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Mushrooms are health foods due to their nutritional values and antioxidant properties. This study investigated chemical properties, total phenolic content (TPC), antioxidant activities (2, 2-diphenyl-1-picrylhydrazyl; DPPH and 2, 2-azino-bis-(3-ethylbenzothiazoline-6-sulfonic acid); ABTS) and selected phenolic acids from five different tray-dried and freeze-dried mushrooms (Pleurotus ostreatus, Pleurotus pulmonarius, Schizophyllum commune, Volvariella volvacea and Lentinus edodes). The extracts were prepared using methanol and hot water extractions. The results revealed that V. volvacea had the highest protein (28.70%) and ash (9.48%) contents. There were significant differences among some tray dried and freeze dried mushrooms regarding TPC, DPPH and ABTS. However, tray drying tended to improve TPC, DPPH and ABTS in P. ostreatus, P. pulmonarius and L. edodes. Among five mushroom species, both methanol and hot water extractions of V. volvacea had the highest TPC, DPPH and ABTS values but there were no significant differences between mushrooms prepared using tray drying and freeze drying. Moreover, the yield and contents of gallic acid and p-hydroxybenzoic acid from the hot water extracts were higher than from the methanol extracts. Therefore, tray-dried V. volvacea had the most potential as a natural antioxidant and could be used as a functional ingredient in healthy food products.

Effects of mushroom type, seasoning and health benefit information (HBI) on consumers’ saltiness expectation, sensory liking, elicited emotions and purchase intent (PI) of extruded snacks were investigated. Five snacks were evaluated: straw mushroom (Volvariella volvacea) extrudates without (SME) or with seasoning (SMES), phoenix mushroom (Pleurotus pulmonarius) extrudates without (PME) or with seasoning (PMES), and the control without mushroom and seasoning. Hedonic scores and positive emotions were generally higher for seasoned mushroom‐containing snacks (SMES and PMES) with 65% and 75.83% of consumers reporting willingness to purchase, respectively, after receiving HBI. Bored, interested and satisfied were identified as significant emotional predictors for PI odds. Flavour, saltiness, overall liking, bored, good and interested were critical attributes, differentiating snacks. This study demonstrated that sensory liking and PI of extruded brown rice‐based snacks containing mushroom could be improved through savoury seasoning addition, which also allowed saltiness expectations to be met.

The effects of three levels of pumpkin flour (PF; 10, 20 and 30%) and three levels of feed moisture content (FM; 13, 16 and 19%) on the physical properties, antioxidant activity and sensory properties of pumpkin-germinated brown rice extrudates were investigated. The increase in the PF increased the bulk density, hardness, total phenolic content (TPC) and antioxidant activity, but decreased the expansion ratio of the extruded snack. Decreasing the FM caused an increase in the TPC and antioxidant activity of the snack product. The predicted optimum formulation of extrudates using response surface methodology was 10–13% PF and 13–14% FM under extrusion conditions at 140 °C (zone 6) and 350 rpm screw speed. These conditions produced extruded snacks with TPC values of 20–28 mg GAE/100 g sample on a dry basis and appearance and hardness liking scores of more than 6.5 (on a 9-point hedonic scale). Therefore, the results of this study supported the utilization of PF and germinated brown rice flour to develop healthy snack products. Keywords: Antioxidant activity, Extrusion, Germinated brown rice flour, Pumpkin flour, Snack

Dried squid head is an abundant–low value by product from dried squid snack industry. The head is consisted of high protein content with the abundant sweet-umami amino acid, glutamic acid (7.45 mg/100 mg). The major volatile compounds found are trimethylamine and toluene along with the 15 important compounds exhibited dried squid flavor. Enzymatic hydrolysis with Flavourzyme® was performed at the optimal pH and temperature in order to produce flavored-functional protein hydrolysate. The supernatant was collected at 0, 30, 60, 90, 120, 150, 180 and 210 min of hydrolysis. The sweet-umami hydrolysate solution with the highest liking score at 6.64 was obtained after 180 min of hydrolysis. This sample was subjected to dry using freeze drying and foam-mat drying and investigated the changes of flavor compounds and functional properties. The freeze dried sample had umami taste and light brown color, and possessed the various types of volatile compounds. It contained protein at 76.42%, and EAI at 22.00, while the foam-mat dried sample had the highest ESI (15.27) and FS (29.87). The antioxidant property of the freeze dried sample (ABTS scavenging activity at 14.77 mg/g, FRAP scavenging activity at 5.93 mmol Fe2SO4 7H2O/g and DPPH scavenging activity at 19.51%, respectively) was higher than that of the foam-mat dried sample. Hence, it could be used as flavored-functional ingredient in foods.

Summary Physicochemical properties (pasting and thermal properties, swelling power, water solubility and antioxidant activities) and chemical composition of pumpkin flour (PF) and starches, isolated from fresh pumpkin (SFF) or flour (SFP) were compared. SFP and SFF had similar proximate composition and amylose content. Drying process during PF preparation modified starch properties. PF exhibited greater antioxidant activities (DPPH, ABTS and FRAP), but had lower β-carotene than fresh pumpkin. SFF and SFP had higher amylose content than PF, and exhibited a B-type X-ray diffraction pattern with spherical and dome-like starch granules. Peak viscosity of SFP was relatively higher than that of SFF, probably due to lower swelling power and water solubility, which indicated increased granular rigidity in the SFP starch structure. Compared with SFF and SFP, PF had significantly higher onset (To), peak (Tp) and conclusion (Tc) temperatures due to a lower starch content and relatively higher fibre content, which resulted in lower gelatinisation enthalpy (ΔH).

The effects of the enzyme type (Alcalase, Flavourzyme and Neutrase) and hydrolysis time (2, 4 and 6 h) on properties of rice bran protein hydrolysate (RBPH) were studied. The enzyme type had significant effects on the protein yield and the properties of RBPH whereas the hydrolysis time was less influence. There were small differences in the total phenolic content and the ABTS radical scavenging activity between protease-hydrolyzed and unhydrolyzed rice bran protein, but enzymatic hydrolysis using Alcalase was the most effective providing hydrolysate with the highest protein yield and protein content. The optimal hydrolysis conditions was 2 h using an Alcalase-yielding protein content of 30.3%, a protein yield of 56.6%, TPC of 22.1 mg GAE/g, ABTS of 7.57 mg GAE/g and FRAP of 152 mM Fe 2+ /g. Fractionated peptides from this hydrolysate using anion exchange chromatography showed high antioxidant activity containing both positive and negative charge fractions with a low M W of 6 kDa. The RBPH using Alcalase could be a protein source and antioxidant in functional foods and beverages.

Summary Protein hydrolysate from pigmented Riceberry rice bran has great potential to be used in food products due to its protein content and antioxidative activities. In this study, characteristics, solubility, heat stability and emulsification properties of protein hydrolysates from the bran fraction of two rice cultivars, commercial rice bran (CBH) and Riceberry bran (RBH), were investigated. Both CBH and RBH showed the lowest solubility near their isoelectric point between pH 2 and 3. Solubility of RBH increased with increasing pH as the hydrolysates became more negatively charged; however, solubility of CBH was less dependent on pH. Heating did not significantly affect solubility of both hydrolysates which could be due to reduced aggregation of low-molecular weight peptides and/or the exposure of charged and polar groups after hydrolysis. Oil-in-water emulsions stabilised by RBH were more stable compared to those stabilised by CBH. Maximum stability was achieved with RBH at pH 6 where no creaming was observed after 14 day storage. Higher stability could be due to increased surface protein coverage, more negative charge and higher viscosity of RBH-stabilised emulsions. In addition, higher carbohydrate content and the presence of flavonoid could also contribute to an increase in stability. These results can be applied in food products using rice bran protein hydrolysate as nutritional ingredients.

Rice bran oil (RBO) is used in several products in the food, cosmetics, and pharmaceutical industries due to its desirable health, flavor, and functional attributes. The formation and physicochemical properties of microencapsulated RBO stabilized by different biopolymers were investigated. Oil-in-water emulsions (10% RBO, citrate buffer pH 7) stabilized by either 3.5% whey protein isolate (WPI) or 7.0% modified starch (MS) containing maltodextrin (DE18) as a carrier agent were initially prepared. The diameter of emulsion droplets produced by WPI and MS were considerably smaller than 300 nm and 25 μm for dried particles. The resulting powders had poor to fair flowability and high cohesiveness characteristics: Carr index (27–37) and Hausner ratio (1.4–1.6). The microencapsulation efficiency of the spray-dried powders ranged from 92–95%. Moisture sorption isotherms of the powders were determined by a gravimetric method, while their glass transition temperatures (Tg) were determined by differential scanning c...

Food and Applied Bioscience, 3, 2, 160-172