Highly nutritious lentil proteins (LP) have recently attracted interest in the food industry. However, due to their low solubility, extensive application of LP is severely limited. This study describes a new and successful method for overcoming this challenge by improving the nutritional–functional properties of LP, particularly their solubility and protein quality. By combining protein complexation with water kefir-assisted fermentation, the water solubility of native LP (~58%) increases to over 86% upon the formation of lentil–casein protein complexes (LCPC). Meanwhile, the surface charge increases to over −40 mV, accompanied by alterations in secondary and tertiary structures, as shown by Fourier-transform infrared and UV-vis spectra, respectively. In addition, subjecting the novel LCPC to fermentation increases the protein digestibility from 76% to over 86%, due to the reduction in micronutrients that have some degree of restriction with respect to protein digestibility. This approach could be an effective and practical way of altering plant-based proteins.

The purpose of this study was to identify novel natural bioactive phenolic compounds with anti-oxidant, anti-allergic, anti-hypertensive, and anti-diabetic properties in wheat protein fractions. Free and bound phenolic compounds were isolated from the albumin, glutelin-1, glutelin-2, prolamin, and globulin wheat protein fractions. The biological properties of the extracted phenolics were analyzed in vitro using 1,1-diphenyl-2-picryl-hydrazyl assays, enzyme-linked immunosorbent assays, angiotensin-1 converting enzyme assays, and α-amylase assays. The free and bound phenolic compounds were identified using liquid chromatography electrospray ionization tandem mass spectrometry methods. The aromatic rings in globulin were the highest in both before and after the removal of phenolic compounds (1.13 and 1.05 mg/g). The highest values of angiotensin-1 converting enzyme inhibitory and α-amylase inhibition (%) were obtained in glutelin-1 (73.17 and 96.41%, respectively) before removal phenolic compounds. The biological activity was affected by the presence or absence of phenolic compounds. Allergenicity was minimized in the presence of phenolic compounds. Correlation coefficients between wheat protein fractions and biological properties are described.

This research aimed to determine the biofunctional properties of wheat flour (WF) protein fractions and modifications to the antioxidant, anti-α-amylase and anti-angiotensin-I converting enzyme (ACE) activities induced by the action of digestive endopeptidases in vitro. A molecular characterization of the most abundant protein fractions, i.e., albumins, glutelins-1, glutelins-2 and prolamins, showed that low- and high-MW polypeptides rich in cysteine, glutamic acid and leucine were present in albumins and glutelins, whereas low-MW subunits with a high proportion of polar amino acids prevailed in prolamins. Prolamins exhibited the second-highest water holding capacity (54%) after WF (84%), while albumins provided superior foam stability (76%). Prolamins, glutenins-1 and globulins demonstrated the highest antioxidant activity (up to 95%, 68% and 59%, respectively) both before and after hydrolysis with pepsin (P-H) or trypsin–chymotrypsin (TC-H). Prolamins, globulins and WF strongly inhibited α-amylase (>90%) before and after TC-H, and before P-H (55–71%). Moreover, P-H significantly increased α-amylase inhibition by albumins from 53 to 74%. The fractions with strong ACE inhibitory activity (70–89%) included prolamins and globulins after TC-H or P-H, as well as globulins before TC-H and WF before P-H. This novel evidence indicates that WF protein fractions and their peptide-enriched P and TC hydrolysates are excellent sources of multifunctional bioactives with antioxidant, antihyperglycemic and antihypertensive potential.

In recent years, there has been a growing interest in developing a distinguished alternative to human consumption of animal-based proteins. The application of lentil proteins in the food industry is typically limited due to their poor solubility and digestibility. An innovative method of balancing lentil-whey protein (LP-WP) complexes with higher-quality protein properties was established to address this issue, which coupled a pH-shifting approach with fermentation treatment. The results showed that microorganisms in the water kefir influenced the quality of protein structures and enhanced the nutritional values, including increasing the total phenolic compounds and improving the flavor of fermented LP-WP complexes. The protein digestibility, pH values, microbial growth, total soluble solids, and total saponin and phenolic contents were hydrolyzed for 5 days at 25 °C. The FTIR spectrophotometer scans indicated significant (P < 0.05) changes to the secondary protein structure components (random coil and α-helix). This study showed that combining pH-shifting with fermentation treatment improves lentil and whey proteins’ structure, protein quality, and nutritional benefits.

Pomegranate juice (PJ) is the major pomegranate product that offers a simple way to consume pomegranate’s biologically active compounds, obtained from arils. In this study, we objectively investigate the physiochemical properties such as pH value, total soluble solids, color parameters, fructose and glucose contents, hydroxymethyl furfural (HMF) content, and viscosity. Also, the phytochemical content includes total phenols content, antioxidant activity, flavonoid, anthocyanin content, and phenolic quantification. In addition, the alpha-amylase and angiotensin-converting enzyme inhibitory activities among sweet and sour varieties of pomegranate juice obtained from different regions in Northern Jordan (Ajloun, Dair Abi Said, and Kufur Soum) where the significant differences at ≤ 0.05 appeared among sweet and sour varieties in different pomegranate juice samples. The pH values for pomegranate juice range from 2.87 to 3.77, and TSS ranges from 15.36 to 16.9 Brix. The total phenol content of pomegranate juice ranged from 105.8 to 238.63 mg/g while the total flavonoid content was present in the range of 135.53–184.9 mg/g. The DPPH inhibition (%) of pomegranate juice ranged between 20.66% and 50.63%, and the anthocyanin content range was 3.66–11.02 mg/g. Ellagic acid, delphinidin, 3,4-dihydroxyphenethyl alcohol, 2-hydroxyphenethyl alcohol, catechin, epicatechin, vanillic acid, caffeic acid, P-coumaric acid, chlorogenic acid, gallic acid, ferulic acid, and syringic acid are phenolics present predominantly in pomegranate juice. Pomegranate juice exhibits high alpha-amylase and angiotensin-converting enzyme inhibition activity. All results indicate good quality and health properties for pomegranate juice.

Lupin is an agriculturally economical plant seed. It is considered a rich source of protein for both humans and animals in several regions of the world. Lupin proteins also could act as an encapsulation agent for vitamins and other nutritional factors after extraction. This research evaluated the effects of microwave and ultrasound extraction methods on sweet and bitter lupin proteins intended to act as encapsulation agents. Two distinct sizes of nanoparticles were detected using different types of treatments. Bitter lupin was optimal for generating large nanoparticles, while sweet lupin was optimum for generating small nanoparticles. Ultrasound treatment of bitter lupin after microwave treatment hydrolyzed some of the β-conglutin, which suggested a method to reduce the potential allergic reactions caused by lupin products. The total phenolic content and alpha-amylase inhibitory effect of sweet and bitter lupin proteins was high. Furthermore, the microwave extraction method showed the benefits of reduced solvent consumption and less time. The current results showed a positive effect of the combined application of ultrasound-assisted and microwave-assisted processes on the nutraceutical and functional properties of lupin protein extracts.