Processed Apple Products

The objective of this book is to organize and document the technical, analytical, and practical aspects of present-day apple processing. No collected works have been published on processed apple products for more than thirty years. During that time many changes have taken place in the apple-processing industry. There are fewer but larger plants processing apples from larger geographical areas because of advances in transportation and storage of fruit. In addition sophisti­ cated technical advances in the processing and packaging of apple products have also occurred. This volume is designed to serve primarily as a reference book for those interested and involved in the processed apple industry. An attempt has been made to provide a central source of historical, currently practical, and theoretical information on apple processing. References have been cited to give credibility and assist those who may wish to read further on a particular subject. If this book success­ fully summarizes present knowledge for readers and assists in the continued improvement of commercial fruit processing, I will be pleased. I would like to thank the many people in the apple industry who have requested information and encouraged the writing of this book. The late Dr. Robert M. Smock, Professor Emeritus, Cornell Univer­ sity, and coauthor of Apples and Apple Products, originally published in 1950, gave his blessings and encouragement to this undertaking.

1. Apple Cultivars for Processing.- Apple Production.- Apple Cultivars.- Utilization of Apples in the United States.- Processing-Apple Cultivars and Growing Regions.- Processing Characteristics.- Agronomic Characteristics.- 2. Harvesting, Storing, and Handling Processing Apples.- Development and Ripening of Apples.- Disorders and Defects of Apples.- Harvesting Apples.- Storing Apples.- Poststorage Handling of Apples.- 3. Apple Pressing and Juice Extraction.- Types of Apple Juice.- Selection of Fruit.- Washing and Inspecting Fruit.- Milling Apples.- Pressing and Extracting Apples.- Quality and Yield of Apple Juice.- 4. Clarification of Apple Juice.- Substrates Contributing to Turbidity.- Pectolytic Enzymes.- Use of Pectinases for Juice Clarification.- Defects in Clarified Juice.- Nonenzymatic Clarification.- 5. Causes and Prevention of Turbidity in Apple Juice.- Mechanism of Haze Formation.- Types of Hazes.- Testing Procedures.- Fining Agents and Their Preparation.- Fining Procedures.- Ultrafiltration.- Recovery of Stored Juice.- 6. Filtration of Apple Juice.- Filter Aids.- Preparing Juice for Filtration.- Pressure Filters.- Vacuum Filters.- Membrane Filters (Ultrafiltration).- Handling Apple Juice After Processing.- Design of Production Systems.- 7. Concentration of Apple Juice.- Concentration by Evaporation.- Concentration by Reverse Osmosis.- Freeze Concentration.- Economics of Concentration Processes.- 8. Apple Cider.- Sweet Cider.- Fermented (Hard) Cider.- 9. Aseptic Processing and Packaging of Apple Juice.- Overview and Comparison with Conventional Processing.- Product Sterilization.- Preparation of Aseptic Packages.- Quality Assurance.- Design of APP Systems.- Federal Regulations.- 10. Applesauce and Other Canned Apple Products.- Cultiver Selection.- Raw-Product Condition, Grades, and Tests.- Initial Unit Operations in Apple Canning.- Applesauce Processing.- Apple Slice Processing.- Baked and Glazed Apple Processing.- Quality Control.- Robotics in Food-Processing Operations.- 11. Refrigerated, Frozen, and Dehydrofrozen Apples.- Cultivar Selection.- Fruit Condition.- Overview of Unit Operations.- Antibrowning Treatments.- Dehydrofreezing of Apple Slices.- 12. Dried Apple Products.- Definitions.- Cultivar Selection.- Advantages of Dried Foods.- Predrying Operations.- Factors Affecting Drying.- Drying Equipment and Methods.- Postdrying Operations.- 13. Cider Vinegar.- Production, Terminology, and Uses.- Chemical and Microbiological Background.- Raw Material and Alcoholic Fermentation.- Acetification.- Clarification and Packaging.- Composition of Cider Vinegar.- Specifications for Cider Vinegar.- Defects.- Color.- 14. Composition and Nutritive Value of Apple Products.- Overall Composition.- Carbohydrates.- Fiber.- Vitamins.- Pectin.- Amino Acids.- Minerals.- Organic Acids.- 15. Flavor Components and Quality Attributes.- Sensory Physiology.- Flavor Chemistry.- Sensory Attributes.- Sensory Properties of Apple Products.- Future Uses of Apple Functional Components.- 16. Microbiology and Preservation.- Types of Organisms.- Measurement of Microbiological Quality.- Preservation Methods.- 17. Treatment and Utilization of Apple-Processing Wastes.- Apple-Processing Wastewaters.- Apple Pomace.- Appendix A: Analytical Methods.- Determination of Sulfur Dioxide in Apple Products.- Method for Checking Bisulfite Bath.- Peroxidase Test for Adequacy of Blanching.- Appendix B: Conversion Tables.- Table B-1. Metric Units and U.S. Equivalents for Measures of Weight, Length, Area, and Capacity.- Table B-2. Dry Measure and Liquid Measure Equivalents.- Table B-3. Temperature Conversion Formulas.- Table B-4. General Conversion Factors.- Table B-5. Conversion of Apple Sizes to Various Units.- Table B-6. Conversion Between Moisture Content on Wet-Weight Basis (W.W.B.) and Bone-Dry Basis (B.D.B.).- Appendix C: Properties of Sucrose, Sodium Chloride, and Alcohol Solutions.- Table C-1. Relationship Between °Brix, Specific Gravity, Solids Content, and Water Content of Sucrose (Cane Sugar) Solutions.- Table C-2. Relationship Between Specific Gravity and Concentration of Aqueous Alcohol Solutions.- Table C-3. Properties of Sodium Chloride Brine at 60 °F.- Appendix D: Miscellaneous Tables and Charts.- Table D-1. Corrections to Refractometer Determination of Sucrose Concentration When Readings Made at Temperatures Other Than 20 °C.- Table D-2. Amounts of Sulfur Dioxide Required per 1,000 Gallons of Juice or Cider.- Table D-3. Approximate Heat Evolution Rates of Fresh Apples at Different Storage Temperatures.- Fig. D-1. Filtration Porosity Comparisons.- Fig. D-2. Psychometric Chart—Properties of Air and Vapor Mixtures from 32 to 60 °F.- Appendix E: Information on USDA Grade Standards.- Publications.- Visual Aids.- Appendix F: Information on Standards of Identity, Quantity, and Fill.- Appendix G: Tables for Hard Cider and Apple Wine.- Table G-1. Approximate Dilution of Extract in Wines from the Addition of High-Proof Brandy.- Table G-2. Winery Hose Data.- Table G-3. Flow Estimation from a Horizontal 2-Inch Hose.- Table G-4. Legal U.S. Wine Bottle Sizes.- Table G-5. Traditional U.S. Wine Bottle Sizes.- Table G-6. Correction of Wine Spirits Volume to 60 °F.- Table G-7. Estimation of Partially Filled Horizontal Tanks.- Table G-8. Wine Tank Capacities.- Table G-9. Vat Capacities.- Table G-10. Example of English Measure Tank Chart for Straight-Sided Horizontal Tank.- Table G-11. Example of Metric Measure Tank Chart for Straight-Sided Vertical Tank.