Browsing by Author "Kawhena, Tatenda Gift"

Now showing 1 - 4 of 4
  • Thumbnail Image
    Item
    Application of dynamic controlled atmosphere technologies to reduce incidence of physiological disorders and maintain quality of 'Granny Smith' apples
    (MDPI, 2021-05-26) Kawhena, Tatenda Gift; Fawole, Olaniyi Amos; Opara, Umezuruike Linus
    The efficacy of dynamic controlled atmosphere technologies; repeated low oxygen stress (RLOS) and dynamic controlled atmosphere-chlorophyll fluorescence (DCA-CF) to control superficial scald development on ‘Granny Smith’ apples during long-term storage was studied. Fruit were stored for 2, 4, 6, 8, and 10 months at 0 °C in DCA-CF (0.6% O2 and 0.8% CO2), regular atmosphere (RA)(≈21% O2 and 90–95% RH), and RLOS treatments: (1) 0.5% O2 for 10 d followed by ultra-low oxygen (ULO) (0.9% O2 and 0.8% CO2) for 21 d and 0.5% O2 for 7 d or (2) 0.5% O2 for 10 d followed by controlled atmosphere (CA) (1.5% O2 and 1% CO2) for 21 d and 0.5% O2 for 7 d. Development of superficial scald was inhibited for up to 10 months and 7 d shelf life (20 °C) under RLOS + ULO and DCA-CF treatments. Apples stored in RLOS + ULO, RLOS + CA, and DCA-CF had significantly (p < 0.05) higher flesh firmness and total soluble solids. The RLOS phases applied with CA or ULO and DCA-CF storage reduced the development of superficial scald by possibly suppressing the oxidation of volatiles implicated in superficial scald development.
  • Thumbnail Image
    Item
    Application of gum arabic and methyl cellulose coatings enriched with thyme oil to maintain quality and extend shelf life of “Acco” pomegranate arils
    (MDPI, 2020-12-01) Kawhena, Tatenda Gift; Tsige, Alemayehu Ambaw; Opara, Umezuruike Linus; Fawole, Olaniyi Amos
    The effects of gum arabic (GA; 1.5% w/v) and methyl cellulose (MC; 1% w/v) enriched with thyme oil (TO; 0.25 and 0.5% v/v) on the quality of “Acco” pomegranate arils were studied. Coating treatments, namely, MC, MC + TO0.5%, MC + TO0.25%, GA, GA + TO0.5% and GA + TO0.25% were applied on arils by dipping, and evaluations were made on physicochemical and microbiological quality, phytochemicals and antioxidant capacity of arils stored (5 ± 1 ◦C, 95 ± 2% RH) for 16 days. Dipping arils in GA or MC, both containing TO (0.5% v/v) significantly (p < 0.0001) reduced weight loss and enhanced antioxidant activity (FRAP) (p = 0.0014). However, dipping arils in GA combined with TO (0.25% v/v) had the highest influence on reducing aril respiration rate compared with other treatments. Overall, results showed that application of coatings (GA + TO0.5% and GA + TO0.25%) reduced total yeast and mould and total plate counts and maintained quality up to 8 days of storage. These findings suggest that either GA + TO0.5% or GA + TO0.25% coatings have the capability to extend storage life of “Acco” pomegranate arils.
  • Thumbnail Image
    Item
    Formulation and application of novel bioactive edible coatings to extend storage and shelf life of pomegranate whole fruit and arils
    (2022-12) Kawhena, Tatenda Gift; Opara, Umezuruike Linus; Fawole, Olaniyi Amos; Tsige, Alemayehu Ambaw
  • Thumbnail Image
    Item
    Optimization of gum arabic and starch-based edible coatings with lemongrass oil using response surface methodology for improving postharvest quality of whole “wonderful” pomegranate fruit
    (MDPI, 2021-04-12) Kawhena, Tatenda Gift; Opara, Umezuruike Linus; Fawole, Olaniyi Amos
    The effects of edible coatings based on gum arabic (GA) (0.5–1.5%), maize starch (MS) (0.5–1.5%), lemongrass oil (LO) (2–4%), and glycerol (GC) (0.5–1%) developed using response surface methodology (RSM) on “Wonderful” pomegranate fruit were studied. After 42 days of storage (5 1 C, 95 2% RH) and 5 days at ambient temperature (20 0.2 C and 60 10% RH), whole fruit were evaluated for weight loss (%) and pomegranate juice (PJ) for total soluble solids ( Brix), titratable acidity (% Citric acid), and antioxidant capacity. The optimization procedure was done using RSM and the response variables were mainly influenced by the concentrations of MS and GA. The optimized coating consisted of GA (0.5%), MS (0.5%), LO (3%), and GC (1.5%) with desirability of 0.614 (0—minimum and 1—maximum). The predicted values of response variables, for the coating were weight loss (%) = 5.51, TSS ( Brix) = 16.45, TA (% Citric acid) = 1.50, and antioxidant capacity (RSA = 58.13 mM AAE/mL PJ and FRAP = 40.03 mM TE/mL PJ). Therefore, the optimized coating formulation is a potential postharvest treatment for “Wonderful” pomegranate to inhibit weight loss and maintain overall quality during storage and shelf-life.