No abstract

The glycaemic index (GI) of commonly consumed bakery products supplemented with increasing levels of coconut (Cocos nucifera) flour was determined in ten normal and ten diabetic subjects. Using a randomized crossover design, the control and test foods were fed in random order on separate occasions after an overnight fast. Blood samples were collected through finger prick before and after feeding and were analysed for glucose levels using a clinical chemistry analyser. The significantly low-GI (, 60) foods investigated were: macaroons (GI 45·7 (SEM 3·0)) and carrot cake (GI 51·8 (SEM 3·3)), with 200-250 g coconut flour/kg (P,0·05). The test foods with 150 g coconut flour/kg had GI ranging from 61·3 to 71·4. Among the test foods, pan de sal (GI 87·2 (SEM 5·5)) and multigrain loaf (GI 85·2 (SEM 6·8)) gave significantly higher GI with 50 and 100 g coconut flour/kg respectively (P, 0·05). On the other hand, granola bar and cinnamon bread with 50 and 100 g coconut flour/kg respectively gave a GI ranging from 62·7 to 71·6 and did not differ significantly from the test foods with 150 g coconut flour/kg (P, 0·05). A very strong negative correlation (r 2 0·85, n 11, P, 0·005) was observed between the GI and dietary fibre content of the test foods supplemented with coconut flour. In conclusion, the GI of coconut flour-supplemented foods decreased with increasing levels of coconut flour and this may be due to its high dietary fibre content. The results of the present study may form a scientific basis for the development of coconut flour as a functional food. However, the fat content of coconut flour-supplemented food should always be considered to optimize the functionality of coconut fibre in the proper control and management of diabetes mellitus.

This study investigated the effect of coconut flakes on serum cholesterol levels of humans with moderately raised serum cholesterol in 21 subjects. The serum total cholesterol of subjects differed and ranged from 259 to 283 mg/dL. The study was conducted in a double-blind randomized crossover design on a 14-week period, consisting of four 2-week experimental periods, with each experimental period separated by a 2-week washout period. The test foods were as follows: corn flakes as the control food, oat bran flakes as the reference food, and corn flakes with 15% and 25% dietary fiber from coconut flakes (made from coconut flour production). Results showed a significant percent reduction in serum total and low-density lipoprotein (LDL) cholesterol (in mg/dL) for all test foods, except for corn flakes, as follows: oat bran flakes, 8.4 +/- 1.4 and 8.8 +/- 6.0, respectively; 15% coconut flakes, 6.9 +/- 1.1 and 11.0 +/- 4.0, respectively; and 25% coconut flakes, 10.8 +/- 1.3 and 9.2 +/- 5.4, respectively. Serum triglycerides were significantly reduced for all test foods: corn flakes, 14.5 +/- 6.3%; oat bran flakes, 22.7 +/- 2.9%; 15% coconut flakes, 19.3 +/- 5.7%; and 25% coconut flakes, 21.8 +/- 6.0%. Only 60% of the subjects were considered for serum triglycerides reduction (serum triglycerides >170 mg/dL). In conclusion, both 15% and 25% coconut flakes reduced serum total and LDL cholesterol and serum triglycerides of humans with moderately raised serum cholesterol levels. Coconut flour is a good source of both soluble and insoluble dietary fiber, and both types of fiber may have significant role in the reduction of the above lipid biomarker. To our knowledge, this is the first study conducted to show a relationship between dietary fiber from a coconut by-product and a lipid biomarker. Results from this study serves as a good basis in the development of coconut flakes/flour as a functional food, justifying the increased production of coconut and coconut by-products.

Iron absorption from rice fortified with different iron fortificants, e.g., ferrous sulfate (FeS0 4), sodium iron EDTA (NaFeEDTA), ferrous fumarate (FeFum), and ferrous bisglycinate (FeBis) was determined using an in vitro enzymatic digestion method simulating conditions in the small intestine and an in vivo method using radioisotope techniques. The in vitro method showed that the percentage of dialyzable iron from NaFeEDTA (15.7 ± 0.9) and FeS0 4-fortified rice (13.2 ± 1.5) was significantly greater than that from FeFum (6.4 ± 0.6; p < .05) and FeBis fortified rice (3.3 ± 0.8; p < .05). Iron absorption in vivo was investigated from FeS0 4 and NaFeEDTA fortified rice with and without fish and vegetables in 10 borderline irondeficient subjects. Iron absorption (mg) from NaFeEDTA fortified rice (0.44 ± 0.11) was significantly greater than from FeS0 4-fortified rice (0.22 ± 0.05; p < .05) and the unfortified rice (0.17 ± 0.02; p < .05). Iron absorption (mg) from a meal consisting of iron-fortified rice, fish, and vegetables was significantly greater from NaFeEDTA (0.88 ± 0.24) and FeS0 4 (0.67 ± 0.10)-fortified rice than from the unfortified rice (0.41 ± 0.08; p < .05). This study concluded that both NaFeEDTA and FeS04 are effective iron fortificants for rice. The binder used in the study may have a significant role in the release of iron from iron-fortified rice for absorption. Further studies on the use of other binders to maximize iron release and minimize iron loss during cooking should be conducted to improve iron absorption from the fortified rice/ricefish-vegetable meals. Results from this study can be used as a basis for food iron fortification programs as well as in the establishment of recommended dietary allowances for iron among Filipinos.

No abstract