The Glycemic Potential of White and Red Rice Affected by Oil Type and Time of Addition.

UNLABELLED: Limited research exists on how different oil types and time of addition affect starch digestibility of rice. This study aimed to assess the starch digestibility of white and red rice prepared with 2 oil types: vegetable oil (unsaturated fat) and ghee (clarified butter, saturated fat) added at 3 different time points during the cooking process ("before": frying raw rice in oil before boiling, "during": adding oil during boiling, and "after": stir-frying cooked rice in oil). Red rice produced a slower digestion rate than white rice. White rice digestibility was not affected by oil type, but was affected by addition time of oil. Adding oil "after" (stir-frying) to white or red rice resulted in higher slowly digestible starch. Red rice cooked using ghee showed the lowest amount of glucose release during in vitro digestion. The addition of ghee "during" (that is boiling with ghee) or "before" (that is frying rice raw with ghee then boiling) cooking showed potential for attenuating the postprandial glycemic response and increasing resistant starch content. This is the first report to show healthier ways of preparing rice. White rice with oil added "after" (stir-fried) may provide a source of sustained glucose and stabilize blood glucose levels. Boiling red rice with ghee or cooking red rice with ghee pilaf-style may provide beneficial effects on postprandial blood glucose and insulin concentrations, and improve colonic health. The encouraging results of the present study justify extending it to an in vivo investigation to conclusively determine the effect of time of addition of fat when rice is cooked on blood glucose homeostasis. PRACTICAL APPLICATION: Rice is a predominant source of energy in most of Asia with excessive consumption of rice being implicated in the rise of type 2 diabetes. Stir-frying white rice can be a source of sustained glucose and provide a stabilizing effect on blood glucose levels. Boiling red rice with ghee or cooking red rice with ghee pilaf-style may provide beneficial effects on postprandial blood glucose and insulin concentrations. This suggests how a single technique of adding fat in the cooking of rice at certain time points may be a useful method in providing taste and lowering glycemia.

The impact of a low glycemic index (GI) breakfast and snack on daily blood glucose profiles and food intake in young Chinese adult males.

OBJECTIVE: Low glycemic index (GI) foods have been suggested to minimize large fluctuations in blood glucose levels and reduce food intake. However, the majority of studies have been conducted on Caucasian populations with limited data on Asians. The objective of this study was to investigate how the provision of a low GI breakfast and afternoon snack affected daily blood glucose profiles and food intake. MATERIALS AND METHODS: In a randomized, controlled crossover non blind design, 11 healthy Chinese male adults (body mass index 22.4 ± 1.3 kg m-2) attended two sessions where they consumed either a high or low GI breakfast and afternoon snack, and a standardized buffet lunch. Daily changes in glycemic response (GR) were measured using the Medtronic MiniMed (Northridge, CA) iPro™2 continuous glucose monitoring system (CGMS). The GR was further calculated to obtain the incremental area under the curve (IAUC). Glycemic variability was calculated as mean amplitude of glycemic excursion (MAGE) and energy intake (kcal) was measured quantitatively at the buffet lunch. RESULTS: Compared to the high GI intervention, the low GI intervention significantly reduced the GR following breakfast (p = 0.02), lunch (p = 0.02) and dinner (p = 0.05). The low GI treatment showed a reduction in daily AUC (p = 0.03). There was a significant reduction in IAUC after a low GI breakfast compared to the high GI breakfast (p = 0.03). The low GI breakfast resulted in a significantly lower food intake at lunch and a resulting decreased energy intake of 285 kcal (p = 0.02). The MAGE was significantly lower during the entire low GI treatment (p = 0.03). CONCLUSIONS: Consumption of a low GI breakfast and afternoon snack was capable of attenuating 24-h blood glucose profiles, minimize glycemic excursions and reduce food intake in healthy Asian males. This simple dietary intervention may be an acceptable approach in improving overall glycemia and energy balance in Asians. CLINICAL TRIAL REGISTRATION NUMBER: NCT02340507.

Application of Hazard Analysis Critical Control Point in the local manufacture of ready-to-use therapeutic foods (RUTFs).

The local manufacture of ready-to-use therapeutic foods (RUTFs) is increasing, and there is a need to develop methods to ensure their safe production. We propose the application of Hazard Analysis Critical Control Point (HACCP) principles to achieve this goal. The basic principles of HACCP in the production of RUTFs are outlined. It is concluded that the implementation of an HACCP system in the manufacture of RUTFs is not only feasible but also attainable. The introduction of good manufacturing practices, coupled with an effective HACCP system, will ensure that RUTFs are produced in a cost-effective, safe, and hygienic manner.

The influence of saturated fatty acids on complex index and in vitro digestibility of rice starch.

In Asia, rice and rice products are the main sources of carbohydrate contributing to both dietary energy and glycaemic load. It is known that complexation of starch with lipids could potentially reduce the availability of starch to enzymatic degradation. The aim of this study was to investigate the effect of capric, lauric, myristic, palmitic and stearic acids, ranging from 0 to 2 mmol/g starch, on complexing index and in vitro digestibility of gelatinized rice starch. The results revealed that the ability of rice starch to complex with saturated fatty acids increased with increasing concentration; but reduced with increasing lipid chain length. The complexation of rice starch with capric, lauric, myristic and stearic acids did not reduce the in vitro starch digestibility, except rice starch-palmitic acid complexes.

A comparative evaluation of the glycaemic potential of commercial breads consumed in South East Asia.

Bread has become a widely consumed staple food in South-east Asia. However, there is very little data on the glycaemic potential of local commercial breads. The objective of this study was to comparatively assess the glycaemic potential of some commonly consumed commercial breads using a validated in vitro model. Sixteen types of breads representing the most popular brands and types were evaluated. The results showed that white and enriched white breads had a greater glycaemic potential than wholemeal breads (rapidly digestible starch (RDS) content >450 mg of glucose/g of sample). The lowest glycaemic potential was observed for wholegrain breads (RDS content < 375 mg of glucose/g of sample). The glycaemic impact of some specialty breads such as pandan bread, milk bread and corn loaf was also examined. Whist the data show that South-east Asian breads have notably differential effects on glycaemia, it highlights the need to formulate Asian dietary guidelines for bread which will enable better food choice and glycaemic control.

Polydextrose: its impact on short-term food intake and subjective feelings of satiety in males-a randomized controlled cross-over study.

PURPOSE: Polydextrose is a low-calorie highly branched-chain glucose polymer that is poorly digested in the upper gastrointestinal tract and therefore demonstrates fibre-like properties. Fibre has been shown to increase satiety and possibly reduce food intake. Therefore, the objective of the current study was to examine the effects of polydextrose on short-term satiety and energy intake. METHODS: In a repeated-measures randomized blind cross-over design, 26 healthy males consumed a 400-g fruit smoothie containing 12 g (3 %) of polydextrose, and a buffet lunch 60 min after the smoothie. Motivational ratings for satiety and palatability and lunch energy intake were measured. The effects of the polydextrose-containing smoothie were compared against a polydextrose-free control smoothie. RESULTS: Polydextrose did not significantly alter the taste and palatability of the fruit smoothie. Consuming the polydextrose-containing smoothie resulted in a significantly lower energy intake at lunch (102 kcal less) compared to the control. CONCLUSION: Polydextrose may be a good fortificant for reducing short-term food intake.

The addition of raspberries and blueberries to a starch-based food does not alter the glycaemic response.

It is now known that health benefits associated with diets rich in fruit and vegetables may be partly derived from intake of polyphenols. Berry polyphenols may influence carbohydrate metabolism and absorption and hence postprandial glycaemia. To date, studies related to polyphenol effects on the glycaemic response have been completed only in liquids using either monosaccharides or disaccharides. It remains to be determined whether berries known to be rich in polyphenols can reduce the glycaemic response (GR) to a solid polysaccharide meal. The aim of the present study was to investigate whether berries alter postprandial hyperglycaemia and consequently the GR to a starchy food. Blood glucose was tested on seven occasions, on three occasions using a reference food and on four occasions using pancakes supplemented with either raspberries or blueberries or control pancakes containing similar amounts of fructose and glucose. Results showed that there were no differences in GR (blueberry 51·3 (SEM 5·7); raspberry 54·7 (SEM 5·6); blueberry control 43·9 (SEM 4·2); raspberry control 41·8 (SEM 6·4)), GR area under the curve or satiety index between any of the tests. The present study indicates that the ability of berries to reduce blood glucose from starch-based foods is unsubstantiated.

Does prolonged chewing reduce food intake? Fletcherism revisited.

Horace Fletcher (1849-1919) spread his doctrine to chew each mouthful thoroughly in order to prevent gaining weight. We sought to test this idea by manipulating chewing instructions whilst using electromyography to monitor chewing behaviour. Comparing 35 with 10 chews per mouthful, we showed that higher chewing counts reduced food intake despite increasing chewing speed, and despite doubling meal duration for achieving a subjective reference point for feeling 'comfortably full'. Although limited by a low sample size, our preliminary findings confirm Mr. Fletcher's doctrine, and provide a basis for further research in this area. Outcomes and implications are discussed.

Glycemic response and glycemic index of semolina spaghetti enriched with barley ß-glucan.

OBJECTIVE: The postprandial glycemic response and glycemic index (GI) of spaghetti made with semolina and the addition of two ß-glucan barley concentrates, Glucagel (GG) and Barley Balance (BB), was studied. METHODS: For each type of ß-glucan concentrate, six spaghetti samples containing increasing percentages (0%, 2%, 4%, 6%, 8%, and 10%) of ß-glucan were made. Nine healthy subjects were recruited for measuring the glycemic response and GI. Subjects were served portions of the test foods (50 g of available carbohydrates) and a reference food (50 g of glucose) on separate occasions. Capillary blood glucose was measured up to 120 min after consuming the spaghetti. The total glycemic response was calculated geometrically as the incremental areas under the curve (IAUC) using the trapezoid rule. The GI was calculated geometrically by expressing the IAUC for the test food as a percentage of each subject's average IAUC for the glucose. RESULTS: The IAUC for spaghetti with and without ß-glucan was significantly less compared with glucose. The GG spaghetti had IAUC values similar to the spaghetti without ß-glucan concentrate. The BB spaghetti showed IAUC values lower than that of the spaghetti without ß-glucan. In particular, the spaghetti with 10% BB had an IAUC 52% lower (P ≤ 0.017) than the spaghetti with ß-glucan. The GI values for spaghetti with GG were statistically similar to the control. The GI of BB spaghetti decreased with increasing BB concentrations. In particular, the GI of 10% BB spaghetti was 54% lower (P ≤0.02; GI = 29) than that of the control (GI = 64). CONCLUSION: The BB concentrate significantly decreases the IAUC and GI of spaghetti at a dose of 10%. GI at the same concentrations does not.

Liquid and solid carbohydrate foods: comparative effects on glycemic and insulin responses, and satiety.

It is speculated that the physical form (liquid or solid) of the food substrate has an independent effect on the body's satiety mechanisms. Using a balanced and controlled design, the objective of the present study was to determine the glycemic response (GR), insulin response (IR) and subjective feelings of satiety to two solid (rice [BR] and spaghetti) and two liquid (orange juice and a sugar-sweetened fruit drink [SSD]) foods. Ten healthy participants consumed volume (576 ml) and carbohydrate (50 g) matched portions of the above test foods following a 12-h fast. Blood samples were obtained for the ensuing 120 min for glucose and insulin determination. The subjects also completed visual analog scales (VAS) providing data on subjective feelings of hunger, fullness and satiety. Although there were some significant differences in the total incremental areas under the curve for the GR and IR to liquids and solids, there were notable distinctions in the pattern of the response curves. The BR and SSD elicited significantly different levels of subjective hunger, fullness and satiety. The VAS ratings for all four treatments were at or below baseline by 30 min post-consumption. There were no associations between the GR/IR and VAS ratings. Although the GR and IR were not different between liquids and solids, their differential response patterns could have an impact on satiety and merits further investigation.

Degree of habitual mastication seems to contribute to interindividual variations in the glycemic response to rice but not to spaghetti.

Previous work by our group showed that the degree of particle breakdown of rice during mastication affects in vitro glycemic potency. The objective of this study was to confirm these in vitro findings in an in vivo model. We hypothesized that the degree of habitual mastication will influence individuals' in vivo blood glucose response (glycemic response, or GR) to carbohydrate foods. Eleven participants came in on six nonconsecutive days to the laboratory and evaluated 2 test foods (rice and spaghetti). Their GR was measured for the subsequent 120 minutes. Mastication parameters were determined using surface electrode electromyography. The particle size distribution of individuals' masticated food was also determined. The intraindividual number of chews per mouthful did not significantly differ for rice and spaghetti (29.9 and 33, respectively), although masticated particle size distribution did (P < .001). Significant correlations between the degree of breakdown during mastication and the GR were observed for rice, but none for spaghetti. Individuals' peak GR (at 45 minutes) correlated significantly with the particles size distribution of their masticated rice (P = .002), and also with the total incremental area under the curve for the GR (r = -0.72; P = .012) and the incremental area under the curve for the first 45 (r = -0.74; P = .010) and 60 minutes (r = 0.73; P = .010) postconsumption. The results suggest that individual differences in mastication may be one of the causes for interindividual differences in the GR to rice but not spaghetti.

Degree of particle size breakdown during mastication may be a possible cause of interindividual glycemic variability.

The degree of mastication varies significantly between individuals and may be a cause for the considerable interindividual variation observed in the glycemic response (GR) to a single food. Using rice as the model, the aim of this study was to determine if interindividual differences in mastication and resulting degree of particle breakdown affected in vitro and in vivo glycemic potency. In a randomized crossover design, using 15 subjects, the particle size distribution and in vitro digestibility of individuals' chewed rice were determined along with their in vivo blood GR. The rapidly digested starch (RDS) content in the masticated boluses, moreover, was measured during in vitro digestion. The particle size distribution of masticated rice differed significantly interindividually. In vitro digestion of rice decreased as particle size increased. The degree of particle size breakdown as a result of mastication correlated with the RDS content in the chewed food bolus and initial digestion rate in vitro. The quantity of undigested material remaining at the end of 120-minute in vitro digestion correlated significantly with the percentage of particles greater than 2000 microm in masticated rice. The percentage of particles smaller than 500 microm correlated significantly with in vivo GR at 30 minutes postingestion but not with the total incremental area under the blood glucose curve. The degree of habitual mastication may therefore potentially influence both the magnitude and pattern of the GR and may partly explain interindividual differences in it. Although the study sets the base for future research, firm conclusions can be reached only upon the completion of additional work.

Role of body composition in the glycaemic response to foods fed to three different ethnic groups: a pilot study.

AIM: To examine the role of overweight and obesity on the glycaemic response to foods across the whole population. DESIGN: Randomised, repeated measures design. SETTING: Oxford, UK. SUBJECTS AND METHODS: Twenty-seven healthy volunteers, 9 Caucasian, 9 Asian, and 9 African, voluntarily participated in the study. The glycaemic response to two breakfast cereals and two bread types was determined in obese and overweight subjects. RESULTS: The current study shows that a very strong correlation exists between fasting blood glucose, peak change in glucose and the IAUC for glucose with each of BMI and WC (r = 0.88, 0.92; 0.82, 0.82; 0.91, 0.81; p = 0.01, respectively) for the Caucasian group. In addition, there was a strong significant negative association between the mean GI values of the four foods and the BMI for the Caucasian subjects (r = 0.61, p < 0.05). Furthermore, there was a strong positive significant association between the mean GI values of the four foods and the percentage body fat mass for the Asian subjects (r = 0.67, p < 0.05). CONCLUSIONS: This study has shown that the GI values of foods are affected by body composition in Asian and Caucasian subjects.

Glycaemic index and glycaemic load values of a selection of popular foods consumed in Hong Kong.

The objective of the present paper is to provide glycaemic index (GI) and glycaemic load (GL) values for a variety of foods that are commonly consumed in Hong Kong and expand on the international GI table of Chinese foods. Fasted healthy subjects were given 50 g of available carbohydrate servings of a glucose reference, which was tested twice, and test foods of various brands of noodles (n 5), instant cereals (n 3) and breads (n 2), which were tested once, on separate occasions. For each test food, tests were repeated in ten healthy subjects. Capillary blood glucose was measured via finger-prick samples in fasting subjects ( - 5, 0 min) and at 15, 30, 45, 60, 90 and 120 min after the consumption of each test food. The GI of each test food was calculated geometrically by expressing the incremental area under the blood glucose response curve (IAUC) of each test food as a percentage of each subject's average IAUC for the reference food. GL was calculated as the product of the test food's GI and the amount of available carbohydrate in a reference serving size. The majority of GI values of foods tested were medium (a GI value of 56-69) to high (a GI value of 70 or more) and compared well with previously published values. More importantly, our dataset provides GI values of ten foods previously untested and presents values for foods commonly consumed in Hong Kong.

Glycemic response of mashed potato containing high-viscocity hydroxypropylmethylcellulose.

Potatoes generally have one of the highest glycemic index values of any food. Relatively small differences in the glycemic response (GR) of regularly consumed starch foods have shown beneficial effects on health. Lowering the GR of a potato-based meal has potentially wide-reaching health benefits. High-viscosity hydroxypropylmethylcellulose (HV-HPMC) is a modified cellulose dietary fiber extensively used in the food industry. We hypothesized that the GR of a high-glycemic index product such as mashed potato would be lower with the addition of HV-HPMC. In a nonblind, randomized, repeat-measure, crossover controlled trial, 15 healthy adults consumed portions of mashed potato with different doses (0%, 1%, 2%, and 4%) of a specially selected and optimized HV-HPMC and a reference food (glucose) on separate occasions. Five subjects were excluded from the final analysis due to noncompliance with study procedures. Capillary blood glucose was measured in fasted subjects and at 15, 30, 45, 60, 90, and 120 minutes after starting to eat. For each sample, the incremental area under the blood glucose response curve was calculated and the GR determined. There was a significant lowering effect of HV-HPMC on GR (P < .001) of mashed potato. Glycemic responses for all mashed potato samples with the HV-HPMC were significantly lower than the standard mashed potato: 1% level (P < .05), 2% level (P < .05), and 4% level (P < .05). However, there was no significant effect of the HV-HPMC dose on GR. We conclude that addition of select HV-HPMC to mashed potato blunts GR.

High-molecular-weight barley beta-glucan in chapatis (unleavened Indian flatbread) lowers glycemic index.

Food products incorporated with soluble dietary fiber beta-glucan have shown varying effects on postprandial glycemia. The objective of the present study was to test the hypothesis that a food product fortified with barley beta-glucan and subjected to minimum processing and mild cooking might be effective in lowering glycemic response. In a randomized, single-blind, controlled crossover trial, 8 healthy human subjects (3 men, 5 women; aged 26-50 years; body mass index, <30 kg/m(2)) consumed unleavened Indian flatbreads called chapatis containing high-molecular-weight barley beta-glucan at doses of 0, 2, 4, 6, and 8 g on different occasions. Capillary blood samples were collected at 0, 15, 30, 45, 60, 90, and 120 minutes after consuming the chapatis. The incremental area under the glucose curve values for all the 5 different types of chapatis were significantly low (P < .001) compared with reference food glucose. The incremental area under the glucose curve of chapatis containing 4 and 8 g beta-glucan were significantly lower than control chapatis (P < .05). Postprandial blood glucose was significantly reduced at 45 minutes by chapatis containing 4 g (P < .05) and 8 g beta-glucan (P < .01) and at 60 minutes by chapatis with 8 g beta-glucan (P < .01). The glycemic index (GI) values of chapatis with 4 and 8 g beta-glucan were 43% to 47% lower (GI, 30 and 29, respectively) compared with chapatis without beta-glucan (GI, 54). We conclude that barley beta-glucan significantly reduces GI of chapatis, particularly at doses of 4 and 8 g per serving.

Oxidative stability and shelf-life evaluation of selected culinary oils.

Four out of eight 'healthier' oils-namely, almond oil, avocado oil, hazelnut oil and macadamia nut oil-studied were rich sources of monounsaturated fatty acids like olive oil. Grape seed oil, rice barn oil (marketed recently), toasted sesame oil and walnut oil contained high levels of essential fatty acids. The order of oxidative stability determined by Rancimat measuring of the induction period at four temperatures (90 degrees C, 100 degrees C, 110 degrees C, and 120 degrees C) was found to be macadamia oil > rice bran oil approximately toasted sesame oil > avocado oil > almond oil > hazelnut oil > grape seed oil > walnut oil. High-level monounsaturated fatty acid oils gave a linear relationship between 100 times the reciprocal of the induction period against the total unsaturated fatty acid content obtained as %C18:2 + 0.08 x C18:1 + 2.08 x %C18:3, while the polyunsaturated fatty acid oils gave an exponential relationship. In the case of rice bran and hazelnut oils, shelf-life prediction from the extrapolation of the Arrhenius plots and the Q(10) factors was compared well with that of storage time given by the oil producers. In the cases of the other oils (with an exception of macadamia nut oil), the predicted shelf-lives were significantly lower than that of the storage times; especially, walnut oil (very prone to oxidation) gave 15-20 times lower shelf-life than the best-before storage life.

Energy and nutrient intakes during different phases of the menstrual cycle in females in the United Arab Emirates.

BACKGROUND/AIMS: Evidence related to the influence of the menstrual cycle on energy and nutrient intakes is inconclusive. The purpose of the present study was to investigate energy and nutrient intakes during different phases of the menstrual cycle in adult females in the United Arab Emirates. METHODS: Forty-three females, aged between 18 and 30 years, were recruited to the study. Subjects were not using oral contraceptive pills and experienced regular menstrual cycles. Food and beverage intake was recorded, using the estimated daily record method, for 2 days of each menstrual cycle phase (pre-menstrual, menstrual and post-menstrual). Energy and nutrient intakes were analysed using Diet5 for Windows. RESULTS: Mean energy intake was significantly lower in the menstrual phase compared to the pre-menstrual phase (p = 0.002), but not the post-menstrual phase. Intakes of macronutrients and micronutrients were higher in the pre-menstrual phase compared to the menstrual and post-menstrual phases. Intakes of carbohydrates, protein and fat were significantly higher in the pre-menstrual phase than in the menstrual phase (p = 0.008, p = 0.001, p = 0.013, respectively). Similarly, intakes of vitamin C and B vitamins were significantly higher in the pre-menstrual phase than in the menstrual phase (p = 0.019, p = 0.05, respectively). CONCLUSION: Energy and nutrient intakes varied during the different phases of the menstrual cycle. These results confirm the hypothesis that food intake differs between different phases of the menstrual cycle.

Prevalence of overweight and obesity among adult females in the United Arab Emirates.

The purpose of this present study was to investigate the prevalence of overweight and obesity in adult females in the United Arab Emirates. A total number of 724 females, age 20-90 years, were recruited from the seven Emirates. The sample was divided into three age groups, 20 to <30 years, 30 to <60 years and >60 years. Height, weight and mid-upper-arm circumference were measured in each subject. Overweight and obesity were defined as a body mass index of 25.0-29.9 kg/m2 and >30 kg/m2, respectively. The prevalence of overweight and obesity were 27% and 16%, respectively. The age group between 30 and <60 years had the highest prevalence of overweight (33%) and obesity (24%). In conclusion, the findings from our study suggest that a high proportion of adult females in the United Arab Emirates are overweight and obese. The consequences of this are a serious concern for public health and need to be addressed.

The influence of adding fats of varying saturation on the glycaemic response of white bread.

The aim of this study was to examine the effect of three different fats of varying degrees of saturation on the glycaemic response of white bread. Standard white bread was served alone or with 30 g butter, 24.8 g olive oil or 24.8 g grape-seed oil. On separate occasions, 15 subjects consumed the four test foods and reference food (glucose) in 50 g available carbohydrate amounts. Capillary blood glucose was measured from finger-prick samples in fasted subjects (-5 and 0 min) and at 15, 30, 45, 60, 90 and 120 min after starting to eat. All fats lowered the glycaemic response of bread; however, no significant differences in glycaemic index were recorded between the types of fat used when ingested with bread. The results of the present study suggest that the glycaemic response of bread can be lowered using any type of fat; therefore, the use of unsaturated fat is recommended for its potential lipidaemic advantage.