Effect of oven roasting treatment on the antioxidant activity, phenolic compounds, fatty acids, minerals, and protein profile of Samh (Mesembryanthemum forsskalei Hochst) seeds

The thermal degradation of glucomoringin and changes of phenolic compounds in moringa seed kernels during different degrees of roasting

The effect of heat treatment on the abundant bioactive compounds in moringa seed kernels (MSKs) during different degrees of roasting remains sparingly explored despite the flour of roasted MSKs has been incorporated into the human diet (e.g., cakes, cookies, and burgers) as a substitute to enrich the nutritional content. Therefore, we investigated the impacts of different roasting conditions (e.g., temperature and duration) on bioactive compounds (e.g., glucosinolates (GSLs), phenolic acids and alkaloids) and antioxidant capacity of MSKs. Our results showed that light and medium roasting increased the glucomoringin (GMG, the main GSL in MSKs) content from 43.7 (unroasted MSKs) to 69.7-127.3 μmol/g MSKs (dry weight), while excessive/dark roasting caused thermally-induced degradation of GMG (trace/undetectable level) in MSKs, resulting in the formation of various breakdown products (e.g., thiourea, nitrile, and amide). In addition, although roasting caused a significant reduction of some phenolic compounds (e.g., gallic, chlorogenic, p-coumaric acids, and trigonelline), other phenolic acids (e.g., caffeic and ferulic acids) and alkaloids (e.g., caffeine, theobromine, and theophylline) remarkably increased after roasting, which may contribute to the enhanced total phenolic content (up to 2.9-fold) and antioxidant capacity (up to 5.8-fold) of the roasted MSKs.

Effect of different physical pre-treatments on physicochemical and techno-functional properties, and on the antinutritional factors of lentils (Lens culinaris spp)

Lentils have a valuable physicochemical profile, which can be affected by the presence of antinutrients that may impair the benefits arising from their consumption. Different treatments can be used to reduce these undesirable compounds, although they can also affect the general composition and behaviour of the lentils. Thus, the effect of different processing methods on the physicochemical and techno-functional properties, as well as on the antinutritional factors of different lentil varieties was studied. Phytic acid was eliminated during germination, while tannins and trypsin inhibitors are mostly affected by cooking. Functional properties were also altered by processing, these being dependent on the concentration of different nutrients in lentils. All the studied treatments affected the physicochemical profile of lentils and their functional properties. Cooking and germination appear to be the most effective in reducing antinutritional factors and improving the physicochemical profile of the lentils, meeting the current nutritional demands of today's society.

Chemosensory of hemp seed oil extracted with hemp seed(Cannabis sativa L.) roasted under various conditions using electronic sensors and GC-MS/Olfactometry

This study analyzed the flavor of six types of hemp seed oil (HSO) extracted with roasted hemp seed (RHS) under various conditions (Raw, 140 °C_9 min, 140 °C_12 min, 160 °C_12 min, 180 °C_6 min). Electronic tongue (E-tongue), electronic nose (E-nose), GC-MS (gas chromatography-mass spectrometry), and GC-O (gas chromatography-olfactometry) were used for HSO flavor analysis. As a result of the E-tongue analysis, the sweetness tends to increase in most samples as roasting. A total of 89 and 77 volatile compounds were detected through E-nose and GC-MS, and the main volatile compounds were identified as Maillard reaction products. A total of 16 odor active compounds were detected in the GC-O analysis, and in the case of 160 ℃_12 min and 180 ℃_6 min, the scent of Roasted hemp seed oil was more dominant than other aroma profiles. The results of this study are basic data on the flavor characteristics of HSO.

The Effect of Germination and Fermentation on the Physicochemical, Nutritional, and Functional Quality Attributes of Samh Seeds

This study investigated the effects of fermentation and germination on the physicochemical, nutritional, functional, and bioactive quality attributes of samh seeds. Regardless of the processing treatment, samh seeds were found to be a rich source of phenolic compounds, namely gallic acid (79.6-96.36 mg/100 g DW), catechol (56.34-77.34 mg/100 g DW), and catechin (49.15-84.93 mg/100 g DW), and they possessed high DPPH antiradical activity (65.27-78.39%). They also contained high protein content (19.29-20.41%), essential amino acids content (39.07-44.16% of total amino acids), and unsaturated fatty acid content (81.95-83.46% of total fatty acids) and a low glycemic index (39.61-41.43). Fermentation and germination increased L*, b*, foaming capacity, oil absorption capacity (OAC), water absorption capacity (WAC), swelling power, microbial counts, antioxidant activity, total flavonoid content (TFC), total phenolic content (TPC), in vitro protein digestibility, protein efficiency ratio, and total essential amino acids and reduced water solubility, emulsion stability, tannin, and phytate contents compared to raw samh seeds (p < 0.05). The highest levels of pH, ash, carbohydrate, fiber, and glycemic index were observed in raw samh seeds, and both germination and fermentation processes reduced these attributes to various degrees (p < 0.05). Germination increased the redness (a*), moisture content, essential and non-essential amino acids, potassium, zinc, phosphorous, stearic acid, and oleic and unsaturated fatty acids and reduced total solids, fat content, iron, zinc, calcium, magnesium, sodium, palmitic acid, and total saturated fatty acids of the samh seeds compared to the raw ones. Fermentation increased the total solid, acidity, fat, protein, calcium, magnesium, sodium, phosphorous, iron, zinc, palmitic acid, and total saturated fatty acids and reduced the a* value, moisture, non-essential amino acids, and total unsaturated fatty acids of the samh seeds compared to the raw ones. In conclusion, samh seeds are a rich source of nutrients that could generally be enhanced by germination and fermentation processes. The reported information facilitates strategies towards the application of these underutilized seeds in foods.

Effects of roasting and ultrasound-assisted enzymatic treatment of Nigella sativa L. seeds on thymoquinone in the oil and antioxidant activity of defatted seed meal

BACKGROUND

Black cumin seeds (black seed; BS) contain various bioactive compounds, such as thymoquinone (TQ). Roasting and ultrasound-assisted enzymatic treatment (UAET) as pre-treatments can increase the phytochemical content in the BS oil. This study aimed to investigate the effects of pre-treatments on the TQ content and the yield of the BS oil and to profile the composition of defatted BS meal (DBSM), followed by evaluating antioxidant properties of the DBSM.

RESULTS

The extraction yield of crude oil from BS was not affected by the roasting time. The highest extraction yield (47.8 ± 0.4%) was obtained with UAET cellulase-pH 5 (enzyme concentration of 100%). Roasting decreased the TQ content of the oil, while the UAET cellulase-pH 5 treatment with an enzyme concentration of 100% yielded the highest TQ (125.1 ± 2.7 μg mL-1 ). Additionally, the UAET cellulase-pH 5 treatment increased total phenolics and flavonoids of DBSM by approximately two-fold, compared to roasting or ultrasound treatment (UT) alone. Principal component analysis revealed that the UAET method might be more suitable for extracting BS oil with higher TQ content than roasting and UT.

CONCLUSION

Compared to roasting or UT, using ultrasound along with cellulase could improve the oil yield and TQ in the oil from BS and obtain the DBSM with higher phenolics, flavonoids, and antioxidant activity. © 2023 Society of Chemical Industry.

Effect of Vacuum Roasting on Total Selenium Content of Selenium-Enriched Rapeseed, Maillard Reaction Products, Oxidative Stability and Physicochemical Properties of Selenium-Enriched Rapeseed Oil

Selenium-enriched rapeseed (SER) is an emerging oil seed. Roasting is beneficial in improving oil yield and promoting the release of micronutrients into SER oil, but high temperatures and dry air lead to selenium loss and fatty acid degradation in SER. To minimize the selenium loss and improve the SER oil quality, this study investigated the effects of vacuum (VC) roasting (90-170 °C for 30 min) on the SER selenium content, Maillard reaction products, oxidative stability, and physicochemical properties of SER oil, with conventional dry air (DA) roasting as the control. The results showed that the selenium loss in VC-roasted SER meals increased from 7.17 to 19.76% (90-170 °C for 30 min), which was 47.13 to 80.48% of that in DA-roasted SER meals, while no selenium was detected in the SER oils. Compared to DA roasting, VC roasting (90-170 °C for 30 min) reduced lipid oxidation products (LOPs), Maillard reaction products (MRPs), and benzo[a]pyrene contents, and increased carotenoids, unsaturated fatty acid contents, reaching a maximum oil yield of 35.58% at a lower temperature (130 °C for 30 min). Selenium contents exhibited a highly significant negative correlation with MRPs and LOPs (p ≤ 0.005). The VC roasting retarded selenium loss and improved SER oil quality compared to conventional DA roasting.

Evaluation of Roasting and Grilling Effects on Chemical Composition, Volatile Profiles, and Toxicity of Stink Bugs (Tessaratoma papillosa): Implications for Utilization as Functional Food Ingredients

The stink bug (Tessaratoma papillosa) is a highly popular edible insect in Thai traditional cuisine, but little research has investigated the effects of heat treatment on the quality of stink bugs. Therefore, we aimed to evaluate the effects of roasting and grilling on the chemical changes and volatile compounds of late nymph and adult stink bugs. In general, all treated samples showed increases in phenolic acid, tocopherols, and amino acid contents and a decrease in the content of fiber compared with raw stink bugs (p < 0.05). Cinnamic acid significantly increased by over 200% in late nymph insects and 30% in adult insects after roasting, whereas syringic acid decreased after cooking (p < 0.05). The most predominant volatile compound found in all samples was 5-methyl-octadecane and it decreased after cooking, while volatile alkane compounds increased after cooking. The processed sample extracts showed higher toxicity on oral cancer KB and cervical cancer Hela cells than on Vero cells. We have demonstrated that different cooking methods affected the chemical components which may result in quality attributes if stink bug is to be used as a functional ingredient/food. It may be helpful to improve the nutritional and functional values of stink bugs during deep processing.

Clove Polyphenolic Compounds Improve the Microbiological Status, Lipid Stability, and Sensory Attributes of Beef Burgers during Cold Storage

This study investigated the phenolic composition of clove powder extract (CPE), determined by high-pressure liquid chromatography, as well as the effect of the clove powder (CP) concentration (0, 2, 4, and 6%) on the quality of beef burgers during 21 days of cold storage at 4 °C. The CPE contained a high amount of total phenolic content (455.8 mg Gallic acid equivalent/g) and total flavonoid content (100.4 mg catechin equivalent/g), and it exhibited high DPPH antioxidant scavenging activity (83.9%). Gallic acid, catechol, and protocatechuic acid were the highest phenolic acids (762.6, 635.8, and 544.9 mg/100 g, respectively), and quercetin and catechin were the highest flavonoid acids (1703.1 and 1065.1 mg/100 g, respectively). Additionally, the CPE inhibited the growth of both Gram-positive and Gram-negative bacteria effectively at 100 μg/disc. The addition of the CP had no discernible influence on the pH of the meat patties. The addition of CP at 4 and 6% increased the phenolic content and antioxidant activity of the beef patties, which consequently resulted in reduced lipid oxidation and microbial spoilage throughout the storage period. Furthermore, the CP significantly (p ≤ 0.05) improved the beef burger cooking characteristics (cooking yield, fat retention, moisture retention, and shrinkage). Additionally, the sensory acceptability was higher (p ≤ 0.05) for the burgers that contained 2% and 4% CP compared with the other treatments. In conclusion, the bioactive compounds in CP can extend the shelf life and improve the safety of beef burgers.

Antioxidant Activity, Phenolic Composition, and Hormone Content of Wild Edible Vegetables

Wild edible plants have been used since antiquity as folk medicine and as preservatives in foods. This study aimed to determine the antioxidant activities, phenolic compounds, and hormone contents of 12 species of edible wild plants belonging to 9 families, which are consumed as vegetables by the local people at Ergan Mountain in Erzincan in Turkey. Polygonum cognatum and Malva neglecta were determined to have more antioxidant enzyme activity, more phenolic compounds, and higher hormone content than the other species. The highest catalase (CAT), peroxidase (POD), glutathione reductase (GR), glutathione-s-transferase (GST) values for P. cognatum were determined as 45.12, 94.83, 36.76, and 1218.35 EU g−1, respectively. The highest superoxide dismutase (SOD) and ascorbate peroxidase (AxPOD) content for M. neglecta were determined as 97.53 EU g−1 and 81.93 EU g−1, respectively. P. cognatum is the species in which the highest levels of the hormones indolacetic acid (IAA), gibberellic acid (GA), salicylic acid (SA), cytokinin, zeatin and jasmonic acid were detected. The highest levels of caftaric acid (CA), catechin (CAE), ferulic acid (FA), malvidin-3-o-glucoside (MG), myricetin (MYR), rutin (RT), trans-coumaric acid (TPCA), tyrosol (TY), and vanilic acid (VA) compounds were found in M. neglecta. It was determined that Falcaria vulgaris species had the highest levels of ferulic acid (FA) and quercetin (QUE) phenolics. The results show that edible wild vegetables consumed and studied by the people of the region are an important source of natural antioxidants. The possibilities of using these wild plants as functional foods should be investigated.

Effects of roasting on bioavailability and bioactivities of Vigna angularis and potential of coffee-like beverage

Containing similar aroma and flavor profile of coffee after roasting, Vigna angularis have potential to be a caffeine-free coffee-like beverage. Microwave roasting process was conducted in a microwave oven at 600 W for 7, 14, and 21 min at 2-min intervals, and fluidized bed roasting process was conducted in a fluidized bed roaster at 200°C for 9, 18, and 27 min. In order to compare the roasted beans, color, fat, ash, crude protein, crude fiber, antioxidant activity, and total phenolic content measurements were performed. In addition, effects of roasting methods on protein bioavailability and antinutritional factors were investigated. Sensory test was conducted to compare the coffee and coffee-like beverages. Fluidized-bed roasted beans had higher scores than microwave roasted beans in terms of sensory acceptability (p ≤ 0.05). Roasting process increased the total phenolic contents up to 25.32 (mg GAE/g) and the protein bioavailability up to 89.82 ± 0.11%. The results of this study revealed that roasting can be used as a tool to increase nutritive value, bioavailability, antioxidant activity, and potential of coffee-like beverage of V. angularis. PRACTICAL APPLICATION: Since Vigna angularis beans contain similar aroma and flavor profile of the coffee after roasting, they have a potential to be a caffeine-free coffee alternative. Although coffee is very popular in demand, most of the coffee drinkers think that caffeine is very harmful. Having similar sensory scores as coffee beverages in certain roasting degrees, V. angularis beverages could be a delicious caffeine-free alternative.

Effects of Boiling and Roasting Treatments on the Content of Total Phenolics and Flavonoids and the Antioxidant Activity of Peanut (Arachis hypogaea L.) Pod Shells

This study was conducted to investigate the effect of boiling and roasting treatments on the phenolic and flavonoid contents and antioxidant activity of pod shells of two Sudanese peanut cultivars, Sodari and Ghabiash. The samples were subjected to a boiling process (1:5 w/v; 20 g/100 mL) at 100 °C for 45 min and a roasting treatment at 180 °C for 30 min. Results revealed that both cultivars are rich in phenolic compounds with high antioxidant activity in their shell. The boiling and dry roasting treatments significantly (p < 0.05) enhanced the total phenolic content, total flavonoid content, and antioxidant activity of the peanut shell for both peanut cultivars. The shells of Ghabiash peanut cultivar exhibited higher bioactive properties than the shells of Sodari cultivar, in which these properties were highly improved by roasting and boiling treatments. In general, peanut shells can serve as an important underutilized by-product, particularly after roasting treatment, for potential applications in food formulations.

Effect of roasting on the chemical composition, functional characterisation and antioxidant activities of three varieties of marble vine (Dioclea reflexa): An underutilised plant

Marble vine (Dioclea reflexa) seeds were roasted using the conditions in runs generated from Response Surface Methodology with temperature ranging from 110 to 200 °C and time (10–40 min). Proximate composition, antioxidant activities (DPPH, ABTS, FRAP, metal chelation OH and Lipid peroxidation) and Fourier Transform Infrared Spectroscopy (FTIR) were carried out on unroasted and roasted flours. Roasting increased the crude fibre content (2.74–5.08 %) of black variety compared to others. However, a slight denaturation of protein was observed when compared to unroasted samples. A significant increase in all the antioxidant activities compared to the control was also observed compared to unroasted flours. The FTIR showed functional groups such as ketones, aldehydes and carbonyl group upon roasting. Roasting temperature at (110 °C) had more effect than roasting time (10, 25 and 40 min). Hence, roasting at 110 °C could enable the release of food nutrients and improve the functionality of marble vine seed flour.

Effect of Roasting on the Antioxidant Activity, Phenolic Composition, and Nutritional Quality of Pumpkin (Cucurbita pepo L.) Seeds

In recent years, with the increasing awareness of health concerns and environment protection needs, there is a growing interest for consumers to choose plant-based food diets compared with those made from animal origin. Pumpkin seed is an excellent dietary source for protein, oil, and some essential micronutrients. Raw pumpkin seed may have a compromised flavor, color, as well as digestibility. Therefore, the objective of present study is to study the influence of roasting (120, 160, and 200°C for 10 min) on the phenolics content, flavonoids content, antioxidant property, fatty acids, and volatile matter composition, as well as protein profile of pumpkin seeds. Our results indicated that, total phenolic compounds, total flavonoids content, as a consequence, total antioxidant capacity increased as the roasting temperature increased. Maillard reaction products and lipid peroxidation products were identified, especially from those pumpkin seeds roasted at high temperature. In the meantime, the composition and content of fatty acids did not change significantly after roasting. The results of electrophoresis and particle size analysis showed that the optimum roasting temperature was 160°C to obtain protein with better nutritional quality. The findings of this study may contribute to the utilization of pumpkin seed component in plant-based diets with increased nutritional quality.

Effect of conventional oven roasting treatment on the physicochemical quality attributes of sesame seeds obtained from different locations

The impacts of conventional oven roasting at different temperatures and for different times on the physicochemical attributes of sesame seeds obtained from different regions was assessed. The color characteristics (a*, b*, and L* values), ash, moisture, protein, oil, total phenolic, and antioxidant activity of raw sesame seeds and the peroxide value, p-anisidine, fatty acids, and tocopherols of sesame oil varied with source. Oven roasting temperature and time significantly affected the physicochemical properties and bioactive components of sesame seeds and the oil quality from different countries. Roasting variably increased the a* value, antioxidant activity, protein, oil, total phenolic, and tocopherol content, and p-anisidine and peroxide values, whereas it reduced b* and L* values, moisture, and linolenic acid content of sesame seeds from different countries. Roasting conditions and growing locations affected the physiochemical composition and bioactive compounds of seeds. Such factors can influence the quality attributes of sesame seeds and oil and should be considered during processing.