The between-laboratory SD of the GI values is approximately 9. Standardized data analysis and low within-subject variation (refCV<30%) are required for accuracy. The results suggest that common misconceptions exist about which factors do and do not need to be controlled to improve precision. Controlled studies and cost-benefit analyses are needed to optimize GI methodology. The trial was registered at clinicaltrials.gov as NCT00260858.

a b s t r a c tThe purpose of this study was to determine the effects of Pleurotus sajor-caju (PSC) powder addition at 0, 4, 8 and 12% levels on the nutritional values, pasting properties, thermal characteristics, microstructure, in vitro starch digestibility, in vivo glycaemic index (GI) and sensorial properties of biscuits. Elevated incorporation levels of PSC powder increased the dietary fibre (DF) content and reduced the pasting viscosities and starch gelatinisation enthalpy value of biscuits.The addition of DF-rich PSC powder also interfered with the integrity of the starch granules by reducing the sizes and inducing the uneven spherical shapes of the starch granules, which, in turn, resulted in reduced starch susceptibility to digestive enzymes. The restriction starch hydrolysis rate markedly reduced the GI of biscuits.The incorporation of 8% PSC powder in biscuits (GI = 49) could be an effective way of developing a nutritious and low-GI biscuit without jeopardizing its desirable sensorial properties.

These results suggest that replacing 10 % of refined wheat flour with fenugreek seed powder significantly reduces the glycemic response and the GI of buns and flatbreads. Thus, fenugreek powder may be a useful functional ingredient to reduce postprandial glycemia.

Aim:To determine the glycemic index (GI) of Malaysian wild honey and Australian honey. Methods: Eight healthy volunteers (5 men and 3 women, aged 24 -44 y, with normal BMI) were served 50 g carbohydrate portions of two varieties of honey or the reference food (glucose, tested 3 times), on separate occasions. Capillary blood glucose was measured fasting and at 15, 30, 45, 60, 90 and 120 min after the start of the test meals. The GI was calculated by expressing each subject's incremental area under the blood glucose curve (AUC) after honey as a percentage of his or her mean AUC after glucose.Results: The results showed that the mean AUC of the Malaysian and Australian honeys, 174 ± 19 and 158 ± 16 mmol×min/l, respectively, did not differ from each other but were significantly less than that after glucose, 259 ± 15 mmol×min/l (P < 0.001). The mean GI of Malaysian wild honey, 65 ± 7, did not differ from that of Australian honey, 59 ± 5, but both were significantly less than the GI of glucose, 100 (P < 0.001).Conclusions: We conclude that both Malaysian wild honey (GI = 65 ± 7) and Australian honey (GI = 59 ± 5) are intermediate GI foods.

This study determined the effects of fenugreek on postprandial plasma glucose (PPG) and satiety among overweight and obese individuals. Fourteen subjects were studied in the morning after overnight fasts on four separate occasions. Glycaemic responses elicited by 50 g carbohydrate portions of white bread and jam with or without 5.5 g of fenugreek and fried rice with or without 5.5 g fenugreek were determined over 2 h. The primary endpoint was the incremental area under the plasma glucose response curve (IAUC). Adding fenugreek to both foods significantly reduced the IAUC compared to the food alone: white bread and jam, 180 ± 22 versus 271 ± 23 mmol × min/L (P = 0.001); fried rice, 176 ± 20 versus 249 ± 25 mmol × min/L (P = 0.001). Fenugreek also significantly reduced the area under the satiety curve for white bread with jam (134 ± 27 versus 232 ± 33 mm × hr, P = 0.01) and fried rice (280 ± 37 versus 379 ± 36 mm × hr, P = 0.01). It is concluded that fenugreek significantly decreased the PPG response and increased satiety among overweight and obese individuals.

Aims: Our purpose was to determine whether the glycemic index (GI) of individual foods applies to mixed meals. Methods: The glycemic responses elicited by portions of 4 individual foods with 25 g of available carbohydrate when served alone (rice, lacy pancake, flatbread and noodles) and when made into typical Malaysian mixed meals (coconut milk rice, lacy pancake with chicken curry, flatbread with dhal curry and fried noodles) were measured in 10 subjects with type 2 diabetes. To allow calculation of the GI of the foods and the relative glycemic responses of the mixed meals, each subject also tested 25 g of glucose 3 times. Capillary blood glucose was measured at 30-min intervals for 180 min after consuming each test meal. Results: The mean ± SEM incremental area under the curve (AUC) after flatbread (345 ± 26 mmol × min/l) was significantly greater than after rice (238 ± 35) and lacy pancake (235 ± 31, p < 0.05), with noodles being intermediate (294 ± 35). The AUC after the flatbread with dhal curry (341 ± 49), coconut milk rice (238 ± 39) and fried noodle (272 ± 42) mixed meals were similar to those after the individual foods, but the AUC after the lacy pancake with chicken curry mixed meal (388 ± 52) was significantly greater than after the individual food item (p < 0.01). Conclusions: The results support the utility of the GI of individual foods such as rice, flatbread and noodles when applied to mixed meals. The reason for the higher response after the lacy pancake mixed meal compared to the individual food is not clear and may warrant further research.

Dietary fibre content is a known factor that can affect the postprandial glycemic responses of a food and meal. Cornlettes vegetable which is rich in dietary fibre has been studied for its potential in lowering the peak glycemic responses of biscuits and muffins. Cornlettes was processed into powder and formulated into four formulations of selected bakery products. The glycemic responses produced by portions of the biscuits and muffins containing 25 g available carbohydrate were measured in 11 healthy volunteers. The incremental area under curve (AUC) of control biscuits was greater (81 ± 11 mmol × min/l) than cornlettes powder (CP) added biscuit (63 ± 12 mmol × min/l). Likewise, the AUC of control muffins was higher (88 ± 13 mmol × min/l) than CP-added muffins (74 ± 12 mmol × min/l). Control biscuits had an intermediate GI value of 61 while CP-added biscuits had a low GI value of 46. Both control and CP-added muffins recorded intermediate GI values (58 and 57, respectively). It is concluded that CP can be incorporated in selected bakery products as a potential ingredient to help lower the peak rise of postprandial glycemic responses.

The effects of partial replacement of wheat flour with young corn ear (YCE) on sensory properties and glycemic index (GI) of chiffon cake were investigated. Dried YCE was processed into powdered form and added in chiffon cake formulations to replace wheat flour partially at concentrations of 0 (control), 10%, 20% and 30%. Protein, ash and dietary fibre contents of chiffon cake added with YCE powder were increased in line with the levels of YCE used. Even though protein content of YCE-based cakes increased in line (13.3% to 15.7%) with the levels of YCE (10% to 30%), but there was no significant difference compared to control. Sensory evaluation results indicate that partial replacement of wheat flour with up to 10% is satisfactory as compared to other levels of wheat flour replacement. Interestingly, addition of YCE at 10% to partially replace wheat flour resulted in reduction of postprandial blood glucose response. The GI value for chiffon cake added with YCE was 49 lower than control cake which recorded GI value at 60. In conclusion, novel food ingredient of YCE can be incorporated in selected bakery products to enhance nutritional composition while at the same time help in reducing the GI value. Further investigation on the addition of YCE into other bakery products in relation to nutrition and glycemic response effects can also be explored.