**6.1 Consumer acceptance**

Currently, there is not yet a large market demand for irradiated foods in the US and the rest of the world. In spite of additional of safety benefits offered by irradiation, marketing of irradiated foods has not been successful; in part due to consumers' believe that irradiated foods form harmful compounds in food (Oliveira & Sabato, 2002). The terms "radiation" and "radioactivity" have negative connotations to many consumers. Occasionally, consumers believe that food become radioactive after irradiation. Food does not become radioactive as the energy passes through; it only destroys bacteria and does not leave behind any residual radioactivity. There are anti-food radiation activists campaing against the public acceptance of irradiated food. It is crucial to educate the consumers and highligh*t* the benefits of irradiation, particularly since the public has indicated to be more receptive to the negative argument (Fox, 2002; Hayes et al., 2002). It is indicated that given the preference and the

2002). According to Scott J. S, and P. Pillai, 2004, **v**itamins have been shown to keep considerable levels of activity post irradiation. In general, proteins, lipids, and carbohydrates quality is not get affected as a result of irradiation (Thayer, 1990; Thayer et al., 1987; WHO, 1999). The nature and extent of the effects of ionizing radiation on nutrients depends on the composition of food, radiation dose, and modifying factors such as temperature and presence or absence of oxygen. It has been documented that minerals are also stable to irradiation ((Diehl, 1995). According to a report by Fan and Sokorai, 2002, irradiation can reduce vitamin C in some vegetables, but the decrease is usually inconsequential and does not exceed the decline seen during storage. Research on vitamin B6 has shown less destruction of this vitamin in products sterilized by ionizing energy than by heat (CAST, 1986). Follet and Sanxter (2002) studied the tropical fruits and found papayas, rambutans, and Kau oranges were acceptable when treated with a quarantine level of 0.75kGy (minimum dose required is 0.25 kGy). Irradiation is also reported to increase phenol compounds of certain vegetables consequently increasing their antioxidant ability

Fresh produce may loss firmness after irradiation (Gunes et al., 2000; Palekar et al., 2004). However, the softening of fresh produce can be lessened by combining different treatments. According to Gunes et al., 2000; Prakash et al., 2007, dipping diced tomatoes and fresh-cut

Generally, fresh produce indicate little change in appearance, flavor, color, and texture, after low doses (1 kGy or less). It has been reported that irradiation does not increase the temperature significantly and therefore, there is retention of color, flavor and textural properties (Willis, 1982). In a previous study, celery irradiated at 1kGy, was suggested to be better-quality in sensory qualities as compared to celery subjected to blanching, chlorination, and acidification (Prakash, 2000). Follet and Sanxter (2002) found that Chompoo and Biew Kiew fruit to be more satisfactory when treated with 0.40 kGy than with

Currently, there is not yet a large market demand for irradiated foods in the US and the rest of the world. In spite of additional of safety benefits offered by irradiation, marketing of irradiated foods has not been successful; in part due to consumers' believe that irradiated foods form harmful compounds in food (Oliveira & Sabato, 2002). The terms "radiation" and "radioactivity" have negative connotations to many consumers. Occasionally, consumers believe that food become radioactive after irradiation. Food does not become radioactive as the energy passes through; it only destroys bacteria and does not leave behind any residual radioactivity. There are anti-food radiation activists campaing against the public acceptance of irradiated food. It is crucial to educate the consumers and highligh*t* the benefits of irradiation, particularly since the public has indicated to be more receptive to the negative argument (Fox, 2002; Hayes et al., 2002). It is indicated that given the preference and the

apples in a calcium solution prior to irradiation prevents the softening of the tissue.

(Fan, 2005).

**5.2 Sensory quality of fresh produce** 

the currently used hot-water immersion.

**6. Challenges of food irradiation** 

**6.1 Consumer acceptance** 

access to irradiated products, consumers are willing to purchase them in noticeably great numbers (Bruhn, 1995).

#### **6.2 Gamma Irradiation and cost of food**

The principal economic challenge of food irradiation is the projecting of market demand for irradiated fresh produce. A strong market demand, will attract investors absorb the large up-front costs needed to support food irradiation. Definitely, economic considerations are some of the factors that slow the widespread use of food irradiation. As any other food process, food irradiation adds a few cents per pound to the cost of production (http://www.fipa.us/q%26a.pdf Food Irradiation Processing Alliance).

Contributing to the limited marketing of irradiated food in USA, is the insufficient food irradiation facilities. As of August 2000, there were only two facilities in the United States used primarily for gamma irradiation of food. (GAO-10-309R. 2010. Federal Oversight of Food Irradiation (http://www.gao.gov/new.items/d10309r.pdf). It is costly to build an irradiation facility**.** A commercial food irradiation plant is in the range of \$3 million to \$5 million, depending on its size and processing capacity. Consumer reception of novel food technologies depends on risks and benefits associated to the new technology and reachable alternatives. Some consumer are attracted to purchase irradiated produce by the discernment that irradiated it is safer. Irradiated produce tend to have longer shelf life hence less storage losses. The cost of irradiated food could be offset by benefits such as keeping a product fresher longer and enhancing its safety (http://ag.arizona.edu/pubs/health/ az1060.pdf.

#### **6.3 Regulatory approval and labeling**

Labeling of irradiated food has been considered indispensable in order to inform the consumers. Labeling laws of irradiated foods differ from country to country. In the U.S., as in many other countries, irradiated food are labeled as "Treated with irradiation" or "Treated by radiation" and require the use of the radura symbol at the point of sale in (Xuetong et al, 2007). Fresh produce should have the radura symbol displayed at the point of sell. For fruits and vegetables, radura symbol can be on each piece, on the shipping container, or on a sign near the merchandise. Analytical methods are used by government and regulatory agencies to determine irradiated foods in the market place (CODEX STAN 231, 2003)*.* Using these methods, existing labeling principles are imposed and consumers' confidence is strengthened

#### **6.4 Consumer education**

Consumers' knowledge about food irradiation is insufficient and therefore, education is desired to improve the acceptance of irradiated food by the public. Consumers are confused over what food irradiation and studies time and again display that when provided with science-based information, a high percentage of consumers favor irradiated foods. Food irradiation, pasteurization, canning, freezing, and drying are means of treating food in order to make it safer to eat and longer lasting (Satin, 1993). Despite its advantages, consumer knowledge about it is very limited. Many consumers' fears or misunderstanding of food irradiation are from reports of nuclear incidents at Hiroshima (Japan), Chernobyl (USSR),

Gamma Irradiation for Fresh Produce 259

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and the Three Mile Island (United States) and from nuclear waste disposal. For many, food irradiation is a process that creates the same fear as the word, radiation. Some consumers mistake the association of food irradiation with nuclear radiation, and food irradiation opponents use this as their most effective tool of negative influence. During food irradiation, food is not in contact with radioactive source and therefore, food can not be radioactive (FIFA, 2006).

Conley (1992) advocates that in the US, the Food Safety and Inspection Service FSIS and the National Agricultural Library in cooperation with other food-related agencies such as the FDA should provide education materials to consumers regarding food irradiation. Consumers favor food irradiation after they are given science-based information including product benefits, safety and wholesomeness of irradiated products (Bruhn, 1998; Bruhn, C.M., and Schutz, H.G. 1989). Previous studies indicate that educational activities and science-based information increase consumer acceptance of irradiated foods (Resurreccion et al., 1995; Bruhn, 1998; Fox & Olson, 1998). Nayga et al. (2004) reported that consumers are "willing to pay" premiums for irradiated food depending on the awareness and background information of food irradiation.
