Anton Slavov

Foaming and emulsifying properties of pectin isolated from different plant materials

Abstract The foaming and emulsifying properties of pectins obtained from waste rose petals, citrus pressings, grapefruit peels and celery were studied. It was found that the highest foaming capacity showed pectin derived from celery. The effect of pectin concentration on the foaming capacity of pectin solutions was investigated. For all the investigated pectins increasing the concentration led to increase of the foaming capacity. Emulsifying activity and emulsion stability of model emulsion systems (50 % oil phase) with 0.6 % pectic solutions were determined. The highest emulsifying activity and stability showed pectin isolated by dilute acid extraction from waste rose petals.

Effect of lavender (Lavandula angustifolia) and melissa (Melissa Officinalis) waste on quality and shelf life of bread

The effect of lavender (Lavandula angustifolia) and melissa (Melissa Officinalis) waste on preparation, characteristics and shelf life of bread was investigated. It was found that lavender and melissa waste, generated yearly in large amounts, were rich on polyphenols (especially rosmarinic acid) and aroma compounds, and exhibited high antioxidant and antimicrobial activity. The bread with 2.5% lavender waste was characterized with the highest loaf volume and loaf specific volume. The total dietary fiber increased three times and the polyphenols and flavonoids increased more than four times for breads with added 5% lavender and melissa waste, compared to control sample. The breads with 2.5% and 5% added lavender waste had increased shelf life (up to 96 h) compared to control, and no fungal or bacterial spoilage was observed during storage at 22 °C, 30 °C and 37 °C for four days. The sensory evaluation demonstrated that the consumers preferred mainly bread with 2.5% lavender waste.

Valorization of wastes from the rose oil industry

Every year, the rose oil industry generates large amounts of wastes due to the low content of essential oil in the fresh rose petals. Most of the distilleries simply discard the waste biomass which could lead to ecological problems in the nearby locations. Various methods for rose waste utilization have been successfully developed during the past years for the purpose of solving this problem. The aim of the present review is to summarize the possible approaches to the valorization of rose waste biomass, and to outline future trends. Apart from the common methods of disposal, i.e. composting, use for animal forage or simply discarding the wastes, there are several other promising and widely investigated strategies for utilization: aroma substance extraction, recovery of valuable biologically active substances and their application to food industry or medicine, and studies focused on increasing the essential oil yield. Novel approaches include the extraction of polysaccharides from the biomass and introduction of integrated methods for more complete valorization of the rose waste biomass. Nevertheless, most of the methods for rose waste valorization still remain on laboratory scale. This review shows that the potential of the rose oil industry wastes is still underexplored and further studies in this direction are needed.Graphical Abstract

Plant cell culture as emerging technology for production of active cosmetic ingredients

Plants have always been the main source for active cosmetic ingredients, having proven health beneficial effects on human, such as anti‐aging, antioxidant, anti‐inflammatory, UV‐protective, anti‐cancer, anti‐wrinkle, skin soothing, whitening, moisturizing, etc. Extracts from herbal, aromatic and/or medicinal plants have been widely used as effective active ingredients in cosmeceuticals or nutricosmetics, especially in products for topical application and skin‐care formulations. However, over the past decade, there has been an increasing interest to plant cell culture – derived active cosmetic ingredients. These are “new generation” of high quality natural products, produced by the modern plan biotechnology methods, which usually showed stronger activities than the plant extracts obtained by the classical methods. In this review, the advantages and the current progress in plant cell culture technology for the production of active cosmetic ingredients have been summarized, and discussed in details within a presented case study for calendula stem cell product development.

Effects on the quality and health-enhancing properties of industrial onion waste powder on bread

Industrial onion waste powder (IOWP) was used as an additive in wheat flour at different levels: 0, 1, 2, 3, 4 and 5%. The effect of onion waste addition on the mixing properties of the dough and quality of bread was investigated. The mixing properties of the dough were determined by farinograph. The bread were characterized and evaluated for crumb hardness, crumb porosity, sensory properties, dietary fiber, total phenolic content and total flavonoids. DPPH and FRAP assays were carried out to measure antioxidant activity in vitro. The results indicated that IOWP could be used as a potential health-enhancing functional ingredient up to 3% level to produce bread enriched with dietary fiber, total phenolic compounds and total flavonoids, and characterized by high antioxidant activity and acceptable quality.