Microwave irradiation of guar seed flour: Effect on anti-nutritional factors, phytochemicals, in vitro protein digestibility, thermo-pasting, structural, and functional attributes.

Guar seed flour (GSF) has a high amount of carbohydrates, proteins, phytochemicals, and anti-nutritional factors (ANFs), which limits its use. To address this issue, the current study was undertaken to understand the effect of microwave (MW) irradiation on ANFs, phytochemicals, in vitro protein digestibility (IVPD), and functional attributes of GSF at varying power density (Pd: 1-3 W/g) and duration (3-9 min). The ANFs were determined using a colorimetric assay and a Fourier transform infrared spectrum. At 3 Pd-9 min, the maximum reduction in ANFs (tannin, phytic acid, saponin, and trypsin inhibitor activity) was observed. Higher Pd and treatment duration increased antioxidant activity and total phenolic content, except for total flavonoid content. Furthermore, compared to the control sample (78.38%), the IVPD of the GSF samples increased to 3.28% (3 Pd-9 min). An increase in Pd and duration of MW treatment improved the thermal and pasting properties of GSF samples up to 2 Pd-9 min. Due to inter- and intramolecular hydrogen bonding degradation, the relative crystallinity of the 3 Pd-9 min treated GSF sample was 30.58%, which was lower than that of the control (40.08%). In MW-treated samples, SEM images revealed smaller clusters with rough and porous structures. However, no noticeable color (ΔE) changes were observed in MW-treated samples. Aside from water absorption capacity and water solubility index, MW treatment reduced oil absorption capacity, foaming capacity, and emulsifying capacity. As demonstrated by principal component analysis, MW irradiation with moderate Pd (2-3) was more effective in reducing ANFs, retaining nutritional contents, and improving the digestible properties of GSF, which could be a potential ingredient for developing gluten-free products.

Effect of extraction pH on amino acids, nutritional, in-vitro protein digestibility, intermolecular interactions, and functional properties of guar germ proteins.

The chemical compositions, intermolecular interactions, and functional properties of guar germ proteins (GGP) were investigated at different extraction pH (7 to 11). The protein efficiency ratio, essential amino acid index (46.53), predicted biological value (39.02), nutritional index (42.67), and protein purity (91.69 %) were found to be highest at pH 9. The in-vitro protein digestibility of GGP sample was highest at pH 11. From SDS-PAGE, the band intensity (<10 kDa) became thinner with an increase in extraction pH from 7 to 9 and then thicker. Meanwhile, smallest particle size and weaker ionic and hydrogen bonds were found at pH 11. The ß-sheet content was more dominating in GGP samples. Moreover, higher denaturation temperatures of GGP samples indicated that protein molecules had a compact tertiary structure. Furthermore, the GGP extracted at pH 7 showed better functional properties. The principal component analysis suggested that pH 9 was more suitable for isolating GGP.

Atmospheric cold plasma induced nutritional & anti-nutritional, molecular modifications and in-vitro protein digestibility of guar seed (Cyamopsis tetragonoloba L.) flour.

The present study was carried out to investigate the effect of atmospheric cold plasma treatment on the nutritional, anti-nutritional, functional, morphological, and digestibility of guar seed (Cyamopsis tetragonoloba L.) flour. Here, guar seed flour was kept inside the plasma reactor for 5 to 20 min at different power levels (10 & 20 kV). The cold plasma treatment (CPT) significantly (p < 0.05) reduced the carbohydrate (46.87 - 36.81 %), protein (27.15 - 25.88 %), and increased the WAC (1.89 - 2.91 g/g), OAC (1.18 - 2.17 g/g), FC (113 - 186.17 %), and pasting properties of guar seed flour. High-intensity plasma-treated samples (20 kV-20 min) contained lesser tannin, phytic acid, and saponin with reduced the nutritional value. The FTIR spectrum suggested that functional group formation or destruction might have occurred in the plasma-treated samples. Additionally, the crystallinity is reduced with increasing applied voltage or duration. The SEM analysis reveals that CPT resulted in the formation of rough surfaces with highly porous structures. On the other hand, CPT significantly reduced the trypsin inhibitor activity and had a minor impact on in-vitro protein digestibility except for the 20 kV-20 min treated sample. In PCA analysis, 10 kV-15 min treated samples exhibited better nutritional value, functional, and pasting properties with maximum impact of anti-nutritional factors. From the results, it can be concluded that treatment duration rather than the applied voltage plays a significant role in preserving the nutritional content.

Advances in isolation, characterization, modification, and application of Chenopodium starch: A comprehensive review.

The Chenopodium genus includes >250 species, among which only quinoa, pigweed, djulis, and kaniwa have been explored for starches. Chenopodium is a non-conventional and rich source of starch, which has been found effective in producing different classes of food. Chenopodium starches are characterized by their smaller granule size (0.4-3.5 µm), higher swelling index, shorter/lower gelatinization regions/temperature, good emulsifying properties, and high digestibility, making them suitable for food applications. However, most of the investigations into Chenopodium starches are in the primary stages (isolation, modification, and characterization), except for quinoa. This review comprehensively explores the major developments in Chenopodium starch research, emphasizing isolation, structural composition, functionality, hydrolysis, modification, and application. A critical analysis of the trends, limitations, and scope of these starches for novel food applications has also been provided to promote further scientific advancement in the field.

Cultivation of microalgae on food waste: Recent advances and way forward.

Microalgae are photosynthetic microbes that can synthesize compounds of therapeutic potential with wide applications in the food, bioprocessing and pharmaceutical sector. Recent research advances have therefore, focused on finding suitable economic substrates for the sustainable cultivation of microalgae. Among such substrates, food derived waste specifically from the starch, meat, dairy, brewery, oil and fruit and vegetable processing industries has gained popularity but poses numerous challenges. Pretreatment, dilution of waste water supernatants, mixing of different food waste streams, utilizing two-stage cultivation and other biorefinery approaches have been intensively explored for multifold improvement in microalgal biomass recovery from food waste. This review discusses the advances and challenges associated with cultivation of microalgae on food waste. The review suggests that there is a need to standardize different waste substrates in terms of general composition, genetically engineered microalgal strains, tackling process scalability issues, controlling wastewater toxicity and establishing a waste transportation chain.

Quality characteristics of sand, pan and microwave roasted pigmented wheat (Triticum aestivum).

Present study investigated the effect of sand, pan and microwave roasting on physico-chemical, functional and rheological properties of yellow (YW), purple (PW), and black wheat (BW). All roasting methods enhanced the browning index (BI), water absorption capacity (WAC) and oil absorption capacity (OAC) roasted wheat flour. Microwave roasting showed significantly higher impact on BI (58.61% for YW, 131% for BW and 83.85% for PW) and WAC (47.93% for YW, 44.63% for BW and 32.09% for PW). However, the decrease in density, emulsifying capacity (EC), foaming capacity (FC), total phenolic content (TPC), total flavonoid content (TFC), and total anthocyanin content (TAC), and antioxidant activity was observed on roasted wheat flour. Roasting also affected the pasting properties of wheat flours and peak, trough, breakdown and final viscosity decreased.