Effects of organic and conventional production systems on quality and nutritional parameters of processing tomatoes

BACKGROUND: The impact of organic and conventional production systems on quality and nutritional parameters of fruits and vegetables is still under discussion. The objective of this study is to determine whether the production system has a significant effect on the quality and nutritional content of one variety of processing tomatoes grown on a commercial scale by comparing three different growers for two production years. RESULTS: Conventional tomatoes appeared to be more mature at time of harvest as determined by visual inspection of color. Total and soluble solids were significantly higher and consistency was greater in organic tomatoes. Differences in nutrient content were not statistically significant between production systems. Glutamate, glutamine, and tyrosine levels were significantly higher in conventional tomatoes, as were total nitrogen and ammonium concentrations. CONCLUSION: Results from this study show that nutritional and quality parameters vary greatly by grower, production system, and year for the same tomato cultivar. Significantly higher average soluble solids content and consistency in organic tomatoes are especially important to the processing tomato industry. The apparent slower development of organic tomatoes may be responsible for many of the significant findings in this study and may explain some of the conflicting reports in previous literature. Copyright © 2008 Society of Chemical Industry     

Nitrogen fertilisation in coriander (Coriandrum sativum L.): a review and meta‐analysis

Nitrogen (N) fertilisation is one of the most important external inputs in assessing coriander seed yield and plant growth. Recent concerns related to the misuse of N fertilisers in agricultural environments, however, stress the opportunity for a fine‐tuning of N management in order to optimise the use of this element, avoiding losses and reducing environmental hazards. In this study, some results from the literature concerning N fertilisation in coriander are reviewed and, by means of statistical analysis, an attempt is made to derive from them some general suggestions about practices of N fertilisation. In most cases examined, N fertilisation allowed a 10–70% increase in seed yields in comparison with each respective untreated control. The efficiency of use of this element, however, has proven to be greatly dependent on the overall fertility conditions of the growing site. The greatest yield advantages were actually found in more favourable environments, whereas in low‐yielding environments plants reached their maximum yield with a comparatively reduced N supply. In low‐yielding environments a careful risk/benefit assessment of this practice is therefore advisable. No definite conclusion could be drawn at this stage about essential oil yield and composition in relation to N fertilisation. Copyright © 2009 Society of Chemical Industry     

Influence of Ca2+, K+ and NO3− fertilisation on nutritional quality of pepper

A study was conducted in order to assess the effect of different fertilisation levels of Ca²⁺, K⁺ and NO₃^? on the bioactive nutrient content in red pepper (Capsicum annuum L) fruits. The experiment was carried out in a greenhouse, under hydroponic culture. Lycopene, β‐carotene, vitamin C, total phenolic compound, sugar, nitrate and potassium contents and antioxidant activity were determined. Increasing Ca²⁺ and NO₃^? concentrations in the root medium increased the lycopene and β‐carotene contents in pepper. Antioxidant activity was determined in the hydrophilic (HAA) and lipophilic (LAA) fractions. HAA was increased by intermediate and high Ca²⁺ concentrations in the culture medium. However, LAA was raised only by NO₃^? treatments. Vitamin C, sugar and total phenolic acid contents were not affected by Ca²⁺ or NO₃^? treatments. K⁺ treatments had no effect on nutritional quality of pepper. An increased supply of Ca²⁺ and NO₃^? in the culture medium could constitute a useful practice for improving the nutritional attributes of pepper as well as its commercial quality. Copyright © 2004 Society of Chemical Industry     

Pepper antioxidant composition as affected by organic,low‐input and soilless cultivation

BACKGROUND: The aim of this work was to study the effects of organic (O), low‐input (LI) and soilless (SL) cultivation on pepper nutritional quality and antioxidant activity. For that, 24 commercial greenhouses were selected following strict criteria in order to reduce the influence of environmental conditions and realistically reflect commercial production systems. Fruits were harvested at two maturity stages (green and red) and three harvesting times during two consecutive years. RESULTS: Pepper antioxidant activity mainly stemmed from water‐soluble compounds, including organic acids and phenolic compounds. Only some differences in sugars and malic and citric acid concentrations were detected between the O and LI systems. Sugars, phenolic compounds, ascorbic acid and hydrophilic antioxidant activity were higher in the SL system. In spite of these differences, overall differences between harvesting times or between years were far greater than those due to the cropping system. CONCLUSION: The main differences in the nutritional quality of pepper fruits were observed between the soil (O and LI) and SL (the most favourable) systems. The results highlight the importance of comparing different harvesting times and years in order to study the effect of cropping system on a specific crop. Copyright © 2009 Society of Chemical Industry     

On fumonisin incidence in monoculture maize under no‐till,conventional tillage and two nitrogen fertilisation levels

BACKGROUND: Fusarium ear rot and fumonisin contamination are serious problems for maize growers. The lack of maize genotypes highly resistant to fumonisin contamination emphasises the need for management strategies to prevent contamination by this mycotoxin. There are conflicting reports regarding no‐till and nitrogen (N) fertilisation practices in relation to the incidence of fumonisins. In this study the effect of no‐till compared with conventional tillage and of N fertilisation rates on fumonisin occurrence was investigated over three years in Northern Italy. RESULTS: The average contamination of grain by fumonisins B₁ and B₂ over the three years was significantly different, with a lower value in 2000 (516 µg kg^?1) than in the other years (5846 and 3269 µg kg^?1 in 2001 and 2002 respectively). Conventional tillage and no‐till treatments had no significant effect on the incidence of fumonisins. This finding suggests that above‐ground residues infected by Fusarium would not lead to an increase in fumonisin incidence. However, N fertilisation significantly increased fumonisin levels, by 99 and 70% in 2000 and 2001 respectively. CONCLUSION: Maize monoculture does not show a cumulative effect on the occurrence of fumonisins, while high rates of N fertiliser consistently result in elevated fumonisin levels. Both these effects can be influenced by annual meteorological fluctuations. Copyright © 2008 Society of Chemical Industry     

Pepper mineral composition and sensory attributes as affected by agricultural management

BACKGROUND: Given the contradictory information available concerning the potential beneficial effects of organic production on food quality, there is a need for studies that determine the real effect of cropping systems on fruit quality. A two‐year farm study was therefore conducted to assess differences in the mineral composition and sensory quality of pepper (Capsicum annuum L. cv. Quito) fruits cultivated in organic (O), low‐input (LI) and soilless (SL) systems. Twenty‐four greenhouses were selected following strict criteria in order to reduce the influence of environmental conditions and accurately and realistically reflect commercial production systems. RESULTS: The soil (O and LI) systems provided higher Ca and Mg concentrations than the SL system. In addition, fruit colour was favourably evaluated in green and red peppers from both soil systems. In contrast, SL fruits showed higher firmness in the green stage (related to higher flesh thickness). All fruit parameters that were affected by the cropping system were also affected by the harvesting time. CONCLUSION: The main differences as regards the mineral composition and sensory attributes of the resulting fruit were observed between the soil (O and LI) and SL systems. The benefits of O peppers with respect to LI fruits could only be described as an absence of pesticide residues. Harvesting time can affect fruit composition and quality to a greater extent than cropping system. Copyright © 2009 Society of Chemical Industry     

Sustainable nitrogen fertilisation in sweet pepper: assessing growth and fruit quality and the potential nitrate pollution from different organic manures

BACKGROUND: The use of organic cultivation with manures does not avoid the risk of high nitrate concentrations if nutrient management is inefficient. So we studied the influence of three organic manures combined or not with additional chemical fertilisers on growth and yield of sweet pepper (Capsicum annuum L.), and on the soil and plant N concentrations. RESULTS: After 3 years of organic cultivation, poultry manure caused the highest soil pollution. The evolution of nitrate and organic matter in soil showed a pattern close to that of plant growth. The addition of mineral fertiliser increased vegetative growth and yield, and a cumulative season effect was observed. In treatments with no additional mineral fertiliser N translocation from leaves to fruits happened. A cumulative effect of seasons on fruit quality and a reduction near to 30% was observed in the first fruit quality category after 3 years. The fruit vitamin C content was reduced by increasing N fertilisation. CONCLUSION: The effects of organic fertiliser on soil and plant growth and yield depended on the type of manure used, its rate, and consecutive crop seasons. Horse manure gave the best combination of agricultural and environmental characteristics and could be used without additional fertigation. © 2012 Society of Chemical Industry     

Effect of nitrogen fertilisation on protein content,total fatty acid content and composition of barley (Hordeum vulgare L.) grains

The impact of N-fertilisation level on protein content, total fatty acid (TFA) content and major fatty acid composition of barley grains (cv. Eldorado), grown in a replicated field trial, was investigated. Increasing amounts of N-fertiliser, applied at several stages during the growing season, resulted in a higher protein content and a very slightly lowered TFA content in the grains. Protein and TFA contents were negatively correlated (r=-0.4685). Minor changes of fatty acid composition were found in the decrease of the oleic acid (C18:1) proportion (r=-0.8376) and in the increase of the palmitic acid (C16:0) proportion (r=0.7273). The stearic acid (C18:0) and the linoleic acid (C18:2) proportions were also affected, however, no significant linear correlations with the total N-fertiliser level were obtained. The slow increase in the linolenic acid (C18:3) proportion (r=0.5674) was too small, compared to the residual variance, to be significant. TFA content was positively (P<0.001) correlated with the oleic acid proportion, and negatively (P<0.001) with the palmitic acid proportion. These data suggest that the application of higher amounts of N-fertiliser slightly decreases the total fatty acid content of barley grains, probably due to a decreased synthesis of oleic acid, precursor of the unsaturated C18 fatty acids. The result is a relative increase in palmitic acid.     

Influence of barley variety, timing of nitrogen fertilisation and sunn pest infestation on malting and brewing

BACKGROUND: This paper presents a multivariate approach to investigate the influence of barley variety, timing of nitrogen fertilisation and sunn pest infestation on malting and brewing. Four spring and two winter barley varieties were grown in one location in southern Europe. Moreover, one of the spring varieties was infested with sunn pest, in order to study the effects of this pest on malting quality, and subjected to different nitrogen fertilisation timing regimes. The samples were micromalted, mashed, brewed and analysed. RESULTS: The data showed that even though the two winter barleys seemed to be the best regarding their physical appearance (sieving fraction I + II > 82%), this superiority was not confirmed in the malt samples, which showed low values of Hartong extract (27.1%) and high values of pH (6.07–6.11) and β‐glucan content (12.5–13.2 g kg^?1), resulting in low‐quality beers. The barley sample subjected to postponed fertilisation had a total nitrogen content (19.5 g kg^?1 dry matter) exceeding the specification for malting barley and gave a beer with a low content of free amino nitrogen (47 mg L^?1) and high values of viscosity (1.99 cP) and β‐glucan content (533 mg L^?1). The beer obtained from the barley sample subjected to pest attack had good quality parameters. CONCLUSION: All spring barleys gave well‐modified malts and consequently beers of higher quality than the winter barleys. Moreover, postponed fertilisation was negatively related to the quality of the final beer, and sunn pest infestation did not induce important economic losses in the beer production chain. Copyright © 2010 Society of Chemical Industry     

Effect of residual fertility and direct fertilisation on kernel,protein and oil yield of peanut (Arachis hypogaea L) grown in rice fallows

Kernel (2814–3467 kg ha^?1), protein (555–759 kg ha^?1) and oil (124–1556 kg ha^?1) yields of peanut (Arachis hypogaea L) varied significantly due to the residual effect of organic manures and inorganic fertilisers together. It was also observed that direct application of recommended fertilisers (25 N, 72 P₂O₅ and 37-5 K₂O kg ha^?1) gave the highest kernel (3669 kg ha^?1), protein (786 kg ha^?1) and oil (1606 kg ha^?1) yields. The reduction in kernel, protein and oil yield from the recommended level of fertilisers to half the recommended level of fertilisers was about 16, 15 and 12% while it was about 25, 33 and 27% with no fertiliser. Thus, the results revealed that the nutrients applied partly through organic manures and inorganic fertilisers to Kharif rice exhibits significant residual effects on the succeeding upland crop and hence the fertilisation must be considered not only for individual crops but also for the cropping system as a whole.     

Health biomarkers in a rat model after intake of organically grown carrots

BACKGROUND: Organic food is perceived as being of better quality and healthier than conventional foods although the scientific research on organic foodstuffs is highly contradictory. The aim of the present study was to investigate if intake of carrots from four different cultivation systems grown in two consecutive years would influence various biomarkers of health in a rat model. All rats were fed a diet with 40% carrot content. The carrots were grown under conventional (C), ‘minimalistic’ organic (O1), organic (O2), or ‘very’ organic cultivation systems (O3). A control group (CO) being fed standard rat chow was included. RESULTS: The plasma α‐tocopherol concentration was higher in the O2 carrot‐based diet group than in the C carrot based‐diet group in one year, while all other health biomarkers or nutrient content differences were observed between the CO diet and the carrot‐based diets. CONCLUSION: This well‐controlled field study demonstrated no clear influence of cultivation methods or harvest year on the nutritional quality of carrots or effect of cultivation methods on health‐related biomarkers in a sensitive rat model. However, the experimental set‐up and selected biomarkers could be used as a framework for further studies of health in relation to organic foodstuff. Copyright © 2012 Society of Chemical Industry     

Variation of organic carbon and nitrogen in aggregate size fractions of a paddy soil under fertilisation practices from Tai Lake Region,China

Long‐term changes in agricultural management can affect soil organic carbon (SOC) and nutrient dynamics, which can be monitored by determining the distribution of microbial activity and nutrient pools in soil aggregates of different size fractions. The objective of the present study was to investigate the changes in SOC and total nitrogen (N_t) distribution in aggregates of different size fractions from a paddy soil (Ferric‐accumulic Stagnic Anthrosols) under a long‐term fertilisation trial. Undisturbed samples of topsoil (0–5 and 5–15 cm depths) were collected from a field experiment farm located in Tai Lake Region, China, with the plots receiving no fertiliser (NF), chemical fertilisers (CF), chemical fertilisers with straw return (CFS) or chemical fertilisers plus pig manure (CFM). In the surface layer, SOC and N_t concentrations appeared as a bimodal peak in the 2000–250 and < 2 µm fractions. SOC concentration increased by 38.6, 40.8 and 17.2% and N_t concentration by 30.0, 16.8 and 38.4% in the 2000–250 µm fractions under CFM, CFS and CF respectively as compared with NF treatment. There were slight changes in SOC and N_t in the < 2 µm fractions from different fertilisation plots. Continuous addition of manure or straw increased storage of SOC and N_t mainly in the coarser aggregate fractions. SOC increases due to straw or pig manure application predominated in the 2000–250 µm fractions, with SOC seeming to be physically protected within macro‐aggregates. Thus straw and manure are likely to play an important role in carbon and nitrogen storage in paddy soil under long‐term combined chemical and organic fertilisation. Copyright © 2007 Society of Chemical Industry     

Effect of conventional and organic production systems on the yield and quality of field tomato cultivars grown in Tunisia

BACKGROUND: The agricultural production system and cultivation practices are critical factors in determining yield and food nutritional quality. Controversy remains regarding whether or not organic foods have a nutritional advantage when compared with their conventionally produced counterparts. In this study the effect of conventional and organic production systems on yield, physicochemical and nutritional properties of four field tomato cultivars (Perfectpeel, Rio Grande, Hypeel 108 and Firenze) was determined. In the organic system, different fertiliser combination treatments were used. RESULTS: When production system data were combined, marketable yield was not affected by cultivar. When averaged across cultivars, organic yield was about 63% of conventional yield. The production system affected fruit soluble solids, pH, titratable acidity and firmness only in some cultivars. However, no effect was found on lycopene and total phenolics in all cultivars. In the organic system, fertiliser combination treatments affected tomato yield of Rio Grande and fruit quality of Firenze and Hypeel 108. A general trend of higher quality data was obtained by using mixed compost C2 combined with its extract and codahumus 20. CONCLUSION: The production system affects tomato yield and some fruit quality attributes. The effect on fruit quality varies among cultivars, thus highlighting the need to use a range of varieties in this kind of study. Copyright © 2009 Society of Chemical Industry     

茅岩莓复合催熟剂对干燥黄花菜色泽及营养品质的影响

为促进黄花菜干燥前快速褪绿黄化,解决黄花菜机械干燥制品出现的返青问题,采用茅岩莓、乙烯利和焦亚硫酸钠3种催熟剂复合对黄花菜进行浸泡处理,再用PVC塑料袋密封,在一定温度下贮藏一段时间,对黄花菜的色泽变化和营养品质进行分析测定。结果表明,茅岩莓复合催熟剂浸泡黄花菜30min,50℃密封包装贮藏5h,黄花菜的褪绿黄化效果最好,营养品质最高;茅岩莓是一种具有保健功能的茶饮植物,安全性高于焦亚硫酸钠和乙烯利。     

Effect of heat treatment and individual shrink packaging on quality and nutritional value of bell pepper stored at suboptimal temperature

The goal of this study was to develop a technology for prolonged storage of pepper fruit at low temperature, based on physical treatments and packaging materials. Physical and compositional changes of red bell pepper fruit (Capsicum annuum L. cv.’Selika’) were monitored during 21 days of cold storage (at 2 °C) plus 3 days at 20 °C (market simulation). Fruits were treated with tap and hot water and stored without packaging or sealing each fruit in individual shrink packaging (Cryovac®). This research revealed that individual shrink packaging following prestorage with hot water rinse (55 °C for 15 s) over brushes, significantly reduced weight loss, softening, decay incidence and chilling injury, while maintaining a quality. The wrapped fruit ripened normally (carotenoid content increased) during shelf‐life period, when shifted to 20 °C after unwrapping. This study showed that antioxidant levels of pepper fruit may be preserved during storage.