Chemical composition of food products derived from wheat and corn produced in Costa Rica

Twenty one wheat and corn based food products elaborated in Costa Rica were analyzed by chemically with the purpose of having data on local foods. The analytical methods to determine proximate composition were AOAC's. Energy was estimated by calorimetric bomb and dietary fiber (DF) by the gravimetric enzymatic method. Also food portion size was estimated and related with DF content for food classification. The values of the nutrients per food were established and compared with others reported in foreign tables commonly used in the country. Fat and energy content in cookies are higher than in salad breads and crackers. Wheat and corn based food products are classified either as low or very low DF sources (< 2.9 g FD/portion). Corn "tortilla" DF content duplicates bread's and the fiber is basically insoluble. Marked differences were founded in the nutritive composition of specific foods when compared with values reported in foreign food tables. In other foods, as corn based products, similarities in the chemical composition were common. The chemical composition of the studied local foods shows the potential of the diet to be atherogenic, an important aspect to be considered with relation to the main causes of mortality in Costa Rica population. The more compatible food composition table with our data is the Central American, followed by the Latin American one. The necessity of having data on the chemical composition of local foods has been demonstrated.     

Evolution of the nutritional and food situation of the metropolitan area of San Jose, Costa Rica]

Evolution of food and nutrient intake patterns in urban San José, Costa Rica, during the last decade, was studied comparing data from the last two national surveys (1978, 1982) and 1987 data obtained from 5 families previously included in the 1982 survey. Total food and nutrient intake was found to be similar to the 1982 results, although the pattern was altered, with a substantial decreased contribution of milk products to both energy and protein intakes. A small but constant decrease in the intake of more than half of the foods registered was also observed. Nevertheless, the nutritional adequacy of energy (from 100 to 78%), retinol (from 83 to 69%), riboflavin (from 94 to 63%), iron (from 106 to 69%) and niacin (from 103 to 81%), were found to be significantly lower than in previous years. The findings herein reported suggest that the effects of the economic crisis initiated in 1980 on food availability, could well be showing a time lag.     

Prevalence of nutritional anemia in women of reproductive age. Costa Rica. National nutrition survey, 1996

In 1996, The Ministry of Health and Inciensa conducted the latest National Nutrition Survey, to provide support and guidance to the national policies, plans and programs in the field of food and nutrition. The present paper reports the results for the prevalence of anemia estimated in a total of 884 women of reproductive age, in three areas: metropolitan area, other urban areas and rural areas. Anemia was determined through measurements of hemoglobin, plasma ferritin and plasma folates. In addition, hemoglobin patterns were determined by electrophoresis. The cutt-off points used were those recommended by the WHO. Anemia was present in 18.6% of the women. Severe to moderate deficiency of iron (< 12 ng/dl) and of folates (< 6 ng/dl) were found in 43.2 and 24.7% of women respectively, with statistically significant differences by area of residence. The magnitude of the problem for anemia can be classified as mild, for iron deficiency as severe, and for folate deficiency as moderate. In conclusion, Anemia represents a public health problem for Costa Rica that has remained constant throughout the last decade. In women of reproductive age, iron deficiency is the main cause of Anemia, followed by folates deficiency, and in a small percentage hemoglobinopathies. Intestinal parasites are not longer a mayor cause of Anemia. Prevalence of Anemia is influenced by place of residence, but not by age. In summary, despite the favorable health conditions present in Costa Rica, the prevalence of Anemia and of iron deficiency are similar to those of the Latin-American region. To improve this situation, public health interventions are necessary.     

Microbiological quality of home-made cheese produced in Costa Rica

The microbiological quality of 205 samples of home-made cheese prepared from raw milk in six rural zones of Costa Rica was studied. In addition to determining their microbiological quality, recommendations are also issued for reducing to a minimum, the deficient sanitary conditions under which they are produced. Collection of samples was done directly at the producing farms. The following microbiological analyses were then undertaken: Staphylococcus aureus, thermonuclease (TNase) positive. Determination of most probable number (MPN) of coliform organisms of fecal origin. Total count of molds and yeasts, and Enumeration of mesophilic aerobic bacteria. As the data revealed, all samples contained high counts of the four microorganisms investigated, therefore demonstrating the deficient microbiological quality of the home-made cheese. On the basis of results obtained, a series of practical recommendations are suggested to improve the poor sanitary conditions under which they are now prepared.     

Microbiological stability through storage period of Sphyraena ensis in Costa Rica

At the present study some of the microbiological and biochemical changes that occur through storage period in Sphyraena ensis, a fish specie of frequent consumption in Costa Rica were studied. Samples of S. ensis obtained during rainy and dry season were evaluated. Analysis included aerobic psychrotrophic count, identification and count of Vibrio, Enterococcus and Pseudomonas through a six day storage period at two different refrigeration temperatures, 2 and 7 degrees C. Same time, a commercial enzymatic immunoassay was used for the evaluation of the variation on the concentration of histamine produced in the different samples. Results obtained show that there is an increase on the bacteriological counts through the storage period, this increase is bigger as refrigeration temperature increases. Most of the samples maintained at 7 degrees C showed counts above 106 CFU/g after three days of storage, those stored at 2 degrees C did not present such high population levels. Nevertheless, after 6 days of storage, all samples, despite the storage temperature used, presented levels above the described one. Also, an histamine concentration increased through storage time, especially when the product was conserved at the higher temperature due to an increase in the number of histidine descarboxilating bacteria. There is no statistical difference between the counts obtained during rainy or dry season; nevertheless, there is a difference assicieated to the bacterial genera isolated.     

Lipid and lipoprotein profile of Chinese immigrants living in Costa Rica

The lipid profile and food pattern of 50 Chinese immigrants living in San José, Costa Rica were studied during 1999. The results showed that 35% of the immigrants had high levels of total cholesterol (> or = 5.16 mmol/L) and 51% had high concentrations of LDL-Cholesterol (> or = 2.84 mmol/L). Moreover, 36% of them had high levels of triglycerides (> 1.69 mmol/L) and only the 15% had low concentrations of HDL-cholesterol (< or = 0.90 mmol/L). The ratio of men with high levels of total cholesterol, LDL-cholesterol and triglycerides and low levels of HDL-cholesterol was larger that the one in women; although this difference was not significant. 41% of the studied population presented Castelli's Indexes (TC/HDL-C) above 4.5. In general, around 80% of the Chinese immigrants consume vegetables 5-6 times/week and 50% consume fruits with the same frequency. A high percentage of the immigrants eat food with animal protein more than 3 times/week and around 23% eat frequently snacks and fast foods. Our data suggest that the Chinese immigrants still keep some characteristics of their nutritional culture. Nevertheless, they have changed their food pattern to a more atherogenic one. It's important that nutritionists and other health professionals evaluate in detail the factors associated with the change in the food pattern of the immigrants, in order to avoid an increase in the rates of morbi-mortality of coronary disease in this group of population.     

Nutritional and microbiological profile of soybean sausages available in Costa Rica

The nutritional and microbiological quality of 80 soybean sausage samples (50% frankfurter and 50% sausage mortadela) was studied. On average, the protein content was 17.5 g/100 g in sausage mortadela and 20 g/100 g in frankfurter. The mean total fat content was 5.5 g/100 g for both products. However when products of different manufacture industries were compared, a highly significant difference (p = 0.0000) in the fatty acids speciation between both groups and between samples of the same product were found. Bigger differences were found in the content of palmitic acid (C16:0), oleic acid (C18:1) and linoleic acid (C18:2). Cholesterol was not detected in samples analyzed. On average the atherogenicity index was 0.55 for sausage mortadela and 0.59 for frankfurter. A consumption of 25 grams of of soybean protein from these sausages can bring an intake of saturated fatty acids between 20-90% of the daily recommendation. Likewise, they can supply between 12-70% of the recommended daily polyunsaturated fatty acids. These variations are owing to the big difference in fatty acids speciation in each sausage brand. Around 20% of soybean sausages studied showed total coliform levels above 10(4)/g, being more frequent in sausage mortadela. Also 60% of this product and 10% of frankfurters showed psychrotroph levels of 10(6)/g. Clostridium perfringens, in levels above 10(2)/g was evidenciated in 5% of samples, Escherichia coli was not isolated from them. The findings of this study suggest the urgent need for implementing a quality control system for soybean sausages, before national health authorities consider to support nutritional campainings that promote their consumption.     

Chemistry of venom alkaloids in the antMegalomyrmex foreli (Myrmicinae) from Costa Rica

Chemical analysis of the venom of the myrmicine antMegalomyrmex foreli from Costa Rica revealed the presence of four major alkaloidal components. Two of these, 2-butyl-5-(E, 1-heptenyl)-5-pyrroline (3) and 2-butyl-5-(E, E, 1,3-heptadienyl)-5-pyrroline (4), constitute a new functional class of ant venom alkaloids, whose structures were assigned from their spectral and chemical behavior and unambiguous syntheses. The function of these compounds is suggested by field observations of the behavior ofM. foreli, its sting morphology, and the relative toxicity of 3 and 4 against termite workers.     

Determination of clostridium perfringens in pork sausages from the Metropolitan area of Costa Rica

The presence of C. perfringens was analyzed in 75 samples of pork sausages (chorizo, salchichon and bologna), obtained from five processing plants located in the Metropolitan Area of Costa Rica. Previously and after the biochemical identification of the strains, the most probable number (MPN) of C. perfringens per gram of food was determined and it varied from less than 3 to more than 2.4 x 10(5). There were significant statistical differences (p < 0.005) that support the need of employing biochemical tests for confirming C. perfringens in a given food. C. perfringens was present in 92% of the chorizos, in 28% of the bolognas and in 12% of the salchichon. Every positive sample was tested looking for at least one enterotoxigenic strain, using the reverse passive agglutination latex test; 8% of the tested strains were enterotoxigenic and corresponded to chorizo and bologna from one processing plant and chorizo from another plant. The results obtained in this study show that pork sausages, and not just not processed meats, are important as risk factors for food intoxication by C. perfringens.     

Bacteriological quality of traditional, organic and hydroponic cultured lettuce in Costa Rica

The main objective of this work was to evaluate the microbiological quality of lettuces commercialized in the Metropolitan Area of San José, Costa Rica, and cultured in different ways, in order to detect differences between the culturing methods and the risk that these products may represent for Public Health. The study was done at the Food Microbiology Laboratory, Universidad de Costa Rica, from March to July, 2010. 30 lettuce samples were analyzed (10 obtained by traditional culture, 10 by organic culture and 10 by hydropony). All samples were obtained from markets where their origin was certified. Total aerobic plate count, total and fecal coliforms count and Escherichia coli were determined to all samples, as well as the presence/abscense of Salmonella spp. and Listeria monocytogenes in 25 g. Results obtained show that there is no statistically significant difference (p < 0.001) between the different types of cultures analyzed for any of the parameters evaluated. An important percentage of the samples presented coliforms, nevertheless, just one E. coli strain was isolated from a traditionally cultured lettuce sample. Four different Salmonella spp. strains were isolated from the samples as well as one Listeria monocytogenes strain. Data obtained show that the consumption of this product, raw or without an adequate hygiene and disinfection may represent a risk for health. Also, from the bacteriological point of view, there is no significant difference between the culturing methods evaluated, suggesting that the specific directions for each type of culture are not followed or that there is an inadequate handling of the products or post harvest contamination.     

Clostridium perfringens in raw and cooked meats and its relation with the environment in Costa Rica

The presence of Clostridium perfringens in eight slaughter houses from Costa Rica was analyzed using the Most Probable Number (MPN) technique, in order to assess the risk of acquiring a food borne intoxication due to consumption of contaminated meat. C. perfringens was detected in 29 (88%) out of 33 soil samples collected from the slaughter house surroundings (average 6.7 x 10(2) MPN/g), as well as in 70 (93%) out of 75 intestinal contents of slaughtered animals (average 3 x 10(4) MPN/g), in 42 (55%) out of 76 samples of slaughtered meat (average 2.2 x 10(4) MPN/g) and in 30 (61%) out of 49 retail meats (average 8 x 10(3) MPN/g). In addition, the presence of this bacterium was evaluated in ten retail meat markets located in the Metropolitan Area of Costa Rica, where it was isolated from 15 (75%) out of 20 samples of ground meat and from 28 (36%) de 78 stew meat samples (average 1.9 x 10(3) and 7.5 x 10(2) MPN/g, respectively). Only one out of 35 samples of cooked meat obtained from 32 restaurants that utilize heated water baths (average temperature of 82 degrees C) was positive for C. perfringens (4 MPN/g, temperature 72 degrees C). Out of 1121 bacterial isolates obtained, 250 were evaluated for enterotoxigenicity. Only 3 (1.2%) of these tested positive for enterotoxin production, probably because most wild strains are not toxin producers, even though they can be induced to produce it as a result of repeated thermal shocks. The present results urge the adoption of adequate preventive measures and high sanitary standards in the meat processing industry in Costa Rica, in order to minimize the risk of food-borne intoxications caused by C. perfringens, due to its widespread distribution and potential human health hazard.     

Evaluation of the bacteriological quality of ice cream sold at San Jose, Costa Rica

The presence of total and fecal coliforms, E. coli, Listeria sp and Salmonella sp. was evaluated in 65 samples of both commercial and homemade ice cream. 37.1% of homemade ice cream and 20% of commercial ice cream did not fulfill the international standard for total coliforms. At the same time 82.9% of home made samples and 56.7% of commercial ones presented fecal coliforms. E. coli was found in 51.4% of home made samples and 26.7% of commercial ones. Sixteen Listeria sp. isolates were obtained, 50% corresponded to Listeria monocytogenes and 50% to L. innocua. The overall presence of L. monocytogenes in ice cream samples was of 12.3% and it was isolated in all cases, from homemade ice cream samples. Salmonella was not isolated from the samples analyzed. Although the results obtained show an important improvement in the quality of ice cream, compared with a previous work done also in Costa Rica, further efforts shall be done, in order to offer safe products to consumers.     

Chemical composition and biological value of tortillas and bread produced on the commercial level in Costa Rica

A study was conducted to evaluate the nutritive value of tortilla, wheat bread, and tortilla meal. Six types of tortillas, five breads and two tortillas meal were thus studied. Chemical composition of each product was determined, and biological trials in laboratory rats were also carried out with each of them. Results demonstrated that the corn products had a better protein quality than the wheat products. Furthermore, little variability in nutrient content and protein quality (NPR) between the different corn and wheat products was found. The utilizable protein content of the wheat products was higher than that of the corn products, while the gross energy content was similar for both. An economical-nutritional analysis revealed that the corn-soybean tortilla meal is the most nutritive and economic product to provide basic nutrients (protein and energy) to the population.     

Kiln drying behavior utilizing drying rate of lumber from six fast-growth plantation species in Costa Rica

The objective was to study the effect of the drying time and moisture content variations on the drying rate during kiln drying. The moisture content is a good predictor of the variation in drying rate; to determine the drying rate, the model DR =a * t + b (where DR is the drying rate, t is the drying time, and a and b are constants) was used. Cordia alliodora, Dipterix panamensis, Hieronyma alchorneoides, and Vochysia ferruginea show a unique tendency, whereas Enterololium cyclocarpum and Samanea saman showed two tendencies. Drying rate in relation to time showed that it is possible to define the various stages during drying and the inflexion points in time where a change in the drying rate occurs. Two types of tendencies are shown in the drying rate vs. time relation in C. alliodora, E. cyclocarpum, and S. saman, whereas three tendencies appear in D. panamensis, H. alchorneoides, V. ferruginea. C. alliodora, E. cyclocarpum, and S. saman presented only one inflexion in the drying rate, which can be maintained at an average of 24.5, 11.64, and 7.83%/day, respectively, for those species. On the other hand, D. panamensis, H. alchorneoides, and V. ferruginea showed two inflexions.     

Factors affecting the nutritional quality of soya products

The nutritional quality of soya products is determined not only by the quantity and availability of the amino acids which make up the protein of such products, but is also markedly affected by the processing conditions which are employed in their manufacture. The most important factor in this regard is the application of some form of heat treatment which serves to inactivate a number of naturally occurring constituents of the soybean. Although non-toxic in the truest sense of the word, these are substances which can nevertheless elicit adverse physiological responses in animals, and, unless destroyed, can detract from the full nutritional potential of soya protein. The best known and certainly the most studied of these factors are the inhibitors of trypsin and chymotrypsin, enzymes which play a key role in the digestion of proteins in animals. These will be discussed with respect to their possible model of action in vivo, and an attempt will be made to evaluate their nutritional significance in man. Also present in soybeans are several other heat-labile components whose physiological significance is less well understood. These include the phytohemagglutinins (lectins), goitrogens, antivitamins and phytates. Less sensitive to the destruction effects of heat are a number of factors which are capable of producing a wide variety of physiological responses in animals and include saponins, estrogens, oligosaccharides and allergens. Although present in readily detectable quantities, their effect on the nutritional quality of soya protein is questionable. Not to be overlooked is the fact that harsh processing conditions such as excessive heat treatment or extraction under alkaline conditions may lead to the destruction of economic importance at the present time, brief consideration will be given to the possible effects of germination and fermentation on the nutritive quality of the protein resulting from such treatments.     

Bacteriological evaluation of fresh tilapia (Oreochromis niloticus) coming from the northern region of Costa Rica

The following work presents an evaluation of the normal and pathogenic flora associated to tilapia (Oreochromis niloticus), since there are no previous national studies referred to the microbiological quality of this product. The total aerobic plate count, lactic bacteria, Enterococcus sp and Aeromonas sp and fecal and total coliform count, and the presence of Listeria sp and Salmonella spp from the external surface of tilapias were evaluated. A total of 50 samples, coming from San Carlos and Ca?as zones were transported in ice to the Food and Water Microbiology Laboratory, Universidad de Costa Rica, where the laboratory analysis were performed, according to the methodology presented by de American Public Health Association, 1998. The results obtained confirm the microbiological freshness of the product when the analysis was performed, although coliform levels were unacceptable. Listeria sp was not found, but the isolation of Salmonella spp. confirms the fecal contamination of water where the tilapia is grown, aside of the Public Health concern. Also, it was found a high number of Aeromonas sp, as part of its normal flora, so we recommend including this genus in the quality standards for fresh fish. According to the data obtained, there was no significant difference (95% confidence) between the total plate count, fecal and total coliforms, Enterococcus sp. and Aeromonas sp. from the samples coming from the zones of San Carlos and Ca?as.     

Presence of Clostridium perfringens in meat-based preparations in public food services in central San Jose, Costa Rica

In Costa Rica there are a large number of public food services distributed along the country, where a considerable number of people eat daily. Clostridium perfringens is a bacteria associated with foodborne illness related, especially, to meat products kept for long time at temperatures under 70 degrees C. The aim of this study was to evaluate the public food services that use water baths for keeping food hot in order to establish the presence of C. perfringens in cooked bovine meat dishes and to evaluate the enterotoxigenic capacity of the strains isolated. 81 samples of cooked bovine meat plates coming from 27 public food services, located in the Central County of San José were analyzed. The methodology described by Labbe & Harmon for the isolation of C. perfringens was used in 10 g of sample. Also, the enterotoxigenic capacity of the strains was evaluated using the passive-reverse-latex-agglutination assay from Oxoid. From the 27 public food services analyzed, eight (30%) were positive in the three samplings done, nine (33%) were positive in one or two occasions, and ten (37%) were negative all times. This implies that in 17 (63%) of the establishments studied, the bacteria was isolated at least once. From the 81 preparations studied, 37 (46%) were positive for the bacteria. The temperatures at which food was kept varied from 56 to 82 degrees C, with an average of 68.7 degrees C. From the 37 strains identified as C. perfringens, 12 (32%) were positive for enterotoxin. In conclusion, the presence of C. perfringens in bovine meat dishes, maintained in water baths, represents an important risk for public health, and the temperature at which the preparation is kept is critical for the multiplication of the bacteria.     

Nutritional characterization of carbohydrates and proximal composition of cooked tropical roots and tubers produced in Costa Rica

Tropical roots and tubers (TRT) are important staple foods in the tropics. TRT are produced by small farmers and have received only limited attention. The objective of this paper was to evaluate nutritionally important carbohydrate fractions and proximal composition of cooked cassava (Manihot esculenta), cocoyam- or tannia- (Xantosoma sp) and yam (Dioscorea alata) grown in Costa Rica. Twenty boiled samples of each TRT were analyzed for proximal composition, following AOAC protocols. Carbohydrate fractions (dietary fiber, available and resistant starch) and alpha-amylolysis rate were assessed by enzymatic methods. All TRT analyzed consisted mainly of water and carbohydrates, representing moderate dietary fiber and energy sources. They show a low protein level and contain no fat. Moisture, protein, ashes and dietary fiber contents vary significantly (p<0.01) among the three species. In terms of their proximal composition, these locally grown TRT differ from TRTs cultivated in the South Pacific area, but appear similar to other Latin American varieties. In all samples most of the dietary fiber (84-88%) is insoluble; available starch ranges between 74 and 84% of the dry matter, whereas resistant starch content varied between 0.7 and 1.7%. Amylolysis rate was similar for cassava and cocoyam, whereas a significantly slower digestion (p<0.01) was recorded for yam. Compared to values reported in the literature for other starchy foods and to gelatinized potato starch, used as reference sample, the studied TRT showed intermediate amylolysis rates. It is concluded that consumption of these TRT may be promoted in Costa Rica and other countries with a similar nutritional situation.     

Serum total homocysteine and lipoproteins levels in young adults from urban and rural areas of Costa Rica

Serum total homocysteine and lipoproteins levels in young adults from urban and rural areas of Costa Rica. This study evaluated the lipid profile and the serum levels of total homocysteine of 400 adults aged 20 to 40 years, residents of rural and urban areas of the central valley of Costa Rica. The results showed that the proportion of subjects from urban areas with high levels of LDL-C (= 4.13 mmol/L) was 11% higher than the proportion of adults from rural areas (29.2% and 18.0%, p = 0.045). On the contrary, the proportion of rural subjects with low HDL-C levels (< 1.03 mmol/ L) was higher 19% than the proportion of urban adults (56.0% and 75.3%, p = 0.001). Rural residents also showed higher serum levels of triglycerides and total homocysteine than the urban residents, although the differences were not significant (TG: 1.94 mmol/L and 2.02 mmol/L, p = 0.529; TH: 9.33 micromol/L and 9.84 micromol/L, p = 0.145). The prevalences of hyperhomocysteinemia (>15 micromol/L), hypercholesterolemia (= 5.17 mmol/L) and hypertriglyceridemia (= 1.69 mmol/L) in the studied population were 5.8%, 53.6% and 50.1% respectively. 82% of the studied population had LDL-C levels above 2.58 mmol/L and approximately 61% of the adults had HDL-C levels lower than 1.03 mmol/L. Our data suggest that the studied costarrican population has a very high cardiovascular risk. The prevalence of low levels of HDL-C (< 1.03 mmol/L), marginal levels of total homocysteine and a tendency to have high levels of triglycerides were the most outstanding cardiovascular risk factors found in this population, specially in rural subjects, which could be associated with the quality of the diet of these habitants. It is necessary to develop effective intervention strategies to promote healthy lifestyles in the population in order to reduce the cardiovascular mortality rates in Costa Rica.