Valorisation of Compounds with High Nutritional Value from Cocoa By-Products as Food Ingredients and Additives

Thesis jury:

Chiara CORDERO (Università degli Studi di Torino, Chair) Stéphanie POCHET (Université libre de Bruxelles, Secretary) Vera LAVELLI (Università degli Studi di Milano)

Giorgia SPIGNO (Università Cattolica del Sacro Cuore)

Giuseppe ZEPPA (Università degli Studi di Torino, Supervisor) Caroline STÉVIGNY (Université libre de Bruxelles, Supervisor)

Valorisation of Compounds with High Nutritional Value from

Cocoa By-Products as Food Ingredients and Additives

Thesis presented by Olga ROJO POVEDA

with a view to obtaining the PhD Degree in Biomedical and Pharmaceutical

Sciences (ULB - “Docteur en Sciences Biomédicales et Pharmaceutiques”)

and in Agricultural, Forestry and Food Sciences (UniTo)

Academic year 2020-2021

Supervisors: Professor Caroline STÉVIGNY (Université libre de Bruxelles)

RD3 Department-Unit of Pharmacognosy, Bioanalysis and Drug Discovery

and Professor Giuseppe ZEPPA (Università degli Studi di Torino)

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Table of contents

Acknowledgements ... i

Table of contents ... iii

Abbreviations ... v

Abstract ... vii

GENERAL INTRODUCTION ... 1

1. The cocoa bean shell ... 3

2. Nutritional and chemical composition ... 5

2.1. Proximate composition – Moisture, ashes, proteins, fats and carbohydrates ... 5

2.2. Dietary fiber ... 8

2.3. Phenolic compounds ... 9

2.4. Methylxanthines ... 11

2.5. Minerals and vitamins ... 12

3. Applications ... 13

3.1. Food applications ... 13

3.2. Utilization as feedstuffs ... 14

3.3. Uses in industry and other applications ... 16

4. Biofunctionality and potential health benefits ... 17

4.1. Antibacterial activity and anticariogenic effects ... 18

4.2. Antiviral properties ... 22

4.3. Action on cardiovascular health ... 22

4.4. Anticarcinogenic action ... 23

4.5. Antidiabetic activity ... 23

4.6. Other biofunctional properties ... 24

5. Safety aspects ... 25

5.1. Heavy metals ... 25

5.2. Mycotoxins ... 26

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RESULTS AND DISCUSSION ... 33

PART 1 – COCOA BEAN SHELL CHARACTERIZATION ... 35 CHAPTER 1.1: Determination of polyphenolic profile by RP-HPLC-PDA

analysis and spectrophotometric assays for the chemometric classification of

cocoa bean shells ... 37 CHAPTER 1.2: Assessment of volatile fingerprint by HS-SPME/GC-qMS

and E-nose for the classification of cocoa bean shells using chemometrics... 79 CHAPTER 1.2.1: Analytical dataset on volatile compounds of cocoa bean

shells from different cultivars and geographical origins ... 107 PART 2 – COCOA BEAN SHELL-BASED FUNCTIONAL FOODS ... 117

CHAPTER 2.1: Effects of particle size and extraction methods on cocoa bean

shell functional beverage ... 119 CHAPTER 2.2: In vitro bioaccessibility and functional properties of phenolic

compounds from enriched beverages based on cocoa bean shell ... 147 CHAPTER 2.3: Physical properties and consumer evaluation of cocoa bean

shell functionalized biscuits adapted for diabetic consumers by the

replacement of sucrose with tagatose ... 169 CHAPTER 2.4: Polyphenolic and methylxanthine bioaccessibility of cocoa

bean shell functional biscuits: metabolomics approach and intestinal

permeability through Caco-2 cell models ... 191 PART 3 – CBS APPLICATIONS WITH PHARMACEUTICAL APPROACH ... 223

CHAPTER 3.1: Evaluation of cocoa bean shell antimicrobial activity with a

metabolomic approach for tentative active compound identification ... 225