Fiber-Rich Food Processing Byproducts Enhance the Expansion of Cornstarch Extrudates

Expansion characteristics of cornstarch-based extrudates incorporating fiber-rich food processing byproducts was explored. Waxy and regular cornstarch were used as the base materials with apple pomace and sugarcane bagasse incorporated at two addition levels (0%, 15%, and 30% w/w). Extrusions were conducted at three different screw speeds (150, 200, and 250 rpm) with other parameters optimized and kept constant. Apple pomace inclusion resulted in higher initial expansion index (4.23 to 5.60) and higher stable expansion index (2.76 to 4.43), but also showed higher shrinkage (8.50% to 34.72%) than sugarcane bagasse extrudates at the same inclusion levels. Inclusion of apple pomace showed potential of producing extrudates with significantly higher expansion than cornstarch control, with relatively lower energy inputs. Extrusion methods used here have the potential to preserve the textural quality and nutritional value of the fiber-enriched extrudates, providing the base for healthier snack food items. Findings from this study can be extended to the other fiber-rich food processing byproducts, such as other fruit and vegetable pomace, cereal brans, and pulse hulls among other materials. This data will help the development of fiber-enriched extruded snacks that would have favorable consumer traits

Cooling and Freezing of Fruits and Fruit Products

The use of low temperatures is an important factor for maintaining postharvest quality of fruits and greatly influences the rate of deterioration. The objective of cooling is to prolong the commercial life of perishable products, by decreasing metabolic activity without causing chilling or freezing injuries, reduction of microbial growth and water loss of the product, between others. On the other side, freezing results in improved effects with respect to shelf life of fruits and availability throughout the year, however various undesirable changes occur due to ice formation.In the present chapter pre-cooling treatments and refrigerated storage of fruits are analyzed. The use of controlled and modified atmosphere storage, novel technologies (thermal treatments, UV-C irradiation, etc.), minimally processed fruits and the use of edible coatings are analyzed.With reference to fruit freezing the formation of ice in tissues (nucleation and crystal growth, intra and extracellular ice), initial freezing point, state diagrams, glass transition temperature, freezing rates and the different equipment used for freezing are described.The effect of freezing rate on fruit quality, physical and chemical modifications, nutritional properties and microbial stability of frozen fruit are discussed. Preparatory operations for freezing such as pre-treatments of fruits using sugar syrups, and dehydrofreezing are explained. Recommended packaging and industrial freezing methods, shelf-life of frozen fruits and new trends in freezing technology are also analyzedFil: Chaves, Alicia Raquel. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; ArgentinaFil: Zaritzky, Noemi Elisabet. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Investigación y Desarrollo en Criotecnología de Alimentos. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Investigación y Desarrollo en Criotecnología de Alimentos; Argentin