Barriers and facilitators of brown rice consumption, sensory acceptability and its effect on blood glucose level among university staff

Abstract

Background: South Africa is undergoing an epidemiologic and nutrition transition, characterized by a surge in the prevalence of overweight and obesity levels, with a noticeable increase in the consumption of high energy-dense, low nutritive foods and beverages, and a marked decrease in physical activity. Food consumption patterns in South Africa have changed dramatically over the past decades, and will most likely continue to transform over the coming decades. Diabetes is on the rise in South Africa, and a significant body of evidence suggests that targeted interventions, such as the inclusion of whole grains and a plant-based diet, are beneficial towards lowering blood glucose levels. A shift to substitute white rice with brown rice, and to increase awareness on the impact of brown rice consumption, can be a solution towards enabling behaviours aimed at subsequently maintaining and lowering blood glucose levels among adults. However, this can only happen if barriers and facilitators of brown rice consumption are identified and addressed. Additionally, pairing brown rice with meals typically enjoyed by a target population may increase acceptability of brown rice inclusion in the diet. Aim: The purpose of this research was to determine barriers and facilitators of brown rice consumption, and the sensory acceptability of brown rice when paired with typical South African dishes, lastly, to measure the effect of a brown rice meal on blood glucose level among staff members of the Durban University of Technology (DUT). Methodology: The study used a mixed methods approach; qualitative methods were used to assess the barriers and facilitators of consuming brown rice through three focus group discussions (FGDs). A quantitative method approach was applied to assess the sensory acceptability, appropriateness, and palatability of paired meals with brown rice. A selection of measuring tools and techniques were utilized, namely, FGDs, starch food frequency questionnaire (SFFO); sensory acceptability tests of brown rice cooked using various methods; sensory acceptability tests of brown rice paired dishes; anthropometrics and clinical measurements of participants, and pre-prandial and 2-hour post-prandial blood glucose measurements. Results: Three FGDs were conducted until meaningful saturation was reached; two face-toface and one in the online mode. The total number of participants in the three FGD groups consisted of 24 participants, comprising of 25% (n=6) men and 75% (n=18) women participants. Five broad themes were identified: perceptions of healthy and unhealthy foods, factors that determine food choice, factors that influence rice choice, barriers, and facilitators of including brown rice in the diet. The FGDs outlined the following barriers: brown rice is not as tasty as white rice; it requires a longer cooking time; participants had limited preparation skills; brown rice is expensive, and the designated family shopper purchases only white rice. On the other hand, facilitators of brown rice consumption included favourable sensory attributes such as crunchy mouthfeel, nuttiness, non-sticky texture and an earthy aroma. The SFFQ was administered to 94 Durban University of Technology participants who work at the institution. Significantly, the most frequently consumed starch was potatoes, where 63.8% of the study participants had eaten potatoes in the previous 7 days (p=.010). This was followed by brown bread (48.7%) and white parboiled rice (42.6%). In the total rice category, 89.4% of participants reported consuming rice, of which brown rice was the least consumed (11.7%). This alluded to a strong potential to shift from white to brown rice consumption if barriers could be overcome. For the sensory acceptability tests of brown rice paired dishes, two meals, butter chicken and lamb curry, were paired with brown rice. A strong liking was shown for both these paired meals when examining all sensory attributes (appearance, taste, smell and texture) with brown rice. The sensory evaluation (n=60) of butter chicken paired with brown rice using the 9-point hedonic scale showed that taste had the highest ranking of 7.97, followed by appearance at 7.95, texture at 7.90 and smell at 7.82. The sensory evaluation (n=60) of lamb curry paired with brown rice showed that appearance had the highest ranking at (7.87), followed by texture at (7.69), taste at (7.67) and smell at (7.52). Four different cooking methods were used to cook brown rice, namely, stove-top, gas, microwave and oven. Although brown rice prepared using microwave cooking was most preferred at (28.8%), the chi-square goodness-of-fit test showed that all four cooking methods were equally preferred (p=.834). The anthropometric results showed that the (n=51) mean waist circumference (WC) for both men and women in this study was higher than the recommended WC cut-off points. The anthropometric status in this study denotes that high WC places participants in this study at a greater risk of chronic diseases. The anthropometric measure for weight (n=58), one participant was underweight (1.15%); 28.4% (n=25) participants were normal weight; 35.22% (n=31) participants were overweight, and 35.23% (n=31) participants were obese. The anthropometric for height (n=58) in centimetres was indicated at 1.60 for women and 1.71 for men. After participants observed an overnight fast, (n=60) the mean pre-prandial blood glucose level was 5.54 mmol/L, 2 hours after consuming a healthy brown rice breakfast, the mean post-prandial blood glucose was 5.45 mmol/L. Analysis from a Wilcoxon signed ranks test showed that there was no significant difference in blood pre to post eating, (p=.771). Analysis using a paired ttest showed that there was no significant difference in blood values before and after eating, (p=.431), meaning that blood glucose levels were maintained after consuming the brown rice breakfast. The findings of this result endorse the healthful benefits of brown rice, as it is widely evidenced in existing literature that brown rice reduces insulin spikes and aids in the stabilisation of the body's blood sugar levels due to its low glycaemic index. There is potential to shift participants from white to brown rice however, this can be facilitated by deliberately pairing brown rice with dishes most preferred by the target population. Once palates become more accustomed to brown rice, it may be easier to encourage brown rice consumption with other dishes. No significant differences in post-prandial blood were found across the Body Mass Index (BMI) categories, F (3, 51) (p= .970, p=.414). However, there was a significant moderate positive correlation (r=.365) between WC and post-prandial blood scores, (p=.011) alluding to the risk factor association of increased WC and blood glucose levels. Conclusion: The health benefits associated with brown rice consumption as outlined in this research, warrants that further research be conducted on the acceptance of brown among consumers in South Africa. The favourable acceptance of brown rice when paired with butter chicken, lamb curry; egg fried rice and breakfast muesli concept as depicted in this study, indicates scope for a much larger percentage of brown rice consumption than the current 11.7%. It also alludes to the importance of contextualising meal combinations and sensory acceptability, to fit specific contexts and thus influence consumption patterns. Shifting individuals starch preference to more healthful starches, like brown rice, can contribute to health gains for a target population. Alongside this, consumer education, recipes and sensory sampling can help consumers feel part of the solution. Many studies have documented the healthful benefits of making the transitional shift from white rice to brown rice. However, this study notes despite its healthful benefits, that the acceptance of brown rice has been limited, compelling the activation of consumer education and practical preparation solutions to ease consumer acceptance of brown rice.