Development of Processing Methods to Increase the Quality and Shelf-Life of Fruit Juices and Beverages

Non-Technical Summary: Even though fruit juice sales in the US accounted for 6.4 billion dollars in 2006, their consumption has been in decline for the last five years, down 19% since 2002. Consumers perceive fruit juices as high calorie, high sugar foods, and recent surveys show that 29% of respondents cite high calorie content as the main reason for not buying juices. Juices also face strong competition from sports drinks and flavored waters, which are developed for specific markets. There are concerns over child obesity, with the recommendation from pediatricians for kids to eat more fruits and vegetables instead of juices. The American Association of Pediatricians states that half of the recommended daily allowance of fruits/vegetables currently comes from juice, as many children will not eat fruit. As it is difficult for consumers to increase their fruit intake based solely on fresh fruit, there is a need to offer healthy, convenient, high quality fruit beverages that provide the benefits consumers require. The development of refrigerated and shelf-stable juices with better nutritional quality, closer to whole fruits, represents an important area of research to help not only consumers but farmers and processors that need to adjust their processing technologies to offer consumers juices with added health benefits and improved quality. In New York State, apples and grapes represent the major fruit crops, 20% and 98% of which are processed into beverages respectively. Other important NY fruits for beverage production include tart cherries and other berries. In order to maintain the viability of NY farms and processors, it is vital to develop and implement new technologies and formulations in juice production adequate to the size and type of processors currently in the State, and to incentive new businesses focused on high quality fruit beverages. This project will focus on developing food processing techniques that result in more nutritious juices and beverages, in new products and therefore new marketing opportunities for juices made from NY fruits. By meeting the needs of consumers, NY producers will have better positioning in the marketplace and more sustainable businesses, as new products and innovative processing will add value to NY fruit crops, extend the marketing season and enhance the economic viability of NY agriculture. <P> Approach: Objective 1: The work will be conducted in laboratories and in the Fruit and Vegetable Processing Pilot Plant located at the Department of Food Science and Technology, Cornell University. Fruit varieties of commercial importance to NY State will be studied to determine if there are significant differences that warrant individual processing methodologies. Fresh fruit will be processed into different types of juices such as clear (control), cloudy and pulpy, utilizing a variety of processing methodologies, equipment and packaging materials to assess best ways to extract and retain polyphenolic compounds. Storage studies (up to 6 months) will be conducted to assess conditions that best retain quality over the shelf-life of the juice. The quality of the juices will be evaluated by measuring physical, chemical, sensory attributes and microbial counts (for perishable products). Product acceptability and overall quality will be assessed by taste panels. Total aerobic plate counts and yeast and mold counts will be used to determine the efficacy of treatments and the length of shelf-life for refrigerated juices. All studies will be conducted in triplicates (at least duplicates for pilot plant trials) to allow for statistical analysis. Objective 2: Most procedures described in objective 1 will be followed, and additional factors will be studied to evaluate the best conditions to incorporate the maximum amount of dietary fiber (both soluble and insoluble) in the juices without compromising consumer acceptance. Size reduction and homogenization techniques will be tested to determine optimal parameters to produce a fiber enhanced clear, cloudy or pulpy juice. Additional measurements to be performed on fresh and processed samples include total dietary fiber, pectin content, viscosity and percent settled solids to attempt to correlate measurements with sensory attributes and acceptance results. Objective 3: New technologies and ingredients are being introduced every year that can impact production, quality and shelf-life of fruit juices and beverages. As consumers are more interested in natural, fresher, flavorful products, it is critical to study novel processes and formulations that permit the production of minimally processed beverages for the premium market. Refrigerated juices and beverages are part of this trend, relying on mild pasteurization, non-thermal processing, natural antimicrobials and specialized bottling/packaging to extend shelf-life. This work will include microbiological testing of the different products to assess the effectiveness of novel treatments on the destruction of pathogens and spoilage microorganisms. The different treatments that will be studied include: mild pasteurization regimes, UV processing, addition of functional ingredients to preserve specific juice quality factors, use of processing aids and natural preservatives, use of oxygen absorbers and specialized packaging. It is expected that the combination of several of these options will result in improved quality for refrigerated products and reduced thermal processing for shelf-stable beverages.