Glycaemic index and glycaemic load of selected popular foods consumed in Southeast Asia

Acute Effect of Riceberry Waffle Intake on Postprandial Glycemic Response in Healthy Subjects

Gluten-free products have been developed due to increasing consumer demand. The improvement of the sensory quality and nutritional value of these products may support functional food development and provide health benefits. The purpose of this study was to develop a gluten-free waffle formulation with Riceberry rice flour by replacing the sucrose with maltitol and palm sugar powder. Evaluations of the sensory acceptability of these products and the blood glucose levels of healthy volunteers after consuming Riceberry and wheat flour waffles were carried out. The glycemic responses of the volunteers to the Riceberry and wheat flour waffles at 0, 15, 30, 45, 60, 90, 120, 150, and 180 min were monitored. In addition, the glycemic index of the products was calculated. The finding revealed that replacing sugar with 50% (w/w of total sugar) palm sugar powder and 50% maltitol was the most acceptable formulation that received the highest acceptability scores in terms of overall acceptability and texture. The blood glucose levels of both Riceberry waffle and wheat flour were not significantly different. The glycemic index of Riceberry waffle and wheat flour waffle were 94.73 ± 7.60 and 91.96 ± 6.93, respectively. Therefore, Riceberry waffle could be used as an alternative gluten-free product for celiac patients, but not for diabetic patients.

The Effect of Vacuum Deep Frying Technology and Raphanus sativus on the Quality of Surimi Cubes

This study uses a response surface methodology to optimize the vacuum deep frying process of surimi cubes. The effects of vacuum deep frying temperature, frying time, and thickness on the hardness and color difference of surimi cubes with Raphanus sativus were studied. Further, the manuscript explored the quality changes of surimi cubes under different frying processes (vacuum deep frying, atmospheric deep frying, and shallow frying). Moreover, the Chinese Min-Cantonese cuisine-Raphanus sativus was utilized as auxiliary raw material to change the hardness and reduce the oil content. The optimal parameters of response surface methodology determined were: vacuum deep frying temperature 130 °C, frying time 900 s, and thickness 0.75 cm. Additionally, under this process condition, the hardness of the surimi chunks was 2015 ± 48.17 g, and the color difference was 23.27 ± 1.86. Surimi cubes without Raphanus sativus have superior elasticity and low hardness, and surimi cubes with Raphanus sativus have little color difference and high chewability. After the vacuum deep frying process, there was a high protein content and superior crispness. Shallow frying and adding Raphanus sativus effectively reduced the product's oil content. Therefore, Raphanus sativus is suitable as a potential nutritional supplement to broaden its application in fried surimi foods.

Microbial Communities and Physicochemical Characteristics of Traditional Dajiang and Sufu in North China Revealed by High-Throughput Sequencing of 16S rRNA

The process of soybean fermentation has been practiced for more than 3,000 years. Although Dajiang and Sufu are two popular fermented soybean products consumed in North China, limited information is available regarding their microbial composition. Hence, the current study sought to investigate, and compare, the physicochemical indicators and microbial communities of traditional Dajiang and Sufu. Results showed that the titratable acidity (TA), and salinity, as well as the lactic acid, and malic acid contents were significantly higher in Sufu samples compared to Dajiang. Furthermore, Sufu samples contain abundant sucrose and fructose, while the acetic acid content was lower in Sufu compared to Dajiang samples. Moreover, the predominant bacterial phyla in Dajiang and Sufu samples were Firmicutes and Proteobacteria, while the major genera comprise Bacillus, Lactobacillus, Tetragenococcus, and Weissella. Moreover, Dajiang samples also contained abundant Pseudomonas, and Brevundimonas spp., while Halomonas, Staphylococcus, Lysinibacillus, Enterobacter, Streptococcus, Acinetobacter, and Halanaerobium spp. were abundant in Sufu samples. At the species level, Bacillus velezensis, Tetragenococcus halophilus, Lactobacillus rennini, Weissella cibaria, Weissella viridescens, Pseudomonas brenneri, and Lactobacillus acidipiscis represented the major species in Dajiang, while Halomonas sp., Staphylococcus equorum, and Halanaerobium praevalens were the predominant species in Sufu. Acetic acid and sucrose were found to be the primary major physicochemical factor influencing the bacterial communities in Dajiang and Sufu, respectively. Furthermore, Bacillus subtilis is strongly correlated with lactic acid levels, L. acidipiscis is positively correlated with acetic acid levels, while Staphylococcus sciuri and S. equorum are strongly, and positively, correlated with malic acid. Following analysis of carbohydrate and amino acid metabolism in all samples, cysteine and methionine metabolism, as well as fatty acid biosynthesis-related genes are upregulated in Dajiang compared to Sufu samples. However, such as the Staphylococcus, W. viridescens, and P. brenneri, as potentially foodborne pathogens, existed in Dajang and Sufu samples. Cumulatively, these results suggested that Dajiang and Sufu have unique bacterial communities that influence their specific characteristics. Hence, the current study provides insights into the microbial community composition in Dajiang and Sufu samples, which may facilitate the isolation of functional bacterial species suitable for Dajiang and Sufu production, thus improving their production efficiency.

A glycaemic index compendium of non-western foods

Current international tables published on the glycaemic index (GI) of foods represent valuable resources for researchers and clinicians. However, the vast majority of published GI values are of Western origin, notably European, Australian and North American. Since these tables focus on Western foods with minimal inclusion of other foods from non-Western countries, their application is of limited global use. The objective of this review is to provide the GI values for a variety of foods that are consumed in non-Western countries. Our review extends and expands on the current GI tables in an attempt to widen its application in many other regions of the world.

Reducing the glycemic impact of carbohydrates on foods and meals: Strategies for the food industry and consumers with special focus on Asia

Type 2 diabetes is increasingly prevalent in Asia, which can be attributed to a carbohydrate-rich diet, consisting of foods in the form of grains, for example, rice, or a food product made from flours or isolated starch, for example, noodles. Carbohydrates become a health issue when they are digested and absorbed rapidly (high glycemic index), and more so when they are consumed in large quantities (high glycemic load). The principal strategies of glycemic control should thus aim to reduce the amount of carbohydrate available for digestion, reduce the rate of digestion of the food, reduce the rate of glucose absorption, and increase the rate of glucose removal from blood. From a food perspective, the composition and structure of the food can be modified to reduce the amount of carbohydrates or alter starch digestibility and glucose absorption rates via using different food ingredients and processing methods. From a human perspective, eating behavior and food choices surrounding a meal can also affect glycemic response. This review therefore identifies actionable strategies and opportunities across foods and meals that can be considered by food manufacturers or consumers. They are (a) using alternative ingredients, (b) adding functional ingredients, and (c) changing processing methods and parameters for foods, and optimizing (a) eating behavior, (b) preloading or co-ingestion of other macronutrients, and (c) meal sequence and history. The effectiveness of a strategy would depend on consumer acceptance, compatibility of the strategy with an existing food product, and whether it is economically or technologically feasible. A combination of two or more strategies is recommended for greater effectiveness and flexibility.

Characterization and comparison of metaproteomes in traditional and commercial dajiang, a fermented soybean paste in northeast China

Dajiang is a popular Chinese fermented soybean condiment. Here, a comparative metaproteomic analysis of traditional and commercial dajiang was performed during fermentation. A total of 4250 and 1421 peptide sequences were obtained from 3493 and 1987 proteins in traditional and commercial dajiang, respectively. 4299 differentially expressed microbial proteins show a high metabolic heterogeneity between the two types of dajiang. The KEGG annotation indicated that there were some pathways related to human diseases, which suggest that some microbes in traditional dajiang fermentation may have greater food safety hazards. In combination with qualitative metabolomic analysis, we further traced metabolic intermediates and key enzymes in several main fermentation pathways of dajiang to be mainly affiliated with Penicillium, Tetracoccus and Bacillus in traditional samples, as well as Aspergilus in commercial samples. These results could provide information for the selection of strains that are more suitable to produce high quality dajiang and other fermented products.

Effects of Pre-Exercise High and Low Glycaemic Meal on Intermittent Sprint and Endurance Exercise Performance

The purpose of this study is to investigate the effects of ingesting either a high glycaemic index (HGI) or low glycaemic index (LGI) carbohydrate meal (preceding a 12 h overnight fast and where the meal was ingested 45-min prior to activity) on intermittent sprint and endurance exercise performance. Ten male varsity athletes from intermittent sports (age 23.6 ± 1.7 years, VO_2max 51.9 ± 4.7 mL·kg⁻¹·min⁻¹) underwent a peak velocity (V_peak) test and familiarisation session, followed by two experimental sessions in random order. Experimental sessions involved the ingestion of either an HGI or LGI meal, followed by the completion of the modified Loughborough Intermittent Shuttle Test (mLIST). There was no significant difference between HGI or LGI meals on sprint times (p = 0.62) and distance to exhaustion (p = 0.54) in the mLIST. Exercise heart rate, blood lactate and ratings of perceived exertion were also similar between the two meal trials throughout the mLIST (all p > 0.05). Subjective ratings of hunger, fullness, satiety and satisfaction were also not significantly different between the two meals. In conclusion, consuming either an HGI or LGI meal after a prolonged 12 h fast and ingesting the meal 45 min prior to exercise did not differ in either physiological, subjective and intermittent sprint and endurance performance outcomes.

An integrated metagenomic/metaproteomic investigation of microbiota in dajiang-meju, a traditional fermented soybean product in Northeast China

Dajiang-meju have been used as major ingredients for the preparation of traditional spontaneously fermented soybean paste in Northeast China. In this work, we sequenced and analyzed the metagenome of 12 dajiang-meju samples. To complement the metagenome analysis, we analyzed the taxonomic and functional diversity of the microbiota by metaproteomics (LC-MS/MS). The analysis of metagenomic data revealed that the communities were primarily dominated by Enterobacter, Enterococcus, Leuconostoc, Lactobacillus, Citrobacter and Leclercia. Moreover, changes in the functional levels were monitored, and metaproteomic analysis revealed that most of the proteins were mainly expressed by members of Rhizopus, Penicillium and Geotrichum. The number of sequences allocated to fungi in the fermentation process decreased, whereas the number of sequences assigned to bacteria increased with time of fermentation. In addition, functional metagenomic profiling indicated that a series of sequences related to carbohydrates and amino acids metabolism were enriched. Additionally, enzymes associated with glycolysis metabolic pathways were presumed to contribute to the generation of flavor in dajiang-meju. Proteins from different dajiang-meju samples involved in global and overview maps, carbohydrate metabolism, nucleic acid metabolism and energy metabolism were differentially expressed. This information improves the understanding of microbial metabolic patterns with respect to the metaproteomes of dajiang-meju and provides a powerful tool for studying the fermentation process of soybean products.

Glycaemic indices and glycaemic loads of common Korean carbohydrate-rich foods

Glycaemic index (GI) and glycaemic load (GL) values of foods consumed in Asia remain poorly characterised despite the fact that Asian diets are high in carbohydrates. We evaluated the GI and GL of the most commonly consumed carbohydrate-rich foods, according to food type and cooking methods. GI and GL values were determined using protocols from the FAO/WHO and International Standards Organization recommendations. A total of 152 healthy subjects were enrolled in the study. In all, forty-nine carbohydrate-rich foods were categorised as cereal grains, noodles and pasta, breads and other processed grains and starchy vegetables, prepared using standard cooking methods and evaluated. Cereal grains had the widest range of GI values that the food made with white rice and barley had GI values of 51–93 and 35–70, respectively, according to cooking methods, and most cereal grains had high GL values. Noodles and pasta had low to medium GI values, but most foods had high GL values. Breads had medium to high GI and GL values, while other processed grains had low to medium GI and GL values. The GI values for food made with starchy vegetables (e.g. potatoes and sweet potatoes) varied widely for different cooking methods but tended to have low GL values. In conclusion, GI values for a single food type varied widely with the cooking method used. This study of GI and GL values for common carbohydrate-rich foods provides a valuable reference for consumers and health professionals to make informed food choices for glycaemic control.

Effects of green tea extract on overweight and obese women with high levels of low density-lipoprotein-cholesterol (LDL-C): a randomised, double-blind, and cross-over placebo-controlled clinical trial

Background

This study aims to examine the effects of green tea extract (GTE) supplement on overweight and obese women with high levels of low density lipoprotein-cholesterol (LDL-C).

Methods

The randomized, double-blind, crossover and placebo-controlled clinical trial was conducted from August 2012 to December 2013. Seventy-three out of 90 subjects aged between 18 and 65 years, with body mass index (BMI) ≥ 27 kg/m² and LDL-C ≥ 130 mg/dl were included in the analysis. The subjects were randomly divided into Groups A and B. Group A received GTE supplement treatment for the first 6 weeks, while Group B received placebo daily. After 6 weeks of treatment and 14 days of washout period, Group A switched to placebo and Group B switched to GTE treatment for 6 weeks. The reduction of LDL-C level between treatments was assessed as the outcome. Additionally, anthropometric measurements, plasma lipoproteins and hormone peptides of both groups were measure at the beginning of weeks 6, 8, and 14 after treatment.

Results

Subjects treated with GTE (n = 73) for 6 weeks showed significant differences, with 4.8% (p = 0.048) reduction in LDL-C and 25.7% (p = 0.046) increase in leptin. However, there was no statistical difference in the levels of total cholesterol, triglyceride and high density lipoprotein between the GTE and placebo groups after treatments.

Conclusions

This study shows that green tea extract effectively increases leptin and reduces LDL in overweight and obese women after 6 weeks of treatment even though there were no significant changes in other biochemical markers related to overweight.

Trial registration

This clinical trial is registered with ClinicalTrials.gov: NCT02116517 on 17 April 2014. Retrospectively registered. The first patient enrolled in October 2012 and the study was completed December 2013.

Electronic supplementary material

The online version of this article (10.1186/s12906-018-2355-x) contains supplementary material, which is available to authorized users.

Does the ingestion of a 24 hour low glycaemic index Asian mixed meal diet improve glycaemic response and promote fat oxidation? A controlled, randomized cross-over study

BACKGROUND

The health benefits of consuming a low glycaemic index (GI) diet to reduce the risk of type 2 Diabetes are well recognized. In recent years the GI values of various foods have been determined. Their efficacy in constructing and consuming a low GI diet over 24 h in modulating glycaemic response has not been fully documented. The translation of using single-point GI values of foods to develop a 24 h mixed meal diet can provide valuable information to consumers, researchers and dietitians to optimize food choice for glycaemic control. By using GI values of foods to develop mixed meals, our study is the first to determine how both blood glucose and substrate oxidation may be modulated over 24 h.

METHODS

The study included 11 Asian men with a BMI between 17-24 kg/m² who followed both a 1-day low GI and 1-day high GI diet in a randomized, controlled cross-over design. Test meals included breakfast, lunch, snack and dinner. Glycaemic response was measured continuously for over 24 h and postprandial substrate oxidation for 10 h inside a whole body calorimeter.

RESULTS

The low GI diet resulted in lower 24 h glucose iAUC (860 ± 440 vs 1329 ± 614 mmol/L.min; p = 0.014) with lower postprandial glucose iAUC after breakfast (p < 0.001), lunch (p = 0.009), snack (p = 0.012) and dinner (p = 0.003). Moreover, 24 h mean amplitude of glycaemic excursion was lower during the low GI vs high GI diet (1.44 ± 0.63 vs 2.33 ± 0.82 mmol/L; p < 0.001). Simultaneously, decrease in 10 h fat oxidation was less during the low vs high GI diet (-0.033 ± 0.021 vs -0.050 ± 0.017 g/min; p < 0.001), specifically after breakfast (p < 0.001) and lunch (p < 0.001).

CONCLUSIONS

Our study corroborates that using low GI local foods to construct a 24 h low GI diet, is able to reduce glycaemic response and variability as recorded by continuous glucose monitoring. Our observations also confirm that a low GI diet promotes fat oxidation over carbohydrate oxidation when compared to a high GI diet. These observations provide public health support for the encouragement of healthier nutrition choices by consuming low GI foods.

TRIAL REGISTRATION

NCT 02631083 (Clinicaltrials.gov).