Development of instant low glycemic rice using extrusion technology and its characterization

Proximate, structural, textural, sensory and microbiological properties of non-gluten extrudate using Sorghum (Sorghum bicolor L. Moench) and a sprouted legume (Phaseolus lunatus L.)

The inclusion of legumes as functional ingredients in a gluten-free extrusion process has been gaining attention in recent times. In this study, sorghum and germinated lima bean flour (100, 90:10, 80:20, 70:30, 60:40 and 50:50) was extruded (feed moisture - 18%, screw speed - 250 rpm, barrel temperatures 50 °C-120 °C-120 °C, die hole diameter - 3 mm) and analysed for functional, proximate, textural, structural, pasting, microbiological and sensory properties. With 100% sorghum used as control, lima beans addition significantly (p < 0.05) improved the loose (0.37-0.44 g/ml) and packed (0.63-0.72 g/ml) bulk density, while water (5.00-3.15 g/g) and oil (2.45-1.60 g/g) absorption capacity and expansion ratio (3.11-2.30) decreased, respectively. An increase in protein (12.77-18.00%), crude fibre (2.58-5.17%) and ash content (2.11-3.12%) were observed in the extrudate, while the (L*) colour parameter (54.49-43.62), hardness (180.04-78.36 N) and pasting viscosities reduced with addition of lima beans. The structural micrograph depicted air-trapped bubbles with thick walls after adding lima beans, while a notable decline in microbial count below approved limits was observed after 8 weeks of storage. Sensory scores showed that values obtained were above average with the 90:10 sorghum-lima bean ratio having the highest score. The economic and industrial value of underutilised legumes such as lima bean can be promoted as functional ingredients via extrusion in addressing coeliac disease and alternative sources of protein, especially in developing countries.

Optimization of the extrusion parameters for the production of lentil-quinoa extrudates enriched with pumpkin

This study aimed to develop a protein-fiber-rich extruded product based on yellow lentil, quinoa, and pumpkin flours. The final product quality is affected by formulation and extrusion parameters. Therefore, the effect of the pumpkin-flour ratio (A: 25-75%) and feed moisture content (C: 14-22%) besides barrel screw speed (B: 120-180 rpm) on the physical attributes of extrudates was investigated. Box-Behnken experimental design and stepwise-response surface method were used to analyze the effects of various process variables and ingredients on extrudates. The pumpkin-flour ratio had a significant positive correlation with bulk density (BD), water solubility index (WSI), and oil absorption index. Whereas the correlation between pumpkin-flour ratio with hardness, porosity, expansion ratio (ER), and water absorption index (WAI) was negative (P < 0.05). The feed moisture content positively affected the water activity (aw) and WAI and negatively affected the harness of samples (P < 0.05). The screw speed had a positive effect on ER, porosity, and WSI, whereas it negatively influenced the hardness, BD, and aw. By increasing the pumpkin-flour ratio, air cell size and wall thickness of samples had been decreased. The results showed that 44.2% pumpkin flour, 22% feed moisture, and 172.1 rpm screw speed gave an optimized product. There was no significant difference between predicted and experimental values (except for ER). The optimized snack was a good source of fiber (around 15%), protein (17.3%), and antioxidants (TPC = 15.28 mg GAE.g-1 and antiradical scavenging activity (DPPH) = 33.66%). The caloric value of the optimized snack was 362.6 cal.100g-1. The current formulation can be considered as the base of snack food or plant-based meat alternatives.

Effect of Marjoram Leaf Powder Addition on Nutritional, Rheological, Textural, Structural, and Sensorial Properties of Extruded Rice Noodles

Food-to-food fortification is an emerging technique to enrich the micronutrients in foods. Pertaining to this technique, noodles could also be fortified with natural fortificants. In this study, marjoram leaf powder (MLP) at a level of 2-10% was used as a natural fortificant to produce fortified rice noodles (FRNs) through an extrusion process. The MLP addition caused a significant increase in the iron, calcium, protein, and fiber in the FRNs. The noodles had a lower whiteness index than unfortified noodles but had a similar water absorption index. The water solubility index increased significantly due to the higher water retention ability of MLP. A rheological study showed a minimal effect of fortification on the gelling strength of the FRNs at lower levels. The microstructural studies found incremental cracks, which facilitated a lower cooking time and hardness but had an insignificant effect on the cooked noodle texture. Fortification improved the total phenolic content, antioxidant capacity, and total flavonoid content. However, no significant changes in bonds were observed, but a reduction in the noodles' crystallinity could be seen. The sensory analysis of the noodles reflected a higher acceptability of the 2-4% MLP fortified samples compared to the others. Overall, the MLP addition improved the nutritional content, antioxidant activity, and the cooking time but slightly affected the rheological, textural, and color properties of the noodles.

Physical, Chemical and Functional Attributes of Neera Honey Infused Extrudates

Owing to the demand for the consumption of healthy extrudates, this study explored the infusion of neera (coconut inflorescence sap) honey in rice flour, corn flour and coconut milk residue blend-based extrudates. Neera honey, the concentrated coconut inflorescence sap, has numerous nutrients and a natural source of essential vitamins. Hence, the potential of neera honey as a biofortifying compound for the production of healthy extrudates was investigated. The rice and corn based extrudates supplemented with different concentration of neera honey have been prepared until the mix reaches 16 and 20% (w.b.) of feed moisture. Effect of addition of neera honey on the physical properties (expansion ratio, bulk density, specific length), functional properties (water absorption, water solubility, oil absorption), biochemical properties (total carbohydrates, total sugar, reducing sugar, phenolics, flavonoids, antioxidants), color parameters(L*, a*, b*), proximate compositions (moisture content, ash, protein, fat) and mineral profile of extrudates were recorded. Results suggest that addition of neera honey had a significant (p ˂ 0.05) impact on all the physico-chemical parameters evaluated. Incorporation of neera honey (feed moisture -20%) resulted in extrudates with less expansion, high bulk density and specific length, having high sugar, protein, phenolics, vitamin C and antioxidant activity. The combination of 60% rice flour + 25% corn flour +15% coconut milk residue samples infused with neera honey upto 16% feed moisture was found suitable for the preparation of nutritious extrudates based on functional characterization and minerals evaluation.

An overview of the nutritional profile, processing technologies, and health benefits of quinoa with an emphasis on impacts of processing

Consumers are becoming increasingly conscious of adopting a healthy lifestyle and demanding food with high nutritional values. Quinoa (Chenopodium quinoa Willd.) has attracted considerable attention and is consumed worldwide in the form of a variety of whole and processed products owing to its excellent nutritional features, including richness in micronutrients and bioactive phytochemicals, well-balanced amino acids composition, and gluten-free properties. Recent studies have indicated that the diverse utilization and final product quality of this pseudo-grain are closely related to the processing technologies used, which can result in variations in nutritional profiles and health benefits. This review comprehensively summarizes the nutritional properties, processing technologies, and potential health benefits of quinoa, suggesting that quinoa plays a promising role in enhancing the nutrition of processed food. In particular, the effects of different processing technologies on the nutritional profile and health benefits of quinoa are highlighted, which can provide a foundation for the updating and upgrading of the quinoa processing industry. It further discusses the present quinoa-based food products containing quinoa as partial or whole substitute for traditional grains.

Assessment of physicochemical, rheological, and thermal properties of Indian rice cultivars: Implications on the extrusion characteristics

The implications of physicochemical, rheological, and thermal properties of seven eminent Indian rice cultivars (PR 114, 121, 122, 123, 124, 126, and 127) on the extrusion behavior and physico-functionalities of the extrudates were investigated. The amylose and amylopectin content of the cultivars ranged between 12.72 to 28.86% and 71.14 to 87.28% in addition with protein and crude fat content that varied from 7.05 to 9.15% and 0.49 to 1.17%, respectively. The onset (r = 0.98), peak (r = 0.95), and conclusion (r = 0.98) temperatures of the cultivars were in positive correlation with amylose. Likewise, pasting temperature (r = 0.979), final viscosity (r = 0.91), set back viscosity (r = 0.89), and stability ratio (r = 0.90) of the cultivars demonstrated a significant positive correlation with the amylose content. However, peak (r = - 0.879) and hold viscosity (r = - 0.89) were negatively correlated. The cultivars were extruded at feed moisture of 15%, screw speed of 500 rpm and barrel temperature of 150°C. The extrudates characteristics viz., expansion ratio-1.82 (PR 123); bulk density-184 g/cc (PR 123); specific mechanical energy-262.35 Wh/kg; water absorption index (WAI)-6.26 (PR 122); water solubility index-48.52% (PR 123); hardness-148.63 N (PR 122); and hydration power-284% (PR 122) were viably hyphenated with the physicochemical and rheological behavior of cultivars. The physico-functional characterization of the extrudates in terms of their starch and protein structural indexes, α-amylase susceptibility; water soluble carbohydrates and proteins revealed the possibility of exploring these cultivars as a functionally viable and diverse ingredient for the production of ready-to-eat extrudates.