Apples are one of the most highly consumed fruits globally, with estimations that almost 88 million tonnes of apples are produced worldwide each year. As a result of this popularity, consumers have extremely high expectations of the sensory quality of the apples they consume. Improving the quality of apples provides a comprehensive review of the wealth of research on the processes which determine the key quality attributes of apples, including texture and nutritional content.
The book addresses how these properties can be enhanced during the pre- and postharvest stages to ensure product quality and customer satisfaction, as well as the role of breeding programmes in identifying genes directly related to sensory quality characteristics. In its detailed exploration of the key quality attributes of apples, the book provides its readers with an insight into the science behind producing the 'perfect' product and have influential quality attributes are on consumer purchasing behaviours. Edited by an internationally-renowned researcher, Improving the quality of apples will be a standard reference for researchers in horticultural science, fruit growers, processors and retailers, as well as consumers, nutritionists and governmental and private sector agencies supporting the horticultural industry.
Fabrizio Costa is professor in the Centre for Agriculture, Food and Environment (C3A) at the University of Trento
From Introduction (pag. XVIII-XX)
This volume provides a comprehensive review of the wealth of research on the processes which determine the key quality attributes of apple. The chapters are split into two parts: Part 1 chapters discuss topics such an consumer perception of apple quality, understanding texture development, the nutritional and nutraceutical properties of apples and the development of antioxidant nutraceutical compounds. Chapters in Part 2 review breeding and crop management to optimise quality, focusing specifically on aspects such as fruit quality improvement, pre-harvest apple fruit development and quality management and finally postharvest management of apple quality.
Part 1 Quality attributes
The first chapter of the book focuses on consumer perception of apple quality.
Chapter 1 begins by providing an overview of the three key factors associated with consumer perception of apple quality: product-related, consumer-related and social environment-related factors. These points are then broken down. into three individual sections. The chapter identifies the main product-related aspects, focusing specifically on intrinsic and extrinsic characteristics of apple. It then goes on to describe the consumer-factors by categorising them into psychological and physiological/biological influences. Social environment-related features are broken down into situational, socio-cultural and economic influences. The chapter also reviews future research considerations on consumer perception of apple quality.
Chapter 2 draws attention to the texture development of apples. It begins by first focusing on the anatomy and physiology of fruit texture traits. This is then followed by an evaluation of fruit texture parameters. The chapter goes on to discuss the influence of growing conditions, the effects of storage on fruit texture as well as the impact fungal diseases can have on fruit texture. A section on genetic determination of texture is also provided, followed by a review of the association between texture and aroma, as well as an overview of selection/breeding achievements.
Chapter 3 discusses the nutritional and nutraceutical properties of apples by reviewing the latest scientific studies on the health benefits of apples. The chapter begins by discussing the phytochemical composition of apples, then goes on to identify the nutraceuticals in apple products, such as apple, puree, canned products, apple juice, apple sauces and other by-products such as pomace. A section on the role of apple nutraceutical compounds in promoting health and preventing disease is also included, focusing specifically on how consumption of these compounds has been correlated with positive outcomes for a variety of diseases, including cancer, diabetes, osteoporosis, cardiovascular disease, cognitive and lung disorders. The final chapter of Part 1 focuses on the development of antioxidant nutraceutical compounds in apples.
Chapter 4 begins by providing an overview of the nutritional composition of apples, drawing specific attention to macronutrients and micronutrients. The chapter moves on to discuss the various phytochemicals present in apples, providing individual sections on phenolic acids, flavonoids and antioxidants in essential oils. A section on the distribution of antioxidants in apples is also provided, which is followed by an overview of how oxidative damage to apples can impact their quality. Pre-harvest and postharvest changes in antioxidant content are also discussed and postharvest techniques preserving antioxidant content are reviewed. Finally, antioxidant bioavailability and the health benefits of antioxidants in apples are also discussed.Part 2 Breeding and crop management to optimise quality
Part 2 opens with a chapter that examines breeding for fruit quality improvement in apples.
Chapter 5 begins by providing an overview of apple quality trait phenotyping and its challenges, then examines how phenotypic selection can be used with and without DNA-based tools for apple quality breeding as well. The chapter also provides an overview of key fruit quality traits that are taken into consideration when breeding improved varieties, such as appearance, eating quality, and storability. A section on genome wide selection is also included in terms of how valuable a breeding approach it is in terms of apple quality traits.
Chapter 6 discusses advances in understanding pre-harvest apple fruit development. The chapter first provides an overview of key stages in apple fruit development, then goes on to review apple fruit growth models and precision orchard management. This is then followed by an overview of cell organization and intercellular spaces in apple fruit growth. The chapter also highlights key environmental factors that can affect fruit growth, such as light, temperature, altitude and latitude. Agronomic factors affecting fruit growth such as crop load and thinning, irrigation and tree architecture are also described. A section on fruit development and pre-harvest fruit sensory quality is also included.
The subject of Chapter 7 is advances in pre-harvest management of apple quality. The chapter begins by highlighting key internal and external quality attributes that are directly influenced once apples are harvested as a basis for the rest of the chapter's discussion for how these attributes can be improved during the pre-harvest stage. The chapter identifies emerging issues affecting pre-harvest management of apple quality. It focuses specifically on environmental factors such as light and temperature, then highlights the importance of orchard management practices in improving apple quality. The final chapter of the book discusses postharvest management of apple quality.
Chapter 8 begins by identifying the key pre-storage factors that can influence apple quality during the postharvest period, such as pre-cooling, then examine how edible coatings can influence the nutritional and physicochemical properties of apple. Storage factors that affect apple quality are also described, specifically the use of plant growth regulators, ethylene and the various storage environments that can be used to maintain/improve apple quality. Other quality management technologies are also described, specifically the use of ozone, photocatalytic oxidation, cold plasma and the use of ultraviolet-C radiation and ultrasound technology. A section on potential postharvest disorders is also provided, which is then followed by an overview of the importance of using the right packaging and transportation methods in apple quality maintenance.
Courtesy by Burleigh Dodds Science Publishing.