Celso Luiz Moretti

Hortaliças como alimentos funcionais

Although a very old concept, the relationship between food and health has never been as close as it is today. Diets rich in fat, salt, and sugar and poor in complex carbohydrates, vitamins, and minerals in association with a more sedentary lifestyle, are responsible for an increase in diet-related diseases such as obesity, diabetes, cardiovascular problems, hypertension, osteoporosis, and cancer. It is believed that the ingestion of fruits and vegetables helps in the prevention of these diseases. Vegetables are an important component of the diet, usually in association with protein- and starch-rich foods. They are responsible not only for adding variety of color and texture to meals, but also for providing important nutrients. Vegetables are low fat and low calorie foods, with relatively small amounts of protein, but they are rich in carbohydrates and fibers and add significant amounts of micronutrients to the human diet. They are also a source of functional substances, which might benefit one or more physiological functions in the body, besides adequate nutritional effects. Functional elements might play a role in improving health and well-being, as well as reducing the risk of the onset of diet-related diseases. The development of vegetable cultivars with greater amounts of these substances is one of the main goals of modern breeding programs. Many of these programs, working on different vegetables, are currently underway in Brazil and other countries, aiming to improve the amount and variety of carotenoids present in the diet. In the present paper, the main aspects of vegetable crops as functional foods are discussed. The most important achievements of tomato and carrot breeding programs in Brazil aiming to improve the amount and types of functional compounds are also presented.

1-Methylcyclopropene delays tomato fruit ripening

Tomato (Lycopersicon esculentum Mill.) fruits, cv. Santa Clara, were harvested at the breaker stage from commercial fields in Brazlândia, Brazil, to investigate the ability of 1-methylcyclopropene (1-MCP) to retard tomato fruit ripening. Fruit without external blemishes were graded for size (diameter = 80±5 mm) and mass (m = 130±10 g), placed inside hermetically sealed boxes, and 1-MCP was applied for 12 hours (T = 22±1°C; RH = 80-85%) at four different concentrations: 0 (control), 250, 500 and 1000 mL.L-1. Fruits were held at ambient conditions (T = 23±2°C; RH 80-85%) for 2 days and then stored inside a cold room (T = 20±1°C; RH = 85-95%). Every 3 days, during a 15-day period, fruits were analyzed for firmness, total soluble solids, titratable acidity, external color, and total carotenoids. Firmness of fruit treated with 1000 mL.L-1 was about 88% higher than control fruits after 17 days. The a*/b* ratio, an indicator of skin color, for fruit treated with 1000 mL.L-1 of 1-MCP was 38% lower than control fruits at the end of the storage period. Treatments with higher concentrations of 1-MCP delayed total carotenoids synthesis and color development. Control fruits stored for 17 days had about 190% more total carotenoids than fruits treated with 1000 mL.L-1 of 1-MCP. Postharvest application of 1-MCP was an efficient method to delay tomato fruit ripening. As 1-MCP concentration increased, ripening was further delayed. Tomatoes treated with 250, 500, and 1000 mL.L-1 of 1-MCP were delayed by 8 to 11, 11 to 13 and 15 to 17 days, respectively.

Aspectos fisiológicos e microbiológicos de beterrabas minimamente processadas

The aim of this work was to evaluate physiological and microbiological aspects of fresh cut beet roots. Respiratory activity and ethylene evolution were evaluated during four hours after processing and during the storage period of ten days at 5 o C. Microbiological analysis was carried out right after processing and after ten days of storage. Intact roots showed the lower respiratory activity (5 mL CO 2 kg -1 h -1 ), whereas shredded and peeled beet roots presented a respiration rate of 30 mL CO 2 kg -1 h -1 four hours after processing. Fresh cut beet roots showed a peak during the second storage day (80 mL CO 2 kg -1 h -1 ), reducing to 30 mL CO2 kg -1 h -1 at the fourth day. No ethylene evolution was detected in intact and peeled beet roots whereas in the fresh cut material it was observed in the first hours after processing, reaching 0.90 µL kg -1 h -1 . Few variations were observed during the four-hour period after processing and during the refrigerated storage. Psychotrophic bacteria and total coliforms counts were within acceptable limits, and no Salmonella or fecal coliforms were detected.

Production, quality and water use efficiency of processing tomato as affected by the final irrigation timing

O estudo foi realizado nas condicoes de Cerrado do Brasil, durante o periodo seco de 2000, para avaliar o efeito da epoca de paralisacao das irrigacoes na producao, qualidade de frutos e uso de agua do tomateiro para processamento. Os tratamentos corresponderam a quatorze epocas de paralisacao, espacadas a cada 7 dias entre o florescimento e a colheita. A maior produtividade de frutos comercializaveis foi obtida quando as irrigacoes foram suspensas 21 dias antes da colheita (10% dos frutos maduros), enquanto que o maior rendimento de polpa foi alcancado quando as irrigacoes foram finalizadas 34 dias antes da colheita (20% de plantas com pelo menos um fruto maduro). O teor de solidos soluveis totais foi reduzido linearmente a taxa de 0,34 oBrix para cada 10 dias a mais com irrigacao. A maior eficiencia do uso de agua pelo tomateiro foi obtida quando as irrigacoes foram paralisadas entre 37 e 45 dias apos o florescimento, respectivamente para producao de frutos e de polpa.

Conservação de melão rendilhado minimamente processado sob atmosfera modificada ativa

Net melons cv. Bonus II were minimally processed as cubes, wrapped in several packaging materials with injection of the gaseous mixture (5% O2 + 20% CO2 + 75% N2) and stored at 3oC for 12 days. The packaging materials were: BB-200: Cryovac multlayer film 65mm; PBC: Probag Conservax polyolephinic film 64µm; PP: polypropylene film 52µm. Polystyrene trays were used as control with perforated cover. Gaseous composition inside of the packaging, microbiological, sensorial and physical-chemical characteristics were determined each 3 days. The gas permeability was determined for each film. BB-200 packaging promoted CO2 accumulation until 24% and O2 reduction until 0,4%. Inside PBC packaging the O2 concentration stabilized at 8% and CO2 about 4%, while inside PP packaging the gaseous concentration stabilized near 13% for O2 and 6% for CO2. In a general sense, physical-chemical and sensorial characteristics were not influenced by the treatments. The modified atmosphere packaging was efficient for the microorganism control. The melon without modified atmosphere packaging showed levels over 105 NMP/g, of mesophilics bacteria, wich pathogenic microorganisms risks and/or deteriorative microorganisms, after 9th storage day.

Efeito do momento de sanitização sobre atributos fisico-químicos e microbiológicos de beterrabas minimamente processadas

Early Wonder beet roots were minimally processed and submitted to sanitization treatments: control (no sanitization); sanitization after cutting (standard); sanitization before peeling and after cutting; sanitization only after peeling; sanitization before and after peeling; sanitization before and after peeling and after cut. After the treatments, the product was placed on trays wrapped in PVC film and stored at 5±1°C and 85±5% RH for 10 days. Physicochemical and microbiological analyses were conducted during refrigerated storage. Fecal coliforms and Salmonella were not detected in beet roots that underwent sanitization. Total coliforms and psychotropic bacteria counts, as well as betacyanin and betaxanthin amounts were higher in non-sanitized beet roots. There was a decrease in pigment amounts during storage. Post-peeling sanitization is the most suitable for quality maintenance, as it reduces pigment loss, ensures good food safety standards and avoids chlorine waste.

Modified Atmosphere Packaging for Perishable Plant Products

Packaging perishable plant products is one of the more important steps in the long and complicated journey from grower to consumer. Millions of different types of packages are used for produce around the world and the number continues to increase as the industry introduces new packaging materials and concepts. Packing and packaging materials contribute a significant cost to the produce industry; therefore it is important that packers, shippers, buyers, and consumers have a clear understanding of the wide range of packaging options available (Boyette et al., 1996). This fact chapter describes some of the many types of packaging materials, including their functions, uses, and limitations. Within packaging plastics for plant products, if commodity and film permeability characteristics are properly matched, an appropriate atmosphere can evolve passively through consumption of O2 and production of CO2 during respiration (Mir & Beaudry, 2002). Gas exchange and respiration rate through the package material are the processes involved in creating a modified atmosphere inside a package that will extend shelf life of fresh fruits and vegetables. The major methods for measuring respiration rates, along with their advantages and limitations are discussed. Modified atmosphere technologies have great potential in a wide range of applications in plant products. The usual methods of respiration rate determination can be the static system, the flowing system and the permeable system (Fonseca et al., 2002). The respiration rate of fresh produce can be expressed as O2 consumption rate and/or CO2 production rate. Factors affecting the respiration rate and respiratory quotient are outlined, stressing the importance of temperature, O2 and CO2 concentrations, and storage time (Kader et al., 1989). Modified atmosphere packaging should always be considered as a supplement to proper temperature and relative humidity management. The differences between beneficial and harmful concentrations of oxygen and carbon dioxide for each kind of produce are relatively small, so great care must be taken when using these technologies. Temperature has been identified as the most important external factor influencing respiration (Tano et al., 2007). The internal factors affecting respiration are the type and maturity stage of the commodity. Vegetables include a great diversity of plant organs such as fruits, roots, tubers, seeds, bulbs, sprouts, leaves and stems that have different metabolic activities and consequently different respiration rates. Different varieties of the same product exhibit specific respiration rates. The success of modified atmosphere packaging greatly depends on the accuracy of the predictive respiration rate (Kader, 2002). The main objective of this chapter is to present different packaging materials using modified atmosphere for perishable plant products, focusing

Estabilidade de repolho minimamente processado sob diferentes sistemas de embalagem

Stability of fresh-cut cabbage packed in low density polyethylene under active modified atmosphere and in expanded polyestyrene trays wrapped with PVC was evaluated. The fresh-cut product was stored for 16 days in a cold room at 5 ± 1 °C and 95 ± 5% RH and in a refrigerated display case similar to those found in grocery stores. The following variables were analyzed: content of oxygen and carbon dioxide inside the package headspace; browning, luminosity, polyphenoloxidase and peroxidase activities, pH, titratable acidity; soluble solids, fresh mass loss, and ascorbic acid content. The stability of fresh-cut cabbage was higher at the temperature of 5 °C compared to those stored in the refrigerated displays. The active modified atmosphere was not effective in extending the shelf life of fresh-cut cabbage compared to other treatments. LDPE packaging was more adequate for fresh-cut cabbage storage. However, PVC wrapping also presented satisfactory effects.

Avaliação técnica e econômica do espaçamento de gotejadores em tomateiro para processamento cultivado em fileiras simples e duplas

Technical and economic evaluation of drip spacing for processing tomatoes under single- and double-row planting systems Processing tomatoes crop response to drip spacing (10 cm and 30 cm) and planting systems (single- and double-row planting, and a lone drip line) was evaluated in Brasilia, DF, Brazil. A control treatment with single-row planting system was sprinkle irrigated. Marketable yield for 10-cm drip spacing was 10% higher than for 30 cm. Yield from drip single-row treatments was 9% higher than from double-row ones. Yield from sprinkle irrigated plots did not differ from the 30-cm drip spacing and double-row treatment, but was at least 15% lower than from other treatments. Rotten fruit rates were not affected by drip spacing factor, but were higher in doublerow treatments. In the control treatment, rotten fruit occurrence was at least 68% higher than in the drip treatments. Greater economic efficiency was obtained for the 10-cm drip spacing and single row system treatment (12.7%), followed by drip spacing of 10 cm and double-row planting (7.5%). The revenue rates for those treatments were 1.42 and 1.39, respectively.

Qualidade de melão minimamente processado armazenado em atmosfera modificada passiva

ABSTRACT Quality of fresh cut melons stored under passive modifiedatmosphere Fruits of net melon cv. Bonus II were minimally processed ascubes, wrapped in several plastic materials and stored at 3oC for 9days. The following materials were used for packaging: AFG: DuPontpolyolephinic film 15µm; HP: DuPont polyolephinic film 15µm,PD-900: Cryovac polyolephinic film 58µm, PEBD: low densitypolyethylene film 87µm; PP: polypropylene film 52µm; BB-200:Cryovac multilayer film 65 µm; PET: rigid polyethylene terephtalattray. The gas permeability of each film was determined. The gascomposition within the packages was evaluated every day during 8days and the physico-chemical and sensorial characteristics wereevaluated on the 9 th day. The melon respiration rate was determinedbefore and after processing. The packaging systems did not promoteeffective atmosphere modification, except for the PET tray whichpromoted, after the 6 th day, an equilibrium atmosphere of 12% O 2 and 7% CO 2. Physical-chemical characteristics of the processedmelons were maintained in all treatments during storage, whereassensorial characteristics were kept only for the melons in the PETtray. Passive atmosphere modification was not effective for freshcut melons stored at 3oC. Probably due to the low respiration rate atthis temperature associated with the high relationship betweenpermeation area of the packages and melon mass.