1 METHODS OF IDENTIFICATION OF NATURAL JUICE Martin Kubík Czech Agriculture and Food Inspection Authority Workshop on Estimation of Natural Juices in Nectars, Cairo, Egypt, November 2014

2 Introduction

3 Prague

4 Czech Agricultural and Food Inspection Authority (CAFIA) state administration body (subordinate to the Ministry of Agriculture) state authority responsible for supervision of safety, quality (autenticity) and labelling of foodstuffs.

Experience in field of fruit juices 1996 first contact with European Fruit Juice association (AIJN) – gain knowledge and experience selected methods of analysis for authenticity evaluation introduced (accredited) first inspections performed on the market large proportion of adulterated products (32% non-compliant) 1998 situation on the Czech market improved 1998 – 2014 regular controls including drinks and nectars 5

6 Fruit (vegetable) products definitions For inspection of fruit juice it is necessary to know what individual products mean It is necessary to have clear definitions of the products What do you imagine under expressions juice, nectar?

7 Fruit (vegetable) products definitions Definitions in Codex Alimentarius and EU Directive Generally  juice (100% of fruit)  nectar (<100% of fruit)  drink (< of fruit nectar)

8 Fruit (vegetable) products definitions Codex Alimentarius Standard CODEX GENERAL STANDARD FOR FRUIT JUICES AND NECTARS (CODEX STAN ) Fruit juice is the unfermented but fermentable liquid obtained from the edible part of sound, appropriately mature and fresh fruit or of fruit maintained in sound condition by suitable means including post harvest surface treatments applied in accordance with the applicable provisions of the Codex Alimentarius Commission. The juice is prepared by suitable processes, which maintain the essential physical, chemical, organoleptical and nutritional characteristics of the juices of the fruit from which it comes.

Fruit juices Direct juice - directly expressed by mechanical extraction processes - considered as higher quality, fresh more expensive Juice from concentrate -by reconstituting concentrated fruit juice with potable water that meets the authenticity criteria (must have same organoleptic, physical and chemical characteristics as direct juices -required minimum Brix 9

Fruit juices Single fruit obtained from one kind of fruit Mixed obtained by blending two or more juices (multifruit) or juices and purées, from different kinds of fruit Limited number of approved additives or ingredience (mostly technological aid or taste adjustment) 10

Fruit nectar Fruit Nectar is the unfermented but fermentable product obtained by adding water with or without the addition of sugars and/or food additive sweeteners. That product moreover must meet the requirements defined for fruit nectars (fruit content) Required fruit content 25 – 50% 11

EU legislation COUNCIL DIRECTIVE 2001/112/EC relating to fruit juices and certain similar products intended for human consumption definitions and requirements comparable to Codex Alimentarius 12

Methods of adulteration – practical examples dilution with water (overdilution) – easy to carry out, but also easy to detect (lower Brix and density) masking examples: orange juice from concentrate - Brix 10,2 apple direct juice – Brix 9,3 13

Methods of adulteration – practical examples dilution with water and sugar(s) addition – Brix and density are within range – sugar composition could be different than typical but need not to be – other characteristic parameters are lower – isotopic composition could be different 14

Methods of adulteration – practical examples pulpwash and peel extract addition citrus juice should be prepared only from endocarp (legal requirement) – case of citrus juices – detection – high content of flavonoids 15

Example orange juice with peel extract (2013) complaint from consumer - fresh direct juice – extremely high unusual taste price 160 CZK/litr (8 USD) sample to the laboratory sensory analysis (visible particles of peel, extremely bitter taste) high content of peel analytically confirmed (extremely high hesperidine content – 8-10x higher than standard range) Sample was not only orange juice but also meshed peel

Methods of adulteration – practical examples artificial product – nearly no fruit content labeled as 100% orange juice, based on artificial aroma, colours, sugars, acids.... checked for several parameters nearly all extremely low (estimated fruit content < 20% 17

Methods of adulteration – practical examples substitution of fruit for cheaper one -total or partial substitution chokeberry in blackcurrant juice blackberry in blood orange juice black carrot extract in pomegranate juice apple in strawberry juice Detection by analysis of characteristic markers – sorbitol, anthocyanins, polyphenols etc. 18

Anthocyanin profile for pomegranate juice (source Eurofins) Delpin-3,5-digluc Cyan-3,5-digluc Delpin-3-gluc Cyn-3-gluc Unknown

Anthocyanin profile for adulterated pomegranate juice (source Eurofins) Acylated “cyanidins” Pomegranate juice plus black carrot extract Peaks of pomegranate

Methods of adulteration – practical examples substitution direct juice for juice from concentrate detection of water addition by isotopic methods 21

Methods of adulteration – practical examples not genuine flavour flavour of juice from concentrates not restored analysis of aroma profiles by chiral GC or GC-IRMS 22

Methods of identification (authentication) of natural juices necessary to have knowledge about composition of authentic juices have knowledge about suitable methods of analysis be able to perform that methods of analysis well (equipment, skils, experince) be able evaluate quality and authenticity (knowledge + experince) 23

Composition of authentic juice be aware all possible deviations caused by: –geographical origin –variety –season –irigation –fertilizing –technology 24

Sources of reliable data on fruit juices composition Databases (guidelines) are available e.g. from AIJN (European Fruit Juice Association), SGF... other data from scientific articles or data from own measurements (authentic samples) AIJN SGF QUID Thematic Network Seminar, Teddington

AIJN reference guidlines - Code of Practice acceptability parameters for individual fruits – section A absolute quality requirements (mandatory) – section B criteria for evaluation of identity and authenticity –valid conclusion, regarding the authenticity of a particular sample, can only be reached providing the whole analytical picture has been subject to expert interpretation for 20 different fruits 26

AIJN Code of Practice - example acceptability parameters for individual fruits – section A absolute quality requirements (mandatory) – section B criteria for evaluation of identity and authenticity - valid conclusion, regarding the authenticity of a particular sample, can only be reached providing the whole analytical picture has been subject to expert interpretation 27

AIJN Code of Practice - example 28

AIJN Code of Practice - example 29

Analytical approaches conventional analysis – require scale of analytical instruments for overall assessment –titration, gravimetry, spectrometry, HPLC, GC, IRMS, SNIF-NMR expensive, time consuming but official approach suitable for following legal steps....targeted approach (specific problem) 1H-NMR profiling –very fast method (fingerprint profiling + chemometry) –reference database of authentic samples necessary –confirmations by conventional methods –Metabolomics (LC-MS, LC-MS DART)

Analytical approaches senzory analysis –rough estimate –could help to sort out samples –assessors have to be trained, easy to be influenced by experience 31

Methods of analysis Staded in CODEX STAN 247 IFU and/or EN standards 32

Thank you for your attention 33