Commodity Systems Assessment Methodology of Postharvest Losses in Vegetable Amaranths: The Case of Tamale, Ghana

A semistructured questionnaire based on the commodity system assessment methodology (CSAM) was used to determine postharvest losses in vegetable amaranths (VA). Fifty producers and retailers were randomly selected from five and four major VA producing areas and markets, respectively, and interviewed. Data obtained were subjected to descriptive statistical analyses. The survey revealed that absence of laws, regulation, incentives, and inadequate technical information affected the production of VA. The utmost preproduction challenge was poor quality seeds with poor seed yield (35%), low viability (19%), and nontrueness (46%). It was noted that some cultural practices including planting pattern and density, irrigation, and fertiliser use had effects on postharvest losses. Some postharvest practices used were cleaning with water, trimming, sorting, and grading. Usually the produce was transported to marketing centers by cars and motor cycle trailers. Generally poor temperature management after harvest was a big challenge for the postharvest handling of VA. The potential of vegetable amaranths as a commodity in the study area can be enhanced by providing the necessary institutional support, incentives, and use of good management practices along the value chain. An interdisciplinary approach and quantification of losses along the chain are recommended for any future study

Interspecific variation in leaf traits, photosynthetic light response, and whole-plant productivity in amaranths (Amaranthus spp. L.)

Photosynthetic light response curve parameters help us understand the interspecific variation in photosynthetic traits, leaf acclimation status, carbon uptake, and plant productivity in specific environments. These parameters are also influenced by leaf traits which rely on species and growth environment. In accessions of four amaranth species (Amaranthus. hybridus, A. dubius, A. hypochondriacus, and A. cruentus), we determined variations in the net photosynthetic light response curves and leaf traits, and analysed the relationships between maximum gross photosynthetic rate, leaf traits, and whole-plant productivity. Non-rectangular hyperbolae were used for the net photosynthesis light response curves. Maximum gross photosynthetic rate (Pgmax) was the only variant parameter among the species, ranging from 22.29 to 34.21 μmol m–2 s–1. Interspecific variation existed for all the leaf traits except leaf mass per area and leaf inclination angle. Stomatal conductance, nitrogen, chlorophyll, and carotenoid contents, as well as leaf area correlated with Pgmax. Stomatal conductance and leaf nitrogen explained much of the variation in Pgmax at the leaf level. At the plant level, the slope between absolute growth rate and leaf area showed a strong linear relationship with Pgmax. Overall, A. hybridus and A. cruentus exhibited higher Pgmax at the leaf level and light use efficiency at the whole-plant level than A. dubius, and A. hypochondriacus. Thus, A. hybridus and A. cruentus tended to be more efficient with respect to carbon assimilation. These findings highlight the correlation between leaf photosynthetic characteristics, other leaf traits, and whole plant productivity in amaranths. Future studies may explore more species and accessions of Amaranthus at different locations or light environments

Alternative Green and Novel Postharvest Treatments for Minimally Processed Fruits and Vegetables

Minimally processed fresh produce is ready to eat and subjected to minimal technology before consumption. Fresh fruits and vegetables (FFVs) are minimally processed commodities that are metabolically active and undergo physiological processes such as ripening and senescence, reducing their quality and shelf life. Postharvest technologies maintain the quality and prolong the shelf life of harvested produce, without which the quality deteriorates such that significant economic loss ensues due to water and nutrients loss, physiological deterioration, biochemical changes, and microbial degeneration. Conventional postharvest treatments such as temperature management, and chemical and gaseous treatments are widely known for controlling postharvest issues in FFVs. However, there are novel and green alternative safe methods that are employed to maintain the postharvest quality and prolong the shelf life of FFVs. This chapter focuses on seven common alternative novel and green postharvest treatments: nitric oxide, ozone, methyl jasmonate, salicylic acid, oxalic acid, calcium, and heat treatments. These treatments are explained and some of their current application on FFVs are discussed and tabularized indicating the optimum treatment conditions reported in the latest scientific publications

Types of indigenous vegetables consumed, preparation, preferences and perceived benefits in Ghana

Indigenous vegetables (IVs) are rich sources of essential nutrients, particularly vitamins and minerals, and other non-nutritive phytochemicals. IVs play a critical role in the food culture of the Ghanaian people. Despite their importance, they have over the years been mostly associated with the resource-poor. In this study, the types of IVs, preparation preferences, frequency of consumption and some perceived benefits ascribed by some Ghanaian consumers (n = 1393) were investigated in a cross-sectional survey. Descriptive analysis and a chi-square test of independence were conducted to summarise and determine the relationship between gender, age and consumption frequency of the IVs. The study identified okra (Abelmoschus esculentus), cocoyam (Xanthosoma sagittifolium) leaves, jute mallow (Corchorus olitorius) and garden egg (Solanum melongena) as the popular IVs consumed by respondents. Among these, about 13.3% of women and 15.3% of men indicated they consume okra. Eight per cent of the women respondents and 6.7% of the men consumed jute mallow. Almost 57% of the respondents said the IVs were used to prepare stew and soup. More than a third (39%) of the respondents indicated that they consumed the IVs either daily or more than once a week. Women respondents’ frequency of IVs consumption was significantly different [X2 (4, n = 1393) = 30.11, p = 0.000] from the men. The frequency of consumption of IVs for the elderly was significantly higher [X2 (12, n = 1393) = 30.53, p = 0.002] as compared to the younger respondents. The main perceived benefits of IVs were nutrition- and health-related. The major barriers to the consumption of IVs were cost, non-availability, palatability and cultural. The IVs were largely wet-cooked and consumed as stews or sauces and soups. These findings form good bases for further empirical studies on the nutritional and other health-benefiting attributes of the specific IVs found in this study for sustainable promotion and utilisation in Ghana