Anne-Marie Seuvre

Aroma transfers in and through plastic packagings : Orange juice and d-limonene. A review. Part I: Orange juice aroma sorption

Orange juice and one of its major volatile constituents, d-limonene, were probably amongst the first food products to be thoroughly studied. Yet, no extensive literature review has been undertaken in order to obtain a general and accurate description of the sorption and diffusion phenomena. This review underlines the effects of packaging on the organoleptic quality of citrus juices; it therefore presents a focused interest on d-limonene mass transfer experimental results with a variety of plastic polymers. Part I deals with first, loss of organoleptic quality of orange juice during storage and d-limonene sorption is discussed. Second, generalites are presented concerning volatiles transfer measurements and two tables summarise the experimental d-limonene sorption, diffusion and permeation results we could obtain easily, after which we offer our comments.

Aroma Transfers in and through Plastic Packagings: Orange Juice and d-Limonene. A Review. Part II: Overall Sorption Mechanisms and Parameters-a Literature Survey

Nowadays, the quality of foodstuffs has more than ever included the notion that packaging1 contact is not always wholesome. It can alter the packaged food product by flavour scalping and can also affect the food by off-flavour release. Much research has been carried out to better understand the mass transfers involved with various synthetic polymeric films. Orange juice and one of its major volatile constituents, d-limonene, were probably amongst the first food products to be thoroughly studied. Yet, no extensive literature review has been undertaken in order to obtain a general and accurate description of the sorption and diffusion phenomena. This review underlines the effects of packaging on the organoleptic quality of citrus juices; it therefore presents a focused interest on d-limonen mass transfer experimental results with a variety of plastic polymers. Part II deals with sorption mechanisms and parameters mentioned in the literature which are described to better understand the effect of the permeants and polymers physico-chemical characteristics as well as some external factors of d-limonene sorption. Finally, current theoretical considerations for the prediction of d-limonene sorption are presented chronologically in order to keep investigators up-to-date with what has already been done.

Aroma behaviour during steam cooking within a potato starch-based model matrix

To help understand the organoleptic qualities of steam cooked foods, the kinetics of aroma release during cooking in a potato starch based model matrix was studied. Behaviour of components having a major impact in potato flavour were studied using solid phase micro extraction-gas chromatography (SPME-GC). Evolution of microstructure of potato starch model-matrix during steam cooking process was analyzed using environmental scanning electron microscopy (ESEM). Both aroma compounds that are naturally present in starch matrix and those that were added were analyzed. Both the aroma compounds naturally presented and those added had different behaviour depending on their physico-chemical properties (hydrophobicity, saturation vapour pressure, molecular weight, etc.). The physical state of potato starch influences of the retention of aromatized matrix with Starch gelatinization appearing to be the major phenomenon influencing aroma release.

Physico-Chemical Interactions in the Flavor-Release Process

The perception of flavor is induced by the release of aroma compounds in the vapor phase. The olfactory perception is not only related to the nature of aroma compounds initially present in the food, but also to their distribution between the different phases. After a description of the interactions established between the aroma compounds and different constituents of food, this chapter looks at physico-chemical characteristics of aroma compounds and at the composition and properties of food matrices. Then, in order to understand the behavior of aroma compounds in the matrices, study methods of interactions are described. The assessment of the release is done by determining the partition coefficients and mass transfer between phases. The conclusion opens the way on the preservation of aroma compounds.

Antioxidant activity and release kinetics of caffeic and p-coumaric acids from hydrocolloid-based active films for healthy packaged food

Sustainable hydrocolloid-based films containing natural antioxidants, caffeic and p-coumaric acids at different concentrations of 0.5%, 1%, 5%, and 10% w/w of polymers, were designed for packing fatty foods. Antioxidant activities and kinetics for all film formulations were assessed using radical scavenging activity (DPPH), reducing power, and iron chelating ability. Release kinetics of the antioxidants from the films into a food simulant (96% ethanol) were analyzed. The intermolecular interactions between antioxidants and polymers chains were assessed by Fourier transform infrared attenuated total reflectance (FTIR-ATR) and related to the film properties. Antioxidant activity of pure compounds (powder), showed that caffeic acid (IC50 = 4 μg/mL) had higher activity than p-coumaric acid (IC50 = 33 μg/mL). Films containing caffeic acid exhibited higher antioxidant activity, reducing power, and iron chelating ability than p-coumaric acid films. The antioxidant activity is concentration dependent. However, the percentage of release (PR) in ethanol (96%) is not influenced by the initial concentration. PR is 88% ± 9% and 82% ± 5%, respectively, for caffeic and p-coumaric acids. Determination of the partition ( Kp) and the apparent diffusion ( D) coefficients allowed better characterization of the release kinetic mechanisms. The partition coefficients of caffeic acid ( Kp = 454) and p-coumaric acid ( Kp = 480) are not influenced by the initial concentration. The diffusion coefficients ( D) of caffeic and p-coumaric acids were of same order, but they slightly increased with the antioxidant concentration and probably related to antioxidant activity. FTIR displayed that amide B and amide-III are involved in the interactions occurring between polymer chains and antioxidants. However, interactions are of only low energy and unable to significantly affect the structure of films and consequently the release kinetics.