The effect of the lupine flour and corn starch on the rheological properties of dough, texture and organoleptical properties of gluten-free cake

Celiac disease is one of the food intolerance disorders in the world. This disease is provoked in genetically susceptible individuals by dietary exposure to wheat gluten and similar proteins in other closely related cereals. The only effective treatment is strict adherence to a 100% gluten free diet for life (Malekzadeh and Shakeri 1386). Patients with Celiac disease should avoid taking gluten-based products (Rampertab and Mullin 2014). Therefore, planning for the production of gluten-free products and their improvement is of particular importance. Lupine or lupines (North America), is a genus of flowering plants in the legume family. Lupine is a leguminous plant that has been studied in this study as a rich source of protein and dietary fiber on the characteristics of gluten-free cake (Kohajdova et al., 2011). The objective of this study was to evaluate the effects of lupine flour (5, 10 and 15%) as a rich source of protein (about 42%) and dietary fiber (about 40%), corn starch (85, 90 and 95%), guar and carrageenan gums (1, 1.5 and 2%) on cake tissue (first and fifteenth days) and organoleptic properties of cake (odour, taste, texture, color and overall acceptance). By adding lupine flour to corn starch and guar and carrageenan gums, gluten-free cake was produced and the optimum formula was obtained with 15% lupine, 85% corn starch, 1% guar gum and 1% carrageenan gum.

In this study, the effects of lupine flour, corn starch, guar and carrageenan gums on cake tissue and organoleptic properties were investigated. Lupine flour was purchased from Markal LTD, France. Guar gum from Gum Chemicals LTD, India and carrageenan gum from MSC, Korea. Mono- Diglyceride, gluten-free baking powder, corn starch, oil, salt, sugar and vanilla were prepared by the Nan Sahar group. Cake production was also produced at the Nan Sahar Institute. The cooking temperature was 180°C and the cooking time was 25 minutes. After cooking, they were cooled for 40 minutes at ambient temperature and packed in polyethylene bags.
In the present study, 20 formulations produced according the mixture design (D- optimal) approach and the effect of Lupine flour (5, 10 and 15%), corn starch (85, 90 and 95%), guar and carrageenan gums (1, 1.5 and 2%), on the viscosity of dough, tissue and sensory evaluation of cake were investigated. Tests were performed in three replications. Analysis of variance (ANOVA) and comparisons of treatments were done using Combined Design, by Design Expert 7.1.5 software.

This research was designed, analyzed and optimized by using the Design-Expert software, Combined D-Optimal Design. ANOVA results showed that fitted models for responses were meaningful (p <0.05). Therefore, the accuracy of the model was confirmed for fitting the information. High content of dietary fiber in lupine flour, by absorbing more water, prevents hardness of the cake tissue and reducing the staling process. Dietary fibre is one of the most important food ingredients used in nutritional and functional foods as it is one of the first ingredients to be associated with the health trend in the 1980s, particularly in bakery and cereal products. Guar and carrageenan gums increase tissue hardness because the gums strengthened the walls of cells forming cavities inside the cake structure. After 15 days, tissue hardness was lower in samples with high lupine. The results of viscosity measurements showed that Lupine flour due to its lack of gluten, reduced viscosity and guar and carrageenan gums, with more water absorption increased viscosity. The results of texture measurement showed that Lupine flour, guar and carrageenan gums reduces the hardness of the tissue. The results of sensory evaluations showed that lupine flour and guar gum improves these properties, but carrageenan gum did not affect the improvement of these. Investigating the effects of Lupine flour on the taste, odour, color, tissue and overall acceptance of gluten-free cakes showed that the increase in Lupine flour had a signtificant effect on them. The protein contained in the lupine flour and glucose in the formulation of gluten-free cake as Millard's precursor compounds, and with the help of the Millard reaction, improves taste and aroma in the gluten-free product. High content of carotenoids in Lupine flour, improved the appearance of the color. Soluble fiber in lupine flour improves the texture and creates a more acceptable tissue for the product. The overall acceptance of samples increased with increasing level of lupine flour.

The results of this study showed that the addition of lupine flour to corn starch and guar and carrageenan gums have positive effects on the texture and sensory properties of gluten-free cake. Lupin flour is not only high in dietary fibre but it is also high in protein contents (41–44%) which make it a unique ingredient of high nutritional and commercial value. According to the results, formulation with 15% Lupine flour, 85% corn starch, 1% Guar and 1% carrageenan gums, had a good viscosity, and the tissue was softer and more acceptable and received the highest overall acceptance rating and was selected as the optimal formulation. Lupin flour has shown potential for the manufacture of a range of fibre-enriched products with high consumer acceptability. Consumption of lupin flour-enriched foods has been proven to have many health benefits. Bread prepared by adding lupin flour helped in reducing blood pressure and cardiovascular risk. Addition of lupin fibre to the diet provided favourable changes to some serum lipid measures in men which suggested this novel ingredient may be useful in the dietary reduction of coronary heart disease risk. Breakfasts with lupin flour-enriched bread resulted in significantly higher self-reported satiety and lower energy intake at lunch than normal breakfast. Increasing both protein and fibre intakes, at the expense of refined carbohydrate, may benefit blood pressure. Lupin flour, which is high in both protein and dietary fibre contents, could be an ideal food ingredient that can be used to get the combined effect of protein and fibre in lowering the blood pressure. As compared with other natural protein and dietary fibre sources, lupin flour is lower in
cost. Therefore, substitution of sweet lupin flour would improve the nutritional value and quality of muffins at economically affordable price.