BELL PEPPER: FROM FIELD TO SALAD, PIZZA AND CHOWDER

By Michael Muleme

Bell pepper, (Capsicum anuum L.) is one of the minimally processed vegetables consumed in the United States (US). Different varieties of bell pepper exist on the market ranging from the 3 or 4 lobed green types to the red, orange and yellow hybrid varieties (3). The flow of food for bell pepper involves different stages from seed production to fruit consumption. Commercial seed production involves harvesting seeds from ripe fruits by hand, modified meat grinders or industrial seed machines (1). Seeds with good germination vigor are bright yellow and sink in water (1). Water extraction, air drying and fungicide treatment of the seeds is carried out (1). The seeds are then packed and sold to both small and large scale farmers. 

 Image from http://www.fruitsandveggiesmatter.gov/month/images/pepper_2.jpg

Bell pepper is grown in warm environment [75^oF - 85^oF] (3, 5). Temperatures above 100^oF reduce pollination, fruit formation and yield (3). The crop is propagated by either direct seeding or transplants (5). The seeds and transplants are initially grown in nurseries before being transferred to the field.  Greenhouses have been adopted by most countries because they maintain a warm environment, shield crops from rain, wind and high solar radiation, retain pollinators, eliminate pests and allow production throughout the year (4, 5). Soil grown bell pepper is fumigated with methyl bromide to control soil borne diseases, nematodes, and insect pests (4). In Greenhouses the bell peppers are usually grown in soil-less cultures of partite, pine bark and peat mixes and no fumigation is done (4). Fertilizers containing phosphorus, nitrate and potassium are applied before planting (3).  Plants grow up to a height of 6 feet in 250 days (3). The plants stems need to be supported with bamboo stakes or poles from other trees after pruning (3). In non-pruned fields the plants are supported vertically by poles and horizontal twines extended on both sides of the planting row (3). Pepper flowers are naturally self-pollinated. In greenhouses, bumblebees are used to ensure high quality of fruits (4). After fruiting, non-marketable fruits are removed from plants as soon as they are observed (3). Ripened fruits are harvested 2-3 times a week (3). During harvesting fruits are cut at the junction of the fruit peduncles and the stem to reduce fruit rot (3).

 

Harvested fruits are rapidly cooled by forced air at 90-95% humidity to minimize weight loss (4). Nearly all bell pepper is harvested by hand in to bulk bins or trailers for transportation to the packing facilities (3). Pepper can also be waxed to provide surface lubrication for prevention of chafing in transit (4). During packing, the fruits are sorted to remove non-marketable ones (3).  Bell peppers are graded by size and condition; sprayed with clean water and later packed in cartons (3). Bell pepper is packed in moisture-retentive liners or in to perforated polyethylene bags (3). Bell pepper is stored at 45^oF and relative humidity of 90 to 95% (4). The fruits decay when removed from these low temperature conditions (4). Pepper should not be stored with other ethylene producing fruits as these speeds up senescence (4).

Processing is can also be done by either dehydration to prolong the shelf-life of the fruits (3). Dehydrated fruits should be protected from discoloration. Storage should be at (0-10^oC) and fruits should be treated with sulphurdioxide at 3600 mg/kg (6). Pepper is used in the manufacture of dehydrated products, pastes or sliced in to pieces to be eaten raw in salads and pizzas (2). Other methods used in the preservation of bell pepper include heating and ionized radiation (2). Recently fermentation has been used to preserve pepper be stored at room temperature (2).

Pepper cartons are packed in pellets, cooled and shipped by truck to terminal markets, wholesalers across the United States and Canada. Wholesalers market the fruits to grocery stores or restaurants (3). Consumers purchase either fresh or dehydrated bell pepper from grocery stores. The storage conditions described above should be maintained if bell pepper is not for immediate consumption. Individuals may also consume bell pepper from restaurants as pizza, chowder or salads. The domestic consumption of bell pepper in the US rose from 1766.7 pounds in 1998 to 2,240.4 pounds in 2008 (8). 34.1 per cent of the domestic consumption in the US is imported from Mexico, Netherlands, Canada, Israel and Spain (4).

 

Image is from: http://img4.myrecipes.com/i/recipes/oh/08/pepper-pizza-oh-1733614-l.jpg

 

In the US, there is an increased awareness of the nutritional, health and environmental effects of food such that most consumers demand for organic food (7). Organic foods must not be genetically engineered, irrigated or fertilized with human slurry (7). Herbicides and pesticides should not be used in fields for organic food growth three years to the onset of planting. Cover crops, crop rotation and fertilization with animal manure are recommended to improve soil fertility to reduce the risk introducing carcinogenic products in the food chain (7). Increased consumer demand of pepper is due to antioxidant compounds like polyphenols, carotenoids and vitamin C in bell pepper which are known to reduce risks of cancer and heart disease (2). The consumer’s visual impression also determines the acceptability of the product (6). Although color loss in dehydrated fruits stored at low temperatures is negligible, consumers are able to identify the change (6). Thus dehydrated bell peppers constitute a secondary market and most markets sale fresh bell pepper (6).

References

1.      Berke, G. T. 2000. Hybrid Seed Production in Capsicum. J. New Seeds 1 (3-4):49-66

2.      Cagno, D. R., R. F. Surico, G. Minervini, and D. M. Angelis. 2009. Use of autochthonous starters to ferment red and yellowpeppers (Capsicum annum L.) to be stored at room temperature. Int. J. Food Microb. 130:108–116

3.      Hartz, T. and M. Cantwell. Bell pepper production in Calfornia. University of Calfornia. Document number: 7217 http://ucanr.org/freepubs/docs/7217.pdf last accessed 22/1/2012

4.      Jovicich, E., D. J. Cantliffe, S. A. Sargent, and L. S. Osborne. 2009. Production of greenhouse-Grown Peppers in Florida. Doc. No: HS979. Available at: http://edis.ifas.ufl.edu/hs228 last accessed 22/1/2012

5.      Leskovar, D. I., and J. Cantliffe. 1993. Comparison of plant establishment method, transplant, or direct seeding on growth and yield of bell pepper. J. Amer. Soc. Hort. Sci. 118(1):17-22.

6.      Sigge, O. G., C. F. Hansmanw, and E. Joubert. 2001. Effect of storage conditions, packaging material and metabisulphate treatment on color of dehydrated green bell peppers (Capsicum annuum L.). J. food Qual. 24:205-218

7.      US Department of Agriculture. Organic production/ Organic food : Information access tools, Available at: http://www.nal.usda.gov/afsic/pubs/ofp/ofp.shtml last accessed on 22/1/2012

8.      US Department of Agriculture. US Bell & Chile Pepper Statistics, USDA economic research service: Table 1. Doc. No. 1659. Available at: http://usda.mannlib.cornell.edu/MannUsda/viewDocumentInfo.do?documentID=1659 last accessed 22/1/2012

DO YOU HAVE TO CONSUME RAW FISH PRODUCTS?

By Muleme Michael

My advice to the consumer will depend on the several factors. The factors include the country in which the restaurant is located, her health status, age and conditions like pregnancy.  The implementation of food regulations varies from place to place. In most developing countries the food regulations are outdated or human, infrastructural and financial constraints affect the implementation of food safety laws (5). The consumer should therefore not eat raw fish products in any restaurant in these countries.

In the United States and countries within the European Union where food safety standards are strictly adhered to, it may be safe to have sushi and other raw fish products in a restaurant (11). The US food and Drug code requires fish for raw consumption to be frozen at -35^oC for 15 hours or at less than -20^oC for 7 days while the European Union’s Hazard Analysis point for marine fish to be eaten raw is freezing at less than -20^oC for 24 hours (4, 14). Various studies have shown freezing to be effective against many parasites feared in raw fish products (3, 6, 8). However it should be noted that all parts of the product must be subjected to the recommended temperatures which may not be the case in all freezing facilities even within restaurants in the United States. Studies have shown that temperatures higher than -17^oC are not effective against Anisakis larvae (2, 6). Additionally freezing may not protect against allergic reactions that may develop due to ingestion of dead parasite larvae (1, 2). Thus the consumer should know that although minimal, there are chances of infection with foodborne parasites or allergy reactions from eating raw fish in restaurants that use the freezing criteria (11). Dewormers like albendazole and praziquantel have been shown to be effective against most of these zoonotic parasites (10, 11). Therefore with regular deworming, the risk acquiring foodborne parasitic infections from the consumption raw fish from restaurants is very minimal in countries where food safety regulations are strictly implemented.

A number of parasitic zoonoses are known to be transmitted through the consumption of raw fish. These include round worms (Anisakis spp.), tapeworm (Diphyllobothrium latum) and liverfluke (Clonorchis spp, and Opisthorchis spp) infestations (9, 11, 13). These are mainly endemic in the Asia (9) but the existence of these parasitic infections elsewhere cannot be ruled out. Of late many of these cases are reported due to modern diagnostic techniques like endoscopy rather than the actual increase in number of parasitic infections (11, 12). In the United States, these have been identified in travelers and immigrants (13); however, the possibility of getting these infections from sushi restaurants within the United States cannot be ruled out.  This is because fish borne parasitic infections are not reportable within the United States and no national estimates of cases have been published (9). Thus I would recommend that it is not safe for pregnant women, immune-compromised individuals, and the aged to eat raw fish products even from the restaurants. The consequences of the symptoms seen in some of the parasitic infections from raw fish consumption like anemia and gastroenteritis (11) may be fatal in pregnant women, immune-compromised, aged and infants. Additionally the treatment of these parasitic infections may harm the fetus (9). A survey done by Jones et.al (9) showed that 81.5% of obstetric-gynecologists acknowledged that eating raw fish during pregnancy is not safe. Until this is disproved scientifically, the findings of this survey should not be ignored by consumers. Similarly children may be adversely affected by these infections and allergic hazards of dead parasites in raw fish due to either their under-developed immune system or naïve immunity to the pathogens (7).

The articles by Gustafson, Houwing, Deardorff and Throm, demonstrated the effectiveness of freezing against most parasites in raw fish (3, 6, 8). Some of these experiments like that Deardorff and Throm (3) showed 100 per cent effectiveness and was published in peer reviewed journals.  Deardoff and Throm, (3) found no viable Anisakis larvae in 3545 salmon and rockfish stored at -18^OC for 1 hour. Thus freezing may be effective against larvae. The consumer should therefore worry about minimal risks due to failure to subject all parts of the fish to the recommended temperatures, equipment failure in restaurants and allergic hazards due to dead parasites. Children, immune compromised people and pregnant women should not be exposed to these risks however minimal they are. Additionally other viral and bacterial infections like hepatitis A virus, Salmonella and Campylobacter may present serious foodborne hazards especially in unhygienic restaurants.

  References:

1.       Audicana, L., M. T. Audicanna, L. Fernandez de Corres, and M. W. Kennedy. 1997. Cooking and freezing may not protect against allergenic reactions to ingested Anisakis simplex antigens in humans. Vet. Rec. 140:235

2.       Beldsoe, G., and P. M. Oria. 2001. Potential hazards in cold-smoked fish parasites. J. Food. Sci. Suppl. 66:s1100-1103

3.       Deardorff, T. L., and R. Throm. 1988. Commercial blast-freezing of third-stage Anisakis simplex larvae encapsulated in salmon and rockfish. J. Parasitol. 74:600-603

INTRINSIC AND EXTRINSIC FACTORS IN NON-FAT DRY MILK

Non-fat dry milk is whole milk from which moisture and cream have been removed. This product still contains the other nutrients like minerals, vitamins, natural sugar and high quality protein; milk fat is content left ranges from 0.6 - 1.25% of total product weight (1, 3). The reduced moisture content (2.0 – 4.5 % of total product weight) or low water activity in dried milk will prevent microbial growth and spoilage (1, 3).  Exposure of the product to moisture will cause caking, undesirable changes in flavor and increased microbial growth which may result in food borne illnesses (1). Non-fat dry milk is also canned under nitrogen and carbon dioxide to exclude oxygen thus preventing microbial growth, browning and change of flavor due to oxidation of dried milk (1, 2). Additionally, milk proteins lactoferrin and lactoperoxidase have known anti-microbial properties.

Storage temperature for dry milk depends on the time the product is to be stored. Products that are to be shelved for 3, 24 and 48 months should be shelved at 90^o, 70^o and 50^oF respectively to prevent microbial growth (1).  The dry milk product should also be stored in an air tight container and a cool dry dark place with less than 65% relative humidity. Exposure to light will accelerate undesirable chemical changes (1).

References

1.      Charlotte, P. B. 1992. Utah State University Cooperative Extension: Storage of dry milk products. Document no. FN177. Available at: http://extension.usu.edu/files/publications/publication/FN_177.pdf. Last accessed on 27/1/2012

2.      Henrik, S., B. R. Nielsen, and L. H. Skibsted. 1997. Effect of heat treatment, water activity and storage temperature on the oxidative stability of whole milk powder. Int. Diary J. 7:331-339

3.      United States Diary Export Council. Nonfat dry milk and skimmed milk powder. Document no. 82271. Available at: http://www.usdec.org/Products/content.cfm?ItemNumber=82654&navItemNumber=82271. Last accessed on 28/1/2012