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Cactus pear fruits are rich sources of nutritional (essential vitamins, amino acids and minerals) and antioxidant compounds (flavonoids, carotenes, betalains, ascorbic acid and quercetin). The fruit is cultivated for fresh markets and also serves as nutraceutical and functional food, finding application in various forms such as juice, jam, wine, syrup and in dairy products. However, short postharvest life and negative perception has contributed to its underutilization in the local context. Total titratable acidity (TTA) and total soluble solids (TSS) are among the desirable attributes used to assess postharvest quality of Cactus pears. A portable near-infrared spectrometer (NIRS) can non-destructively determine the internal quality of Cactus pears' thus reducing postharvest losses. This study evaluated the potential of a handheld NIRS coupled with chemometrics of partial least square regression (PLSR) for rapid, non-destructive, and simultaneous determination of TTA and TSS in intact Cactus pear fruits. Cactus pears at different stages of maturity were sampled from Laikipia county, in Kenya, and immediately subjected to spectral data acquisition and wet-chemistry analyses. The PLSR was used to train and validate predictive models for the determination of TTA and TSS content in intact Cactus pears. The prediction model for TTA gave an R-squared (R2) of 0.73, root mean squared error of prediction (RMSEP) of 0.28% citric acid, and residual predictive deviation (RPD) of 1.97. Additionally, the TSS model resulted in R2 of 0.75, RMSEP of 1.60° Brix, and RPD of 2.06. Overall, these findings highlight the effectiveness of NIRS in non-destructive measurement of TTA and TSS levels in whole Cactus pears. However, with further refinement and optimization of these models, the full potential of this technique for swift and precise assessment of these parameters in whole Cactus pears can be realized. This would greatly benefit farmers and processors by reducing expenses associated with quality assessment and facilitating market entry of Cactus pear derived food products. [ABSTRACT FROM AUTHOR]

The sustainability of fresh fruits and vegetables value chains is challenged by high levels of food loss and waste (FLW) in resource-limited economies. In Kenya, where smallholder farmers dominate the food production sector, FLW in fruits and vegetables is estimated at 30-40%. This study investigated the ecosystem of FLW solution providers in Kenya, examining the challenges faced in developing and scaling interventions, and identifying successful strategies to overcome these barriers. A qualitative approach was employed. Primary data on FLW was obtained from solution providers through key informant interviews. The FLW solution providers were categorized as either successful or partially successful based on their commercial viability and operational tenure. The study utilized purposive sampling and a structured interview guide. The study identified several key challenges faced by FLW solution providers which comprised insufficient technical knowledge in food processing and machine operation, limited financial capacity for both operation and scaling, inconsistent supply of raw materials due to seasonality, competition from established companies and artificial products, slow market penetration, and low product acceptability (for partially successful providers). Successful solution providers employed various strategies to overcome these challenges including partnering with universities, governmental and non-governmental organizations for research, development, and initial financing; undertaking comprehensive technical and commercial viability assessments before scaling; adopting product differentiation to capture diverse markets; utilizing preservation techniques like drying and establishing off-take contracts to counter supply inconsistencies and establishing stable external markets and reliable business to business models. The study also revealed the potential for gender-inclusive impact, as many solution providers tend to employ more women due to the nature of the work. The findings highlight the critical role of partnerships, comprehensive market research, and adaptive strategies in developing successful FLW solutions. The contrast between successful and partially successful solution providers underscores the importance of comprehensive planning, technical expertise, and market-oriented approaches. By learning from successful solution providers and addressing key challenges, stakeholders can create more sustainable and effective interventions to reduce FLW and improve food security and nutrition status, and enhance the livelihoods of smallholder farmers. [ABSTRACT FROM AUTHOR]

Mango is an economically important fruit crop but with a very short shelf life of about 4–9 days in ambient and between 2 and 3 weeks in cold storage. Extending the shelf life and marketing period of mango fruit requires application of quality preservation technologies. This study aimed at evaluating the effect of innovative waxing options on shelf life and postharvest quality of "ngowe" mango fruits stored under different storage conditions. A homogenous sample of mango fruits, variety "ngowe" harvested at mature green stage were subjected to two waxing treatments, namely Shellac or Decco wax™. The waxes were applied by dipping the fruits in wax for five seconds followed by air drying. The waxed fruits were then packed in carton boxes and stored either at ambient room temperature (25°C) or cold room (12°C). Random samples of three fruits from each treatment and storage conditions were taken for measurement of attributes associated with ripening after every 3 and 7 days for ambient and cold storage, respectively. These included cumulative weight loss, respiration, peel firmness, total soluble solids (TSS), total titratable acidity (TTA) and beta carotene content. Results from the study showed that waxing with either Shellac or Decco wax was effective in prolonging shelf life of "ngowe" mango fruits by 3 and 6 days in ambient and cold storage respectively. Untreated fruits in ambient storage lost 5.3% of the initial weight by day 7 compared to an average of 4.5% for the waxed fruit (day 10). Waxed fruits in ambient had low CO2 concentration (59.53 ml/kg hr) compared to a high (88.11 ml/kg hr) CO2 concentration for the untreated fruits. Similarly, other ripening related changes including brix, color, and firmness were significantly slowed down by waxing, especially under cold storage. Findings from this study show the effectiveness of waxing in delaying mango fruit ripening. Waxing can therefore be used to extend the shelf life and marketing period for mango fruit. [ABSTRACT FROM AUTHOR]

BACKGROUND Drought stress is one of the main abiotic stresses that affect crops. It leads to biochemical changes that can have adverse effects on plant growth, development and productivity. African eggplants are important vegetable and fruit crops reported to adapt and thrive well under drought stress. The diversified metabolites arising due to stress have not been well defined. A gas chromatographic-mass spectrometric metabolomic approach was applied to characterize the effect of drought stress on metabolites at different stages of growth. Nineteen accessions were selected for analysis and drought was imposed by withholding water until soil moisture reached 60% field capacity. Fresh leaf tissues were sampled before stress, 2 and 4 weeks after stress and metabolite profiling done. RESULTS Significant changes in metabolite content were observed, and potentially important metabolites with respect to stress responses were characterized. Proline, glutamate, sucrose, fructose and tricarboxylic acid cycle metabolites were shown to be positively correlated with stress. Principal component analysis showed a clear discrimination between the different accessions, growth stages and stress/control conditions. CONCLUSION The results illustrate that drought stress has a significant impact on the concentrations of some metabolites, such as amino acids, sugars and organic acids, which may contribute to drought stress effects and tolerance. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

African eggplants ( Solanum aethiopicum and S. macrocarpon) are among the most economically important and valuable vegetable and fruit crops. They are a major source of biologically active nutritional substances and metabolites which are essential for plant growth, development, stress adaptation and defense. Among these metabolites are the carotenoids which act as accessory pigments for photosynthesis and precursor to plant hormones. Though African eggplants are known to be resistant to various abiotic stresses, the effect of these stresses on secondary metabolites has not been well defined. The objective of this study was to establish the effect of drought stress on carotenoid profiles of nineteen African eggplant accessions selected based on leaf and fruit morphological traits. Stress was achieved by limiting irrigation and maintaining the wilting state of the crops. Fresh leaves were sampled at different maturity stages; before stress, 2 weeks and 4 weeks after stress for carotenoid analysis. The fresh harvested leaf tissues were immediately frozen in liquid nitrogen and ground. Analysis was carried out using a Dionex HPLC machine coupled to Photo Array Detector and Chromeleon software package (Thermo Fisher Scientific Inc, Waltham, Massachusetts, USA). Major carotenoids viz;. Xanthophylls (neoxanthin, violaxanthin, zeaxanthin and lutein) and carotenes ( β-carotene and α-carotene), phytofluene, lycopene, phytoene as well as chlorophylls (chlorophyll-b and Chlorophyll-a) were targeted. The carotenoids increased with maturity stage of the crop. Although the stressed crops reported significantly decreased amount of carotenes, chlorophylls, neoxanthin and violaxanthin, the concentration of zeaxanthin increased with stress whereas lutein had no significant change. Chlorophyll-a was significantly high in all the control accessions. Two accessions reported significantly higher contents of carotenoids as compared to the other accessions. The results of this study indicate that water stress has significant impact on the concentration of some carotenoids and photosynthetic pigments. This will definitely add value to the study of stress tolerance in crops. [ABSTRACT FROM AUTHOR]