73586 - Fruit Processing

Learning outcomes

The course provides specific knowledge to identify and understand the key processing steps occurring in fruit processing. In particular, at the end of the course, the students will be able to: 1) describe the main steps required to produce processed fruits (such as cloud/clear juices, nectars, puree, jams, jellies and marmalades, ciders and distillates) and link them with the main unit operations characterizing hot and cold technologies used in fruit processing, including washing, peeling, enzyme treatments, pasteurization and sterilization. 2) evaluate the mass and energy balance of the main fruit processes. 3) understand the main chemical and microbial changes occurring to processed fruits, such as pectin jellification, yeast fermentation, enzymatic browning, juice sedimentation and the microbial thermal death.

Course contents

NB: This teaching activity takes place at the University of Bolzano and it is NOT available for Erasmus Incoming students.

The course is designed to provide graduate students with an overview of the main processing steps used during the transformation of fruits, emphasizing the chemical, physical and biological changes occurring during processing. Specific attention will be given to the production of fresh cut fruits, fruit juices, jams, jellies and marmalades and dried fruits.

In details, the course will cover the following specific topics:

1. Main unit operations in fruit processing;

2. Quality, stability and shelf life of processed fruits;

3. Thermal processing of fruits and their effect on quality, stability and safety

4. Production systems of fruit juices, fruit puree, concentrated juices and jellies

5. Use of enzymes, pectins and antioxidants

Readings/Bibliography

The content of the course is based on the following bibliography:

• Slides presented during the lectures.

• Mircea Enachescu Dauthy, in: Fruit and vegetable processing, FAO AGRICULTURAL SERVICES BULLETIN No.119, freely available online at http://www.fao.org/docrep/V5030E/V5030E00.htm

Furthermore, for a deeper understanding of the topic presented during the course, it is recommended the reading of the following book:

• Diane M. Barrett, Laszlo Somogyi, Hosahalli S. Ramaswamy in: Processing Fruits: Science and Technology, Second Edition, CRC Press.

Teaching methods

This course consists of 18 h of frontal lectures and 12 h of practical exercises.

Frontal lectures will be hold by the Professor in the form of digital slides and videos.

Exercises will consist on the solution of practical problems with the use of a spreadsheet (MS Excel).

Lab activities will include the measurement of the main quality variables and the use of enzymes and pectins.

Assessment methods

Coursework will be a final written exam. The written exam will consist of open/closed questions (like Quiz) dealing with:

- Description of the main unit operations discussed during the course

- Description of fruit processing procedures (i.e. fresh cut fruits, fruit juices, jams)

- Description of chemical, physical and biological properties of fruits, including microbial pathogens, enzymes, antioxidants and pectins.

Teaching tools

Power Point presentations and Excel files used during the class will be provided by the Professor.

Office hours

See the website of Matteo Mario Scampicchio