Ultrasonic Cutting as a New Method to Produce Fresh‐Cut Red Delicious and Golden Delicious Apples

Abstract

The fresh-cut or sliced apple market has grown rapidly in recent years due to consumers' demand for fresh, convenient, and nutritious foods. Fresh-cut apples also contributed to increased consumption of fruits among school children. However, not many studies have investigated means to improve the quality of fresh-cut apples. In this study, we explored the use of ultrasound as a new method to cut apples and examined the quality of two apple varieties (Red Delicious and Golden Delicious) cut with ultrasound. Both apple types were cut without (control) and with ultrasound at four amplitudes (0%, 30%, 40%, and 50%) with an ultrasonic knife. Quality attributes, for example, color, pH, polyphenol oxidase (PPO) activity, surface morphology, and sensory characteristics (color, odor, overall acceptability, and off-odor) of the apples right after cutting and during a 2-week storage at refrigeration temperature were compared. With the set up used in this study, both apples cut with ultrasound exhibited a relatively dense and smooth surface morphology with less cell damage compared with the relatively rough surface and more cells damage in the control. An improvement in quality attributes was observed when the ultrasound amplitude was increased from 30% to 50%. The apples cut with ultrasound had a lower PPO activity compared to the control, indicating less browning. In visual quality evaluation, panelists showed higher liking of the apples cut with ultrasound. The ultrasound-assisted cutting has showed promise for producing fresh-cut apples with improved quality, and may be used as an alternative to traditional cutting method.Practical Application: Fresh-cut produce has gained popularity in recent years due to its health benefits. Traditional methods to produce fresh produce use a static stainless steel blade to cut fruits or vegetables, causing chemical or visual quality issues. This study proposed a new method using a blade that vibrates at ultrasonic frequency to cut apples. The results have shown an improvement in the quality of fresh-cut apples. This method may provide a new solution for producing fresh-cut produce to better meet the requirement of consumers for quality products.

Active Edible Films Fortified with Natural Extracts: Case Study with Fresh-Cut Apple Pieces

“…The increasing pH value during storage of Golden Delicious fresh-cut apples caused by metabolic processes were confirmed by previous works [ 38 , 39 ]. Usually, red apples have higher pH values than that of green apples, and these parameters are very important for consumers since they appreciate the balance of sweetness and acidity [ 40 ].…”

Optimisation of Physical and Chemical Treatments to Control Browning Development and Enzymatic Activity on Fresh-cut Apple Slices

“…These enzymes are present in almost all plants, but most abundantly active in fruits such as apples [7,8]. During cutting operations, the fruit cell ruptures allowing oxygen in the air to react with the PPO and substrate thereby causing browning [9]. PPO catalyzes the oxidation of monohydroxy phenols (phenol, tyrosine, p-cresol) to o-dihydroxyphenols (catechol, dopamine, and adrenaline) and dehydrogenation of o-dihydroxyphenols to o-quinones producing melanins which manifest as brown colour in the foods [10,11].…”

Advanced cutting techniques for solid food: Mechanisms, applications, modeling approaches, and future perspectives

“…UVA cutting as a vibration cutting technique can prevent materials from sticking to the blade surface and thus reduce contamination and pollution. UVA cutting technique was performed by Yildiz et al (2019) in Golden Delicious and Red Delicious apples, with a focus on the variation of apple quality indicators immediately and during 14 days of storage at refrigerated temperature. The cutting performances reflected by the appearance and morphology on the section surfaces in Golden Delicious and Red Delicious apples while applying conventional and UVA cutting strategies are shown in Figure 4.…”

“…Although there has been increased research in the field of UVA cutting of foods , research regarding contamination and microbial growth during storage are still rarely F I G U R E 4 Cutting performance of the appearance and morphology on section surface in Golden Delicious and Red Delicious apples by applying conventional and UVA cutting strategies (Yildiz et al, 2019) reported. Therefore, more work should be devoted to filling these gaps.…”