Search results for "TRIZ"
showing 10 items of 343 documents
Synthesis of substituted piperidines by enantioselective desymmetrizing intramolecular aza-Michael reactions.
2018
An organocatalytic enantioselective intramolecular aza-Michael reaction has been described for the first time in a desymmetrization process employing substrates different from cyclohexadienones. By using 9-amino-9-deoxy-epi-hydroquinine as the catalyst and trifluoroacetic acid as a co-catalyst, a series of enantiomerically enriched 2,5-and 2,6-disubstituted piperidines have been obtained in good yields and with moderate diastereoselectivity. Depending on the catalyst/co-catalyst loading ratio, either the major or the minor diastereoisomer of the final piperidine products was achieved with high levels of enantioselectivity. Finally, some mechanistic insights have been considered by means of …
Asymmetric Synthesis of Spiro β-Lactamsviaa Squaramide- Catalyzed Sulfa-Michael Addition/Desymmetrization Protocol
2016
An efficient asymmetric synthesis of spirocyclohexenone β-lactams bearing three contiguous stereocenters has been achieved in moderate to good yields and high stereoselectivities. The protocol involves the combination of a squaramide-catalyzed sulfa-Michael addition under desymmetrization via a dynamic kinetic resolution of racemic 2,5-cyclohexadienones.
On the Dependence of Cirrus Parametrizations on the Cloud Origin
2019
<p>Particle size distributions (PSDs) for cirrus clouds are important for both climate models as well as many remote sensing retrieval methods. Therefore, PSD parametrizations are required. This study presents parametrizations of Arctic cirrus PSDs. The dataset used for this purpose originates from balloon-borne measurements carried out during winter above Kiruna (Sweden), i.e. north of the Arctic circle. The observations are sorted into two types of cirrus cloud origin, either in-situ or liquid. The cloud origin describes the formation pathway of the ice particles. At temperatures below −38 °C, ice particles form in-situ from solution or ice nuclea…
Improvement of Raw Milk Cheese Hygiene through the Selection of Starter and Non-Starter Lactic Acid Bacteria: The Successful Case of PDO Pecorino Sic…
2021
This review article focuses on the technological aspects and microbiological critical points of pressed-cooked cheeses processed from raw ewe’s milk without the inoculation of starter cultures, in particular “Pecorino” cheese typology produced in Italy. After showing the composition of the biofilms adhering to the surface of the traditional dairy equipment (mainly wooden vat used to collect milk) and the microbiological characteristics of PDO Pecorino Siciliano cheese manufactured throughout Sicily, this cheese is taken as a case study to develop a strategy to improve its hygienic and safety characteristics. Basically, the natural lactic acid bacterial populations of fresh and ripened chees…
Guidance for the risk assessment of the presence at low level of genetically modified plant material in imported food and feed under Regulation (EC) …
2017
Abstract This document provides guidance for the risk assessment under Regulation (EC) No 1829/2003 of the unintended, adventitious or technically unavoidable presence in food and feed of low level of genetically modified plant material intended for markets other than in the European Union. In this context, the presence at low level is defined to be maximum 0.9% of genetically modified plant material per ingredient. This guidance is intended to assist applicants by indicating which scientific requirements of Annex II of Regulation (EU) No 503/2013 are considered necessary for the risk assessment of the presence at low levels of genetically modified plant material in food and feed.
Anti-Listeria activity of lactic acid bacteria in two traditional Sicilian cheeses
2017
<em>Listeria monocytogenes</em> is a pathogen frequently found in dairy products, and its growth is difficult to control. Bacteriocinlike inhibitory substances (BLIS), produced by lactic acid bacteria (LAB), having proven <em>in vitro</em> anti-<em>Listeria</em> activity, could provide an innovative approach to control <em>L. monocytogenes</em>; however, this application needs to be evaluated <em>in vivo</em>. In this study, twenty LAB strains isolated from different Sicilian dairy environments were tested for control of growth of <em>L. monocytogenes</em> in three different experimental trials. First, raw and UHT milk …
Impact of packaging on the microbiological, physicochemical and sensory characteristics of a “pasta filata” cheese
2018
Abstract The present study evaluated the effects of four packaging technologies (vacuum, 2 types of modified atmosphere packaging [MAP1 = 70% N2/30% CO2; MAP2 = 100% N2] and paraffin) on the microbiological, chemical, physical and volatile organic composition, and the sensory characteristics of typical Sicilian stretched raw milk PDO (Protected Destination of Origin) Vastedda della Valle del Belice (VdB) cheese. The packaging applied did not affect the microbiological profiles of the cheeses. Of the chemical and physical parameters, only pH and water activity (aw) were statistically different among the trials. In particular, the cheeses wrapped in paraffin showed the highest pH value while …
Prickly Pear By-Product in the Feeding of Livestock Ruminants: Preliminary Investigation
2020
Simple Summary The question of sustainability of animal nutrition has become a popular topic. The gains made by recycling safe, yet otherwise valueless, by-products and wastes from human food and fiber production (green feeds) may lessen the competition between humans and animals for crops and decrease the environmental impact of food production. In this context, prickly pear by-product, which results from Opuntia ficus-indica (L.) Mill. fruits processed for juice extraction, could be an optimum by-product to ruminant feeding. This study evaluates the nutritional characteristics and its stability during storage using potassium metabisulfite as a preservative agent. This preliminary investig…
A large factory-scale application of selected autochthonous lactic acid bacteria for PDO Pecorino Siciliano cheese production
2016
The main hypothesis of this study was that the autochthonous lactic acid bacteria (LAB) selected for their dairy traits are able to stabilize the production of PDO (Protected Denomination of Origin) Pecorino Siciliano cheese, preserving its typicality. The experimental plan included the application of a multi-strain lactic acid bacteria (LAB) culture, composed of starter (Lactococcus lactis subsp. lactis CAG4 and CAG37) and non starter (Enterococcus faecalis PSL71, Lactococcus garviae PSL67 and Streptococcus macedonicus PSL72) strains, during the traditional production of cheese at large scale level in six factories located in different areas of Sicily. The cheese making processes were foll…
Effect of the inclusion of fresh lemon pulp in the diet of lactating ewes on the properties of milk and cheese
2017
This study investigated the effects of fresh lemon pulp (FLP), as a natural antioxidant in the diet, on the intake of feed and the production of milk and cheese of Valle del Belice lactating ewes during the hot summer in Sicily. A total of 15 second-lambing ewes, kept individually in 3 × 3 m pens, were divided into 3 homogeneous groups fed with 3 diets in a 3 × 3 Latin square design, with 3 experimental phases of 21 days each. The diets were: mixed hay ad libitum plus 600 g/day of concentrate (FLP0); mixed hay ad libitum plus 400 g/day of concentrate and 1 kg/day of FLP (FLP1); and mixed hay ad libitum plus 200 g/day of concentrate and 2 kg/day of FLP (FLP2). Nine experimental Pecorino chee…