %.

Growing, not blowing, raspberries

Rich in colour and wonderful to taste, fresh raspberries are both delicious and healthy. Learn how to successfully grow and care for them and many fun ways to eat them.

The impact of pulsed light on decontamination, quality, and bacterial attachment of fresh raspberries

Raspberries have served as vehicles for transmission of foodborne pathogens through fecal-oral route and have resulted in 11 outbreaks in the United States from 1983 through 2013. However, because of its dedicated structures and perishability, water based sanitizer washing cannot be used for raspberry decontamination. As a non-thermal technique, pulsed light (PL) may have the potential to maintain both safety and quality of fresh raspberries. The first objective of our study was to investigate Salmonella and Escherichia coli O157:H7 inactivation efficacy of pulsed light (PL) on fresh raspberries during 10 days storage at 4 °C. The qualities of raspberries after PL treatment, including color, texture, total phenolic content (TPC), total anthocyanin content (TAC), total bacteria count (TBC) as well as total yeast and mold count (TYMC), have also been evaluated during the 10 days storage. Compared with the untreated control, all the PL treatments (5 s, 15 s and 30 s) maintained lower pathogen survival population during 10 days refrigerated storage. At day 10, all PL treated raspberries maintained significantly lower TBC and TYMC than the control. Although PL treatment for 30 s (with fluence of 28.2 J/cm2) reduced most Salmonella and E. coli O157:H7 right after treatment, by 4.5 and 3.9 log 10 CFU/g respectively, it failed to maintain its advantage during storage. In addition, color and texture of these raspberries changed negatively after 10 days storage. PL 30 s provided the lowest TBC and TYMC at day 0, but failed to maintain its advantage during storage. To consider both safety and quality of fresh raspberries as well as the treatment feasibility, 5 s PL treatment with fluence of 5.0 J/cm2 was recommended for decontamination. The second objective was to study attachment of bacteria as well as decontamination effect of PL on raspberries. Under the scanning electron microscopy (SEM), PL showed severe damage to the cell membrane on smooth surface. Surface structure of raspberries affected the attachment of bacterial cells and the surface roughness provided protection for pathogenic bacteria. Our research demonstrated for the first time that successful PL processing of raspberries should be evaluated for its impacts on both produce safety and quality during the storage. PL with fluence of 5.0 J/cm2 maintained both safety and quality of fresh raspberries during the refrigerated storage.

Raspberry fresh fruit quality as affected by pectin- and alginate-based edible coatings enriched with essential oils

The effects of optimized edible coatings based on sodium alginate (AL) or pectin (PE) with the essential oil constituent additives, citral (Cit) and eugenol (Eug), were studied on fresh raspberries quality during storage at 0.5°C. Several formulations of edible coatings were used as treatments: AL and PE were tested at 1% and 2% (w/v) with Cit and Eug at minimum inhibitory concentrations (MIC) (0.15 and 0.1%, respectively), at double the MIC concentration and their combination at MIC. Raspberries were immersed in each solution (treatment) for 2min, and then cooled at 0.5°C. On days 0, 7, and 14th, samples were removed and used for the following physicochemical and biochemical analysis: color CIE (L*, °hue), firmness, soluble solids concentration (SSC), weight loss, trolox equivalent antioxidant capacity (TEAC), microbial growth, and taste panels. Color parameter L* and TEAC were not significantly affected by the coatings. Cit at higher concentrations reduced °hue and firmness and increased weight loss. The SSC decreased mainly in controls. Edible coatings enriched with Cit and Eug were effective at reducing microbial spoilage. Taste panels showed lower scores in Cit 0.3% treatments and raspberries were considered not acceptable after 14 days storage. No significant differences were observed between PE and AL. Raspberries immersed in water (control+water) performed worse than fruit stored without any immersion or wash (control). With the results of the physicochemical and biochemical parameters measured, 3 similar treatment groups were formed by the principal component analysis (PCA) and hierarchical cluster analysis (HCA), either for AL or PE coatings. The group which had better performance was selected for AL- and PE-based edible coatings. From each group the two best edible coating formulations with the higher sensory evaluation were selected. Those confirmed that raspberries were better preserved in terms of general sensory attributes with coatings of AL 2%+Cit 0.15% and AL 2%+Eug 0.1%, and with PE 1%+Eug 0.1% followed by PE 1%+Cit 0.15%+Eug 0.1%.

Chitosan applications pre- or postharvest prolong raspberry shelf-life quality

Raspberries are fruit with high metabolism that makes them very perishable, impairing their storage and shelf-life. Chitosan coatings have the potential to improve their postharvest life by reducing water loss, respiration rate and decay incidence. The purpose of this work was to study the effect of different concentrations of chitosan, applied pre- or postharvest, on the retention of quality attributes of fresh raspberries. The chitosan concentrations tested were 0 (control), 0.5, 1.0 or 2.0%. The postharvest treatment was applied immediately after harvest, dipping the fruit in the solutions for 5min. The pre-harvest treatment was done with one hand-spray application per week for three weeks, starting when the fruit were just turning pink. In both experiments the fruit were stored at 0°C and 90% RH. Pre- or postharvest use of chitosan at 1 or 2% was effective in maintaining titratable acidity and retarding respiration and ethylene production, weight loss and decay incidence. Application by both means resulted in the highest chitosan concentrations accelerating a reduction of ascorbic acid contents. Firmness was maintained only when the fruit were treated pre-harvest at 2%. Thus, application of chitosan at 1 or 2% postharvest and 2% pre-harvest was able to retain key raspberry quality attributes for 15 and 12 days, respectively.

Viennese consumers' preferences and willingness to pay for raspberries from Arilje, Serbia

Raspberries from Serbia have a good reputation and those from Arilje are protected by a geographical indication registration within the state of Serbia. Recently, producers and other stakeholders have been considering promoting this Geographical indication (gi) produce outside of Serbia, and Austria is one of the main target markets. The export of fresh raspberries is, generally speaking, only in its initial phase, and protecting raspberries from Arilje by geographical indication also in the eu is seen as a good opportunity for the whole western area of the country. It is widely recognized that gi labels may work as a quality signal for food products and may be useful to build trust among consumers. In this study, we aim at evaluating the role of a gi label in shaping consumer purchase intentions, using a conjoint choice experiment approach. The attributes we considered were price, punnet size, geographical indications of origin (from major production areas in Serbia, Poland, and Spain), and method of production (organic, integrated crop management). A survey were administered to a sample of 235 consumers in Vienna. The probability of choice was modeled using a discrete choice approach that allowed us to quantify consumers’ preference for different attributes and levels, as well as willingness to pay for raspberries from Arilje, Serbia compared to other areas of origin. Our results suggest that Viennese consumers have a positive attitude towards raspberries from Arilje, Serbia and they are, coeteris paribus, willing to pay more for them compared to other foreign areas of origin. However, willingness to pay is slightly higher for organic raspberries than for gi labeled raspberries. This could imply that a combination of strategies, rather than focusing on gi labeling only, may be more beneficial for Serbian producers.

Gamma radiation: An efficient technology to conserve the quality of fresh raspberries

Raspberries have short postharvest life and decay rapidly. A technology that is increasingly being used to inhibit the growth of these microorganisms and simultaneously delay fruit senescence is gamma ray irradiation. The aim of this study was to evaluate the effectiveness of this technology in cold-stored fresh raspberries postharvest and to find the best irradiation dose. Raspberries were purchased from a commercial orchard. The doses applied were of 0.5, 1.0 or 2.0kGy, and the fruit was stored at 0°C and 90% RH after the irradiation. Non-irradiated fruit was used as the control. The results indicated that the application of gamma rays did not alter the respiratory rate, ethylene production, flesh firmness, anthocyanins content or color index of the raspberries. The use of gamma radiation in doses of 1.0 and 2.0kGy, associated with cold storage, extended the postharvest life of fresh raspberries by 8 days. The 1.0kGy dose is considered the most useful one that reduces the decay incidence and weight loss and presents the lowest reduction in ascorbic acid. However, to recommend its use, it is necessary further studies about the effect of this dose in the bioactive and nutritional compounds of the raspberries.