Enrique Yáñez

Chemical and nutritional evaluation of sweet lupines.

Sweet lupines are presently being cultivated at the Experimental Station in Gorbea (Chile). Four cultivars, Lupinus albus cv Astra, L. albus cv Multolupa, Lupinus luteus cv Aurea and Lupinus angustifolius, were examined for the chemical composition of whole and dehulled seeds and testa. Whole seeds contain 34-35% protein. The varieties of L. albus contain 13% oil. L. luteus and L. angustifolius contain about 5% ether extract. Crude fiber ranged from 11 to 17% in the whole seed. Unsaturated fatty acids, especially oleic and linoleic, make up about 80% of total fatty acids. The alkaloid content of the seed was 0.02%. The amino acid composition of the protein indicated that the main deficiency corresponds to the sulfur-containing amino acids, i.e. methionine + cystine. The protein efficiency ratio values for L. albus cv Multolupa was 1.08 and 2.50 for casein. Supplementation with DL-methionine at 0.1, 0.2, 0.3 and 0.4% of the diet significantly increased the basal value from 1.08 to 2.14, for the supplemented diet with 0.1% (p less than 0.01). Higher levels of supplementation did not cause significant increases in the protein efficiency ratio. Apparent protein digestibility for the rat was 75% for unsupplemented lupine. This value increased to about 79% (p less than 0.01) for the supplemented diets (casein 88.7%).

Effect of processing on some chemical and nutritional characteristics of pre-cooked and dehydrated legumes

The effect of processing on chemical composition and protein quality of three legumes was studied. The species analyzed were beans (Phaseolus vulgaris), Tórtola and Coscorrón varieties; lentils (Lens esculenta), Laird variety; and chick peas (Cicer arietinum), California-INIA variety. The legumes were soaked in a solution of Na2 EDTA at 0.03% for 16 h and cooked for a predetermined period for each species. They were dried in a tray drier with cross currents of air flowing at a speed of 10 m/min until the residual mositure content was 8%. The water activity in the resulting products ranged from 0.574 to 0.587, thus completely assurring no microbial activity. No important changes were observed in the legumes protein, fat, or fibre contents after processing. The soaking solution was effective in reducing the phytic acid content from 2.99 to 1.64 mg/100 g in the Tórtola beans, which had the highest acid value prior processing. In all the species the heat treatment reduced the activity of the trypsin inhibitors by at least 50%. Cooking and drying significantly increased protein digestibility in all the legumes studied, with chick peas showing the most dramatic increase: from 54.7% pre-processing to 94.9% post-processing. With regard to Net Protein Ratio (NPR), chick peas had a value of 4.03, followed by Tórtola beans (3.29), Coscorrón (3.09) and lentils (2.61). The NPR value for the casein diet was 4.20.

Safety evaluation of sweet lupine (Lupinus albus cv. Multolupa). II. Nine-month feeding and multigeneration study in rats.

Sweet lupine Lupinus albus cv. Multolupa) flour containing 41.7% protein and 0.025% lupanine was fed for 9 months to two generations of rats (F1 and F2) at a level that provided 20% dietary protein. The diets were supplemented with 0.2% DL-methionine. The control diet provided the same dietary protein level from defatted soya-bean flour, fish meal and dried skimmed milk. The lupine diet had no effect on the general condition, mortality or behaviour of the animals. The growth rate of males fed sweet lupine was significantly higher than that of the controls. Haematological parameters and tests of liver function were normal in all treatment groups. At autopsy there were no significant changes in the weight of the heart, kidney, spleen, brain and gonads. However, the relative weight of the liver of lupine-fed rats was significantly lower than that in the controls. The histology of the liver, like that of the other organs examined, was normal. The reproduction study did not reveal any adverse effect on fertility or lactation that could be attributed to ingestion of sweet lupine. This investigation did not disclose any deleterious effects through two generations of rats that were fed sweet lupine at a level that provided 20% dietary protein for 9 months.

Obligatory urinary and faecal nitrogen losses in young Chilean men given two levels of dietary energy intake

1. The obligatory nitrogen losses were measured in young adult males of the low socio-economic group, consuming an N-free diet at 192 kJ (46 kcal)/kg per d from day 1 to 10 and 243 kJ (58 kcal)/kg per d from day 11 to 18. 2. All subjects, except one, lost weight compatible with N loss. 3. A kinetic evaluation of the results showed that the asymptotically derived urinary N loss after stability had been reached was 35.8 mg N/kg per d. The mean time to stability was 6.5 d. The subjects showed a trend toward decline in N loss while consuming the high-energy N-free diet. 4. The obligatory faecal N loss for days 1-10 was 16.1 mg N/kg per d and 8 mg N/kg per d for days 11-18. 5. Based on the factorial approach the total obligatory N loss of our subjects, for the initial 10 d, was 57.5 mg N/kg per d.

Nutritive value evaluated on rats of new cultivars of common beans (Phaseolus vulgaris) released in Chile

Five new cultivars of common beans (Phaseolus vulgaris) recently released were analyzed for their proximate chemical composition and protein biological quality. The crude protein content in these cultivars ranged from 21.9 percent in cultivar Arroz 3 to 26.9 percent in cultivar Tórtola Diana (dry matter basis). Rats fed cultivar Tórtola INIA gained more weight, had a higher protein intake and registered higher PER and NPR than Tórtola corriente. On the other hand, rats consuming cultivars Arroz 3 and Fleetwood had lower weight gain, lower protein intake and lower PER and NPR than cultivar Coscorrón corriente. However, all these cultivars have a relatively good protein value as compared to other plant protein sources.

Protein-rich mixtures for human consumption based on fish flour, sunflower presscake meal, dried skim milk and wheat flour

I. The quality of the protein in five high-protein mixtures intended for human consumption and made from materials that are available in Chile is reported. 2. The ingredients were fish flour, bread, wheat (Triticum sutivum Lam.) flour, roasted whole wheat flour, a wheat flour made from a variety of dururn wheat (T . durum Desf.), skim milk and sunflower presscake, mixed in different proportions. 3. The net protein utilization when fed to rats in diets at the 10 yo level of protein calories gave values in the range 66-76, which compare well with that (67), found for Incaparina, an all-vegetable mixture produced by the INCAP Group and used in Colombia, and are higher than the values (55 and 56) obtained for Peruvitas, which are mixtures made up basically from cottonseed and quinoa reinforced with dried skim milk. 4. The protein values of the mixtures, expressed as net dietary protein calories yo, were calculated from their biologically determined net protein utilization (operative), and gave values that ranged from 10.5 to 12.8, which are higher than the recommended values in diets for infants and toddlers.

Nutritional Problems in the Weaning Period with Special Reference to Chile

There is wide agreement among pediatricians and nutritionists that human breast milk represents the optimal food for the human infant, but the substitution of breast feeding continues, often with dire consequences. The American Academy of Pediatrics has stated that “breast feeding is recommended for all full-term and vigorous preterm infants because human milk is nutritionally sound and because breast feeding tends to facilitate a close mother/child relationship”. Despite this and many other official statements there is a strong trend towards a short breast feeding period. At best, only 30 percent of American children are breast-fed for any length of time and women around the world seem to be nursing for less and less time. In the United States only 25 percent of infants are breast-fed at age one week and this figure declines to 5 percent at age 6 months. The decline in breast feeding has been marked and progressive during the last decades in industrialized countries. This fact is clearly illustrated by data from Sweden collected from 1944 to 1970.

69 NUTRITIVE VALUE OF WHEAT FLOUR SUPPLEMENTED WITH SWEET LUPINE (L. albus var. multolupa)

Genetic varieties of sweet lupine with low alkaloid content are being developed in Chile. These legumes constitute an interesting source of protein for human feeding. In this investigation the chemical composition and biological quality of lupine flour, measured as PER in the rat, were determined. The effect of supplementation upon the biological quality of wheat flour with 5,10,15 and 20% of lupine was also studied. Lupine flour contained 36.4 % protein (N×6.25), 11.5 % lipids and 12% crude fiber. PER was 1.13 cpmpared with 2.64 for casein, used as a reference standard. On supplementation wheat flour improved the quantity and quality of its protein. The protein content increased from 9.3% to 13.7% with 20% of lupine and PER from 0.70 to 1.21, 1.33, 1.65 and 1.84 for the 5,10,15 and 20% lupine levels respectively. These results support the possibility of increasing the biological value of wheat by supplementation with lupine protein, thus permitting the improvement of wheat-based diets consumed by large segments of human population.