Table Olive Processing by International Olive Oil Council

Table olive production has a deep-rooted tradition in all the countries bordering the Mediterranean, from where it spread down through the centuries to other areas, mainly the American continent. However, until very recently, table olives were prepared according to non-industrial methods, something which is still the case in some places even today.

With the aim of improving this situation, several countries, including Spain, have taken considerable pains to research in depth into the scientific and technical foundations of these processes. Today, thanks to this research, table olives can be processed safely using proven technology.

The International Olive Oil Council has always been concerned with improving the quality of table olives. Proof of that interest lies in the international courses it has organised for technicians and producers from its member countries, which have been highly successful and have proved useful to the participants.

The purpose of this manual is therefore to make table olive technology expertise available to anyone interested in the subject, scientists, technicians and the general public alike. It is based on material gathered from the international courses that the Seville Fats and Oils Institute's Food Biotechnology Department has run at the request of the I.O.O.C. Subjects directly related to processing have been specially selected with the aim of creating a real production handbook.

While the manual is based on the investigation work of the research team and the technical experience of the Institute, the chapters that follow deliberately avoid the excessive use of scientific terms, thereby striving to make it accessible to a wider range of readers.


1 TYPES AND VARIETIES OF TABLE OLIVES 13   1.1. Introduction
1.2. Types of table olives
1.3. Trade preparations
1.4. Styles
1.5. Pack placement
1.6. Varieties used in Spain
1.7. Major table olive varieties grown world-wide

  2 PROCESSING OF GREEN OLIVES 29   2.1. Harvesting and transportation
2.2. Lye treatment

  2.2.1. Practical considerations
  2.2.2. Checks during lye treatment

2.3 Washing

  2.3.1. Practical considerations
  2 3.2. Frequency and duration of washing

2.4 Brine placement and fermentation

  2.4.1. Practical considerations
  2.4.2. Natural fermentation
  2.4.3. Controlled fermentation
  2.4.4. Control of chemical characteristics
  2.4.5 Corrective measures

2.5. Calculations for corrective measures

  2.5.1. Corrective using grade hydrochloric acid with a density of 1.18 - 1.19
  2.5.2. Correction by dilution and addition of brine acidified with lactic acid
  2.5.3. Combined method (addition of HCl and dilution)

2.6. Additional operations

  2.6.1. Sorting and size classification
  2.6.2. Stoning and stuffing
  2.6.3. Packing

2.7. Waste water

  2.7.1. Internal control measures
  2.7.2. Purification or disposal methods

  3 PROCESSING OF OLIVES TURNING COLOUR 53   3.1. Harvesting and transportation
3.2. Preservation and fermentation
3.3. Packing
3.4. Seasonings
3.5. Equipment and installations

  4 PROCESSING OF OLIVES DARKENED BY OXIDATION 57   4.1. Introduction
4.2. Preliminary operations
4.3. Preservation
4.4. Darkening process
4.5. Other operations
4.6. Packing and sterilisation
4.7. Waste water

  5 PROCESSING OF BLACK OLIVES 67   5.1. Preliminary operations
5.2.1. Spontaneous anaerobic fermentation
5.2.2. Fermentation by air injection
5.3. Final operations
5.4. Waste water

  6 TYPES OF DETERIORATION 77   6.1. Gas pocket formation (fish-eyes)
6.2. Putrid and butyric fermentations and "zapatería"
6.3. Changes in texture and external defects

  6.3.1. Blistering
  6.3.2. Skin marks
  6.3.3. Softening
  6.3.4. Darkening
  6.3.5. Cyanosis
  6.3.6. Green stains
  6.3.7. Yeast spots

6.4. Gas formation in packaged olives

    APPENDIX I 85   CONTROL METHODS
CHEMICAL ANALYSES
Combined acidity Free acidity
Volatile acidity
Reducing sugars in brines (semi-quantitative analysis)
Sodium chloride
Iron content of the flesh
MICROBIOLOGICAL ANALYSES
Sample taking
Microscopic examination
Microbiological examination
Culture techniques
Microorganism staining
Microbe count     APPENDIX II
101   MOST IMPORTANT BIBLIOGRAPHICAL REFERENCES FOR THE RESEARCH CARRIED OUT BY THE INSTITUTO DE LA GRASA DE SEVILLA INTO TABLE OLIVE PROCESSING 103   Bibliography (Books)
Bibliography (Papers published in journals. Classified by subject)