Shelf life of non-industrial fresh mango juice: Microbial safety, nutritional and sensory characteristics

Integrated Fruit Ripeness Assessment System Based on an Artificial Olfactory Sensor and Deep Learning

Artificial scent screening systems, inspired by the mammalian olfactory system, hold promise for fruit ripeness detection, but their commercialization is limited by low sensitivity or pattern recognition inaccuracy. This study presents a portable fruit ripeness prediction system based on colorimetric sensing combinatorics and deep convolutional neural networks (DCNN) to accurately identify fruit ripeness. Using the gas chromatography-mass spectrometry (GC-MS) method, the study discerned the distinctive gases emitted by mango, peach, and banana across various ripening stages. The colorimetric sensing combinatorics utilized 25 dyes sensitive to fruit volatile gases, generating a distinct scent fingerprint through cross-reactivity to diverse concentrations and varieties of gases. The unique scent fingerprints can be identified using DCNN. After capturing colorimetric sensor image data, the densely connected convolutional network (DenseNet) was employed, achieving an impressive accuracy rate of 97.39% on the validation set and 82.20% on the test set in assessing fruit ripeness. This fruit ripeness prediction system, coupled with a DCNN, successfully addresses the issues of complex pattern recognition and low identification accuracy. Overall, this innovative tool exhibits high accuracy, non-destructiveness, practical applicability, convenience, and low cost, making it worth considering and developing for fruit ripeness detection.

Potency of Dimethyl Dicarbonate on the Microbial Inhibition Growth Kinetics, and Quality of Passion Fruit (Passiflora edulis) Juice during Refrigerated Storage

This study aimed to investigate the effectiveness of dimethyl dicarbonate (DMDC) at various concentrations (0-250 ppm) in inhibiting the growth of Escherichia coli TISTR 117 and spoilage microbes in passion fruit juice (PFJ) and its impact on the physicochemical and antioxidant quality of the juice during refrigerated storage. The highest log reduction in the total viable count, yeast/molds and E. coli was attained in PFJ samples with 250 ppm of DMDC (p ≤ 0.05) added. Microbial growth inhibition by DMDC followed the first-order kinetic model with a coefficient of determination (R2) and inhibition constants (k) ranging from 0.98 to 0.99 and 0.022 to 0.042, respectively. DMDC at 0-250 ppm showed an insignificant effect on pH, °Brix, color (L*, a*, b*), ascorbic acid, total phenolic compound (TPC), total flavonoid content, and antioxidant activity (DPPH, FRAP) (p > 0.05). Control (untreated PFJ), DMDC-250 ppm, and pasteurized (15 s at 72 °C) samples were subjected to 27 days of cold storage at 4 °C. A decreasing trend in pH, total soluble solid, ascorbic acid content, DPPH and FRAP values were observed in all the samples during refrigerated storage. However, the DMDC-250 ppm sample showed a better prospect in physicochemical quality changes compared to the pasteurized and untreated control PFJ samples. ΔE values showed marked changes in the control sample than the DMDC-250 ppm and pasteurized samples at 27 days of storage. Additionally, the total viable count and yeast/mold count were augmented during storage, and an estimated shelf-life of the control, DMDC-250 ppm, and pasteurized samples was approximately 3, 24 and 18 days, respectively. In conclusion, DMDC at 250 ppm could ensure microbial safety without affecting the quality attributes of PFJ during 24 days of storage at 4 °C.

Fermented formulation of Silybum marianum seeds: Optimization, heavy metal analysis, and hepatoprotective assessment

BACKGROUND

Fermented formulations are extensively used in Ayurveda due to several benefits like improved palatability, bioavailability, pharmacological potential, and shelf life. These formulations can also quench the heavy metals from the plant material and thus reduce the toxicity. Seeds of Silybum marianum (L.) Gaertn. are widely used for the management of many liver diseases.

STUDY DESIGN AND METHODS

In the present study, we developed a novel fermented formulation of S. marianum seeds and evaluated parameters like safety (heavy metal analysis) and effectiveness (hepatoprotective). As the developed formulation's validation is crucial, the critical process variables (time, pH, and sugar concentration) are optimized for alcohol and silybin content using the Box-Behnken design (BBD).

RESULTS

The response surface methodology coupled with BBD predicted the optimized conditions (fermentation time (28 days), pH 5.6, and sugar concentration (22.04%)) for the development of a fermented formulation of the selected herb. Moreover, the alcohol content (6.5 ± 0.9%) and silybin concentration (26.1 ± 2.1%) were confirmed in optimized formulation by GC-MS and HPTLC analysis. The optimized formulation was also analyzed for heavy metals (Pb, As, Hg, and Cd); their concentration is significantly less than the decoction of herbs. Further, the comparative evaluation of the developed formulation with the marketed formulation also confirmed that the fermented formulation's silybin concentration and percentage release were significantly enhanced. In addition, the developed fermented formulation's percentage recovery of HepG2 cell lines after treatment with CCl4 was significantly improved compared with the marketed formulation.

CONCLUSION

It can be summarized that the developed fermented formulation improves safety and effectiveness compared to other market formulations. Finally, it can be concluded that the developed fermented formulation could be further explored as a better alternative for developing Silybum marianum preparation.

Effect of Thermosonication on the Nutritional Quality of Lapsi (Choerospondias axillaris) Fruit Juice: Application of Advanced Artificial Neural Networks

This study explored the effect of thermosonication on the nutritional properties of lapsi (Choerospondias axillaris) fruit juice. The intent of the present investigation was to process lapsi fruit juice using both thermosonication and thermal pasteurisation and to compare the effects of these treatments on the juice's physicochemical, nutritional, and microbiological qualities. In order to maximise the retention of nutritional properties, enhance juice quality, and boost efficiency, an artificial neural network (ANN) model was also developed to forecast the optimisation of process parameters for the quality of lapsi fruit juice. This study establishes a novel experimental planning method using an ANN to multi-objectively optimise the extraction process and identify the ideal extraction conditions for thermosonication (50, 75, and 100% amplitude at 30, 40, and 50 °C for 15, 30, 45, and 60 min) to augment lapsi juice's nutritional and microbiological properties by improving certain attributes such as ascorbic acid (AA), antioxidant activity (AOA), total phenolic content (TPC), total flavonoid content (TFC), total plate count, and yeast and mould count (YMC). The maximum values for AA (71.80 ± 0.05 mg/100 mL), AOA (74.60 ± 0.28%), TPC (187.33 ± 0.03 mg gallic acid equivalents [GAE]/mL), TFC (127.27 ± 0.05 mg quercetin equivalents [QE]/mL), total plate count (not detected), and YMC were achieved in thermosonicated lapsi juice (TSLJ) under optimal conditions. For AA and TFC, the optimal conditions were 100% amplitude, 40 °C, and 45 min. For AOA and TPC, the optimal conditions were 100% amplitude, 40 °C, and 60 min, and for YMC, the optimal conditions were 100% amplitude, 50 °C, and 60 min. According to the findings, thermosonicated juices have improved nutritional properties, making them an excellent source of bioactive elements for use in both the food and pharmaceutical sectors. According to this study, ANN has been identified as a valuable tool for predicting the effectiveness of lapsi fruit juice extraction, and the application of thermosonication as an approach for lapsi juice preservation could be a potential successor to thermal pasteurisation. This approach can help to minimise or hinder quality degradation while improving the juice's functionality.

Juice Quality Evaluation with Multisensor Systems-A Review

E-nose and e-tongue are advanced technologies that allow for the fast and precise analysis of smells and flavours using special sensors. Both technologies are widely used, especially in the food industry, where they are implemented, e.g., for identifying ingredients and product quality, detecting contamination, and assessing their stability and shelf life. Therefore, the aim of this article is to provide a comprehensive review of the application of e-nose and e-tongue in various industries, focusing in particular on the use of these technologies in the fruit and vegetable juice industry. For this purpose, an analysis of research carried out worldwide over the last five years, concerning the possibility of using the considered multisensory systems to test the quality and taste and aroma profiles of juices is included. In addition, the review contains a brief characterization of these innovative devices through information such as their origin, mode of operation, types, advantages and disadvantages, challenges and perspectives, as well as the possibility of their applications in other industries besides the juice industry.

Optimization of strains for fermentation of kiwifruit juice and effects of mono- and mixed culture fermentation on its sensory and aroma profiles

In this study, a quality evaluation model of fermented kiwifruit juice (KJ) based on strain growth characteristics, sensory quality and functional characteristics was established by PCA, and the effects of mono- and mixed culture fermentation on the sensory and aroma profiles of KJ were comparatively studied. Experiments determined that L. brevis (LB) was the optimal strain for monoculture fermentation, and L. plantarum (LP2):LB = 1:2 was the optimum ratio for mixed fermentation. The results showed that lactic acid bacteria (LAB) fermentation significantly reduced the pH, soluble solid content and lightness, and improved its functional characteristics and viscosity. Mixed culture fermentation was superior to monoculture fermentation in terms of colony counts, sensory quality and viscosity. In general, after LAB fermentation, the concentrations of esters, ketones, alcohols and terpenoids in KJ increased significantly, while the concentrations of aldehydes decreased significantly. The production of esters and terpenoids was more strongly promoted by monoculture fermentation, while mixed culture fermentation promoted the production of more ketones and alcohols. 2,5-octanedione and 1-octen-3-ol could be the characteristic aroma compounds of mixed fermented KJ.

Comprehensive evaluation of the effect of five sterilization methods on the quality of black carrot juice based on PCA, TOPSIS and GRA models

The effect of thermal pasteurization (TP), high temperature long time (HTLT), ultra-high temperature instantaneous (UHT), high hydrostatic pressure (HHP) and thermosonication (TS) sterilization on the physicochemical, sensory and functional properties of black carrot juice (BCJ) were studied. And for the first time, the comprehensive quality of sterilized BCJ was quantified by mathematical modeling. UHT was the least suitable sterilization method for BCJ resulting from the most severe deterioration in functional properties. TS had adverse effects on sensory and physicochemical properties, but significantly increased the total flavonoids and anthocyanins contents (p < 0.05) and showed the strongest antioxidant activity, making it a nutritional high-value processing method. TP and HHP balanced the improvement of sensory properties and the retention of functional properties, which were the most suitable sterilization methods for BCJ. This study determined the optimal sterilization methods of BCJ, and provided a scientific solution for the screening of high quality processing methods.

How to comprehensively improve juice quality: a review of the impacts of sterilization technology on the overall quality of fruit and vegetable juices in 2010-2021, an updated overview and current issues

Fruit and vegetable juices (FVJ) are rich in nutrients, so they easily breed bacteria, which cause microbial pollution and rapid deterioration of their quality and safety. Sterilization is an important operation in FVJ processing. However, regardless of whether thermal sterilization or non-thermal sterilization is used, the effect and its impact on the overall quality of FVJ are strongly dependent on the processing parameters, microbial species, and FVJ matrix. Therefore, for different types of FVJ, an understanding of the impacts that different sterilization technologies have on the overall quality of the juice is important in designing and optimizing technical parameters to produce value-added products. This article provides an overview of the application of thermal and non-thermal technique in the field of FVJ processing over the past 10 years. The operating principle and effects of various technologies on the inactivation of microorganisms and enzymes, nutritional and functional characteristics, physicochemical properties, and sensory quality of a wide range of FVJ are comprehensively discussed. The application of different combinations of hurdle technology in the field of FVJ sterilization processing are also discussed in detail. Additionally, the advantages, limitations, and current application prospects of different sterilization technologies are summarized.

Effect of Multi-Mode Thermosonication on the Microbial Inhibition and Quality Retention of Strawberry Clear Juice during Storage at Varied Temperatures

Strawberry juice, which is rich in nutrients and charming flavor, is favored by consumers. To explore whether multi-mode thermosonication (MTS) can ensure the quality stability of strawberry clear juice (SCJ) during storage, the effects of microbial inhibition, enzyme activity, and physicochemical properties of SCJ pretreated by MTS were evaluated during storage at 4, 25, and 37 °C in comparison with thermal pretreatment (TP) at 90 °C for 1 min. The MTS, including dual-frequency energy-gathered ultrasound pretreatment (DEUP) and flat sweep-frequency dispersive ultrasound pretreatment (FSDUP), were conducted at 60 °C for 5 and 15 min, respectively. Results showed that the total phenols, flavonoids, anthocyanins, ascorbic acid, and DPPH free radical scavenging ability of SCJ decreased during the storage period. The control sample of SCJ was able to sage for only 7 days at 4 °C based on the microbiological quality, while the FSDUP and DEUP group extended the storage period up to 21 and 14 days, respectively. The polyphenol oxidase in SCJ pretreated by MTS did not reactivate during the storage period. The MTS remarkably (p < 0.05) reduced the color deterioration, browning degree, and nutrient degradation during the storage period. Moreover, the FSDUP group exhibited the maximum shelf life with a minimum loss of quality, demonstrating that it was the most suitable processing method for obtaining high-quality SCJ. It can be concluded that the MTS has the potential to inhibit enzymatic browning, inactivating microorganisms, preserve original quality attributes, and prolong the shelf life of SCJ.

Research on the Consumption Trend, Nutritional Value, Biological Activity Evaluation, and Sensory Properties of Mini Fruits and Vegetables

Mini fruits and vegetables (MFV) are pocket fruits and vegetables whose shape and volume are significantly smaller than those widely sold and well-known normal fruits and vegetables (NFV) on the market. Through the research on the market status and consumption trends of MFV, it was found that MFV have recently become a new market favorite. However, compared with NFV, there was found to be no relevant data on sensory quality, nutritional value, safety, etc. of MFV; this could indicate low consumer awareness of MFV, which in turn affects their planting and sales choices, as well as the market scale remaining small. In this context, six MFV with high degree of marketization were selected and compared with their corresponding NFV to evaluate the nutritional value, biological activity, and sensory properties. The results showed the nutritional value of MFV to be mainly related to their species. The nutritional value of MFV derived from immature, tender vegetables was generally lower than that of mature NFV. For example, the content of zeaxanthin in normal maize was 0.43 mg/kg, which was about 2.87 times that of mini maize (0.15 mg/kg). For newly cultivated mini varieties, their nutritional value often had different trends and rules compared with NFV. The nutritional value obtained by consuming MFV is not equal to that obtained by consuming the corresponding NFV of the same weight.