Etiket Arşivleri: olive

Refined Olive Pomace Oil ( Ali İNAN )

FE-401 FOOD TECHNOLOGY
REFINED OLIVE POMACE OIL

INTRODUCTION

Olive pomace is the pulpy residue from olives after pressing.

The total of olive weight, the pomace 70 – 90 %, the stone 9-27% and the seed about 2-3%.

Pomace contains about 2-8 % residual oil.

Olive pomace oils, obtained by refining of the oil extracted from the olive pomace.

The purpose of processing the remaining pulp from olive oil production is to produce edible oil.

Olive pomace should be delivered immediately  to the extraction factory (on the same day it is produced) for drying in order to avoid any increases in acidity in the olive-pomace oil.

 After drying, pomace extracted by hexane to yield raw olive-pomace oil

Raw olive-pomace oil must be refined to become edible.

The edible product sold as olive-pomace oil is refined olive-pomace oil

PROCESS STEPS

1)DRYING THE POMACE

2)EXTRACTION

3)DISTILLATION

4)REFINING

FLOWCHART

DRYING

Halt the fermentation of the pomace.

Carried out by blowing hot air over the pomace in a drum screen.

Lower the moisture content to around 5-6%

The hot drying gases are used at high

temperatures (400°C to 700°C).

Final temperature of finished product not more than 70–80 °C.

EXTRACTION

 Preparation of the fatty pulp

 Extraction with hexane

 Desolventizing of the extracted pulp

  Types of Extractors

Batch Extractor

    Pulp placed in an upright reactor

and sprayed with the hexane.

    Commonly used for extraction.

Continuous Extractor

    Pulp washed with hexane.

DISTILLATION

Distillation of the oil-hexane mixture (miscella) in a distiller.

Try to remove the hexane from the oil as soon as possible at a temperature of around 100–110 oC.

The finished product to be lower than 150 ppm of hexane in oil.

WHY DOES IT NEED REFINING ?

 Because ;

The crude pomace oil obtained is a high acidity (more than 3% as oleic acid)

Dark green oil (high chlorophyll content)

High waxes content

Unpleasant odor and taste.

REFINING

Degumming

Neutralization

Bleaching

Winterization

Deodorization

DEGUMMING

Achieved by hydrating the gums using 0.1% concentrated phosphoric acid

Reduction of phospholipid content.

Precipitation with acids.

To remove precipitate.

NEUTRALIZATION

 The crude pomace oil obtained is a high acidity (more than 3% as oleic acid)

Removes nearly all free-fatty acid by converting them into oil-insoluble soaps.

The oil-insoluble soaps are separated by centrifuge in the batch neutralizers.

Chemical reaction with caustic soda.

Caustic soda + Acid        Soap + Water

BLEACHING

Remove the unpleasant colors of the alkali neutralized pomace oil

The oil is heated to 100℃.

Stirred with the bleaching earth for 30 min under a vacuum (30-40 mmHg)

Bleached oil removed from the activated earth and charcoal by filtration.

WINTERIZATION

The elimination of any compound that might cause the final product to appear cloudy

Removes waxes and high melting triacylglycerols.

The process is based on crystallization (5–8 ℃).

Increase the size of crystals.

The crystals are separated with filtration.

DEODORIZATION

 Final treatment step in the refining process.

Treatment of undesirable odours.

150 ℃ to  260 ℃.

Steam is used to better tastes and aromas

 Absolute vacuum between 0.2– 0.4 mbar.

IMPORTANT ANALYSIS

 1)DETERMINATION of FATTY ACID CONTENTS

 2)DETERMINATION of WAXES

 3)DETERMINATION of FREE FATTY ACIDS (FREE ACIDITY)

 4)DETERMINATION of PEROXIDE VALUE

 5)DETERMINATION of STIGMASTADIENES

 6)DETERMINATION of STEROL COMPOSITION

 GENERIC CHEMICAL COMPOSITION PARAMETERS

QUALITY PARAMETERS

Thanks for your attention


Olive ( Engin BİLGEN )

—OLIVE

—Prepared by

—Engin BİLGEN

HISTORY OF OLIVE

COMPOSITION OF OLIVE

OLIVE PRODUCTION IN THE WORLD

PROPERTIES OF CLIMATE

TYPES OF OLIVE

PROCESSING OLIVE

ECONOMY

OLIVE OIL

—History of olive

The olive was spread from Iran, Syria and Palestine to the west of the Mediterrenean basis 6000 years ago

It’s among the oldest known cultivated trees in the world.

The olive tree was a symbol in ancient Greece.

An olive tree branch was the award to the winners in Olimpia.

Olives have been found in Egyption tombs from 2000 years BC.

The use of oil is found in many religions and cultures.

Turkey is one of the major producers of olives in the region.

Today Turkey is the 4th largest olive oil producer in the world.

—COMPOSITION OF OLIVE

Chemical composition of the different parts of olive(% fresh weight)

OLIVE PRODUCTION IN THE WORLD

PToday olives are commercially produced in Spain, Italy, France, Greece, Tunisia, Morocco, Turkey, Portugal, China, Chile, Peru, Brazil, Mexico, Angola, South Africa, Uruguay, Afghanistan, Australia, New Zealand, and California

—OLIVE CULTIVATION IN TURKEY

The climatic characteristics of Anatolia represent an additional plus for olive cultivation in Turkey.

The winters are mild and rainy, spring and fall are cool with occasional showers, and the summers are dry and slightly breezy, a climate suited to the olive

Marmara Region

Aegean Region

Mediterranean Region

—PROPERTIES OF CLIMATE

TYPES OF OLIVE

—PROCESSING  OLIVE

HARVEST AND TRANSPORTATION

SIZING, SORTING

WASHING

BRINE AND FERMENTATION

CHOOSING, CLASSIFYING, PACKING

Gemlik Method

Salt-Folding Method

Salt Olive

Black Olive Production by Giving air

Quick Method(Comfytype) Olive Production

Can Olives

Kalamata Olive

Drawn Olive

—ECONOMY

—Production percentages of the countries;

Spain -> 25%

Turkey -> 12%

USA -> 8%

Syria ->8%

Morocco -> 7%

Greece -> 7%

Italy -> 5%

Others -> 28%

—OLIVE OIL

—TYPES OF OLIVE OIL

1.EXTRA VIRGIN OLIVE OIL: Oleic acid may not exceed 1%

2.VIRGIN OLIVE OIL: Oleic acid may not exceed 2%

3.ORDINARY VIRGIN OLIVE OIL:Oleic acid may not exceed 3.3%

4.LAMPANTE VIRGIN OLIVE OIL:Acidity of more than 3.3%. Not fit for direct consumption

5.REFINED OLIVE OIL: Oleic acid may not exceed 0.3%

6.POMACE OLIVE OIL: It is made of the oil extracted from olive pomace using solvents

7.OLIVE OIL: Acidity may not exceed 1.5%

Thank you for your attention

Characterization of Turkish Olive Oils by Using Multivariate Statistical Methods

Characterization of Turkish Olive Oils by Using Multivariate Statistical Methods
Aytaç S.GÜMÜŞKESEN, Fahri YEMİŞÇİOĞLU
İsmail EREN
Ege University, Engineering Faculty,
Food Engineering Department, İzmir- TÜRKİYE

INTRODUCTION

Virgin olive oil is a food with high nutritional qualities; hence, it is chosen for cooking and dressing by consumer from Mediterranean countries, which represent the world’s largest production area (98% of world’s olive oil).

Factors Affecting Olive Oil Composition

The flavor of extra virgin olive oil has particular desirable organoleptic and nutritional properties. However, chemical composition of the olive oil together with its physical and sensory characteristics mainly depends on several factors such as;

Olive variety

Environmental factors (soil, climate, growing location)
Agronomic factors (irrigation, fertilization)
Cultivation (harvesting method, maturity)
Technological factors (storage, extraction system)

 

Olive Oil Processing

OLIVE OIL PROCESSING

Originating in Asia, the olive is one of the oldest crops known to mankind. It later spread through all the countries bordering Mediterranean Sea where 98% of the world’s olive trees are concentrated and over 90% of the world’s olives are produced.
The table below shows how the olive is distributed by country:

The composition of olive fruits depends on the stage of ripeness or maturity. In ripe fruit, the kernel makes up 2-3% of the total weight, the stone some 13-23%, the pulp (mesocarp) some 65-92% and skin 1-2%.

 

Olive Oil Production

1. Cleaning the Olives. Stems, twigs and leaves are removed and the olives may or may not be cleaned with water to remove pesticides, dirt, etc. Rocks and Sand will quickly wear out a centrifugal decanter or oil separator, reducing life span from 25 to as little as 5 years.

2. Grinding the olives to paste Stone Olive Mills : Stone rollers or wheels roll in circles on a slab of granite to grind the olives into a paste

Advantages

can be adapted to olive and pit size to optimize paste characteristics

doesn’t cut the skin, releasing less chlorophyll

formation of larger size drops of oil, minimizing mixing times

paste isn’t heated

less phenols so less bitter oil

Olive Fermentation Presentation

•OLIVE FERMENTATION

•The main use of raw olives, is as olive oil—
•more than 90% of the total worldwide olive production is used for oil
•7% to 10% are consumed as table olives.
•Currently, four countries— Italy, Spain, Greece, and Turkey —are responsible for 75% of the total worldwide olive production (9-15 billion Kg)
•Four fundamental types have been established;
•-green
•-turning color
•-natural black
•( for these types they refer to color of fruit as a raw material, color does not change during processing)
•-black ( harvested as turning color and turns to black during oxidation in an alkaline during processing)
•Bitterness of fruit can be eliminated completely and quickly by alkaline hydrolysis, sodium hydroxide solutions prior to fermentation and by storage in brine or dry salt.
•Olive fruit
•Pulp 70-90 %
•Stone 9-27 %
•Seed 1-3 %
•Pulp %
•Moisture 50-75
•Oil 6-30
•Soluble reducing sugar 2-6
•Soluble non-reducing sugar 0.1-0.3
•Crude protein 1-3
•Fiber 1-4
•Ash 0.6-1
•Others 6-10
•Major soluble sugars are glucose, fructose, sucrose, xylose and rhamnose .
•Also contains 0.5-1 % mannitol .
•Pulp contains 1-3 % tannic acid.
•Oleuropein: responsible for the bitterness.
Catechol oxidase: enzyme responsible for the color change of fruit from green to brown.
•Fermentation tanks are used to be wood but not now.
•Concrete tanks are still in use ( height should be less than 2.5 m to eliminate pressure problems on olives).
•Concrete tanks should be painted with synthetic paints or covered with polyesters.
•Polyester and fiber glass tanks are the best ones and nowadays commonly used.
•Underground fermentation tanks
•Spanish style pickled green olives in brine
(1/3 of all production, lactic ferm. is fundamental)
The fruits are picked( firm and light green)
–Starting phase:
–Alkaline (1.3-2.6 % w/ v NaOH, 6-10 h, 28 C )
–Hydrolysis of oleuropein and formation of organic acids from sugars.
•Fresh, green olives stay in the lye 9 to 12 h.
Test the penetration of the lye: Use phenolphthalein indicator
The penetrated part: : bright magenta
the acidic flesh: near the stone will still be white.
the olives are washed , to remove the lye. ( pH 8 % salt necessary.
•Pasteurization to promote extended shelf-life is optional.
•Natural black olives in brine( Greek Method):
•( 1/3 of all production, Yeast dominates and minor lactic fermentation).
• naturally ripe, fully matured and dark-purple fruits
•differences between Greek-style and other olive types.
•1- naturally black when they are harvested ( California-style black olives rely on oxidation to generate black pigments.)
•2- Greek-style olives are not lye-treated,( more bitter flavor).
•3- the fermentation by lactic acid bacteria, yeast, non-lactic acid bacteria .
•Starting phase : No starting phase.
Main phase
•non-lactic organisms (Pseudomonas, Enterobacteriaceae) exist in the brine, for several weeks. ( so includes lactic, acetic, citric, malic acid, CO2, and ethanol.
Lower brine concentrations (5% to 10%) may contribute to the more diverse flora that develop in these olives.
•Fermentation in brine.( 6 % salt, concrete tanks lined with paraffin or epoxy resins).
•Yeast predominate ( Candida, Pichia, Kleockera , Torulopsis, Deboramyces)
• Lactic acid bacteria present ( if salt con. 0.6 % L. acid ) color will be lighter ( Similar to black olives treated with alkaline , it is not desired.)
•Final pH is 4.5-4.8, salt concentration is > 10 %
•After fermentation is completed, it exposed to air to oxidize to improve skin color.
Final phase
• Conservation in brine.
Antifungal treatment:
sorbic acid 0.075% is the most efficient preservative
0.075% benzoic acid
0.032% calcium proprionate.
Pickled black (ripe black ) olives in brine
( American, Californian, style)
Straw-yellow to cherry-red olives are graded according to color and size to insure uniform lye penetration
•Alkaline treatment ( 1-3 % NaOH )
•place into water,
•inject air under pressure to oxidize polyphenolic compounds for complete blackening of the skin
•wash several times
•add 0.1 % iron gluconate to last wash water to stabilize color
•put in to brine ( 3 % salt )
•bottled in tin cans or glass bottles
•sterilize (116 C for 1 hr)
•Final pH: 5.8-7.9, salt 2-3 %
Some Turkish style olives produced
•Gemlik style black olive production :
•Harvest olives: skin is black and pulp is purple,
•If it is going to be stored longer than 14 h keep it in a solution ( of 0.67 % L acid, 1 % acetic acid, 0.03 % sodium benzoate, and 0.3 % potassium sorbate .)
•washing ( 2-3 days)
•Put them into fiber glass tanks ( 10 tons)
•add brine solution 10 % salt,
•0.15 g/kg iron gluconate or iron oxalate to improve color,
•1 % inoculum L. plantarum
•first two months adjust salt conc. to 10 %
•Fermentation temperature is approximately 20 C.
•Try to prevent contact of olives with air at the surface of tank.
•If sugar concentration is not sufficient add 0.5-1 % molasses during third or forth week of fermentation.
•Lactic acid concentration should be not less than 0.9 %.
•Prevent Mold growth on the surface, it uses lactic acid and product softens.
•( fermentation time is approximately 6 months ) –
•Fill cans under N2 or CO2 gas and pasteurize.
•low salt conc. for first 20 days then increase to 10 % , shorten fermentation time to 2-3 months.
Cut ( çizme) green olives
•Olives are cut from 2-4 place
•Put into 2-3 % salt solution ( no alkaline treatment)
Change its solution twice a day until bitterness is removed
put into 8-10 % salt solution and 8-10 days of fermentation
packaging ( in 5-8 % salt solution, 1 % citric acid, olive oil)
Olive produced in baskets ( sele zeytini)
•Ripe olives are placed in a basket as one layer olive and one layer dry salt until to the top of basket and covered with cloth
•turn these olives (olive release its water)
•in 3-4 weeks no bitterness left ( weight loss is 20-30 %, no air movement is wanted
to prevent drying of olives)
•Wash
•pack and cover with olive oil
Hurma zeytin
•Single olive type that can be consumed immediately after harvest.
•( Grown at Urla and Karaburun: very small amount, economically it is not important )
• Mold ( Phomo olea) grows on the tree and it breaks down oleuropein, olive is not bitter when it is harvested.

DEFECTS IN OLIVE PICKLES

•1- Film formation on the surface of tanks( soft pickles):
•called kefeke in Turkish, especially during summertime. ( color of the film changes as White to green to red to finally gray).
•Mo of this film breaks down lactic acid, supports the growth of mo, breaks down pectin so olive softens.
•softening : if sufficient lactic acid is not produced or salt conc. is very low.
• breakdown of fatty acids: gives bitter taste( called yağlanma)
•To prevent film formation we should tightly close surface of the tank.
•2-Slime formation
• Due to low acid and salt, slime forming m.o grows ( brine should be changed)
•3-Darkening:
•Occurs in green olive pickles due to contact with air.
•iron contamination cause darkening by reacting with polyphenols and forming iron tannat.
•If darkening is not intense, keeping olives in 1-2 % H2SO4 solution can be helpful to remove dark color
•4-Air space formation: (blistering)
•Due to high temperature and high alkaline conc. air space forms just underneath the skin of olive.

Table Olive Fermentation

Özet

Türkiye dünyanın en büyük zeytin üreticilerindendir. Sofralık zeytin fermentasyonu, salamuranın tuz yoğunluğuna, pH’ sına, uygulanan ön işlemlere, mikrofloranın komposizyonuna ve havalandırılma yapılıp yapılmadığına bağlı olarak zeytinde gaz ceplerinin oluşmasına ve zeytinin yumuşamasına, büzüşmesine, ve kısa raf ömrüne neden olabilir. Düşük tuz yoğunluğu, pH kontrolu ve havalandırma kalitenin iyileşmesine ve raf ömrünün uzamasını sağlamaktadır. Starter kültür uygulamaları kaliteyi daha da iyileştirebilir.

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