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The mango fruit is widely recognized as one of the most delectable, popular, and vital fruit crops in tropical and subtropical regions. Its renowned taste is celebrated worldwide, whether enjoyed fresh or in processed forms. This research was undertaken to assess the efficacy of employing both natural olive leaves extract (OLE) and minimal chemical preservatives (sodium benzoate and potassium sorbate) for preserving mango OLE blend over a 90 days period. The findings demonstrated that the inclusion of OLE effectively preserved the chemical quality and sensory characteristics of mango OLE blend with added chemical preservatives. Results showed that all samples retained total soluble solids between (17.89-20.80°Brix), pH (4.06-4.91), color (6.94 to 8.01), flavor (5.34 to 6.34) and taste (5.59-6.99). The results concluded that OLE can serve as a dual-purpose solution, acting as a natural antioxidant and antimicrobial preservative for refrigerated mango OLE blend. [ABSTRACT FROM AUTHOR]

Background. Longan fruit is a rich source of bioactive compounds; however, enzymatic browning of pericarp and microbial decay have limited its postharvest life. SO2 has widely been used to overcome these limitations; however, due to safety and regulatory concerns, alternative means should be identified. In this study, antioxidant and antimicrobial properties of thymol (TH) essential oil were investigated against the enzymatic browning and decay of longan fruit. Methods. Fruits were coated with TH (4%) for 5 min, sealed in polyethylene (PE) packages and stored at 4 °C for 42 d. Fruits immersed in distilled water (DW) and stored in PE were used as control. Results. TH extended the postharvest life of longan to 42 d than 28 d in DW. TH residues decreased from 142 to 11.17 mg kg-1, while no residues were found at day 42. TH significantly (P = 0.05) reduced the respiration rate, inhibited polyphenol oxidase (PPO) and peroxidase (POD) enzyme activities, sustained high phenols/flavonoids and prevented pericarp browning (BI) than DW. TH also effectively (P = 0.05) maintained the color values, firmness of peel and aril, total soluble solids (TSS), titratable acidity (TA), inhibited decay incidence (DI) and resulted in lower ethanol content than DW. BI as a function of pericarp pH was highly correlated; pH and BI (r=0. 97), with PPO (r=0.93) and with water loss (r=0.99). A high coefficient of correlation of BI was found with the pericarp pH, enzymes, phenolic, water loss and decay incidence with ethanol. TH could be the best alternative to SO2 and other synthetic preservatives. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the effect of food preservatives (potassium sorbate, potassium metabisulphite and sodium benzoate) on the storage stability at ambient temperature (25 ± 5°C) of blended pulp of peach and persimmon. Effect of preservatives on physico-chemical parameters (total soluble solids, pH, titratable acidity, total phenolic compounds, ascorbic acid content and antioxidant activity) and sensory evaluation of blends was carried out. The treatments in this study included BP0 [peach persimmon blend (6:4)], BP1 [peach persimmon blend (6:4) + potassium sorbate (0.1%)], BP2 [peach persimmon blend (6:4) + potassium metabisulphite (0.1%)], BP3 [peach persimmon blend (6:4) + sodium benzoate (0.1%)], BP4 [peach persimmon blend (6:4) + potassium sorbate (0.05%) + potassium metabisulphite (0.05%)], BP5 [peach persimmon blend (6:4) + potassium sorbate (0.05%) + sodium benzoate (0.05%)], BP6 [peach persimmon blend (6:4) + potassium metabisulphite (0.05%) + sodium benzoate (0.05%)], BP7 [peach persimmon blend (6:4) + potassium sorbate (0.033%) + potassium metabisulphite (0.033%) + sodium benzoate (0.033%)]. The results revealed decline (P < 0.05) in pH, total phenolic content, antioxidant activity, ascorbic acid and sensory attributes whereas increase was observed in TSS and titratable acidity. The pH, total phenolic compounds, antioxidant activity and ascorbic acid content decreased from 3.84 to 3.16, 36.18 to 23.08 mg GAE/100g, 85.31 to 50.31 TE/100g and 28.31 to 13.47 mg/100 g respectively. Similarly, the values of titratable acidity and total soluble solids increased from 0.67 to 0.77 % and 9.12 to 10.59 0Brix respectively. On the basis of sensory evaluation BP7 and BP4 obtained maximum mean scores for color, flavor and overall acceptability. From the overall results, it was concluded that (P < 0.05) blended pulp treatment BP7 (blended pulp + 0.033% potassium sorbate + 0.033% potassium metabisulphite + 0.033% was found best among all the treatments. [ABSTRACT FROM AUTHOR]

Pakistan is considered as one of the top ten ranked countries in date palm fruits production. This study was conducted to assess losses at farm, wholesale and retail levels in supply chain of Dhakki dates in D.I. Khan, Pakistan. Furthermore, physical and chemical characteristics of dates were also determined. For the observation of losses all the samples were randomly collected at farm level. Dates were conventionally packaged and transported in open mini trucks to wholesale market and retail out- lets/vendors in Peshawar city and losses were noted. Results indicated that overall percent losses in Dhakki dates at farm level were 29.6%, while losses at wholesale and retail level were observed as 41.33% and 35.33%, respectively. Major factors for causing losses during supply chain are insect's infestation, birds attack, sunburn, cracking, mechanical damage, fermentation, decaying, bruising and fungal attack. Proper determination of physical parameters including linear dimensions, volume, bulk density, porosity and fruit mass can reduce the mechanical injuries, bruising, cracking and decaying of Dhakki dates during picking and sorting at farm level as well as packaging, transportation and storage at wholesale and retail level. Timely estimation of firmness has key role in minimizing bruising and other defects in date fruits. Moreover it is recommended that suitable cushioning materials can play a vital role in packaging of Dhakki dates during entire supply chain. [ABSTRACT FROM AUTHOR]

Persimmon fruit is abundantly found in Khyber Pakhtunkhwa province of Pakistan. Fresh persimmons were pre-treated and dehydrated to minimize their post-harvest losses. For this purpose, the effect of antioxidant agents (citric acid, potassium metabisulfite and ascorbic acid) was studied on the overall quality of sun-dried persimmon fruits. The treatments were T0 (control), T1 (5% citric acid), T2 (3% potassium metabisulfite) and T3 (2% ascorbic acid). The peeled persimmon fruits were treated for 5min with these preservatives and dried under sun up to 15-16% moisture. The effect of these treatments on microbial, physicochemical and sensory were analysed at interval of 30 days for the period of 120 days. Results indicated that a significant increase (P≤0.05) was observed in total soluble solid (TSS) while significant decrease (P≤0.05) was examined in moisture content, water activity, ascorbic acid, pH, total phenolics, mineral content and weight loss. The mean score of judges showed a significant decrease (P≤0.05) in colour, flavour and texture. It could be concluded from this research that 3% potassium metabisulfite (T2) comparatively retained the overall quality of dried persimmon fruit during storage. [ABSTRACT FROM AUTHOR]

The effect of selected calcium salts on post-harvest storage life of fresh plum fruits was assessed under refrigerated storage condition (4±1°C) for 32 days. Three equal lots of fresh plum samples were dipped in 1% (w/v) T1 (calcium chloride), T2 (calcium lactate) and T3 (calcium gluconate) solutions for 30 minutes and compared with T0 (untreated plum fruits). Samples were analyzed for firmness, weight loss, total soluble solids, decay index, pH, acidity, ascorbic acid, fungal analysis and sensory characteristics during storage according to standard methods of AOAC (2000). Mycoflora was tested by standard microbiological method by direct plating method. Study revealed that calcium salts significantly improved physico-chemical and sensory qualities of calcium salt treated plum fruit. Presence of Mucor spp. and Penicillium spp. responsible for decaying untreated apricot fruits but no growth in the preserved lot. Calcium lactate treated samples were more acceptable on the basis of physicochemical and sensory analysis in comparison with calcium chloride and calcium gluconate treated samples. [ABSTRACT FROM AUTHOR]

Wheat flour samples (n=40) in triplicates of two different varieties (fine and super) were collected from various sources (Mills and Chakis) of Hazara Division, KP, Pakistan. Samples were analyzed for nutritional quality parameters (pH, moisture, ash, protein, hardness and wet gluten) by using standard methods and micro, macro and toxic elements by using Atomic Absorption Spectrometry (AAS). All the parameters exhibited significant variations in outcomes of two different sources and two varieties. Low wet gluten (10.70 to 19.33% in Mills and13.73 to 26.23% in Chakkis) and high ash contents (1.73 to 10.86% in Mills and 1.8 to 11.06% in Chakkis) were observed during analysis. The concentrations of the micro and macro elements were found in the following order Mg > Ca > Fe > Zn > Cr > Mn > Cu > Ni while the concentrations of the toxic metals in samples of both the sources were detected in the following order Pb > Cd > As. Different concentrations of toxic, essential elements and physicochemical variations provide basis that a detailed survey should be conducted to assess the nutritional worth and health risks based on staple food among Pakistani population. [ABSTRACT FROM AUTHOR]

Background: Longan fruit is a rich source of bioactive compounds; however, enzymatic browning of pericarp and microbial decay have limited its postharvest life. SO 2 has widely been used to overcome these limitations; however, due to safety and regulatory concerns, alternative means should be identified. In this study, antioxidant and antimicrobial properties of thymol (TH) essential oil were investigated against the enzymatic browning and decay of longan fruit., Methods: Fruits were coated with TH (4%) for 5 min, sealed in polyethylene (PE) packages and stored at 4 °C for 42 d. Fruits immersed in distilled water (DW) and stored in PE were used as control., Results: TH extended the postharvest life of longan to 42 d than 28 d in DW. TH residues decreased from 142 to 11.17 mg kg -1 , while no residues were found at day 42. TH significantly ( P ≤ 0.05) reduced the respiration rate, inhibited polyphenol oxidase (PPO) and peroxidase (POD) enzyme activities, sustained high phenols/flavonoids and prevented pericarp browning (BI) than DW. TH also effectively ( P ≤ 0.05) maintained the color values, firmness of peel and aril, total soluble solids (TSS), titratable acidity (TA), inhibited decay incidence (DI) and resulted in lower ethanol content than DW. BI as a function of pericarp pH was highly correlated; pH and BI ( r = 0. 97), with PPO ( r = 0.93) and with water loss ( r = 0.99). A high coefficient of correlation of BI was found with the pericarp pH, enzymes, phenolic, water loss and decay incidence with ethanol. TH could be the best alternative to SO 2 and other synthetic preservatives., Competing Interests: The authors declare there are no competing interests., (©2021 Khan et al.)