Production of innovative gluten-free breakfast cereals based on red and black rice by extrusion processing technology

Functional Foods from Black Rice (Oryza sativa L.): An Overview of the Influence of Drying, Storage, and Processing on Bioactive Molecules and Health-Promoting Effects

Black rice (Oryza sativa) stands out for its high content of bioactive compounds with functional properties that play an important role in health benefits. The phytochemical level is affected by industrial processing due to its instability to the hydrothermal process. Studies about the influence of industrial processing on the phytochemical profile of black-rice-based foods are still scarce. This study carried out a comprehensive review of the influence of industrial applications on the bioactive compounds in food products based on black rice and their health-promoting effects. Most industrial processes such as drying, storage, cooking, and extrusion affect phytochemical content and antioxidant capacity. Alternatively, technologies such as fermentation, UV-C irradiation, and sprouting can maintain or improve the phytochemical content in black rice products.

Rice-Based Gluten-Free Foods and Technologies: A Review

Rice, one of the most widely consumed staples worldwide, serves as a versatile gluten-free substitute. However, review articles on technological developments in grain-free production focusing on rice are scarce. This review assesses various research results concerning the quality attributes of rice-based gluten-free foods, including bread, pasta, and beer. To optimize the key attributes in processed products, such as dough leavening in bread and the physical and cooking properties of noodles and pasta, research has focused on blending different gluten-free grains and incorporating additives that mimic the gluten function. Additionally, various processing technologies, such as starch preprocessing and extrusion puffing processes, have been employed to boost the quality of rice-based gluten-free products. Today, a variety of products, including bread, noodles, and beer, use rice as a partial replacement for barley or wheat. With rapid advancements in technology, a noticeable portion of consumers now shows a preference for products containing rice as a substitute. This trend indicates that rice-based gluten-free foods can be enhanced by leveraging the latest developments in gluten-free product technologies, particularly in countries where rice is a staple or is predominantly cultivated.

New Breakfast Cereal Developed with Sprouted Whole Ryegrass Flour: Evaluation of Technological and Nutritional Parameters

Ryegrass is one such cereal that has been underutilized in human nutrition despite its high nutritional and functional value due to the presence of phytochemicals and dietary fibers. Exploiting ryegrass for human consumption is an exciting option, especially for countries that do not produce wheat, as it is easily adaptable and overgrows, making it economically viable. This study evaluated the nutritional content of γ-aminobutyric acid and bioactive compounds (total soluble phenolic compounds) and the physicochemical and technological properties of partially substituting maize flour (MF) with sprouted whole ryegrass flour (SR) in developing extrusion-cooked breakfast cereals. A completely randomized design with substitutions ranging from 0 to 20% of MF with SR was employed as the experimental strategy (p < 0.05). Partial incorporation of SR increased the content of γ-aminobutyric acid and total soluble phenolic compounds. Using sprouted grains can adversely affect the technological quality of extruded foods, mainly due to the activation of the amylolytic enzymes. Still, ryegrass, with its high dietary fiber and low lipid content, mitigates these negative effects. Consequently, breakfast cereals containing 4 and 8% SR exhibited better physicochemical properties when compared to SR12, SR16, SR20, and USR10, presenting reduced hardness and increased crispness, and were similar to SR0. These results are promising for ryegrass and suggest that combining the age-old sprouting process with extrusion can enhance the nutritional quality and bioactive compound content of cereal-based breakfast products while maintaining some technological parameters, especially crispiness, expansion index, water solubility index, and firmness, which are considered satisfactory.

Technological and prebiotic aspects of young bamboo culm flour (Dendrocalamus latiflorus) combined with rice flour to produce healthy extruded products

Young bamboo culm flour (YBCF) has proved to be a healthy and sustainable ingredient, due to its high fiber content and high yield of bamboo crops. The present study evaluated the effects of YBCF from Dendrocalamus latiflorus on the physicochemical, technological properties and prebiotic activity of rice-based extrudates aiming to expand its application. The extrudates were produced in a twin-screw extruder with different RF:YBCF concentrations (100:0; 95:5, 90:10, and 85:15 %). During the process, the specific mechanical energy increased as YBCF content increased because of the high shear favored by YBCF particles. With increasing RF replacement by YBCF, the extruded products presented a significant (p < 0.05, by the Scott-Knott test) increase in hardness (57.37 to 82.01 N) and water solubility index (12.80 to 34.10 %), as well as a decrease in color luminosity (L*=85.49 to 82.83), expansion index (2.68 to 1.99), and pasting properties. In addition, all extrudate samples presented bifidogenic activity. Therefore, YBCF exhibited attractive technological properties and can be used as an ingredient in the production of healthy and sustainable extruded products.

Optimization of process parameters for the development of gluten free extruded breakfast cereal based on Quinoa, finger millet and red rice using RSM

Current research aims to evaluate the effect of high shear extrusion on quinoa, finger millet, and red rice composite flour-based breakfast cereal using response surface methodology with extruder barrel temperature (120-130 °C), screw speed (320-350 rpm) and feed moisture content (10-20 g/100 g) as independent variables. Product responses were fitted on to mathematical model using second-order polynomial equations. Multiple regression analysis of data revealed the high statistical significance of respective mathematical models. Numeric optimization based on acceptable product characteristics revealed optimized processing conditions (barrel temperature 130 °C, screw speed 350 RPM, and feed moisture content 20 g/100 g) with a desirability of 0.9373. Extrudates developed using selected processing conditions along with optimized ones and control were characterized for their nutrient profile and crystallinity. Breakfast cereal developed using optimized processing conditions showed a better nutritional profile and reduction in crystallinity of product after high shear extrusion processing represented starch gelatinization.

Andean Sprouted Pseudocereals to Produce Healthier Extrudates: Impact in Nutritional and Physicochemical Properties

The tailored formulation of raw materials and the combination of grain germination and extrusion processes could be a promising strategy to achieve the desired goal of developing healthier expanded extrudates without compromising sensory properties. In this study, modifications in the nutritional, bioactive profile and physicochemical properties of corn extrudates as influenced by the complete or partial replacement by sprouted quinoa (Chenopodium quinoa Willd) and cañihua (Chenopodium pallidicaule Aellen) were investigated. A simplex centroid mixture design was used to study the effects of formulation on nutritional and physicochemical properties of extrudates, and a desirability function was applied to identify the optimal ingredient ratio in flour blends to achieve desired nutritional, texture and color goals. Partial incorporation of sprouted quinoa flour (SQF) and cañihua flour (SCF) in corn grits (CG)-based extrudates increased phytic acid (PA), total soluble phenolic compounds (TSPC), γ-aminobutyric acid (GABA) and oxygen radical antioxidant activity (ORAC) of the extrudates. Sprouted grain flour usually results in an deleterious effect physicochemical properties of extrudates, but the partial mixture of CG with SQF and SCF circumvented the negative effect of germinated flours, improving technological properties, favoring the expansion index and bulk density and increasing water solubility. Two optimal formulations were identified: 0% CG, 14% SQF and 86% SCF (OPM1) and 24% CG, 17% SQF and 59% SCF (OPM2). The optimized extrudates showed a reduced amount of starch and remarkably higher content of total dietary fiber, protein, lipids, ash, PA, TSPC, GABA and ORAC as compared to those in 100% CG extrudates. During digestion, PA, TSPC, GABA and ORAC showed good stability in physiological conditions. Higher antioxidant activity and amounts of bioaccessible TSPC and GABA were found in OPM1 and OPM2 digestates as compared to those in 100% CG extrudates.

Some physical, functional and antinutrients of breakfast cereals from blends of guinea corn, pigeon pea and mango flour using mixture-process design

Some functional, physical and anti-nutritional factors of breakfast cereals from blends of sorghum (X₁), pigeon pea (X₂) and mango (X₃) flours were evaluated using mixture-process design. The flours were blended in ratios of 1:0:0, 0:1:0, 0:0:1, 05:0.5:0, 0.5:0:0.5, 0:0.5:0.5, and 1/3:1/3:1/3, for sorghum, pigeon pea, and mango flour, respectively. Twenty-eight samples were generated from a multiplicative (2³-1) simplex centroid mixture design and a (2, 2) full factorial design. The samples were roasted at varying temperatures (Z₁) (250 and 270 °C) and times (Z₂) (4 and 7 min). The water absorption capacity (WAC), pH, bulk density (BD), foam capacity (FC), haemagglutinin, phytates, and tannins were evaluated. Significant (p < 0.05) regression models were generated to explain these responses. The temperature time-combination did not significantly (p > 0.05) affect pH changes. For WAC, BD, FC, and the antinutrients, there was no clear trend to describe the effect of mixture components and process variables. Experimental runs with the same mixture formulation, processed at different temperature-time combinations had different values for these attributes with the degree of reduction of antinutrients being a simultaneous effect of these variables. Cross interactions between the mixture and process variables showed that the selected properties were dependent both on the mixture and processing conditions.

Performance of Thermoplastic Extrusion, Germination, Fermentation, and Hydrolysis Techniques on Phenolic Compounds in Cereals and Pseudocereals

Bioactive compounds, such as phenolic compounds, are phytochemicals found in significant amounts in cereals and pseudocereals and are usually evaluated by spectrophotometric (UV-VIS), HPLC, and LC-MS techniques. However, their bioavailability in grains is quite limited. This restriction on bioavailability and bioaccessibility occurs because they are in conjugated polymeric forms. Additionally, they can be linked through chemical esterification and etherification to macro components. Techniques such as thermoplastic extrusion, germination, fermentation, and hydrolysis have been widely studied to release phenolic compounds in favor of their bioavailability and bioaccessibility, minimizing the loss of these thermosensitive components during processing. The increased availability of phenolic compounds increases the antioxidant capacity and favor their documented health promoting.

Effect of Processing on Bioactive Compounds, Antioxidant Activity, Physicochemical, and Sensory Properties of Orange Sweet Potato, Red Rice, and Their Application for Flake Products

Orange sweet potato (OSP) and red rice (RR) are rich sources of health benefit-associated substances and can be conventionally cooked or developed into food products. This research approach was to closely monitor the changes of bioactive compounds and their ability as antioxidants from the native form to the food products which are ready to be consumed. Moreover, this research explored the individual carotenoids and tocopherols of raw and cooked OSP and RR and their developed flake products, and also investigated their antioxidant activity, physicochemical properties, and sensory properties. Simultaneous identification using the liquid chromatographic method showed that OSP, RR, and their flake products have significant amounts (µg/g) of β-carotene (278.58–48.83), α-carotene (19.57–15.66), β-cryptoxanthin (4.83–2.97), α-tocopherol (57.65–18.31), and also γ-tocopherol (40.11–12.15). Different responses were observed on the bioactive compound and antioxidant activity affected by heating process. Meanwhile, OSP and RR can be combined to form promising flake products, as shown from the physicochemical analysis such as moisture (5.71–4.25%) and dietary fiber (13.86–9.47%) contents, water absorption index (1.69–1.06), fracturability (8.48–2.27), crispness (3.9–1.5), and color. Those quality parameters were affected by the proportions of OSP and RR in the flake products. Moreover, the preference scores (n = 120 panelists) for the flakes ranged from slightly liked to indifferent. It can be concluded that OSP and RR are potential sources of bioactive compounds which could act as antioxidants and could be developed into flake products that meet the dietary and sensory needs of consumers.