Day 1 :
Keynote Forum
Isaac Williams Ofosu
Kwame Nkrumah University of Science and Technology, Ghana
Keynote: Acrylamide content in alkalized roasted cocoa beans based on K2CO3
Biography:
Isaac Williams Ofosu completed his Doctoral studies in Food Science and Technology from Kwame Nkrumah University of Science and Technology, Kumasi, Ghana. He is a Senior Lecturer and facilitates learning and research in Food Systems Chemistry, Toxicology and Risk. He has published over 20 papers in reputed journals. He serves as a Viewer and has also been serving as Editorial Board Member in international journals.
Abstract:
The Dutching process of cocoa mass production ensures consistency of its brown color, flavor and dispersability. However, acrylamide, a known probable carcinogen which is one of known by-products of browning reactions, is linked to the strength of alkalis used in the Dutching process. This study used Response Surface D-optimal, 20 experimental runs to determine acrylamide content of beans after using treatment factors; temperature (110-160oC), time (20-50 min) and K2CO3 (10-70% w/v). Subsequently, the alkalized cocoa masses were treated to obtain extracts containing acrylamide using QuEChERS method. The concentrations of the acrylamide were determined using HPLC after which the data was processed by fitting a cubic process order followed by diagnostics to remove outliers. The results yielded optimized process conditions of treatment to yield low acrylamide content, which was later validated to be 7.7×10-2 mg/g, at alkali concentration of 29.17% and roasting temperature - time system of 110oC and 20 min respectively. Though the validated acrylamide content was relatively lower than what has been reported in some European markets, it was found to be extremely high in other markets. This suggests that the application of K2CO3 could hold promise of lowering acrylamide concentrations. However, after exposure studies, the validated acrylamide yielded a probable risk of ‘4 in 1000’ adults and ‘2 in 100’ young children consumers of chocolate products which were highly unacceptable relative to the de minimis (‘1 in 1,000,000’). Thus, based on the de minimis risk, further control measures must be sought to produce safer alkalized cocoa masse.
- Neutraceuticals and Medicinals Foods
Session Introduction
Ratchadawan Puangpradab
Queen Sirikit Botanic Garden, Thailand
Title: Antioxidants and nutritional properties of selected edible plants for functional food
Biography:
Ratchadawan Puangpradab has completed her MS degree (Organic Chemistry) from Chiang Mai University. She is the Researcher of Phytochemical Loboratory, Research and Consevation Unit, Queen Sirikit Botanic Garden, The Botanical Garden Organization. Her expertise field is study of chemical compounds from plants (extraction, separation, purification and structure identification) and Bioassay testing.
Abstract:
Enrichment of diet with edible plants as sources of antioxidants may have beneficial effect on human health. Therefore, the determination of bioactive compounds content in their comsumable parts presents important tasks for their evaluation as natural source of antioxidants for human diet. In this study, the antioxidant properties of six edible plants in northern Thailand that have been used as food and medicinal plants including Acmella oleracea (L.) R.K.Jansen (Asteraceae), Raphanus sativus Linn. var. caudatus (Brassicaceae), Dipterocarpus obtusifolius Teijsm. ex Miq. (Dipterocarpaceae), Caesalpinia mimosoides (Leguminosae-Caesalpinioideae), Embelia sessiliflora Kurz (Myrsinaceae) and Ficus lacor Buch.-Ham. (Moraceae) were examined in both water and alcohol by DPPH and ABTS radical scavenging assays as well as total phenolics content and total flavonoids content. The samples of plants being investigated were selected from parts used which were whole plants, fruits, flowers, infloresences, fruits and syconium respectively. The nutritive values were evaluated for crude fiber, phosphorus, potassium, calcium, magnesium, sodium and iron. These samples tested could be a valuable source of antioxidants for addition to dishes or fresh consumption. These findings showed that the tested samples could be considered as new sources of natural antioxidants for nutritional supplements or pharmaceutical industries.
Mustapha Najib
University of Lille, France
Title: The mechanisms of the heat-induced interactions of milk components during the process of Qishta: A Lebanese cream
Biography:
Abstract:
Milk and milk products are nutritious foods which contain numerous essential nutrients. They are considered as a source of calcium, phosphate, riboflavin, vitamin B12, proteins and fat. There are several principal categories of milk products such as liquid/beverage milk, cheese, milk powders, concentrated milks, fermented milk products, butter, some of which are produced from byproducts of other milk-products, ice-cream, infant formula, creams, protein-rich products, and lactose. In addition, several product sub-categories exist and many are defined by the process they have been subjected to. Products may be altered by acid, enzymes or microorganisms, or a combination of these. The most important part of milk processing has turned to be the heat treatments, demonstrating the common practice to restrain the microbial development in milk. Qishta is one of the traditional dairy products that exist in Lebanon. It is a heat-treated dairy product made by subjecting a small sector of a large shallow stainless-steel pan that is filled with whole milk, to high temperature. Qishta is related to the cheese family, especially to cream cheese varieties due to the presence of milk proteins as well as their particular coagulation process during Qishta development. Protein’s aggregation is considered as a key point during the process of Qishta. During the Qishta preparation, heat treatment of milk induces an increase in acidity, due to the degradation of lactose. This last is involved with the proteins in the Maillard reaction. The dimer of β-Lg dissociates between 30 and 55°C, but these changes are reversible and the monomers can rebound by cooling if the temperature does not exceed 60°C. When temperatures are above 60-70°C, the tertiary and also partly secondary structure of the monomer starts to unfold, leading to exposure of the free thiol group (Cys121) and hydrophobic parts of the residues chain, resulting in a reactive monomer. The main aggregates formed as a consequence of heat treatment of milk, are complexes formed by aggregation of denatured whey proteins and complexes between β-Lg and κ-casein on the surface of the casein micelles via disulphide bonds and hydrophobic interactions.
Ratchuporn Suksathan
Queen Sirikit Botanic Garden, Thailand
Title: Nutritions and phytochemicals of edible flowers in tea infusions and their antioxidant properties
Biography:
Ratchuporn Suksathan has completed her Bachelor’s degree and Master’s degree in Botany from Faculty of Science and PhD from Faculty of Pharmacy at Chiang Mai University, Thailand. She is the Researcher in Research and Product Development, Department of Research and Conservation, Queen Sirikit Botanic Garden, Chiang Mai, Thailand. She has published more than 12 papers in phytochemistry, botany, biological activities and natural products. She is the Inventor of more than seven granted Thai petty patents involved in natural products.
Abstract:
Flowers are used as food ingredients and medicinal purpose in many countries including with flavouring tea. A growing awareness of consumer health benefits is leading to a new product research from edible flowers to be an alternative option for the natural food and beverage markets. Hot and cold tea formulas were developed from edible flowers, which were used as medicinal plants, Bauhinia variegata L., Shorea roxburghii G.Don and Viburnum sambucinum Blume. The flowers of these three species were mixed for health benefits and distinct flavour properties. These plants are rich source of natural antioxidants. Their phytochemicals were evaluated for alkaloids, flavonoids, anthocyanins, saponins, tanins, polyphenols, steroids and terpenoids. The investigation of plant nutritions for example, protein, lipid, ash, dietary fiber, carbohydrate, calcium, potassium, sodium, iron, vitamin C and energy were completed. Total phenolics and flavonoids contents were obtained for both water and ethanolic extracts of each plant sample. Antioxidant activities of water and ethanolic extracts and formulations were estimated using DPPH radical scavenging activity and ABTS radical scavenging activity compared to Camellia sinensis (L.) Kuntze. Sensory evaluations were done using a nine-point hedonic scale with thirty trained panelists. Two late winter season tea infusions, “Floral infusion” or “Hot Tea” and “Ready to drink” or “Cold Tea” were achieved with impartment for colour, aroma, flavour, astringency and overall acceptability to mixtures and several health benefits.
Biography:
Suh-Jen Jane Tsai has studied Chemistry at the Ohio State University, Columbus, Ohio, USA and obtained her PhD degree in 1984. She has joined the faculty at Department of Applied Chemistry, Providence University, Taichung, Taiwan since 1985. She was the Chair of the Department of Applied Chemistry and Dean of the College of Science. She has been a distinguished Professor for several years.
Abstract:
Trans-resveratrol (trans-3,5,4'-trihydroxystilbene, t-RSV) is common found in grape and red wine. t-RSV has significant effects on lipid metabolism, anti-inflammatory, antioxidant, free radical scavenging, anti-allergy and cardiovascular diseases. Besides t-RSV is also an effective cancer preventive medication, can effectively inhibit tumor growth, and cancer formation. Polydatin, also called piceid (3,5,4'-trihydroxystilbene-3-O-β-D-glucopyranoside) is a stilbenoid glucoside and is a natural precursor of resveratrol. It can be found in the bark of Picea sitchensis. It can also be isolated from the Japanese Knotweed. Trans-polydatin is known to induce β-defensin production and reduce inflammatory response. Quercetin, (2-(3,4-dihydroxyphenyl) -3,5,7-trihydroxy-4H-chromen-4-one), is a flavanol, that is commonly found along with resveratrol in grapes and red wine. In nature, resveratrol and piceid exist in both trans- and cis-isomeric forms, which may have different biological effects due to their diverse chemical structures. Trans-isomer is biologically active while cis-isomer has less effect. However, trans-forms may be converted to cis-forms with the exposure to UV irradiation. LC-MS/MS has been one of the most popular instruments for the determination of various components in a diversity of samples. The effective pretreatments for grape, redwine and pomace (also called marc) were established for getting reliable results. Important analytical parameters were also studied. The reaction mechanisms involved in the LC-MS/MS determination were studied. The precision, accuracy, detection limit and reproducibility of the proposed method were evaluated to validate the reliability of the proposed method.