Search

Quality protein maize (QPM), with twice the amount of tryptophan and lysine than conventional maize, has improved the nutritional status of severely malnourished children. This double-blind clinical study evaluated the impact of QPM on the growth and morbidity of mild and moderately malnourished children. In a Nicaraguan day care center, 48 children 1 to 5 years old who were malnourished (> 2 indicators with < -1 Z for weight-age, height-age or weight-height) were identified and randomly assigned to consume for 5 days/week for 3.5 months a snack prepared with QPM or conventional maize. QPM positively influenced children's growth: weight (0.80 vs. 0.19 kg gained from baseline to endline between the QPM and conventional maize groups, respectively), height (2.02 vs. 1.23 cm in QPM vs. conventional) and Z score for weight-age (0.17 vs. -0.26 Z in QPM vs. conventional) and height-age (0.06 vs. -0.23 Z in QPM vs. conventional). When other factors that could affect growth with respect to weight, height, weight-age Z score and height-age Z score were controlled for, the intervention group (QPM > conventional) was a statistically important factor (P < 0.01). The QPM snack, however, had no effect on the incidence of diarrheal episodes or respiratory infections. In conclusion, QPM improves the nutritional status of pre-school children who are mild or moderately malnourished but has no effect on the incidence of diarrheal episodes or respiratory infections.

The 1973 FAO/WHO Joint Expert Committee on Energy and Protein Requirements has recommended two methods to adjust the safe level of protein intake according to protein quality: chemical score and net protein utilization (NPU). However, the effect of protein concentration on protein utilization is not considered. The results of the present work, as well as those obtained by other investigators, show that there is an inverse relationship between protein concentration and protein utilization. The net protein utilization (NPU) at 10% of protein-calories or the chemical score adjusted by the nitrogen digestibility can be applied when results are to be projected to national average diets, which have values ranging between 9 and 13%. When it is necessary to evaluate the diet of specific relatively homogeneous population groups, the recommended method should use the NPU determined or calculated in each meal considering the level of protein concentration of the diet as eaten (NPU op). This method takes into account the amino acid complementation in each meal. The data on which these conclusions are based have been presented and discussed.

A dietary survey was conducted in a department of El Salvador as part of an assessment of the nutritional status of preschool children. Intake of calories, protein and retinol equivalents were estimated using a 24-hour recall technique. The average daily energy intake for children 1-4 years old was 866 Kcal representing 60% of the 1973 level recommended by the Institute of Nutrition of Central America and Panama (INCAP), for this age group, and 76% of the recommended level on a body-weight basis. Average protein intake per child per day in the same age group was 31.3 g, which represents 110% of the recommended level for the age group, and 136% of the recommended level on a body weight basis. The estimated retinol equivalent intake was 36% of the recommended allowance. In general, the results of the present study were similar to those obtained in the study carried out in El Salvador by INCAP during the period September-November, 1965.

The purpose of the present study was to determine the protein quality and digestibility of shellfish commonly consumed in Chile, and to estimate its contribution to the protein needs of the Chilean population. The shellfish studied were chorito (Mytilus edulis chilensis), macha (Mesodesma donacium), loco (Concholepas concholepas), cholga (Aulacomya ater), erizo (Loxechinus albus) and almeja (no specific variety). The NPU method was used to determine protein quality. The percentage of protein adequacy for adult rations was calculated according to FAO/WHO 1973. The contribution of shellfish to the protein availability according to the family income of the Santiago population, was also calculated. Most of the shellfish presented NPU values of about 70; the lowest values were found for loco (54.9) and macha (63.3). The apparent and true digestibility gave an average of 83.6 and 90.4, respectively. The percentage of protein adequacy of habitual rations ranged between 27% (erizo) and 58% (loco). The availability of shellfish protein in relation to total protein increased from 0.4 to 2.5% when income increased. It is concluded therefore, that shellfish protein is, in general, of good quality. Nevertheless, it might be considered of poor influence insofar as fulfilling the protein needs of the population studied, whatever its socioeconomic level.

The protein-calorie (Po/o) and the protein value (NDpCalo/o) have been proposed as indices to evaluate the potentiality of diets to meet protein and calorie needs of a given population. The fat-calorie to protein-calorie ratio (G/P) is presented as a complementary index, considering the possibility that the values of Po/o and NDpCalo/o can be adequate but that the energy density of the diets is too low, as might be the case in many rural communities of the developing countries. On the basis of the evidence discussed in this paper, the G/P ratio estimated as adequate is 2.5, and values lower than 2 can be considered as nutritionally unacceptable.

A nutrition survey was carried out in a mountainous region southwest of Santiago, Dominican Republic, to determine the extent of malnutrition in the area and to obtain information regarding food beliefs and practices needed to design a viable nutrition program. A stratified cluster sampling technique was used to interview 295 mothers of preschool children and examine 448 of their children under five years of age. The incidence of moderate and severe malnutrition was less than expected. Only 12.3% of the children were less than or equal to 75% of the National Center for Health Statistics (NCHS) reference standard for weight/age; however, 6.5% were greater than 110% of the standard. Children from large, poor families were most vulnerable to growth retardation. Definite meal patterns were identified that included varied sources of cereal products and animal and mixed vegetable proteins. Milk and sausage consumption had a significant positive association with all three growth parameters. Suggestions were made for further research and program development.

The protein content (N x 6.25) of the seeds of Erythrina edulis (balú) varies between 18-21%; when the fraction corresponding to non-protein nitrogen is extracted with trichloroacetic acid (10%), this value decreases to 14-15%. Remarkable differences in the distribution of the protein fractions are observed when two schemes of extraction are assayed. The amino acid analysis shows that this legume has similar or higher amounts of most amino acids than those present in other leguminosae; the calculated chemical score and protein score show that methionine is the first limiting amino acid and tryptophan, the second. The protein efficiency ratio (PER) of thermically-treated flours has the highest value at 30 minutes of treatment (1.15).

Three experiments were conducted to study the possibility of improving the nutritive value of broad beans (Vicia faba, L.) in poultry diets. In the first experiment, raw and autoclaved (1.0 kg/cm2/15 min) beans, with and without antibiotic supplementation, were studied. The results after 21 days showed no significant differences among treatments in regard to body weight. In feed conversion, however, a significant difference was observed when diets prepared with raw beans were supplemented with 20 ppm of flavomycin. In the second experiment raw and autoclaved beans were supplemented with 0, 10, and 20 ppm of virginiamycin and 200 and 400 ppm of flavomycin to study the effect of these two antibiotics. After 28 days, the results indicated no significant differences with antibiotic supplementation in either raw or autoclaved beans. However, a significant difference (P < 0.05) in body weight was found when beans were autoclaved. In the third experiment, two levels, 31 and 76% of raw and autoclaved beans, were included in the chick diets. The results in body weight, after 28 days, did not show any significant differences between raw and autoclaved beans fed at a 31% level. With the 76% level the autoclaved treatment, however, induced a significantly higher body weight than the diets containing raw beans.

Data from a household expenditure survey of 1,200 Manaus families performed by the Amazonas State Government in 1973-74 are analyzed by income group. The per cent frequency of families buying different foods and the daily per capita consumption of each were calculated. The daily per capita intakes of energy, protein, vitamin A, thiamine, riboflavin, nicotinic acid, ascorbic acid, calcium, phosphorus, iron and zinc were estimated and their adequacy evaluated. In contrast to the south and northeast of Brazil, the main bulk of the diet was derived from cereals and fish. The quantities of eggs, meats, fruit and vegetables consumed per person, increased 50-100% as income improved, whereas fish consumption decreased 30%. The nutrients quantitatively most deficient were zinc, vitamin A, calcium, thiamine and riboflavin, with 60-80% of low and middle income families not achieving safe levels of intake for zinc and vitamin A. The beneficial effect of income on the adequacy of calcium, thiamine and riboflavin intake was quantitative. For zinc and vitamin A, increased income was associated with a qualitative improvement in the diet, principally due to the increased consumption of meat and liver. These results are discussed in relation to existing clinical evidence of deficiency states in the region.

A simple and practical methodology is proposed to define the "Family Food Basket", that must be based on the prevalent food situation of a country. At present, the "Family Food Basket" is an expression frequently used by government agencies (Ministries of Economics, Agriculture and Statistical Offices), because the money value estimation of the "Basket" is used as the basis for the establishment of minimum wages for the different socioeconomic groups. It is necessary, therefore, to determine the quantities of different foods that should be included as part of the diets so as to cover the nutritional requirements of the population. An explanation is also given here to show the differences between the "Food Basket" and the "Minimum Cost Recommended Diets", prepared in 1970 for the Central American countries. In order to explain the methodology, an example is given trying to define the "Family Food Basket of El Salvador" on the basis of available information gathered from food consumption surveys carried out at national level. Since a standardized methodology to obtain the actual food prices does not exist, some alternatives are given to estimate the money value of the "Family Food Basket".

The protein quality of soybean products was determined by a short nitrogen balance index (NBI) assay with 15 adult males. In the first study, a textured vegetable protein (TVP) was tested alone and in a 50:50 mixture with ground beef. Protein was fed at 0.2, 0.4 and 0.6 g/kg body weight/day with a constant energy intake. The protein quality (NBI) was then calculated by regression analysis of nitrogen absorbed to nitrogen retained. The NBI of beef (0.91) and of the mixture (0.87) were similar; however, the protein quality of TVP fed alone (0.77) was significantly lower. In the second study, carried out at an intake level of 0.6 g protein/kg/day, supplementation of the TVP with 0.5% DL-methionine improved nitrogen retention, but the values obtained did not reach statistical significance. Meat alone, or the 50:50 mixture fed at an equivalent protein intake, gave similar nitrogen retention values, both of which differed significantly from those obtained when TVP was fed alone. The addition of wheat gluten, used as a source of methionine, to the TVP: meat mixture, produced nitrogen retention values below those obtained with the 50:50 beef:TVP blend. Ten men participated in another trial, this time to determine the protein quality of a soybean protein isolate, which gave an NBI value of 0.91, indicating the high quality of the protein tested. Comparison of the protein quality values obtained by the short-term NBI assay revealed these were essentially the same as those reported by other workers using the conventional long-term approach.

A study was conducted to determine the protein requirements of normal young male subjects fed a model Mexican rural diet. The multiple-level nitrogen-balance technique was used in eight subjects; three of them were also studied when ingesting a milk diet. The mean requirements for the rural and milk diets were 112 and 105 mg N/kg body weight, respectively; accordingly, the amount of protein needed to cover the requirements of 97.5% of the population, calculated by method 3 of Rand, Scrimshaw and Young were 136 mg N/kg body weight for the rural diet, and 122 mg N/kg body weight for the milk diet. Interestingly, the NPU and the digestibility of the rural diet increased as the intake approached the requirement level.

Three experiments were carried out to determine the effects of autoclave cooking, extrusion and DL-methionine supplementation on the protein and energy value of cowpea. The two processes decreased the available lysine of cowpea from 6.3 to 5.7%. The starch content decreased from 50.7% in raw cowpea to 44.9% and 42.1% in cooked extruded cowpea, respectively. Cooking eliminated the trypsin inhibitor content of cowpea. Damaged starch increased from 0.3% in the raw cowpea, to 22.5% in cooked cowpea and to 30.5% in extruded cowpea. In the first experiment it was determined that the protein efficiency ratio (PER) in rats was not affected by cowpea processing (means = 1.17) and that DL-methionine supplementation increased (P less than 0.01) PER to 2.08. In the second experiment, it was established that energy digestibility of the diets used in the first experiment averaged 88.0% with no differences due to processing or supplementation. Digestible energy content (DE) was lower (P less than 0.01) in diets supplemented with DL-methionine (3.58, 3.56, 3.93) than in those without supplement (3.67, 3.93, 3.75). On the other hand, diets with extruded cowpea produced higher (P less than 0.01) DE (3.84 kcal/g) than diets with cooked cowpea (3.75 kcal/g). Classical (EM) and nitrogen corrected (EMn) metabolizable energy determined in chicks showed that both were higher (P less than 0.01) in cooked (3.01; 2.56 kcal/g) and extruded (3.16; 2.76 kcal/g) than in raw cowpeas (1.86; 1.81 kcal/g).

The competition between cereals and root crops as CARICOM staples is described. The move to substitute locally grown food for imported wheat is shown to favor root crop development in the region. Against this background, traditional nutrition-prompted objections to wheat substitution by root crops are examined. Evidence is cited to show the essential adequacy of protein in root crops, except plantain and cassava and for all humans except perhaps some infants. The low protein in cassava and plantain, it is proposed, can be easily overcome in the process of local root crop development. Finally, it is argued that there exists the potential to obtain cheap calories from root crops. This and the generation of economic activity among small farmers, concomitant with root crop development, are seen as possible indicators of good nutrition for the region in the future.

This paper proposes a new approach to estimate the protein needs of a population; recommendations are also made on the protein intake of adults fed diets based on rice and beans. For this purpose, the nitrogen balance data previously reported for 40 adult human subjects who had participated in 160 nitrogen balance periods fed diets based on rice and beans, with and without animal protein and/or energy supplementation were used. The proposed method is based on the curvilinear response between nitrogen intake and its nitrogen balance. The second degree equation describing the relationship between nitrogen balance and intake is calculated. Using the mathematical concept of the first and second derivatives, the point of inflexion is obtained, and interpreted as that condition wherein the individual utilizes with maximum efficacy the ingested nitrogen; nitrogen ingestion, which corresponds to that point, is therefore taken as the dietary nitrogen recommendation for the individual. When the values obtained by means of the quadratic equation are compared to those obtained by the traditional linear equation, values were found to be statistically equal (p less than 0.05) for both calculation methods. The recommended protein intake of an adult population fed a diet based on rice and beans was 0.80 and 0.77 g/kg/day for the quadratic approach, and for the conventional method, respectively. When this diet was supplemented with 10% milk protein and with the same energy level, the calculated values were 0.64 and 0.71 g protein/kg/day for both methods, in this same order. The essential amino acid intake and absorption values were also calculated from the protein levels recommended by both methods to be in nitrogen balance, from a diet based on rice and beans. Findings revealed, in all cases, that the intakes of each and all essential amino acids met those levels indicated by FAO/WHO, with the exception of isoleucine and the sulphur-containing amino acids, which apparently limit the quality of the diet.

Food patterns, and energy and nutrient intake of a sample of rural and urban families in the Peruvian Andes are analyzed and compared with requirements and recommended figures of nutrient allowances. It is concluded that, with the exception of vitamin A, there is very little nutrient deficiency where calorie requirements are met. About half the population in the region suffers from some degree of calorie deficiency in the sense that the total quantity of food available to the family is insufficient to satisfy energy needs of all family members. The incidence of calorie deficiency is about equally distributed between rural and urban areas and there is strong evidence that calorie intake is positively correlated with the proportion of home-produced to total (home-produced and purchased) food.

A screening method for the characterization and differentiation of proteinaceous samples and amino acid mixtures was applied to protein foods (4 protein-rich mixtures, one product sold as dietary supplement, and 3 raw materials of frequent use in the preparation of these products). Graphic profiles which describe the relative amounts of amino acid groups in the samples were obtained and subjected to statistical analysis. According to a previously established criterion of identity or difference, the correlation coefficients showed that at least 90% of the comparisons dealt with different samples. The method is proposed as a valuable tool for the quality control of protein-rich foods and their raw materials.

A wide variety of factors can influence the development, production and introduction of high-quality protein foods in a given country. Such factors can be grouped in three main areas: I. Factors depending upon the country itself. II. Factors related with the identity of the food and III. Factors inherent to the consumer. The role of the food industry and of the government are discussed in area I, and such aspects as improvement of staples, availability of raw materials, health programs and energy crisis are briefly commented. Area II covers product identity in relation to used ingredients. Nutritional quality and requirements as well as the danger of increasing the price of the product after being in the market are briefly discussed. The consumer's attitude, preferences and personal reactions towards the presentation of the food are covered in area III. Also marketing approach, promotion, labels and possible influence of the name are discussed. The launching of "incaparina" in Venezuela in 1964 and the reasons for its failure are commented from the different points of view covered in the above sections.