Evaluation of the quality features of electrospray-coated pineapple slices with pomegranate and grape seed oil-enriched emulsions

The quality characteristics of pineapple slices coated with emulsions enriched with pomegranate seed oil (PSO) and grape seed oil (GSO) by electrospray coating (ESC) and dip-coating (DC) methods were investigated. The ESC method was evaluated as an alternative to conventional DC. Pineapple slices were stored in clear polystyrene cups for seven days at 5 °C and 80% RH. The weight loss (%), pH, titratable acidity, color, firmness, total antioxidant activity (TAA), total phenolic content (TPC), microbiological, and sensory qualities of fresh-cut pineapple slices were evaluated. Coated samples had significantly lower weight loss values than the non-coated samples after 7 days of storage. The usage of GSO-enriched emulsion with the ESC method was found to be more successful in preserving the titratable acidity. Although all the samples exhibited a significant decrease in yellowness (b*), the electrospray-coated pineapple slices had the highest. Incorporating GSO into the emulsions helped protect the tissue of the fresh-cut pineapples, regardless of the coating method used. The TPC and TAA values of the samples coated by the ESC method with emulsions enriched with PSO showed a lower decrease compared to other treatments. It was determined that the ESC method was more successful in preserving the sensory qualities of fresh-cut pineapples. These findings suggested that using ESC as a coating method with EO-enriched emulsions has positive effects on the quality features of fresh-cut pineapples.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-023-05839-4.

Prolonging the shelf life of fresh-cut guava (Psidium guajaya L.) by coating with chitosan and cinnamon essential oil

This study investigated the effect of a coating of chitosan (CH) and cinnamon essential oil (CEO; 0-1 %) on the quality attributes of fresh-cut guava (Psidium guajaya L.) during storage at 4 ± 1 °C for 17 days, with uncoated fresh-cut guava used as control. The CH coating significantly (p < 0.05) delayed changes in weight loss, firmness, colour, total soluble solids and titratable acidity compared to the control sample. Furthermore, the effects were more prominent with the incorporation of higher CEO concentrations. The bacterial, yeast and mould counts were also significantly lower (p < 0.05) in the CH-coated samples than in the control, with the coating containing 1 % CEO exhibiting the best quality preservation effect. In addition, CH and CEO coatings extended the shelf life of fresh-cut guava up to 17 days compared to the control sample (shelf life of only 3 days). In conclusion, combining CH and CEO as a coating matrix effectively preserves the quality and enhances fresh-cut guava's shelf life.

Effects of konjac glucomannan/pomegranate peel extract composite coating on the quality and nutritional properties of fresh-cut kiwifruit and green bell pepper

The effects of an edible coating, based on konjac glucomannan (KG) incorporated with pomegranate peel extracts (PE), on the physicochemical and nutritional properties of fresh-cut kiwifruit and green bell pepper during storage were investigated. The optimal extract time (40.6 min), temperature (54.5 °C), and ultrasound power (255.5 W) with response surface method, provided a high total antioxidant activity (TAA) of (92.31 ± 1.43)%. Fresh-cut kiwifruit and green bell pepper were coated by dipping using five treatments (distilled water, ascorbic acid, KG, PE, KG + PE), packed into polymeric film and stored for 8 days at 10 °C. Distilled water treatment was used as control. KG + PE treatment resulted in the highest total soluble solid and titratable acidity in fresh-cut kiwifruit, while the maximum firmness in fresh-cut green bell pepper. The weight loss was both effectively decreased in samples treated with KG or KG + PE. All samples treated with KG + PE had significantly higher contents of chlorophyll, ascorbic acid, total phenolic and TAA than others. Moreover, the KG + PE group had the lowest counts of microorganisms in all samples. KG coating incorporated with PE was proved to be efficient in maintaining the physico-chemical and nutritional properties of fresh-cut kiwifruit and green bell pepper during low temperature storage compared with control.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at 10.1007/s13197-021-05006-7.

Effects of polysaccharide-based edible coatings enriched with dietary fiber on quality attributes of fresh-cut apples

Little information is available regarding the incorporation of dietary fiber into edible films and coatings. In this work, apple fiber and inulin were incorporated into polysaccharide-based (alginate, pectine and gellan gum) edible coating formulations and their effects on the quality attributes of fresh-cut apples were evaluated. Antioxidant properties, color, firmness, sensory quality and microbial growth of fresh-cut apple were studied during 16 days of storage at 4 °C. Results show that dietary fiber extracts incorporated to gellan gum, pectin and alginate-based coatings together with calcium chloride and ascorbic acid successfully maintained the firmness and color of coated fresh-cut apples in comparison with uncoated control samples, which presented severe texture softening and browning. The firmness of apple pieces coated with polysaccharide-based coating formulations incorporating apple fiber doubled, and sometimes tripled, that of uncoated samples. Any of the assayed coatings exhibited a positive effect on the sensory properties of fresh-cut apples. The incorporation of apple fiber, together with the use of ascorbic acid, contributed to keep the antioxidant potential of the fruit at least during the first week of storage. Furthermore, gellan gum coatings had a marked effect in reducing mesophilic and psychrophilic counts on fresh-cut apples throughout storage regardless the addition of dietary fibers. The results achieved demonstrate the feasibility of the addition of dietary fiber to edible coating formulations for increasing the nutritional value of fresh-cut apples without compromising their fresh-like quality attributes.

Effect of soaking in noni (Morinda citrifolia) juice on the microbiological and color behavior of Haden minimally processed mango

The purpose of this study was to evaluate the effect of soaking in noni juice on the microbiological and color behavior of minimally processed mango. Two batches of Haden mango cubes were treated by immersion in noni juice for 2.5 or 5.0 min. Each batch was packed in polypropylene boxes and stored at 6 °C for up to 15 days; in addition, a control group of mango cubes was prepared by immersion in sterile water for the same duration. According to the results, the soaking of mango cubes in noni juice had an antimicrobial effect on mesophilic aerobic bacteria, molds and yeasts during storage at 6 °C for 15 days, without significantly (P < 0.05) affecting the CIE L*, a*, b*, chroma and hue angle values, in comparison with the control after 12 days of storage. The noni juice soaking treatment was demonstrated to be a potentially valuable technology for decontamination of fresh-cut fruit surfaces.