Determination of Biochemical Contents of Fresh, Oven-Dried, and Sun-Dried Peels and Pulps of Five Apple Cultivars (Amasya, Braeburn, Golden Delicious, Granny Smith, and Starking)

Zeynep Ergün,Philippe Jeandet

doi:10.1155/2021/9916694

Abstract

This study aimed to investigate the biochemical compounds of five different apple cultivars (Amasya, Braeburn, Golden Delicious, Granny Smith, and Starking) grown in the same location and to reveal the differences between peel and pulp in the fresh, oven-dried, and sun-dried samples. Sugar and organic acid contents were analyzed through high-performance liquid chromatography. Besides, antioxidant activity, total flavonoid, and total phenolic contents were analyzed with a spectrophotometer. The results of these analyses showed that the compounds varied between peel and pulp and among fresh, oven-dried, and sun-dried samples. The largest level of total flavonoid was found in Amasya oven-dried peel, and the largest total phenol, antioxidant activity, fructose, and total sugar levels were observed in Amasya sun-dried peel. Moreover, the largest L-ascorbic acid was detected in Amasya oven-dried pulp. Granny Smith oven-dried pulp was rich in citric, succinic acids, and glucose. Braeburn sun-dried pulp, Golden Delicious oven-dried pulp, and Granny Smith sun-dried pulp contained the largest sucrose, malic acid, and total soluble solids levels, respectively. For data interpretation, t-test, ANOVA, Duncan’s test, Kruskal–Wallis H test, and principal component analysis were performed. The peel contained significantly higher total flavonoid, total phenol, and antioxidant activity than pulp. Moreover, among fresh, oven-dried, and sun-dried samples, total phenol, succinic acid, malic acid, and L-ascorbic acid significantly differed. As a whole, the pulp was rich in sugars. The results provide valuable information on the food quality parameters of five different apple cultivars. It was demonstrated that consuming apple with its peel is healthier (in terms of total flavonoid, total phenol, antioxidant activity parameters, and L-ascorbic acid), and drying (especially the sun-drying method) is an effective food storage method for apples.

Highlights

Fruits are one of the main nutrition sources in the daily human diet. e quality of the fruits has a substantial effect on the decision-making process of the consumers
Biochemical characteristics are ranked among the inner-quality determiners of fruits, as well as increasing outer quality. is study aims to reveal the biochemical characteristics of five different apple cultivars and to make a comparison between fresh, open-air-dried, and oven-dried peel and pulp samples of these varieties. is study focuses on the parameters of total phenols, total flavonoids, sugars, organic acids, and total soluble solids (TSS) among other biochemical characteristics
In the malic acid content list, Granny Smith sun-dried pulp, Braeburn sun-dried pulp, and Starking sundried pulp were the first three, and the Golden Delicious fresh peel, Granny Smith fresh peel, and Braeburn fresh peel were the last three ones. e previous studies argue that the dominant organic acid is malic acid. e results of this study are nearly uniform for Granny Smith [33]. e organic acid content results differed from the former studies for Amasya [33], Granny Smith [33], Braeburn [34], Starking [35], and Golden Delicious [36, 37]. e main result of this difference might be genotypic, weather, and soil differences [2, 38]

Summary

Introduction

Fruits are one of the main nutrition sources in the daily human diet. e quality of the fruits has a substantial effect on the decision-making process of the consumers. Apple (Malus domestica Borkh.) is one of the members of the Rosaceae family and has been consumed by humans since the early ages It is one of the most frequently consumed fruits [1]. Pectin, sugar, acids, and antioxidants containing in apples generally have positive effects on human health [2,3,4]. Some diseases such as cancer, cardiovascular disease, asthma, and diabetes can be prevented through some biochemical compounds of apple [5,6,7,8]. China, the USA, Italy, Chile, and New Zealand were the largest apple sellers in the same year

Methods

Results

Conclusion