The Monthly Digest – Aromas and Flavours October 2017

Aromas and flavours
R & D abstracts – October 2017

Japan Flavour and Fragrance Materials Association’s (JFFMA) safety assessment of food-flavouring substances uniquely used in Japan that belong to the class of aliphatic primary alcohols, aldehydes, carboxylic acids, acetals and esters containing additional oxygenated functional groups (review)

We performed a safety evaluation using the procedure devised by the Joint FAO/WHO Expert Committee on Food Additives (JECFA) of the following four flavouring substances that belong to the class of ‘aliphatic primary alcohols, aldehydes, carboxylic acids, acetals, and esters containing additional oxygenated functional groups’ and are uniquely used in Japan: butyl butyrylacetate, ethyl 2-hydroxy-4-methylpentanoate, 3-hydroxyhexanoic acid and methyl hydroxyacetate. Although no genotoxicity study data were found in the published literature, none of the four substances had chemical structural alerts predicting genotoxicity. All four substances were categorised as class I by using Cramer’s classification. The estimated daily intake of each of the four substances was determined to be 0.007–2.9 μg/person/day by using the maximised survey-derived intake method and based on the annual production data in Japan in 2001, 2005 and 2010, and was determined to be 0.250–600.0 μg/person/day by using the single-portion exposure technique and based on average-use levels in standard portion sizes of flavoured foods. Both of these estimated daily intake ranges were below the threshold of toxicological concern for class I substances, which is 1800 μg/person/day. Although no information from in vitro and in vivo toxicity studies for the four substances was available, these substances were judged to raise no safety concerns at the current levels of intake.

Saito K et al (2017) Food Additives & Contaminants, Part A 34:1474-1484


A review on enzymatic synthesis of aromatic esters used as flavor ingredients for food, cosmetics and pharmaceuticals industries

Many sectors of industry, mainly food, cosmetics and pharmaceutics, have increased their interest in esters due to their flavor property. Flavor esters that possess an aromatic ring in their molecular structure are also known as aromatic esters. These esters are widely found in nature (fruits and plants) and the synthetic (i.e. via chemical) and natural routes (i.e. via direct extraction from nature or via biotechnology) are suitable for their biocatalysis. In this context, from the industrial point of view, enzyme-catalyzed reactions are the most economical approach to reach final green products with no toxicity and no harm to human health. The present article gives an overview of the aromatic esters synthesis, considering the main effects in the reaction media conditions and enzymes used. This review also describes applied trends in enzymatic-catalyzed reactions, pointing alternatives to production, like ultrasound-assisted reactions and process optimization of aromatic esters. Furthermore, this work presents perspectives concerning the biological potential of these esters and recent advances in their encapsulation. Lipases play an important role in the aromatic esters production, with several advantages over synthetic route. Lipase-catalyzed reactions usually follow Ping-Pong Bi-Bi or ternary complex (order Bi-Bi) mechanism. The study of the process parameters and their interaction are very important to understand the system optimization and achieve the maximum reaction yield to scale up. Aromatic esters can present some biological activities, in addition to their fragrances, which increases the interest in the encapsulation of these compounds.

Gomes Almeida A et al (2017) Trends in Food Science and Technology 69 A:95-105

Biotransformation of (+)-carvone and (−)-carvone using human skin fungi: A green method of obtaining fragrances and flavours (research)

The synthesis of optically pure compounds is increasingly in demand among the pharmaceutical, fine chemical and agro-food industries, while the importance of chirality in the activity and biological properties of many compounds has previously been established. The aim of the present study was therefore to evaluate the biotransformation capacities of (+)-carvone and (−)-carvone using the fungi Scolecobasidium sp, three lines of Cladosporium sp, Phoma sp, Aureobasidium sp and Epicoccum sp, all obtained from human skin. The seven fungi evaluated were capable of hydrogenating the activated alkene, followed by the reduction of ketone to chiral alcohol, with conversions between 9.5 and 100%, and with diastereomer excess (d.e.) of over 89% of dihydrocarveol when (+)-carvone was used as a substrate. These results demonstrate that the filamentous fungi of human skin are potential biocatalytic tools for obtaining chiral alcohols.

Dos Santos RAM et al (2017) Biocatalysis and Biotransformation (in press)

Use of non-Saccharomyces yeasts and oenological tannin in red winemaking: Influence on colour, aroma and sensorial properties of young wines (research)

Today, many non-Saccharomyces strains have been verified can be positive for the development of wine anthocyanin and aroma in different fermentation scenarios. Moreover, oenological tannins are widely used in wine industry to improve the colour profile and aroma complexity. The aim of this work is to analyze the fermentation characters of non-Saccharomyces strains and investigate the effects of pre-fermentative addition of oenological tannins on the wine components as well as sensory properties. For this purpose, five selected non-Saccharomyces strains and grape seed tannin were used to carry out the different fermentation trials. As a result, the grape seed tannins were less likely to influence growth kinetics of non-Saccharomyces strains. Schizosaccharomyces pombe has been proved can be effective to reduce the malic acid content while increase the level of vinylphenolic pyranoanthocyanin, which is positive for wine colour stability. Pre-fermentative use of oenological tannin was verified could be beneficial for the wines fermented with non-Saccharomyces regarding the improvement of wine colour, anthocyanin composition and the complexity of volatile compounds. Nevertheless, sensory analysis showed that oenological tannin could be less effective to modify the aroma impression of non-Saccharomyces wines.

Chen K et al (2017) Food Microbiology 69:51-63