Encapsulation and fish dominate July's science
innovation. The highlights of this month's science have been novel
encapsulation and controlled release, and getting more from fish.
Controlled release The controlled release of ingredients, from flavours to nutrients, has been receiving more research attention. However, according to Dérick Rousseau, PhD, from Ryerson University in Canada, few examples, if any, of food-related commercial applications of controlled release exist. Dr Rousseau told attendees at the IFT International Food Nanoscience Conference in New Orleans that while the science is coming along, the understanding of controlled release of ingredients for food is still full of holes. "When it comes to foods and the concept and application of controlled release, what we do know is dwarfed by what we don't," he said. There are options available to food scientists however, and Dr Rousseau has his finger in a lot of research pies, being active in the study of many different types of controlled release. These include microemulsions containing nano-scale particles, self-assembled dairy proteins, and phase-separated hydrogels. He said that micro emulsions offer the easiest application, and they are thermodynamically stable, meaning they are formed almost instantly on mixing, and they also do not separate over time. But it's not all plain-sailing, and innovation is handicapped by the limited choice of food grade surfactants. On the topic of self-assembling proteins, Dr Rousseau told FoodNavigator this was "intriguing." Indeed, fellow IFT speaker Kees de Kruif from NIZO Food Research in the Netherlands told this website that, while the majority of research in this area to date has focussed on dairy proteins, the field could be expanded to non-dairy proteins, in principle. "Self-assembling of proteins is common. In fact, it's more of a rule than an exception. If we can manipulate this self-assembling of proteins at the nanoscale, I see a big future for it," he said. Fishy alternatives Recent food safety fears such as BSE in cattle and avian 'flu in poultry prompted consumers and marketers to look for products containing no animal derivatives, and this is affecting ingredients like gelatine. Despite certain companies and institutions claiming to have conclusively proven that there is no link between gelatine and BSE, this has not stopped the search for alternatives. Researchers from Malaysia reported earlier this month that fish gelatine (especially from warm water fish) "possesses similar characteristics to porcine gelatine and may thus be considered as an alternative to mammalian gelatine for use in food products." Gelatine is a translucent colourless substance, created by prolonged boiling of animal skin, connective tissue or bones. It is most commonly used as a stabiliser, thickener, or texturiser in foods such as ice cream, jams and yoghurt, and is also used to improve the mouthfeel of various products. "Production and utilization of fish gelatine not only satisfies the needs of consumers, but also serves as a means to utilise some of the byproducts of the fishing industry," they wrote in the journal Food Hydrocolloids. In a different study, researchers from Mexico reported that protein hydrolysates from Pacific whiting, an abundant and under-utilised fish, could substitute functional compounds such as bovine serum albumin and sodium caseinate. "Results in the present study showed that hydrolysates produced from Pacific whiting (Merluccius productus) muscle can be used as food ingredients or additives to impart a desire characteristic to food products or increase food storage stability, acting as emulsifying, foaming or dispersing agents, in sausages, mayonnaise, salad dressings, beverages, creams, etc., all these in a broad pH range," they in the journal Food Chemistry.