Physicochemical and nutritional properties and volatile constituents of six Japanese plum (<Emphasis Type="Italic">Prunus salicina</Emphasis> Lindl.) cultivars

The aim of this study is to contribute to the qualitative characterisation of six cultivars of Japanese plum (Prunus salicina Lindl.), i.e. ‘Black Amber’, ‘Suplumeleven’, ‘Fortune’, ‘Larry Ann’, ‘Suplumsix’ and ‘Songold’, by investigating their physicochemical and nutritional properties and their volatile fractions. The results indicate that the plum has a mean sugar content of 15% (between 12.3 and 17.8%), dietary fibre 1.2% (from 0.84 to 1.50%) and a mean energy value of 255 kJ 100 g⁻¹ of fresh produce (from 183 to 331 kJ 100 g⁻¹). ‘Black Amber’ has the highest phenolic and anthocyanin contents and the greatest total antioxidant activity. In terms of their volatile fraction, Japanese plums are relatively poor in volatile compounds in comparison with other stone fruits. However, there are significant differences between the cultivars studied, with ‘Fortune’ standing out as the richest in volatile compounds and especially in esters.     

不同加工方式对紫色马铃薯中酚类物质的影响

紫色马铃薯富含花青素、绿原酸等多酚类物质,是价格低廉、取材广泛的天然抗氧化剂来源。为探明加工方式对紫色马铃薯中酚类物质的影响,最大程度地保留抗氧化活性物质,以3个紫色马铃薯品系和白色马铃薯品种‘夏波蒂’为实验材料,采用蒸制、微波和水煮3种加工方式进行处理,分析加工前后紫色马铃薯块茎中花青素、绿原酸、自由态多酚、结合态多酚的含量及抗氧化活性的变化。结果表明,3种加工方式均导致紫色马铃薯花青素含量的降低;与对照品种‘夏波蒂’相比,蒸制和微波处理后紫色品系马铃薯自由态多酚、结合态多酚、绿原酸的含量及抗氧化活性均更高,而水煮处理后,除结合态多酚的含量增加外,其余成分的含量均显著降低。因此,微波和蒸制加工可以更好地保留紫色马铃薯中的多酚类物质,从而发挥其抗氧化作用。     

Physicochemical characteristics and antioxidant activities of grape Yakju

The physicochemical characteristics and antioxidant activities of grape yakju, a traditional Korean alcoholic beverage, were investigated during the fermentation process. Reducing sugars decreased while total acid content increased throughout fermentation. Alcohol content increased up to 16–20% after the 10^th day of fermentation. The content of total phenolic compounds and flavonoid in yakju increased with fermentation time. Anthocyanin was found only in yakju made from grapes. ‘Muscat Baily A (MBA)’ yakju was the most preferred regarding color, flavor, taste, and overall acceptance. Antioxidant activities of grape yakju, except for the 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging activity, increased with fermentation time, with the following in the order of increasing antioxidant activity after fermentation: ‘MBA’, ‘Campbell’, ‘Kyoho’, and control yakju. Antioxidant activities of grape yakju depended on total flavonoid content rather than total phenolic compounds.     

Anthocyanins, flavonols and hydroxycinnamates: an attempt to use them to discriminate Vitis vinifera L. cv ‘Barbera’ clones

Anthocyanin and flavonol profiles of Vitis vinifera berry skin have been diffusely studied in past years to identify the effects exerted by climate, environment and cultural practices on their biosynthesis. They have also been used for chemotaxonomic purposes with the aim of classifying grape varieties. Hydroxycinnamates and phenolic acids are the most important group of non-flavonoid phenols in grapes and wines. In the present work six ‘Barbera’ clones were grown in the same site to evaluate the influence of two seasons on the accumulation of flavonoids and hydroxycinnamates at maturity. Berry skins were extracted in an ethanolic buffer and flavonoids and hydroxycinnamates were separated by HPLC. Two principal component analysis (PCA) models were built to identify phenolic parameters exploitable to classify clones. The PCA scores were taken further to perform discriminant analysis to evaluate the degree of classification possible. A significant seasonal variability was observed for most phenolic features, whereas some parameters such as total anthocyanin expressed on a per berry basis, the sum of tri-hydroxylated anthocyanin percentages, the percentages of kaempferol glucuronide and the total hydroxycinnamate content were stable over the seasons. The percentage of individual anthocyanin alone, not associated with maturity data, was not effective in classifying clones; in association with maturity data it allowed to discriminate clones, similarly to what it was previously assessed for classifying varieties. The results indicated that LDA models developed on the PCA scores including maturity data correctly classified 75% of clones.     

Some quality characteristics and nutritional properties of traditional egg pasta (erişte)

In the present study, erişte, a typical egg pasta of Turkey, was investigated according to its quality characteristics and nutritional properties and compared with the industrially produced ones. Cooking properties of traditional erişte were generally lower than those of produced in pasta companies, on the other hand total dietary fiber (TDF) and resistant starch (RS) contents were higher. TDF and RS contents of samples were in the range of 3.6–6.3 and 0.56–1.21%, respectively. A correlation (r=0.458) was found between RS and TDF contents indicating that production technique of traditional erişte results in formation of RS. The results also showed that all erişte samples can be regarded as at least ‘good’ sources of dietary fiber according to Food and Drug Administration (FDA) requirements. Average protein digestibility values of traditional erişte and industrially produced erişte were found to be 89.1 and 95.7%, respectively.     

Impact of minimal heat-processing on pectin methylesterase and peroxidase activity in freshly squeezed <Emphasis Type="Italic">Citrus</Emphasis> juices

The impact of minimal heat-processing of juices on the activities of endogenous pectin methylesterase (PE) and peroxidase (POD) was compared between Citrus species. Mono-cultivar juices were produced from three orange (Citrus sinensis (L.) Osbeck cvs. ‘Navelina’, ‘Salustiana’, and ‘Navelate’), two lemon (Citrus limon (L.) Burm. f. cvs. ‘Verna’ and ‘Primofiori’), and two Clementine mandarin varieties (Citrus reticulata Blanco cvs. ‘Marisol’ and ‘Clemenules’). Two mandarin hybrids (cvs. ‘Ortanique’ and ‘Clemenvilla’) were likewise used. The freshly squeezed juices were subjected to continuous treatments at six different temperatures (42–92 °C) with subsequent re-cooling on the pilot plant scale. In fresh Citrus juice, POD activities notably varied between 0.2 and 7.5 nkat g⁻¹ of juice, whereas PE activities were more uniform (0.4–1.5 PE units g⁻¹). In all juices, except ‘Ortanique’ juice, heating ≥42 °C for 12 s reduced POD activity below 4.3% of the maximum activity in fresh Citrus juice. Thermal tolerance of the thermo-labile PE fraction was overall much higher, but varied among juices during heating at temperatures ≤62 °C. Overall thermal resistance of PE was though comparable, with deactivation exceeding 84%, mostly even 90%, after thermal treatments ≥72 °C. Unlike POD, total PE activity proved to be an indicator of freshness that is universally applicable to Citrus juices derived from orange, mandarin, and lemon or blends thereof. Freshly squeezed juices can analytically be distinguished from cold-stored, minimally processed products that display an almost completely inactivated thermo-labile PE fraction and thus extended shelf life.     

Identification and quantification of anthocyanins from the grains of black rice (Oryza sativa L.) varieties

The purpose of this research was conducted to determine anthocyanin content from the grains of 10 Korean black rice varieties. Moreover, the primary constituents including protein and oil were evaluated. Anthocyanins, cyanidin-3-O-glucoside (1) and peonidin-3-O-glucoside (2), were isolated and elucidated using reversephase C₁₈ chromatography, nuclear magnetic resonance (NMR) spectroscopy, and high performance liquid chromatography (HPLC) with diode array detection and electrospray ionization/mass spectrometry (DAD-ESI/MS). Anthocyanin showed significant differences and cyanidin-3-O-glucoside (1) (52.1±6.3-1,601.0±8.5 μg/g) exhibited a markedly higher content than peonidin-3-O-glucoside (2) (ND-82.6±1.2 μg/g). Among varieties, ‘Heugjinjubyeo’ showed the highest anthocyanin (1: 1,601.0±8.5, 2: 82.6±1.2 μg/g), whereas ‘Heughyang’ was the lowest (1: 52.1±6.3 μg/g, 2: ND). Protein and oil exhibited the minor differences and their contents ranged from 10.7±0.0 to 14.1±0.1% and from 2.1±0.0 to 2.9±0.0%. Overall results suggest that anthocyanin can be a key factor in functional property of black rice and ‘Heugjinjubyeo’ may be very important source concerning nutritional value.     

Antioxidant potentials of skin,pulp, and seed fractions of commercially important tomato cultivars

The rationale of this study is to compare the levels of different antioxidants present in commercially important tomato cultivars of India, specifically developed to grow in high altitude and plain regions. Major antioxidant components like lycopene, ascorbic acid, phenolics, and quenching capacity of free radicals were analysed in different fractions of tomato fruit, i.e., skin, pulp, and seed fractions. Significant differences in antioxidant components were observed among the fractions of the different cultivars studied. Lycopene content was found to be more in high altitude cultivars (‘Sindhu’ and ‘Shalimar’); however, ascorbic acid and phenolic content were found to be higher in plain region cultivars (‘PKM1’ and ‘CO3’). To evaluate the antioxidant capacity, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) assays were performed. High altitude cultivars showed 10–15% higher DPPH free radical scavenging activity and 20–30% increase in FRAP than the plain region cultivars. Among the different fruit fractions analysed, skin showed the highest level of antioxidants levels and free radical scavenging activities in all the cultivars tested. The difference in the antioxidants level and activity may be attributed to the genetic variability of the cultivars.     

Evaluation of nutritional and physico-mechanical characteristics of dietary fiber-enriched sweet potato pasta

The objective of the present study was to enhance the utilization of sweet potato (Ipomoea batatas Lam.) as a slowly digestible food by developing dietary fiber-fortified pasta from it. Swelling index as well as cooking loss (%) was more for the pasta made from the pale cream-fleshed variety, Sree Arun (V1) than that from the orange-fleshed variety, Sree Kanaka (V2), and least values were obtained in the pasta fortified with rice bran. Fortification with oat bran, wheat bran, and rice bran elevated the crude protein content to 5–10% in the pasta. Total and insoluble dietary fiber fractions were more in the pasta from Sree Arun (6–17 and 5–14%, respectively) than those from Sree Kanaka (5.25–15 and 3.7–11%, respectively) with the highest values in the wheat bran-fortified pastas. All the fiber-fortified pastas (10 and 20% level of fortification) had slow and progressive starch digestibility over 2 h compared to the control pastas. While approximately 70% of the total starch was rapidly digestible for the control pastas from both the varieties, this was drastically reduced to 45–54% in the test pasta from V1 and 37–50% in V2. Accordingly, the retention of resistant starch (RS; undigested starch after 2 h) in the control pastas was only 14–17%, while it was 38–49% in the test pastas from V1 and 39–55% from V2, with higher RS in the 20% fortified pastas. Texture profile analysis showed that the firmness (N) and toughness (Ns) increased with increase in the fortification level of fiber sources. The progressive starch digestibility coupled with high-resistant starch after 2 h indicated the potential of fiber-fortified sweet potato pasta as an ideal food for the diabetic and obese people.     

Antioxidant and antiproliferative activities of grape seeds from different cultivars

Grape seeds contain high levels of phytochemicals, which have been correlated with a decreased risk of chronic diseases. In this study, grape seeds from 10 different cultivars (‘SV 18315’, ‘Naples’, ‘Agawam’, ‘Aligote’, ‘V.50151’, ‘Cabernet Sauvignon’, ‘Urbana’, ‘Baco22A’, ‘Clinton’, and ‘Campbell Early’) were evaluated for their antioxidant and antiproliferative activities. The antioxidant activity of the grape seeds was evaluated by radical scavenging activities and reducing power. The antiproliferative activity was assessed by the inhibition of MCF7, NCI-H460, HCT116, and MKN45 cancer cell proliferation. The total polyphenol and flavonoid contents were determined by spectrophotometric methods. ‘Cabernet Sauvignon’ and ‘Baco22A’ had high polyphenol (4,369.2 and 3,747.0 mg/100 g seeds) and flavonoid contents (3,072.7 and 2,032.9 mg/100 g seeds). ‘Cabernet Sauvignon’ and ‘Baco22A’ also possessed the highest radical scavenging activity. In addition, these were showed generally higher antiproliferative activity than other cultivars. Both the polyphenol and flavonoid contents were positively correlated with radical scavenging activity (R²>0.9). These results may provide basic information about health-beneficial effects of grape seeds.     

Antioxidant Capacity and Antioxidant Content in Roots of 4 Sweetpotato Varieties

Abstract: The antioxidant contents (β-carotene, chlorogenic acid, and vitamin C) as well as the antioxidant capacity (ORAC, FRAP, and ABTS) of 4 sweetpotato varieties were measured in this study. The sweetpotato varieties were cultivated under different water regimes and also subjected to thermal processing. The results show that the 2 orange-fleshed varieties (Resisto and W-119) contain significant more β-carotene, chlorogenic acid, and vitamin C than the 2 cream-fleshed varieties (Bosbok and Ndou). Thermal processing decreased the carotenoid and vitamin C content of all the varieties but increased the chlorogenic acid content and antioxidant capacity. Drought stress appears to increase the β-carotene, vitamin C, and chlorogenic acid contents as well as the antioxidant capacity of some of the sweetpotato varieties, especially W-119.     

Properties and qualities of rice flours and gluten-free cupcakes made with higher-yield rice varieties in Korea

Korean rice varieties, ‘Druryechanbyeo’ and ‘Boramchanbyeo’, were developed to get higher yields and to be used in rice products. The rice grains were dried and milled into rice flours after first going through the soaking process. The properties and qualities of cupcakes made with dry-milled rice flours were compared with cupcakes made with commercial dry-milled rice flours (CDRF). The newly developed rice flours (NDRF) had higher apparent amylose content, water binding capacity, swelling power, and peak viscosities, but had lower damaged-starch content, gelatinization temperature, and final and setback viscosities than CDRF. The specific gravity of batter, and hardness and springiness of cupcakes were lower in NDRF than in CDRF. The cake textures from ‘Boramchan’ NDRF were more preferable than those from ‘Druyechan’ NDRF. The specific volume and overall quality of cupcake were correlated positively with amylose content and water binding capacity, but negatively with damaged starch of rice flours.     

Quality and safety of a new rapeseed ‘Kangyu’ cultivated at different regions in Korea

The quality and safety of rapeseed are greatly affected by glucosinolate and erucic acid. To determine the quality of a new variety, ‘Kangyu’ was cultivated at 3 different regions and analyzed to evaluate oil quality and glucosinolates contents. The new cultivar accumulated 38–43%(w/w) of oil and 5–14 μmol/g of glucosinolates, whereas the local race contained 43% and 52 μmol/g, respectively. The total glucosinolates in ‘Sunmang’ was above the permissible limit. All ‘Kangyu’ samples had safe fatty acid compositions but the local race contained 43% of erucic acid (C22:1) that is far from the International Standard. The contents of oleic (C18:1), linoleic (C18:2), and linolenic acid (C18:3) in ‘Kangyu’ were 61–65, 21–23, and 9–10%, respectively. Consequently, ‘Kangyu’ was good oil source in Korea in terms of erucic acid (C22:1) and total glucosinolates for human health.     

Anthocyanin content, antioxidant activity, and selected physical properties of flowable purple-fleshed sweetpotato purees

ABSTRACT:  With high levels of polyphenolic compounds, purple-fleshed sweetpotatoes (PFSP) have been utilized as a healthy food commodity and source of natural food colorants in Asia. In the U.S. sweetpotato industry, there are growing interests in exploring these market opportunities for PFSP. A locally grown PFSP cultivar was analyzed for antioxidant properties. The total phenolic content ranged from 313.6 to 1483.7 mg chlorogenic acid equivalent/100 g fresh weight (fw), and anthocyanin contents were between 51.5 and 174.7 mg anthocyanins/100 g fw. The DPPH radical scavenging activities and were 47.0 to 87.4 μmol trolox equivalent (TE)/g fw, and the oxygen radical absorbance capacity (ORAC) values were between 26.4 and 78.2 μmol TE/g fw. Unlike orange-fleshed sweetpotatoes (OFSP), the steamed roots of PFSP formed a thick paste, which required a process modification to produce flowable purees. Rheological testing indicated that adjusting the dry matter of PFSP to 18%-21% produced purees with flow properties similar to the OFSP purees. The PFSP purees had polyphenolic content and antioxidant capacity within ranges reported for various purple-colored fruits and vegetables.     

Study of phenolic composition and sensory properties of red grape varieties in danger of extinction from the Spanish region of Castilla-La Mancha

This paper reports on a study of the profiles of different phenolic compounds (anthocyanins, flavonols, hydroxycinnamic acids and stilbenes) of five minor red grape varieties from the Spanish region of Castilla-La Mancha (Bobal, Moravia Agria, Moravia Dulce, Rojal and Tortosí) and a traditional variety from this growing region (Cencibel) as reference. Grape skin extracts of each variety were analysed by High Performance Liquid Chromatography coupled to Diode Array Detector (HPLC–DAD). The content of grape skins in anthocyanins (21.1–453 mg kg⁻¹), flavonols (26.9–288 mg kg⁻¹) and hydroxycinnamic acids (6.80–18.2 mg kg⁻¹) showed differences according to mainly varietal origin, although other important factors have to be taken into account such as the degree of ripeness, berry size or vintage year. In all the studied varieties, the major anthocyanin was malvidin 3-glucoside (>40%) with the exception of Rojal variety, which major one was peonidin 3-glucoside together with cyanidin 3-glucoside. Moravia Dulce and Rojal varieties contained more than 46% of quercetin 3-glucuronide; the rest of them contained less than 27%. No relation was found between profiles of hydroxycinnamic acids in the studied samples and their variety or year of vintage. All the studied grapes presented high concentrations of stilbenes that could be interesting due to the health benefits.     

Quality characteristics of different red pepper cultivars (<Emphasis Type="Italic">Capsicum annuum</Emphasis> L.) for hot paprika production

Twelve hybrids obtained by crossing of different Hungarian cultivars and the Spanish ‘Jaranda’, ‘Jariza’ and ‘Jeromín’ have been studied. The aim of this work was to select those peppers with high capsaicinoids content, and good agronomic and industrial characteristics, as ‘Jeromín’, the only local cultivar used for pungent (hot) paprika, has a low and irregular pungency depending on the year. The crop productive characteristics, ASTA colour, carotenoid pigment content and pungency of the paprika has been studied and elaborated following the traditional procedure of La Vera (Extremadura, Spain). The productive characteristics and pigment concentration of the crossings were, in general, similar to that of local cultivars, and all of them could be suitable for hot paprika production, because their capsaicinoid content was higher than that of ‘Jeromín’ (78 mg kg⁻¹ dwt of total capsaicinoids). The most pungent hybrids were Kibedicsipos × Jariza, Jeromín × Szegedi178 and Jaranda × Szegedi179, with a total capsaicinoid content of 1,240, 1,107, and 997 mg kg⁻¹ dwt, respectively. Their paprikas showed a carotenoid pigment content higher than that of ‘Jaranda’, which is considered as a high quality paprika.     

Compositional characterisation of some apple varieties

 Ten apple varieties, harvested at commercial maturity, were analysed, paying special attention to the level of phenolic compounds and polyphenol oxidase (PPO) activity. The results pointed to great quantitative differences in the composition of the apple varieties, and particularly in their phenolic contents. Their total polyphenol content ranged from 2.3 to 3.6 g/kg. Chlorogenic acid was the main phenolic compound found in the varieties studied, and its concentrations varied from 30 to 430 mg/kg, and were 4–20 times higher than those of catechins. Only in Szampion and Elstar were the concentrations of catechins higher. Amongst the flavanol monomers, the main compound was (–)epicatechin, whose concentration varied from 18 to 89 mg/kg. The (+)catechin concentration ranged from 4 to 21 mg/kg. The dominant proanthocyanidins were oligomers up to trimers. In Warta apples, the concentrations of these oligomers were about 3 times higher than those of monomers. The level of PPO activity ranged from 270 units (U)/g in Szampion to 3120 U/g in Warta. No correlation was found between the concentrations of certain phenolic compounds, nor between PPO activity and phenolic or ascorbic acid concentrations. The results gave important information regarding the best use of the apple varieties investigated, i.e. for direct consumption due to their high nutritional value, or for processing. Received: 7 May 1999     

A correlation between the level of phenolic compounds and the antioxidant capacity in cooked-with-rice and vegetable soybean (Glycine max L.) varieties

This study was undertaken to determine the content of phenolic compounds contained in embryo, cotyledon and seed coat of nine soybean (Glycine max L.) varieties. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity was also measured to determine the correlation between the level of phenolic compounds and antioxidant capacity. A total of 10 anthocyanin constituents and 21 phenolic compounds was detected and quantified. In all nine varieties, the seed coat and cotyledon had the highest and lowest levels of phenolic compounds and anthocyanins, respectively despite the fact that all of them showed a wide variation in total amounts of phenolic compounds and anthocyanins in seed coat, embryo, and cotyledon. The seed coat tissue, but not other seed parts, showed a strong correlation between the seed coat color and the content of both phenolic compounds and anthocyanins. The brown and black soybean seed coat contained much higher levels of phenolic compounds and anthocyanins in seed coat tissue than the yellow or green coat soybean. Among the individual phenolic compounds, syringic acid (214 μg g⁻¹) and chlorogenic acid (31 μg g⁻¹) were highest in seed coat and embryo, respectively. Myricetin was highest both in whole seed (16.7 μg g⁻¹) and cotyledon (16.0 μg g⁻¹), being equivalent to 20 and 30% of total phenolic compounds, respectively. Among the 10 anthocyanins, cyanidin-3-glucoside was found to accumulate at the highest level in the seed coat (1783 μg g⁻¹), whole seed (106 μg g⁻¹) and embryo (0.35 μg g⁻¹), which correspond to 95, 96, and 40% of the total anthocyanin contents, respectively. The cotyledon accumulated pelargonidin-3-glucoside (0.39 μg g⁻¹) at the highest level that is equivalent to 62% of total anthocyanin contents. DPPH activity was found to have a strong correlation (^***probability < 0.001) with phenolic compounds (0.67^***) and anthocyanins (0.70^***).J. A. Kim, W. S. Jung, and S. C. Chun are equally contributed to this work.