Storage Stability and Consumer Acceptability of Dried Apple: Impact of Citric Acid, Potassium Sorbate and Moringa oleifera Leaf Extract Powder

Abstract

The effects of a dipping solution containing 2.0% citric acid (CA) and 0.1% Moringa oleifera leaf extract powder (MOLEP) (CMO) and another dipping solution with CA at 2.0%, MOLEP at 0.1% and potassium sorbate (PS) at 0.2% (CMOP) on the storage stability over 3 months and consumer acceptability of dried apple slices were evaluated. Microbiological testing (osmophilic yeast, Escherichia coli and yeast and moulds) and total acidity testing were performed and physical tests, namely moisture analysis, water activity (Aw), texture analysis and colour were performed at day 0, day 60 and day 120. Moisture increased over the shelf-life period, which affected the extensibility of the pre-treated dried sliced apples negatively. The CMO pre-treatment was effective in reducing browning and inhibiting microbial growth on the dried apple slices over the storage period. A consumer acceptability test was performed using the nine-point hedonic scale. The dried sliced apples pre-treated with the 2% CA and 0.1% MOLEP powder water solution were acceptable to consumers with regards to colour, texture and taste.

Home-Drying Operation Effect on Moisture Content, Electric Energy Consumption, Ascorbic Acid, Total Polyphenol Content, and Color of Sliced “Fuji” Apples

“…The lowest ECR (2.88 kWh/kg) calculated for our treatment of 50 °C/500 g can be explained by less variation in the moisture content (84.8 to 26.2%) during drying (Figure 5 and Table 3). In this case, more drying time would be required for the dried apple slices to reach the similar moisture content reported by Shewale et al [33] and Arendse and Jideani [28] ranging from 5 to 7.3% (w.b.). Probably the home dehydrator used to obtain sliced "Fuji" apples this research consumes energy levels similar to that produced by an industrial process.…”

“…Chilean food regulations do not establish moisture level requirements for dried fruits, but Argentina proposes a regulation of the quality and identity of dried fruits at the time of packaging that requires humidity lower than 25% [ 27 ]. The Republic of South Africa, via regulation 653, seeks to establish a moisture content limit of <27% for dried fruit intended for sale, which is in relation to the quality, packing, and marketing of products, according to Arendse and Jideani [ 28 ]. The four treatments would allow compliance with international requirements of moisture content for dried fruits.…”

“…On the other hand, the shelf life of sliced apple fruit dried by air cabinet dehydrator (Excalibur, model EXC 10) could be improved with moisture content ranging from 6.0 to 7.3% [ 28 ]. In another research, apple slices were dried using an oven dryer at 40–50°C until the moisture content left was ≤12%, and after, they were stored at 4°C for 25 days.…”

“…Several researches had been evaluating the effect of drying on the color of fresh apples [ 17 – 20 , 22 , 28 , 32 , 33 ]. The difference parameter Δ E between fresh and dried apples in Table 3 shows that low values were obtained with drying at 70°C, which means that both colors most resemble each other.…”

Ultrasound- and Microwave-Assisted Extraction of Pectin from Apple Pomace and Its Effect on the Quality of Fruit Bars

“…The titratable acidity decreases during the storage of the samples from 1.12% (on the first day) to 0.83% expressed as citric acid (360th day), due to the physicochemical transformations of compounds that occur in the fruit bars. The specialized literature confirms that the moisture content in dried fruits is approximately 20%, and the pH varies from 3.1 to 4.0, making them foods with high acidity [94].…”