TY - JOUR A1 - Borremans, An A1 - Bußler, Sara A1 - Sagu Tchewonpi, Sorel A1 - Rawel, Harshadrai Manilal A1 - Schlüter, Oliver K. A1 - Leen, Van Campenhout T1 - Effect of blanching plus fermentation on selected functional properties of mealworm (Tenebrio molitor) powders JF - Foods : open access journal N2 - The aim of this study was to determine the effect of blanching followed by fermentation of mealworms (Tenebrio molitor) with commercial meat starter cultures on the functional properties of powders produced from the larvae. Full fat and defatted powder samples were prepared from non-fermented and fermented mealworm pastes. Then the crude protein, crude fat, and dry matter contents, pH, bulk density, colour, water and oil binding capacity, foaming capacity and stability, emulsion capacity and stability, protein solubility, quantity of free amino groups, and protein composition of the powders were evaluated. Regardless of the starter culture used, the blanching plus fermentation process reduced the crude and soluble protein contents of the full fat powders and in general impaired their water and oil binding, foaming, and emulsifying properties. Defatting of the powders improved most functional properties studied. The o-phthaldialdehyde assay revealed that the amount of free amino groups was higher in the fermented powders while sodium dodecyl sulfate polyacrylamide gel electrophoresis demonstrated that the soluble proteins of the fermented powders were composed of molecules of lower molecular mass compared to non-fermented powders. As molecular sizes of the soluble proteins decreased, it was clear that the protein structure was also modified by the fermentation process, which in turn led to changes in functional properties. In general, it was concluded that fermentation of mealworms with blanching as a pre-treatment does not contribute to the functional properties studied in this work. Nevertheless, the results confirmed that the properties of non-fermented powders are comparable to other food protein sources. KW - mealworm KW - fermentation KW - functional properties KW - insect proteins KW - SDS-PAGE Y1 - 2020 U6 - https://doi.org/10.3390/foods9070917 SN - 2304-8158 VL - 9 IS - 7 PB - MDPI CY - Basel ER - TY - JOUR A1 - Bußler, Sara A1 - Rawel, Harshadrai Manilal A1 - Schlüter, Oliver K. T1 - Impact of plasma processed air (PPA) on phenolic model systems BT - suggested mechanisms and relevance for food applications JF - Innovative food science & emerging technologies : the official journal of the European Federation of Food Science and Technology N2 - Cold plasma is considered to be a novel, non-thermal, chemical-free and eco-friendly disinfection and surface modification technology. Plasma treatment of air to generate the so called plasma processed air (PPA) induces the formation of reactive oxygen (ROS) and nitrogen species (RNS). As a result, PPA has a different chemical composition compared to untreated air and suits therefore as an alternative method for microbial disinfection. However, depending on the product properties of the food matrix and its composition, a number of plasmainduced reactions also need to be taken into consideration. This necessitates also the elucidation and understanding of the basic interactions of plasma species with bioactive compounds. The intention here is to avoid the degradation of these valuable substances and to prevent other undesirable effects in future food related applications. In the present study, the effects of PPA treatment on selected antioxidants such as pyrocatechol and derivatives of hydroxycinnimic acid were investigated in model systems to specify possible reactions induced. Antioxidant capacity, pH value, UV-Vis spectroscopy, RP-HPLC and LC-MS analysis were applied to identify reaction products providing information on possible changes induced in food matrices by PPA treatment. Exposure to PPA caused a perceptible color change towards yellow-brown accompanied by a strong reduction of the pH and the formation of insoluble sediments in the model solutions. The accumulation of nitrate, nitrite, but not of hydrogen peroxide was shown. LC-MS analysis demonstrated the formation of plasma-modified derivatives in all tested systems. The main reactions in liquid model solutions exposed to PPA were attributed to oxidation, nitration and polymerization of the phenolic compounds. KW - cold atmospheric pressure plasma KW - reactive oxygen and nitrogen species KW - food safety KW - antioxidative phenolic ingredients KW - phenol oxidation KW - phenol nitration KW - plasma process indicators Y1 - 2020 U6 - https://doi.org/10.1016/j.ifset.2020.102432 SN - 1466-8564 SN - 1878-5522 VL - 64 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Bußler, Sara A1 - Rumpold, Birgit A. A1 - Fröhling, Antje A1 - Jander, Elisabeth A1 - Rawel, Harshadrai Manilal A1 - Schlüter, Oliver K. T1 - Cold atmospheric pressure plasma processing of insect flour from Tenebrio molitor: Impact on microbial load and quality attributes in comparison to dry heat treatment JF - Meteoritics & planetary science : journal of the Meteoritical Society N2 - In this study, the applicability of semi-direct cold atmospheric pressure plasma (CAPP) during postharvest processing of Tenebrio molitor flour is investigated. Besides analyzing the decontamination efficacy, plasma induced impact on techno-functionality, protein solubility, composition and structure was determined and compared to heat induced effects. Following CAPP treatment, the total microbial load of the Tenebrio flour of 7.72 log(10) cfu/g was reduced to 7.10 (1 min), 6.72 (2.5 min), 5.79 (5 min), 5.19 (7.5 min), 521 (10 min) and 4.73 (15 min) log(10) cfu/g. With increasing exposure to CAPP, protein solubility at pH 4 almost linearly decreased to a minimum of 54%. Water binding capacity decreased from 0.79 to 0.64 gwatedg whereas oil binding capacity increased from 0.59 to 0.66 g(oil)/g. Gel electrophoresis revealed a decrease of all protein fractions at pH 4 whereas at pH 10 the band pattern significantly shifted to protein fractions with higher molecular weights. Industrial relevance: Edible insects are rich in valuable protein, fat, fibre, minerals and micronutrients. Although a wide range of species represent a valuable alternative protein source that could contribute to food and feed security, they are industrially hardly exploited. The tailored application of proper processing technologies could lead to novel insect-based high-protein food and feed products with unique functional properties supporting the increase in acceptability among potential consumers. Current research concentrates on developing processing chains including innovative nonthermal approaches. Cold atmospheric pressure plasma (CAPP) has gained attention as an effective technology for the decontamination and modification of fresh and dry agricultural products. In the postharvest chain of edible insects, the application of CAPP could contribute to the development of safe and high-quality insect-based products in the food and feed sector. (C) 2016 Published by Elsevier Ltd. KW - Edible insects KW - Postharvest processing KW - Thermal and nonthermal treatment KW - Inactivation KW - Decontamination KW - Protein functionality and modification Y1 - 2016 U6 - https://doi.org/10.1016/j.ifset.2016.07.002 SN - 1466-8564 SN - 1878-5522 VL - 36 SP - 277 EP - 286 PB - Elsevier CY - Oxford ER - TY - JOUR A1 - Tchewonpi Sagu, Sorel A1 - Landgräber, Eva A1 - Henkel, Ina M. A1 - Huschek, Gerd A1 - Homann, Thomas A1 - Bußler, Sara A1 - Schlüter, Oliver K. A1 - Rawel, Harshadrai Manilal T1 - Effect of cereal α-amylase/trypsin inhibitors on developmental characteristics and abundance of digestive enzymes of mealworm larvae (Tenebrio molitor L.) JF - Insects N2 - The objective of this work was to investigate the potential effect of cereal α-amylase/trypsin inhibitors (ATIs) on growth parameters and selective digestive enzymes of Tenebrio molitor L. larvae. The approach consisted of feeding the larvae with wheat, sorghum and rice meals containing different levels and composition of α-amylase/trypsin inhibitors. The developmental and biochemical characteristics of the larvae were assessed over feeding periods of 5 h, 5 days and 10 days, and the relative abundance of α-amylase and selected proteases in larvae were determined using liquid chromatography tandem mass spectrometry. Overall, weight gains ranged from 21% to 42% after five days of feeding. The larval death rate significantly increased in all groups after 10 days of feeding (p < 0.05), whereas the pupation rate was about 25% among larvae fed with rice (Oryza sativa L.) and Siyazan/Esperya wheat meals, and only 8% and 14% among those fed with Damougari and S35 sorghum meals. As determined using the Lowry method, the protein contents of the sodium phosphate extracts ranged from 7.80 ± 0.09 to 9.42 ± 0.19 mg/mL and those of the ammonium bicarbonate/urea reached 19.78 ± 0.16 to 37.47 ± 1.38 mg/mL. The total protein contents of the larvae according to the Kjeldahl method ranged from 44.0 and 49.9 g/100 g. The relative abundance of α-amylase, CLIP domain-containing serine protease, modular serine protease zymogen and C1 family cathepsin significantly decreased in the larvae, whereas dipeptidylpeptidase I and chymotrypsin increased within the first hours after feeding (p < 0.05). Trypsin content was found to be constant independently of time or feed material. Finally, based on the results we obtained, it was difficult to substantively draw conclusions on the likely effects of meal ATI composition on larval developmental characteristics, but their effects on the digestive enzyme expression remain relevant. KW - growth behavior KW - Tenebrio molitor larvae KW - feeding KW - cereal meals KW - α-amylase/trypsin inhibitors KW - digestive enzymes quantification KW - LC-MS/MS Y1 - 2021 U6 - https://doi.org/10.3390/insects12050454 SN - 2075-4450 VL - 12 IS - 5 PB - MDPI CY - Basel ER - TY - GEN A1 - Tchewonpi Sagu, Sorel A1 - Landgräber, Eva A1 - Henkel, Ina M. A1 - Huschek, Gerd A1 - Homann, Thomas A1 - Bußler, Sara A1 - Schlüter, Oliver K. A1 - Rawel, Harshadrai Manilal T1 - Effect of cereal α-amylase/trypsin inhibitors on developmental characteristics and abundance of digestive enzymes of mealworm larvae (Tenebrio molitor L.) T2 - Postprints der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe N2 - The objective of this work was to investigate the potential effect of cereal α-amylase/trypsin inhibitors (ATIs) on growth parameters and selective digestive enzymes of Tenebrio molitor L. larvae. The approach consisted of feeding the larvae with wheat, sorghum and rice meals containing different levels and composition of α-amylase/trypsin inhibitors. The developmental and biochemical characteristics of the larvae were assessed over feeding periods of 5 h, 5 days and 10 days, and the relative abundance of α-amylase and selected proteases in larvae were determined using liquid chromatography tandem mass spectrometry. Overall, weight gains ranged from 21% to 42% after five days of feeding. The larval death rate significantly increased in all groups after 10 days of feeding (p < 0.05), whereas the pupation rate was about 25% among larvae fed with rice (Oryza sativa L.) and Siyazan/Esperya wheat meals, and only 8% and 14% among those fed with Damougari and S35 sorghum meals. As determined using the Lowry method, the protein contents of the sodium phosphate extracts ranged from 7.80 ± 0.09 to 9.42 ± 0.19 mg/mL and those of the ammonium bicarbonate/urea reached 19.78 ± 0.16 to 37.47 ± 1.38 mg/mL. The total protein contents of the larvae according to the Kjeldahl method ranged from 44.0 and 49.9 g/100 g. The relative abundance of α-amylase, CLIP domain-containing serine protease, modular serine protease zymogen and C1 family cathepsin significantly decreased in the larvae, whereas dipeptidylpeptidase I and chymotrypsin increased within the first hours after feeding (p < 0.05). Trypsin content was found to be constant independently of time or feed material. Finally, based on the results we obtained, it was difficult to substantively draw conclusions on the likely effects of meal ATI composition on larval developmental characteristics, but their effects on the digestive enzyme expression remain relevant. T3 - Zweitveröffentlichungen der Universität Potsdam : Mathematisch-Naturwissenschaftliche Reihe - 1153 KW - growth behavior KW - Tenebrio molitor larvae KW - feeding KW - cereal meals KW - α-amylase/trypsin inhibitors KW - digestive enzymes quantification KW - LC-MS/MS Y1 - 2021 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:kobv:517-opus4-520924 SN - 1866-8372 IS - 5 ER -