Antioxidant properties of several commercial mushrooms

Winter (strains white and yellow), shiitake (strains 271 and Tainung 1) and oyster mushrooms (abalone and tree oyster mushrooms) were obtained commercially and methanolic extracts were prepared from these mushrooms and their antioxidant properties were studied. The antioxidant activities by the 1,3-diethyl-2-thiobarbituric acid method were moderate to high at 1.2 mg ml⁻¹. Reducing powers were excellent (and higher than 1.28 absorbance) at 40 mg ml⁻¹. Scavenging effects on 1,1-diphenyl-2-picrylhydrazyl radicals were moderate to high (42.9–81.8%) at 6.4 mg ml⁻¹. With regards to the scavenging effect on hydroxyl free radicals, tree oyster mushrooms were the highest (54.3%) at 40 mg ml⁻¹ whereas other commercial mushrooms were low. Chelating effects on ferrous ions were 45.6–81.6% at 1.6 mg ml⁻¹. Total phenols were the major naturally occurring antioxidant components found. Overall, tree oyster mushrooms were better in antioxidant activity, reducing power and scavenging abilities and higher in total phenol content.     

Non-volatile components of several medicinal mushrooms

Three species of medicinal mushrooms are commercially available in Taiwan, including Ling Chih (Ganoderma lucidum), Sung Shan Ling Chih (Ganoderma tsugae) and Yun Chih (Coriolus versicolor). The objective of this study was to examine the non-volatile components in these medicinal mushrooms, including their proximate compositions, soluble sugars, free amino acids and 5′-nucleotides. Ganoderma spp. contained 7.18–7.92% of proteins and Yun Chih contained 4.20%. Carbohydrate contents showed two different levels, Yun Chih (65.09%) and Ganoderma spp. (21.83–27.78%). The fiber contents were in the order of Sung Shan Ling Chih (65.29%), regular and antler Ling Chih (59.16 and 59.49%, respectively), and Yun Chih (23.24%). Yun Chih contained 20.21 mg g⁻¹ dry weight of total soluble sugars whereas Ganoderma spp. contained low amounts. Total free amino acid contents ranged from 4.25 to 14.04 mg g⁻¹. Contents of MSG-like components ranged from 0.17 to 0.50 mg g⁻¹ and sweet components ranged from 0.28 to 1.38 mg g⁻¹. The bitter components were predominantly present in these mushrooms. Contents of total and flavour 5′-nucleotides were high in Yun Chih and Ling Chih. The umami intensities were expected to be in the descending order of Ling Chih, Yun Chih, Sung Shan Ling Chih and antler Ling Chih.     

Non-volatile taste components of Agaricus blazei,Antrodia camphorata and Cordyceps militaris mycelia

Three non-Ganoderma medicinal mushrooms are currently popular in Taiwan, including Brazilian mushroom (Agaricus blazei), chang-chih (Antrodia camphorata) and northern caterpillar fungus (Cordyceps militaris). The moisture contents of three dry mycelia ranged widely from 6.65 to 14.91%. All mycelia were high in carbohydrate content with chang-chih being the highest. The protein contents ranged from 9.49 to 29.1%. Soluble sugars found were arabitol, glucose and trehalose, and the contents exceeded 10%. Total free amino acid contents ranged from 7.01 to 11.1 mg g⁻¹ dry weight. Contents of monosodium glutamate-like components were relatively low and similar in Brazilian mushroom and chang-chih, but high in northern Cordyceps. Contents of bitter components were significantly high in Brazilian mushroom and northern Cordyceps. Contents of flavour 5′-nucleotides were similarly high in chang-chih and northern Cordyceps, and low in Brazilian mushroom. The three mushroom mycelia had different proximate compositions. However, northern Cordyceps and chang-chih might exhibit similar umami and sweet tastes.     

Non-volatile taste components of several speciality mushrooms

Four speciality mushrooms are commercially available in Taiwan, including Dictyophora indusiata (basket stinkhorn), Grifola frondosa (maitake), Hericium erinaceus (lion's mane), and Tricholoma giganteum (white matsutake). Protein contents ranged from 14.6 to 22.3%. Carbohydrate contents were high in basket stinkhorn and white matsutake (67.0 and 70.1%) and low in maitake and lion's mane (58.8 and 57.2%, respectively). Contents of total soluble sugars showed two distinct levels, white matsutake (349 mg g⁻¹) and other mushrooms (153–188 mg g⁻¹). Total free amino acid contents ranged from 7.41 to 12.3 mg g⁻¹. Contents of monosodium glutamate-like components ranged from 0.68 to 1.09 mg g⁻¹. Contents of flavor 5′-nucleotides were high in white matsutake, moderate in basket stinkhorn, and low in lion's mane and maitake. In this study, the four speciality mushrooms, in addition to their characteristic appearances, were distinctly different in both their proximate compositions and their taste components.     

Non-volatile taste components of Agaricus blazei, Agrocybe cylindracea and Boletus edulis

Three species of dried mushrooms are commercially available in Taiwan, namely Agaricus blazei (Brazilian mushroom), Agrocybe cylindracea (black popular mushroom) and Boletus edulis (king bolete), and their non-volatile taste components were studied. All mushrooms were high in contents of carbohydrate, crude fiber and protein but low in contents of crude ash and fat. Arabitol, myo-inositol, mannitol and trehalose were detected in these three mushrooms, whereas glucose was not found in B. edulis. Contents of total soluble sugars and polyols ranged from 150.33 to 225.08 mg/g. Total free amino acid contents were low in these three mushrooms and ranged from 8.97 to 14.91 mg/g. The contents of MSG-like components ranged from 1.24 to 4.40 mg/g were in the descending order of the A. blazei, A. cylindracea and B. edulis. Total 5′-nucleotides contents of A. blazei and A. cylindracea were higher than that of B. edulis whereas flavor 5′-nucleotides content of A. blazei was higher than those of A. cylindracea and B. edulis. Equivalent umami concentrations values in three mushrooms ranged from 10.46 to 135.90 g per 100 g. Overall, these three mushrooms possessed highly umami taste.     

Contents of sugars,free amino acids and free 5′-nucleotides in mushrooms,Agaricus bisporus,during post-harvest storage

Common mushrooms, Agaricus bisporus (Lange) Imbach, were stored at 12 °C for 12 days and composition changes were examined during post-harvest storage. The contents of total sugars, mannitol and fructose decreased steadily during storage, whereas the content of other reducing sugars, excluding fructose, remained constant. The content of total free amino acids increased from 77.92 at day 0 to 140.57 g kg⁻¹ at day 6, and then slightly increased to 151.65 g kg⁻¹ at day 12. The contents of nine amino acids increased over time, of these glutamic acid was the most significant. The content of monosodium glutamate-like components increased from 22.67 at day 0 to 47.12 g kg⁻¹ at day 12. However, the contents of sweet and bitter components increased comparably from 24.08 and 24.17 at day 0 to 47.15 and 50.75 g kg⁻¹ at day 12, respectively. Total 5′-nucleotide content peaked at day 3. The contents of three flavour 5-nucleotides were high at days 3 and 6. © 1999 Society of Chemical Industry     

Flavour components and antioxidant properties of several cultivated mushrooms

Three mushrooms, Clitocybe maxima, Pleurotus ferulae and Pleurotus ostreatus grey strain were used to study their flavour components and antioxidant properties. The volatile flavour components found comprised of six eight-membered carbon compounds and two aromatic compounds. The content total of soluble sugars and polyols was 125–270 mg/g. The content of monosodium glutamate-like components was 1.76–8.89 mg/g. The contents of flavour 5′-nucleotides ranged from 1.89 to 7.59 mg/g. Based on the results obtained, three mushrooms possessed highly intense umami taste. Ethanolic extracts were more effective in the inhibition of conjugated diene and scavenging ability on 1,1-diphenyl-2-picrylhydrazyl radicals, whereas hot water extracts were more effective in the scavenging ability of hydroxyl radicals. EC₅₀ values were less than 14 and 30 mg/ml for ethanolic and hot water extracts, respectively, indicating that the three mushrooms were relatively effective as they exhibited antioxidant properties, despite having scavenging abilities for hydroxyl radicals. Phenols were the major antioxidant components and the total contents were 5.10–11.1 mg gallic acid equivalents/g.     

Non-Volatile Taste Components of Different Cultivated Mushrooms at Mycelia,Primordium, and Fruit Body Cultivation Stages

Free amino acid, flavor 5’-nucleotides, organic acid, and the values of equivalent umami concentration of cultivable mushrooms, namely Pleurotus eryngii, Agrocybe aegerita, and Lentinus edodes, were investigated at different cultivation stages, mycelia, primordium, and fruit bodies. Fruit bodies were higher than mycelia in contents of total free amino acid, flavor 5’-nucleotides, and the values of equivalent umami concentration in three cultivated mushrooms, but lower in contents of total organic acid in P. eryngii and L. edodes, respectively. Contents of total organic acid at three cultivation stages of three cultivated mushrooms ranged from 32.65 to 125.50 mg g^–1 with the primordium stage of L. edodes being the highest. Overall, the amount of the nutrition and flavor components of mushroom might be related with mushroom species, fermentation way, and cultivated time. Some compounds could be also extracted from mycelia or primordium of mushrooms other than fruit body.     

Contents of amino acids,organic acids and 5′-nucleotides in Tricholoma giganteum

Tricholoma giganteum fruiting-bodies ere collected in a grassy place in Amami Oshima (Kagoshima Pref.) in October 1988 and the quantitative difference of 5′-nucleotides, free amino acids and organic acids, hich are responsible for the taste of dried mushrooms ere investigated. The amount of 5′-CMP, 5′-AMP, 5′-UMP and 5′-GMP ere 1250, 637, 863 and 566 mg kg^?1 respectively. 5′-GMP amounted to 17.1% of the total 5′-nucleotides. In the amino and organic acids, alanine, glutamic acid, serine, aspartic acid, succinic acid, oxalic acid and acetic acid ere present in the largest amounts.     

Non-volatile flavour components of Ganoderma tsugae

Ganoderma tsugae Murrill are currently popular and used in the formulation of nutraceuticals and as functional foods. The non-volatile components in the form of mature and baby fruit bodies (Ling chih), mycelia and fermentation filtrate from submerged culture were studied. Mycelia and filtrate contained significantly higher moisture contents (10.3% and 19.8%) and higher contents of carbohydrates, reducing sugars, crude ash and crude protein. Four forms of G. tsugae contained from 7.65% to 10.1% dry weight of total soluble sugars and polyols. Total free amino acid contents ranged from 2.50 to 149 mg g⁻¹ dry weight and in the descending order of filtrate, mycelia, baby Ling chih and Ling chih. Contents of monosodium glutamate-like components ranged from 0.16 to 26.0 mg g⁻¹ whereas, contents of sweet components ranged from 0.50 to 24.6 mg g⁻¹. The bitter components were predominant. Contents of total and flavour 5^′-nucleotides were high in filtrate (5.48 and 3.10 mg g⁻¹, respectively). The umami intensities were expected to be in the descending order of filtrate, mycelia, baby Ling chih and Ling chih.     

Composition and non-volatile taste components of Hypsizigus marmoreus

Two strains of Hypsizigus marmoreus (Peck.) Bigelow (Tricholomataceae) are successfully cultivated and commercially available in Taiwan, and their composition and non-volatile taste components of fruit bodies and mycelia were studied. Both fruit bodies were higher than mycelia in contents of carbohydrate, ash and fiber but lower in contents of fat and protein. Total sugar and polyol contents were 45.47-91.50 mg/g and total free amino acid contents were in the descending order of white strain fruit bodies (122.97) > normal strain fruit bodies (95.94) > white strain mycelia (53.20) > normal strain mycelia (46.87 mg/g). Monosodium glutamate-like components of both fruit bodies were 3-4-fold higher than those of both mycelia. Total 5′-nucleotides contents were 6.43-11.02 mg/g with white strain fruit bodies being the highest. Equivalent umami concentrations of both fruit bodies were higher than those of mycelia. Overall, H. marmoreus fruit bodies possessed highly intense umami taste.     

Comparison of free amino acids and 5′-nucleotides between Tuber fermentation mycelia and natural fruiting bodies

The profiles of free amino acids and 5′-nucleotides were first compared between Tuber fermentation mycelia and natural fruiting bodies. A total of 20 free amino acids and five 5′-nucleotides were identified in the Tuber fermentation mycelia and natural fruiting bodies. Not only the total contents of the free amino acids and 5′-nucleotides, but also the contents of umami amino acids and flavour 5′-nucleotides in the fermentation mycelia were higher than those in the fruiting bodies. By the addition of soybean flour in the fermentation media, the flavour 5′-nucleotides content in the fermentation mycelia was significantly increased, and the equivalent umami concentration of the fermentation mycelia (i.e., 608.07 g/100 g) was approximately 38.1-93.4 times higher than those of the fruiting bodies. From the viewpoint of umami taste, this work confirms the potentiality of Tuber fermentation mycelia as the alternative resource for its fruiting bodies.     

Physicochemical and flavour characteristics of Maillard reaction products derived from Aloididae aloidi muscle enzymatic hydrolysates coupled with High-Pressure Processing

Maillard reaction (MR) plays a crucial role in food processing and storage, and Maillard reaction products (MRPs) contribute to improve flavour of foods. In this study, Aloididae aloidi enzymatic hydrolysates lyophilised powder coupled with high-pressure processing (F₁) and atmospheric pressure (F₂) was used to evaluate physicochemical and flavour properties after MR. Compared with F₂, F₁ has not only higher organic acid, 5′-nucleotides and free amino acid (FAA) content, but also a reduced proportion of bitter amino acids. After MR, significant changes in MRPs were found, such as the accumulation of intermediate and browning products, the decline of pH. Furthermore, the content of FAAs and 5′-nucleotides in MRPs showed an obvious decrease, whereas the total content of organic acid increased. In addition, the electronic nose (e-nose) and gas chromatography-mass spectrometer (GC-MS) results showed that the content of volatile compounds with meaty flavour increased in MRPs and aldehydes with fishy flavour obviously decreased. To sum up, the enzymatic hydrolysis coupled with high-pressure processing and MR can better improve the flavour.     

Non-volatile taste components of various broth cubes

Commercial soup bases, in the form of broth cubes available in the market, include chicken, mushroom, pork and seafood broth cubes. The non-volatile taste components of four broth cubes were studied. Equivalent umami concentration (EUC) values of these broth cubes were evaluated and compared with their sensory results from hedonic tests. Only two soluble sugars, lactose and sucrose, were found. Contents of total free amino acids and monosodium glutamate (MSG)-like components ranged from 0.51 to 1.04 mg g⁻¹ and 0.48 to 0.56 mg g⁻¹, respectively. Contents of 5′-nucleotides and flavour 5′-nucleotides ranged from 2.67 to 3.66 mg g⁻¹ and 2.58 to 3.33 mg g⁻¹, respectively. EUC values were low and the umami intensities of one gramme of four soup bases were equivalent to those given by 0.14–0.32 g MSG. Mushroom and pork soups were more preferred, whereas seafood soup was less preferred. Correlations of EUC values with sensory scores were established for chicken, pork and seafood soups.     

Chemical composition and non-volatile components of Croatian wild edible mushrooms

The chemical composition (dry matter, crude protein, crude fat, total carbohydrates, and ash) and non-volatile components content (soluble sugars, free amino acids, and 5′-nucleotides) of 10 popular Croatian wild edible mushroom species (Agaricus campestris, Boletus edulis, Calocybe gambosa, Cantharellus cibarius, Craterellus cornucopioides, Entoloma clypeatum, Flammulina velutipes, Macroleptiota procera, Morchella elata, and Pleurotus ostreatus) were determined. All investigated mushrooms were found to be good sources of proteins and total carbohydrates, with contents varying in the ranges of 27.95–38.89, and 42.62–66.78 g/100 g, respectively. In addition, the fat contents were very low 1.34–6.45 g/100 g. B. edulis (19.87 mg/g) showed the highest concentration of essential amino acids and M. elata (14.25 mg/g) the lowest concentration. Monosodium glutamate-like components and total flavour 5′-nucleotides were the highest in C. cornucopioides (45.85 and 13.88 mg/g, respectively), and lowest in F. velutipes (7.63 and 1.05 mg/g, respectively). Equivalent umami concentration values in 10 Croatian wild edible mushrooms ranged from 73.78 to 1186.45 g MSG/100 g dry weight, and overall, all these mushrooms possessed highly umami taste.     

Nonvolatile taste components,nutritional values,bioactive compounds and antioxidant activities of three wild Chanterelle mushrooms

The chemical compositions, nonvolatile taste components and nutritional compounds of three wild edible Chanterelle mushrooms (C. cibarius Fr (CcF), C. cinnabarinus schwein (CcS) and C. tubaeformis Fr (CtF)) were evaluated. Results showed Chanterelle mushrooms were good sources of proteins and carbohydrates with low energy. CcS was rich in trehalose in free sugars and glucose in soluble sugars. Monosodium glutamate‐like free amino acids and flavour 5′‐nucleotides indicated Chanterelle mushrooms had good taste. Based on their amino acids compositions and nutrition evaluations, CcF, CcS and CtF were significant sources of amino acids and protein. CtF showed better protein quality than CcF and CcS. Stearic and oleic acids showed high contents in three mushrooms, and higher unsaturated fatty acids were found in CcF. Three mushrooms had high contents of K, Ca and Mg, and low content of Na. Organic acid and phenolic acids of three mushrooms were identified, and antioxidant activities were evaluated.     

Effect of lactic acid fermentation on antioxidant properties and phenolic acid contents of oyster (<Emphasis Type="Italic">Pleurotus ostreatus</Emphasis>) and chanterelle (<Emphasis Type="Italic">Cantharellus cibarius</Emphasis>) mushrooms

Fruiting bodies of Pleurotus ostreatus (oyster) and Cantharellus cibarius (chanterelle) mushrooms underwent acid fermentation using 3 strains of lactic acid bacteria (LAB) as starter cultures. Polyphenol contents, antioxidant activities, and phenolic acid contents in fresh, blanched, and fermented mushrooms were investigated. Fruiting bodies of oyster mushrooms exhibited higher total phenolic contents than chanterelle mushrooms. Blanching caused a decrease in polyphenol contents and antioxidant activities in both mushroom types. No important differences were observed in total phenolic compound contents (measured using Folin-Ciocalteau reagent) in mushrooms using different LAB strains. Lactobacillus plantarum was the most useful microorganism for lactic acid fermentation of fruiting bodies for reduction of the pH value. The highest concentrations of single phenolic acids: gallic, homogentisic, and ferulic acids were present in mushrooms fermented using L. plantarum.     

Nutritional contents of three edible oyster mushrooms grown on two substrates at Haramaya,Ethiopia, and sensory properties of boiled mushroom and mushroom sauce

The effects of wheat and bean straw growing substrates on nutrient contents of three edible oyster mushrooms and sensory properties of two mushroom foods were investigated. Moisture (fresh weight basis), crude protein, fat, fibre, ash, total carbohydrate, Fe, P and Zn (db) were ranged: 85.18–88.86%, 30.04–37.63%, 1.61–2.55%, 9.33–13.29%, 6.83–9.38%, 29.68–32.53%, 4.86–5.66 mg per 100 g, 12.39–15.36 g kg^?1 and 54.61–65.98 mg kg^?1, respectively. Moisture, fat and fibre were significantly (P < 0.01) affected by substrates, species and their interactions. Substrates showed no differences on ash, Fe and P (P > 0.05). Protein content was high for mushrooms grown on bean straw. Pleurotus sajor‐caju grown on bean straw had high protein, ash, Fe and P contents. No significant (P > 0.05) sensory acceptability differences were observed for boiled mushroom and mushroom sauce except colour of boiled mushrooms. In Ethiopia, if mushroom consumption is popularised, the support for food nutrition security is substantial.     

Edible mushrooms: a potential source of essential amino acids,glucans and minerals

The main chemical and biochemical constituents of nine edible mushrooms were evaluated in this study. An enzymatic method was used to determine the α‐ and β‐glucan contents, and the amino acid (AA) profiles were evaluated by RP‐HPLC‐DAD. The recommended dietary allowance (RDA) of the nutrients was evaluated. Finally, principal component analysis (PCA) was used to group the mushrooms according to their AA, glucans and chemical composition. All mushrooms evaluated can be considered as a potential and alternative source of dietary fibre (24.4–46.62%) and protein (16.47–36.96%) in a diet, with low contents of fat (1.40–2.08%). Phosphorus, potassium, iron, copper and zinc were the main minerals found in the mushrooms, whereas sodium concentration was negligible. All essential AA were detected in the mushrooms, with Pleurotus ostreatus (black oyster) representing the main source of essential amino acids among the samples. The contents of β‐glucan ranged from 1.58 to 16.91 mg g^?1 of dry matter among the mushrooms and Pleurotus eryngii presented the highest amount of this component. Pleurotus ostreatus (black oyster) and P. eryngii were also grouped together due to similarities in their phosphorous and arginine contents. Among the main results, it can highlight the high concentration of dietary fibre and essential amino acids of the edible mushrooms.     

Nonvolatile taste components of solid-state fermented adlay and rice by Phellinus linteus

Phellinus linteus (Berkeley & Curtis) Teng (Hymenochaetaceae) was inoculated into cooked grains, and new products were formed after fungal fermentation and their nonvolatile taste components were studied. Contents of ash, fat, fiber, and protein in inoculated products [Phellinus-fermented adlay (PFA) and rice (PFR)] were much higher than those in uninoculated controls [polished adlay (PA) and rice (PR)]. Contents of total soluble sugars and polyols were in the descending order: PFA > PFR > PA > PR. Contents of total free amino acids and total and flavor 5′-nucleotides in PFA and PFR were much higher than those in PA and PR. Equivalent umami concentrations in PFA and PFR (917.17 and 222.96 g monosodium glutamate (MSG)/100 g, respectively) were higher than those in PA and PR (4.88 and 0.32 g MSG/100 g, respectively). Evidently, Phellinus-fermented products possessed high level of umami taste.