Martina Lille

Bio: Martina Lille is an academic researcher from VTT Technical Research Centre of Finland. The author has contributed to research in topics: Food science & Chemistry. The author has an hindex of 23, co-authored 55 publications receiving 2254 citations.

Effect of high-pressure processing on colour, texture and flavour of fruit- and vegetable-based food products: a review

Abstract: Colour, flavour and texture are important quality characteristics of fruits and vegetables and major factors affecting sensory perception and consumer acceptance of foods. Various processing methods are used not only to increase the edibility and palatability of fruits and vegetables but also to prolong their shelf life. High-pressure (HP) processing is an interesting alternative to traditional food processing and preservation methods due to its limited effects on covalent bonds resulting in minimal modifications in nutritional and sensory quality. This review focuses specifically on the effects of HP treatment on colour, flavour and texture of fruit- and vegetable-based foods and tries to elucidate the mechanisms behind the observed changes in quality attributes. Possible impacts of HP treatments at elevated temperatures on these sensory properties are also highlighted since the temperature regime used for research on high pressure (HP) has been extended to elevated temperatures in order to achieve spore inactivation (e.g. HP sterilization).

Effect of enzyme-aided pressing on anthocyanin yield and profiles in bilberry and blackcurrant juices

Abstract: Bilberries (Vaccinium myrtillus) and blackcurrants (Ribes nigrum) were treated with extensive dosages of commercial cell wall degrading enzyme preparations, i.e. Econase CE, Pectinex Ultra SP-L, Pectinex Smash, Pectinex BE 3-L and Biopectinase CCM. The enzymes were dosed based on the polygalacturonase activity. The juice yield was improved in both berries as a result of the enzymatic treatment. The improvement was more pronounced with blackcurrants owing to their thicker cell walls. The impact of the enzymatic treatment on anthocyanins present in the juices was investigated using HPLC-DAD. The enzyme preparations affected the contents and composition of anthocyanins in the juices. Pectinex Ultra SP-L, Pectinex Smash, Pectinex BE 3-L and Biopectinase CCM increased the total content of anthocyanins by 13-41% in the bilberry juices and by 18-29% in the blackcurrant juices. Econase CE, however, produced a dramatic decrease in the total anthocyanin content in the bilberry juice due to its enzyme profile, whereas no such effect was observed with the blackcurrant juice. All the enzyme mixtures tested produced a total or extensive loss of anthocyanidin galactosides in bilberry juice. Commercial enzyme preparations used in the production of berry juices can improve extraction of anthocyanins into the juice. However, they may effectively hydrolyse certain glycosides and thus affect the profile of extracted anthocyanins.  2005 Society of Chemical Industry

The role of hemicellulose in nanofibrillated cellulose networks

Abstract: Cellulose nanofibrils show remarkable properties with applications in several fields of materials science, such as for composites, hydrogels, aerogels, foams, and coatings. Cellulose nanofibrils are typically produced by mechanical and enzymatic processing leading to fibrils having a width in the nanometer range and very high aspect ratios. The formation of percolating networks and interactions between fibrils lead to useful properties in for example gel formation and composites. In this work we studied how the residual xylan that is found in cellulose nanofibrils that have been produced from hardwood pulp affects these properties. We used enzymatic hydrolysis to specifically remove xylan and studied rheological properties, morphological features, and properties of paper-like films of cellulose nanofibrils. We found that removal of xylan enhances the formation of fibril networks, resulting in both stiffer gels and stronger films. However xylan also stabilizes the fibrils against flocculation. Also the history of processing of the preparations affects the results significantly.

Review of Hydrogels and Aerogels Containing Nanocellulose

Abstract: Naturally derived cellulose nanocrystals (CNCs) and cellulose nanofibrils (CNFs) are emerging nanomaterials that display high strength, high surface area, and tunable surface chemistry, allowing for controlled interactions with polymers, nanoparticles, small molecules, and biological materials. Industrial production of nanocelluloses is increasing rapidly with several companies already producing on the tons-per-day scale, intensifying the quest for viable products across many sectors. While the hydrophilicity of the nanocellulose interface has posed a challenge to the use of CNCs and CNFs as reinforcing agents in conventional plastics, it is a significant benefit for creating reinforced or structured hydrogel composites (or, when dried, aerogels) exhibiting both mechanical reinforcement and a host of other desirable properties. In this context, this Review describes the quickly growing field of hydrogels and aerogels incorporating nanocelluloses; over 200 references are summarized in comprehensive tables ...

A standardised static in vitro digestion method suitable for food – an international consensus

Abstract: Simulated gastro-intestinal digestion is widely employed in many fields of food and nutritional sciences, as conducting human trials are often costly, resource intensive, and ethically disputable. As a consequence, in vitro alternatives that determine endpoints such as the bioaccessibility of nutrients and non-nutrients or the digestibility of macronutrients (e.g. lipids, proteins and carbohydrates) are used for screening and building new hypotheses. Various digestion models have been proposed, often impeding the possibility to compare results across research teams. For example, a large variety of enzymes from different sources such as of porcine, rabbit or human origin have been used, differing in their activity and characterization. Differences in pH, mineral type, ionic strength and digestion time, which alter enzyme activity and other phenomena, may also considerably alter results. Other parameters such as the presence of phospholipids, individual enzymes such as gastric lipase and digestive emulsifiers vs. their mixtures (e.g. pancreatin and bile salts), and the ratio of food bolus to digestive fluids, have also been discussed at length. In the present consensus paper, within the COST Infogest network, we propose a general standardised and practical static digestion method based on physiologically relevant conditions that can be applied for various endpoints, which may be amended to accommodate further specific requirements. A frameset of parameters including the oral, gastric and small intestinal digestion are outlined and their relevance discussed in relation to available in vivo data and enzymes. This consensus paper will give a detailed protocol and a line-by-line, guidance, recommendations and justifications but also limitation of the proposed model. This harmonised static, in vitro digestion method for food should aid the production of more comparable data in the future.

Hydrogels for Biomedical Applications: Their Characteristics and the Mechanisms behind Them

Abstract: Hydrogels are hydrophilic, three-dimensional networks that are able to absorb large quantities of water or biological fluids, and thus have the potential to be used as prime candidates for biosensors, drug delivery vectors, and carriers or matrices for cells in tissue engineering. In this critical review article, advantages of the hydrogels that overcome the limitations from other types of biomaterials will be discussed. Hydrogels, depending on their chemical composition, are responsive to various stimuli including heating, pH, light, and chemicals. Two swelling mechanisms will be discussed to give a detailed understanding of how the structure parameters affect swelling properties, followed by the gelation mechanism and mesh size calculation. Hydrogels prepared from natural materials such as polysaccharides and polypeptides, along with different types of synthetic hydrogels from the recent reported literature, will be discussed in detail. Finally, attention will be given to biomedical applications of different kinds of hydrogels including cell culture, self-healing, and drug delivery.