Mohammed Wasim Siddiqui

Washing, Peeling and Cutting of Fresh-Cut Fruits and Vegetables

The consumptions of fresh fruits and vegetables are directly linked to reduced risk of chronic diseases and to enhance resistance against diseases (Van Duyn and Pivonka 2000). In addition to the pleasure of eating fruits and vegetables, these provide various phytochemicals and antioxidants (Kalt 2005), phytoestrogens, and anti-inflammatory agents (Vincent et al. 2010) and other protective compounds (Kaur and Kapoor 2001; Slavin and Lloyd 2012). These aspects of health benefits led to the tremendous increased market for fresh cut and minimally processed fruits and vegetables. Fresh-cut products are preferred over processed one because consumers are now aware of the commonly nutritional losses, desired sensory attributes such as color and flavor and increased demand for ‘natural-like’ attributes (Kader 2002). The fruits and vegetables constitute a suitable meal for satisfying today’s lifestyles, because these need minimal preparation and provide a great meals with varieties of nutrients, vitamins and minerals (Froder et al. 2007).

Postharvest biology and technology of sapota: a concise review

Sapota is cultivated in many countries of tropical and subtropical climate. It is delicious, nutritive, and commercially grown mainly for fresh consumption. Postharvest life of sapota is very short due to its highly perishable nature and other many reasons such as quick ripening, faster senescence, rapid loss of moisture, microbial spoilage, and fruit sensitivity to cold storage. To maintain and/or increase the shelf life of sapota, proper postharvest management is required. Unfortunately, very little work has been done so far, with limited success, leaving scarce literature published on postharvest management technologies of sapota. Different pre and postharvest treatments to reduce metabolic activity and quality loss have been suggested. Moreover, proper storage temperature and packaging may be used to increase the shelf life of fruits. This review explores the postharvest technologies adopted to enhance the shelf life of sapota during storage and distribution channel.

Minimally Processed Foods: Overview

Over the past decades, consumers want fresh like foods with their natural nutritive values and sensory attributes, such as flavor, odor, texture and taste (Huxley et al. 2004). Fresh fruits and vegetables are the good examples of convenient foods. This growing consumers’ demandof minimally processed foods with no or lesser synthetic additives pose challenges to food technologists. In addition, demand of functional foods to prevent or control of diseases are growing (Monteiro et al. 2011). All these demands force to develop safe foods with minimal processing techniques (Gilbert 2000). This is not a simple task to produce safe minimally processed foods with desired shelf-life.

Factors Affecting Postharvest Quality of Fresh Fruits

From many studies and field observations over the past 40 years, it has been reported that 40–50 % of horticultural crops produced in developing countries are lost before they can be consumed, mainly because of high rates of bruising, water loss, and subsequent decay during postharvest handling (Kitinoja 2002; Ray and Ravi 2005). Nutritional loss (loss of vitamins, antioxidant, and health-promoting substances) or decreased market value is another important loss that occurs in fresh produce. Quality of fresh produce is governed by many factors. The combined effect of all decides the rate of deterioration and spoilage (Siddiqui et al. 2014; Barman et al. 2015; Nayyer et al. 2014). These factors, if not controlled properly, lead to postharvest losses on large scale. According to Kader (2002), approximately one third of all fresh fruits and vegetables are lost before it reaches to the consumers. Another estimate suggests that about 30–40 % of total fruits and vegetables production is lost in between harvest and final consumption (Salami et al. 2010). Quality deterioration starts as soon as it is harvested and continued till consumed or finally spoiled if not consumed or preserved. The success or failure of any business plan related to fresh produce is totally dependent on the management of factors affecting the quality. This is obvious because fresh fruits and vegetables are living in nature, complete remaining life cycle after harvest, and then naturally spoil. This character puts fresh fruits and vegetables in the category of highly perishable commodities. Developed countries are in a very good position as they have developed good systems of postharvest management and infrastructure for quality maintenance. At the same time, developing countries are far behind in the same business, i.e., lacking in good postharvest practices and supporting infrastructure for quality maintenance. The outcome of this lacuna is considerably very high in developing countries. This is one of the reasons that postharvest losses in fresh fruits and vegetables are estimated about 5–35 % in developed countries and 20–50 % in developing countries (Kader 2002). In another report, it is reported that 40–50 % of horticultural crops produced in developing countries are lost before they can be consumed, mainly because of high rates of bruising, water loss, and subsequent decay during postharvest handling (Kitinoja 2002; Ray and Ravi 2005). In both fruits and vegetables, many more additional changes take place after harvesting. Changes are noticed more in climacteric fruits and vegetables than non-climacteric. Some changes are desirable from consumer point of view, but most of them are undesirable. Development of sweetness, color, and flavor are best examples of desirable changes. These desirable changes persist for few days only. This is the stage liked by almost all consumers. At the same time, shelf life decreases and many undesirable changes take place such as water loss, shrinkage, shriveling, cell wall degradation, softening, physiological disorder, overripening, disease attack, rotting, and many more. All these changes, if not governed, ultimately affect the quality. These changes in fresh produce cannot be stopped, but these can be slowed down within certain limits if factors responsible for such deterioration can be minimized. This is important because it increases shelf life and marketing period of fresh produce and maintains their quality during postharvest handling. There are few proven methods and technologies used to slow down the undesirable changes for extended availability such as control of optimum low temperature and humidity during storage, suitable packaging, transportation, and maintenance of storage atmosphere.

Technologies in Fresh-Cut Fruit and Vegetables

Fresh-cut fruit and vegetables (FCFV) consumption has increased significantly in recent years. Because of the changes in consumer lifestyles, there is an increased demand of fresh-cut foods, which are nutritious, functional, safe, attractive, and ready-to-eat. The consumers perceive these products as the most appealing, considering their attributes, such as fresh-like appearance, taste, flavor, and convenience. However, FCFV products are very sensitive to spoilage and microbial contamination due to the processes used for its preparations (e.g. peeling, cutting, and grating). These processes caused mechanical injury to the plant tissues and promoted biochemical changes, microbial degradation, and the consequence is the loss of quality. However, some alternatives are proposed in order to avoid biochemical problems due to mechanical injury (e.g. immersion therapy). Furthermore, several technologies are used to preserve the quality of fresh-cut produce, for example, ultraviolet light, controlled and modified atmospheres, edible coatings, heat treatments, and use of natural compounds.

When Color Really Matters: Horticultural Performance and Functional Quality of High-Lycopene Tomatoes

ABSTRACT Introgression of spontaneous or induced mutations has been used to increase the levels and diversify the profile of antioxidants in many fruits including tomato. The high-pigment (hp) and old-gold (og) alleles exemplify this approach as attractive genetic resources suitable to inbred elite high-lycopene (HLY) tomato lines with improved color and nutritional attributes. Although several studies have been published on HLY tomatoes, a systematic analysis of the information on their agronomic performances, processing features, and functional quality is lacking, leaving room for the assumption of their poor competitiveness with conventional tomato cultivars and limiting their agricultural diffusion. Therefore, the aim of this study is to critically review the most important agronomic, horticultural, and functional traits of HLY tomatoes, as well as the advances in some emerging (pre)industrial applications. Field experiments performed in different countries showed that most available HLY lines are productive, vigorous, with excellent foliage cover and with morphologically acceptable fruit. Tomato yield of HLY genotypes ranged from ∼30 to ∼178 t/ha exceeding, in some trials, that of highly productive cultivars. Red-ripe fruits of most HLY lines showed commercially suitable soluble solids and titratable acidity, in addition to increased levels of lycopene (up to 440 mg/kg fw) and other bioactive phytochemicals (mainly flavonoids and vitamin C) compared to their near isogenic conventional counterparts. Innovative (pre)industrial uses of HLY tomato include the following: (1) production of HLY sauces, juices, and powders; (2) supercritical-CO2 extraction of lycopene containing oleoresins; and (3) preparation of lycopene rich micro- and nano-carriers with improved stability and specific tissue delivery. In turn, the use of these innovative high-quality ingredients in the formulation of lycopene fortified foods, cosmetic products, nutraceuticals, and pharmaceuticals has been proposed as the basis of a novel highly profitable tomato product chain.

Advances in postharvest technologies to extend the storage life of minimally processed fruits and vegetables

ABSTRACT Minimally processed fresh produce is one of the fastest growing segments of the food industry due to consumer demand for fresh, healthy, and convenient foods. However, mechanical operations of cutting and peeling induce the liberation of cellular contents at the site of wounding that can promote the growth of pathogenic and spoilage microorganisms. In addition, rates of tissue senescence can be enhanced resulting in reduced storage life of fresh-cut fruits and vegetables. Chlorine has been widely adopted in the disinfection and washing procedures of fresh-cut produce due to its low cost and efficacy against a broad spectrum of microorganisms. Continuous replenishment of chlorine in high organic wash water can promote the formation of carcinogenic compounds such as trihalomethanes, which threaten human and environmental health. Alternative green and innovative chemical and physical postharvest treatments such as ozone, electrolyzed water, hydrogen peroxide, ultraviolet radiation, high pressure processing, and ultrasound can achieve similar reduction of microorganisms as chlorine without the production of harmful compounds or compromising the quality of fresh-cut produce.

Chitosan: properties and roles in postharvest quality preservation of horticultural crops

Chitosan is a biopolymer, which is obtained from the discarded by-products residual in edible crustaceans such as shrimps and crabs. The chitosan polymer exhibits a wide applicability in various arenas, which range from agriculture, medicine, tissue and bone engineering, the food sector, cosmetics, textiles, pharmaceutical nanostructure materials, biotechnology, the paper industry, and even wastewater treatment. The physical properties of the chitosan polymer exert significant influence on its biological properties. The application of chitosan biopolymer as an edible coating on horticultural commodities has revealed immense potential to maintain the quality as well as extend postharvest life of several fruits such as litchi, longan, papaya, peach, mango, table grapes, strawberries, and sweet cherries among many others. The chitosan polymer is also used in the agricultural fields for its antimicrobial activities to reduce the losses due to decay and diseases. Additionally, chitosan biopolymer can increase yield, is natural, edible, and biodegradable without having any adverse influences such as allergenic, mutagenic, or carcinogenic activities. The chitosan polymer has natural antimicrobial, environment friendly, biocompatible, biodegradable, and film-forming properties, and is nontoxic to mammals. Thus it exhibits the potential to be used for maintaining the quality, safety, and enhancement of the postharvest life of agricultural and horticultural commodities and minimally processed food products.

Training and Pruning for Improved Postharvest Fruit Quality

The postharvest fruit quality depends on the maintenance and health of the fruit trees in orchard. The various preharvest operations, such as irrigation, training, pruning, fertilizer application, spray of various plant growth regulators, insecticides, and pesticides are the deciding factors that regulate the ultimate quality of the fruits during postharvest handling and storage. Training is done to achieve the desirable shape and form of the trees while pruning is mainly done to obtain quality fruit production. Training and pruning operations are essential in perennial fruit crops to optimize the light distribution, minimize the insect pest and diseases attack and for production of fruits of optimum quality. Training and pruning operations play a significant role in obtaining regular and prolific quality fruit production. The size, color, nutritional quality, and postharvest shelf life of fruits are all significantly affected by the training and pruning operations done during the preharvest stages in orchard. This chapter provides an insight into the basics of training and pruning systems and how they affect the postharvest fruit quality.

Preharvest Biofortification of Horticultural Crops

Micronutrient malnutrition or hidden hunger is an alarming public health issue in developing countries, affects more than half of the world’s population, and causes enormous loss in quality and quantity of mankind. Among the malnourished population, vitamin A, iron, zinc, iodine, and selenium deficiency are predominant. Modern plant breeding has been focused primarily toward achieving high agronomic yields rather than nutritional quality, and conventional efforts like supplementation, diet diversification, and industrial fortification cannot mitigate the situation. Biofortification is a practice of nutrient fortification in food plants involving modern breeding, transgenic approaches, improved agronomy, and microbiological interventions toward changing genetic architecture, improving micronutrient uptake, and proper distribution in edible tissues to safe levels, reduction in antinutrients in food staples for promoting bioavailability of nutrients thereby becoming a sustainable and long-term strategy to address negative impacts of vitamin and nutrient deficiencies. Considering the nutritional impact of horticultural crops, biofortification program have been carried out in potato, cassava, sweet potato, beans, cow pea, bananas through the joint effort of national and international organizations. Several conventional and transgenic varieties have been released and disseminated to the farming communities, and additional varieties are in the pipeline. However, the effectiveness of the biofortification program essentially relies on the farmers’ and consumers’ acceptance and future policy interventions. Therefore, strategic research and appropriate policy can lead to biofortification’s grand success in the near future.