Journal of the Science of Food and Agriculture最新文献

Background: Cereal-legume intercropping provides a solution for achieving global food security, but the mechanism of greenhouse gas emissions and net ecosystem economic benefits of maize-soybean relay intercropping are poorly understood. Hence, we conducted a two-factor experiment to investigate the effects of cropping systems, containing maize-soybean relay intercropping (IMS), monoculture maize (M) and monoculture soybean (S), as well as three nitrogen levels at 0 (N0), 180 (N1), 240 (N2) kg N ha^-1 on crop grain yield, greenhouse gas emissions, soil carbon stock and net ecosystem economic benefit (NEEB).

Results: The average grain yield of IMS (7.7 t ha^-1) increased by 28.5% and 242.4% compared with M (6.0 t ha^-1) and S (2.2 t ha^-1). The land equivalent ratio (LER) of IMS was 2.0, which was mainly contributed by maize (partial LER: 1.2) rather than soybean (partial LER: 0.8). Although the total grain yield of IMS remarkably enhanced by 43.6% and 45.5% in N1 and N2 contrast in N0, the LER was 37.5% and 38.6% lower in N1 and N2 than in N0. The net global warming potential (GWP) of maize and soybean was 11.6% and 1.8% lower in IMS than in the corresponding monoculture, which resulted from a decline in GWP and enhanced soil organic carbon stock rate. Moreover, NEEB was 133.5% higher in IMS (14 032.0 Chinese yuan per year) than in M, mainly resulting from an increase in total economic gains and a decline in GWP cost. A more robust response in yield gain rather than total costs to N inputs of IMS led to 46.8% and 48.3% higher NEEB in N1 and N2 than in N0.

Conclusion: Maize-soybean relay intercropping with 180 kg N ha^-1 application can obtain yield advantages without raising environmental costs, which provides an approach to achieving sustainable agricultural production. © 2024 Society of Chemical Industry.

Coconut palm (Cocos nucifera) is a treasured tree of the tropics, with every part put to use. The edible portions are loaded with diverse nutrients and nutraceutical ingredients. While the unique mineral profile of the liquid endosperm, the low-glycemic inflorescence sap (neera) and the medium-chain triglyceride fraction of coconut oil are better recognized, other fractions such as the haustorium remain underexplored. Overall, it is evident that, globally, the present status of coconut value addition is conventional, limited to a handful of products, and novel products hold a promising scope. A massive fraction of global coconut production goes for culinary and religious purposes. In the article, value-added products from coconut are classified into conventional and non-conventional products, with the latter in focus. Based on the part from which it is collected, all products have been categorized as haustorium-based, inflorescence-based, kernel-based and water-based products. For each non-conventional product introduced, its production approach and unique application range are highlighted. Given its health-promoting capabilities, characteristic sensorial attributes, wide application range and technological advancements, coconuts are increasingly being recognized around the world, even in regions that do not cultivate them; this applies to non-food products as well. In the context of value-added products from coconuts, this decade has witnessed a surge in research and commercial interest considering the inclusion of coconut as an ingredient in several food and nutraceutical products. The future will certainly consider regulatory protocols and standards, better documentation of the health impact of coconut-based diets, and the sustainability of coconut production, processing and consumption. © 2024 Society of Chemical Industry.

Background: The peel from Liangping pomelo (Citrus maxima cv. Liangpin Yu) is generally discarded as waste during post-harvest handling and process, resulting in environmental pollution and waste. Pectin is the major component in pomelo peels and yields significant economic advantages. Thus, developing pomelo peel pectin (PPs) might be a feasible strategy to reduce environmental pollution caused by pomelo peel.

Results: The optimized PPs yield was 156.5 ± 2.5 g kg^-1 under the inoculum size of 100 mg g^-1, liquid-solid ratio of 31 mL g^-1, fermentation time of 64 h, and fermentation temperature of 39 °C. PPs-6Aa, a pectin fraction from PPs purified with DEAE-52 cellulose, Sephadex G-100 and Sephadex G-75 column chromatography, showed higher α-glucosidase inhibitory activity, with an IC₅₀ of 0.12 ± 0.03 mg mL^-1. It was a high-methoxyl HG-type pectin of 42.8 kDa, and its repeat unit was →4)-α-GalpA-6-OMe-(1→4)-α-GalpA-6-OMe-(1→. Additionally, its α-glucosidase inhibitory activity might be related to hydrogen bonds formed with Lys-156, Glu-277, His-280, Asp-307, Arg-315, Asn-350, Asp-352 and Glu-411, and to hydrophobic interactions formed with Ser-157, Tyr-158, Asp-233, Gln-239, Ser-240, Phe-303, Thr-306, Leu-313, Phe-314, Gln-353 and Arg-442.

Conclusion: These findings provide structural and bioactivity information on pectin from Liangping pomelo peel, which could be beneficial for the development of functional foods and pharmaceuticals. © 2024 Society of Chemical Industry.

Background: The organoleptic profile of an olive oil is a fundamental quality parameter obtained by human sensory panels. In this work, a portable electronic nose was employed to predict the fruity aroma intensity of 199 olive oil samples from different Spanish regions and cultivar varieties ('Picual', 'Arbequina', and 'Cornicabra'), with special emphasis in testing the robustness of the predictions versus cultivar variety variability. The primary data given by the electronic nose were used to obtain two different feature vectors that were employed to fit ridge and lasso regressions models to two datasets: one consisting of all the samples and another just the cv. Picual samples.

Results: The results obtained showed mean average error (MAE) values below 0.88 in all cases, with an MAE of 0.67 for the 'Picual' model. These MAE values and the similarities in the model parameters fitted for the different data folds are in agreement with the results obtained in previous studies.

Conclusion: The large number of samples analyzed and the results obtained show the robustness of the approach and the applicability of the methods. Also, the results suggest that better performance can be obtained when specific models are fitted for particular cultivars. Overall, the proposed methods are capable of providing useful information for a fast screening of the fruity aroma intensity of olive oils. © 2023 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Background: Polyphenols have long been used to evaluate grape and wine quality and it is necessary to measure them throughout various winemaking stages. They are currently assessed predominantly through analytical methods, which are characterized by time-consuming procedures and environmentally harmful practices. Non-destructive spectroscopy-based devices offer an alternative but they tend to be costly and not readily accessible for smaller wineries. This study introduces the initial steps in employing a portable, user-friendly, and cost-effective visible (VIS) spectrophotometer prototype for direct polyphenol measurement during winemaking.

Results: Grapes (cv Syrah, Bobal, and Cabernet Sauvignon) at different maturation stages were fermented with or without stems. Throughout fermentation, parameters such as color intensity, total polyphenol index, total anthocyanins, and tannins were monitored. Concurrently, VIS spectra were acquired using both the prototype and a commercial instrument. Chemometric approaches were then applied to establish correlation models between spectra and destructive analyses. The prototype models demonstrated an acceptable level of confidence for only a few parameters, indicating their lack of complete reliability at this stage.

Conclusions: Visible spectroscopy is already utilized for polyphenol analysis in winemaking but the aspiration to automate the process in wineries, particularly with low-cost devices, remains unrealized. This study investigates the feasibility of a low-cost and user-friendly spectrophotometer. The results indicate that, in the early stages of prototype utilization, the goal is attainable but requires further development and in-depth assessments. © 2024 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Background: In the present study, the optimization of ultrasound-assisted alkaline extraction (UAAE) and isoelectric precipitation (IEP) was applied to white button (WBM) and oyster (OYM) mushroom flours to produce functional spray dried mushroom protein concentrates. Solid-to-liquid ratio (5-15% w/v), ultrasound power (0-900 W) and type of acid [HCl or acetic acid (AcOH)] were evaluated for their effect on the extraction and protein yields from mushroom flours submitted to UAAE-IEP protein extraction.

Results: Prioritized conditions with maximized protein yield (5% w/v, 900 W, AcOH, for WBM; 5% w/v, 900 W, HCl for OYM) were used to produce spray dried protein concentrates from white button (WBM-PC) and oyster (OYM-PC) mushrooms with high solids recovery (62.3-65.8%). WBM-PC and OYM-PC had high protein content (5.19-5.81 g kg^-1), in addition to remarkable foaming capacity (82.5-235.0%) and foam stability (7.0-162.5%), as well as antioxidant phenolics. Highly pH-dependent behavior was observed for solubility (> 90%, at pH 10) and emulsifying properties (emulsification activity index: > 50 m² g^-1, emulsion stability index: > 65%, at pH 10). UAAE-IEP followed by spray drying increased surface hydrophobicity and free sulfhydryl groups by up to 196.5% and 117.5%, respectively, which improved oil holding capacity (359.9-421.0%) and least gelation concentration (6.0-8.0%) of spray dried mushroom protein concentrates.

Conclusion: Overall, the present study showed that optimized UAAE-IEP coupled with spray drying is an efficient strategy to produce novel mushroom protein concentrates with enhanced functional attributes for multiple food applications. © 2024 The Author(s). Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Background: Xiushui Ninghong tea (XSNH) has a long history and is renowned both in China and internationally. Based on different processing techniques, XSNH can be classified into Ninghong Congou, Ninghong Tea Jinhao, Ninghong Tea Longxucha and other types. To investigate the differences in nutrient compounds and mineral element contents among various types of XSNH, 34 samples from seven types were collected, primarily from tea-producing areas.

Results: Statistical analysis indicated no significant differences in the contents of crude polysaccharides, K, Mg and Fe, whereas significant differences were observed in the levels of moisture, free amino acids, caffeine, tea polyphenols, thearubigin, theaflavins, Zn, P, Mn, Cu and Se. The data were analyzed using various statistical methods such as hierarchical cluster analysis, principal component analysis and partial least squares discriminant analysis. Characteristic compounds and elements such as theaflavin, Se, free amino acids, P and tea polyphenols were identified as key differential components for distinguishing different sample types.

Conclusion: Our research has highlighted the differences in chemical indicators among various types of XSNH, providing a crucial theoretical basis for the future classification and grading of XSNH quality. © 2024 Society of Chemical Industry.

Background: Polyphenols are a group of compounds found in grapes, musts, and wines. Their levels are crucial for grape ripening, proper must fermentation, and final wine characteristics. Standard chemical analysis is commonly used to detect these compounds, but it is costly, time consuming, and requires specialized laboratories and operators. To address this, this study explores a functionalized acoustic sensor for detecting oenological polyphenols.

Results: The method involves utilizing a quartz crystal microbalance with dissipation monitoring (QCM-D) to detect the target analyte by using a gelatin-based probe layer. The sensor is functionalized by optimizing the probe coverage density to maximize its performance. This is achieved by using 12-mercaptododecanoic acid (12-MCA) to immobilize the probe onto the gold sensor surface, and dithiothreitol (DTT) as a reducing and competitive binding agent. The concentration of 12-MCA and DTT in the solutions is varied to control the probe density. QCM-D measurements demonstrate that the probe density can be effectively adjusted using this approach, ranging from 0.2 × 10¹³ to 2 × 10¹³ molecules cm^-2. This study also investigates the interaction between the probe and tannins, confirming the ability of the sensor to detect them. Interestingly, the lower probe coverage achieves higher detection signals when normalized to probe immobilization signals. Moreover, significant changes in mechanical properties of the functionalization layer are observed after the interaction with samples.

Conclusion: The combination of QCM-D with gelatin functionalization holds great promise for future applications in the wine industry. It offers real-time monitoring capabilities, requires minimal sample preparation, and provides high sensitivity for quality control purposes. © 2024 Society of Chemical Industry.

Background: Previous studies have demonstrated that the addition of chitosan can improve the quality and functional properties of meat products. However, the underlying mechanism remains unclear. In this study, the effect and mechanism of the addition of chitosan on the gel properties of myofibrillar protein (MP) were investigated.

Results: The results indicated that the gel strength and the water-holding capacity of MP-chitosan gel increased significantly when chitosan was added at 2.5-10 mg mL^-1. Myofibrillar protein samples with 10 mg mL^-1 added chitosan exhibited the highest elasticity and viscosity during gel formation and strengthening. The addition of chitosan also caused a modification in both the secondary and tertiary structure of MP, resulting in an enhanced exposure of hydrophobic and sulfhydryl groups in comparison with the control. Chitosan inhibited the conversion of immobilized water into free water and the formation of water channels during the thermal gelation process of MP. The denaturation enthalpy (ΔH) of myosin decreased as the concentration of chitosan exceeded 5 mg mL^-1. The microstructure showed that the incorporation of chitosan (5-10 mg mL^-1) facilitated the formation of compact and well organized MP gel networks.

Conclusion: The addition of chitosan can enhance the functional properties of meat protein and facilitate heat-induced gelation, making it a promising ingredient for improving the quality of processed meat products. © 2024 Society of Chemical Industry.

Background: During the processing of spent coffee grounds (SCGs) several residues are obtained, which are mostly disposed of in landfills. There is an urgent need for a comprehensive waste management strategy for these residues. This study evaluates the potential of SCGs as a biofertilizer by assessing their effects on lettuce leaves and the release of antioxidants following in vitro digestion and fermentation.

Results: Lettuce plants were grown with different amounts of SCGs (0-150 g kg^-1) in the substrate. High SCG concentrations in the soil generated lighter colored tissues, a decrease in the green color, less root development, and lower dry weight of leaves (P < 0.05). The SCG levels also affected the release of antioxidants by the final product. This effect was more pronounced in the digested fraction: applying the Ferric Reducing Antioxidant Power (FRAP) method, the addition of SCGs from 10 g kg^-1 to 125 g kg^-1 increased the amount of antioxidant from 43.88 ± 4.81 to 105.96 ± 29.09 μmol Trolox g^-1 of dry weight (P < 0.05). The Indigo Carmine Reducing Capacity (IC_RED) method also showed a similar trend, but in this case the highest value was obtained with 150 g kg^-1 of SCGs (16.41 ± 3.93 mmol catechin g^-1 of dry weight) (P < 0.05). Moreover, in the fermented fraction a significant increase in the antioxidant released was found with low levels of SCG(P<0.05), while lettuces fertilized with intermediate amounts of SCGs (25 and 50 g kg^-1) presented the highest amount of insoluble antioxidant (P < 0.05).

Conclusion: A compromise should be found in order to achieve a product with a high antioxidant capacity and an acceptable visual quality. © 2024 Society of Chemical Industry.