Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, es...Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, especially those in Western countries who are used to peaceful flavor, has been limited due to the adverse flavor impact brought by its special composition. In recent years, with the increasing attention to the nutritional value of soymilk, the flavor of soymilk has become a popular research object for scholars at home and abroad. The flavor components of soymilk are mainly volatile small molecular compounds produced by enzymatic reactions catalyzed by lipoxygenase(LOX). After formation, they interact with protein macromolecules to form the overall flavor of soymilk. At present, there are many methods to control the off-odor of soymilk at home and abroad, including physical heating methods, chemical methods, biological enzymatic digestion methods, mask methods, and a variety of breeding methods. These methods effectively reduce the off-odor of soymilk, but all of them have shortcomings. Currently, the sensory characteristics of the beany odor in soymilk are evaluated mainly by traditional human sensory scoring along with the assistance of modern instrument analysis of volatile flavor substances using headspace solid phase microextraction(SPME) gas chromatography coupled with-mass spectrometry(GC-MS). This paper summarized the research results of volatile flavor substances in soymilk in recent years and the sensory evaluation methods of soymilk at home and abroad, and looked forward to the future development direction, hoping to provide some theoretical bases and reference detection methods for solving the problem of soymilk flavor in the future.展开更多
Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South Chin...Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients.展开更多
An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cros...An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cross section. The corrosion mechanisms, cases ofant's nest corrosion, and preventive measures are presented.展开更多
Simultaneous distillation-extractor was used for extracting the volatile substances in Llex Kudincha.26 volatile components were identified by gas chromatography mass spectrometry (GC-MS)method.The identified compound...Simultaneous distillation-extractor was used for extracting the volatile substances in Llex Kudincha.26 volatile components were identified by gas chromatography mass spectrometry (GC-MS)method.The identified compounds are 94.83 % of the total volatile substances.展开更多
[Objective] The aim was to provide theoretical basis for the exploitation and utilization of Trifolium. [Method] This paper introduced the main active ingredients,pharmacological effects and applications of Trifolium,...[Objective] The aim was to provide theoretical basis for the exploitation and utilization of Trifolium. [Method] This paper introduced the main active ingredients,pharmacological effects and applications of Trifolium, and looked into research focus and direction in the future. [ Result] The main active ingredient of Trifolium is leaves protein concentration, isoflavones, chlorogenic acid and volatile substance. [ Conclusion] Trifolium resources in our country is abundant, which has been thought to be the most potential health food and new medical resources. It becomes research hotspot in the field of health food, biological medicine and related fields with its biological functions and pharmacological effects. We should strength- en the exploitation and utilization of Trifolium active ingredients apart from its forage function.展开更多
Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and USA.Practices such as using blends of...Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and USA.Practices such as using blends of different species and adding low-cost raw materials,such as chicory,corn,and soybean,impair the sensory and functional characteristics of the drink made from roasted and ground coffee beans.There is a need to adopt more efficient analytical methods than the microscopy technique currently used.The first chromatographic method used to determine fraud was reported in 1958.This method used paper chromatography to differentiate between coffee and chicory based on the free reducing sugars.As of the 1980s,different methods involving high-performance liquid chromatography and gas chromatography were developed in order to demonstrate geographic authenticity,distinction between species,occurrence of adulteration,and the presence of defective beans by determining the monosaccharides,oligosaccharides,tocopherols,fatty acids,volatiles,diterpenes,sterols,and phenolic substances,among others.As far as the authors know,there are no papers published in the literature that have compiled such an extensive set of information about these chromatographic methods as here.Over the last 2 years,there has been a trend to develop analytical methods for ultra-performance liquid chromatography coupled with tandem mass spectrometry to confirm fraud in coffee,due to high sensitivity and selectivity.展开更多
基金Supported by the Youth Fund Project of the National Natural Science Foundation of China(32001570)the Post-doctorate Program Funding in Heilongjiang Province(LBH-Z19118)the Academic Backbone'Project of Northeast Agricultural University(20XG11)。
文摘Soybean is one of the important crops in China. Soymilk, a traditional neutral plant-based protein drink, is rich in high quality proteins. Although soybean milk is rich in nutrients, its marketing among consumers, especially those in Western countries who are used to peaceful flavor, has been limited due to the adverse flavor impact brought by its special composition. In recent years, with the increasing attention to the nutritional value of soymilk, the flavor of soymilk has become a popular research object for scholars at home and abroad. The flavor components of soymilk are mainly volatile small molecular compounds produced by enzymatic reactions catalyzed by lipoxygenase(LOX). After formation, they interact with protein macromolecules to form the overall flavor of soymilk. At present, there are many methods to control the off-odor of soymilk at home and abroad, including physical heating methods, chemical methods, biological enzymatic digestion methods, mask methods, and a variety of breeding methods. These methods effectively reduce the off-odor of soymilk, but all of them have shortcomings. Currently, the sensory characteristics of the beany odor in soymilk are evaluated mainly by traditional human sensory scoring along with the assistance of modern instrument analysis of volatile flavor substances using headspace solid phase microextraction(SPME) gas chromatography coupled with-mass spectrometry(GC-MS). This paper summarized the research results of volatile flavor substances in soymilk in recent years and the sensory evaluation methods of soymilk at home and abroad, and looked forward to the future development direction, hoping to provide some theoretical bases and reference detection methods for solving the problem of soymilk flavor in the future.
基金supported by the earmarked fund for the Modern Agro-Industry Technology Research System (No. CARS-49)the Natural Science Foundation of Shan-dong Province (No. ZR2018BC052)+1 种基金the Entrepreneurship and Innovation Talents programme of Jiangsu Province of China (2020–2023)the Huaguo Mountain Talent Pro-gramme of Lianyungang City Jiangsu Province (2019–2022)。
文摘Cephalopods are important economic shellfish that have been developed extensively in the coastal water of various countries. Octopus vulgaris is a large-scaled economic cephalopod that is mainly cultured in South China. This study explored the effect of different diets on the volatile flavor and nutritional ingredients of O. vulgaris. Four diets were tested in four groups: Group A(fish(Scomberomorus niphonius)), Group B(crab(Helice tridens tientsinensis Rathbun)), Group C(clam(Mactra veneriformis)), and Group D(squid(Loligo japonica)). Octopus muscles were sampled after 36 days of feeding, and volatile flavor substances(VFSs), fatty acids(FAs), and amino acids(AAs) were detected. Results showed that the VFSs, FAs, and AAs of octopus in the four groups were obviously different. The sum of volatile ketones and aldehydes was higher in Group B than in the other groups, which could present much more flavors. All groups were abundant in unsaturated FAs, including eicosapentaenoic acid(EPA) and docosahexaenoic acid(DHA). In terms of content and variety, the FAs in Group B were more beneficial to human health than those in the other groups. The content of each AA in Group B was basically higher than those in the other groups and was significantly higher than that in Group D(P < 0.05). Comparing the VFSs, FAs, and AAs in samples fed with four kinds of diets, the results indicate that using crab to feed O. vulgaris can achieve better effects on volatile flavor and nutritional ingredients.
文摘An unusual form of localized corrsion in copper tubes was detected early in service and in leakage tests after manufacturing.The morphology of this corrosion is similar to that of an ant's nest when viewed in cross section. The corrosion mechanisms, cases ofant's nest corrosion, and preventive measures are presented.
文摘Simultaneous distillation-extractor was used for extracting the volatile substances in Llex Kudincha.26 volatile components were identified by gas chromatography mass spectrometry (GC-MS)method.The identified compounds are 94.83 % of the total volatile substances.
基金funded by the national science and technology support plan ( 2011BAD17B03):Research and integrated demonstration of efficient production and utilization high quality forage of three gorges reservoir area
文摘[Objective] The aim was to provide theoretical basis for the exploitation and utilization of Trifolium. [Method] This paper introduced the main active ingredients,pharmacological effects and applications of Trifolium, and looked into research focus and direction in the future. [ Result] The main active ingredient of Trifolium is leaves protein concentration, isoflavones, chlorogenic acid and volatile substance. [ Conclusion] Trifolium resources in our country is abundant, which has been thought to be the most potential health food and new medical resources. It becomes research hotspot in the field of health food, biological medicine and related fields with its biological functions and pharmacological effects. We should strength- en the exploitation and utilization of Trifolium active ingredients apart from its forage function.
基金Universidade Federal Rural do Rio de Janeiro(UFRRJ),Empresa Brasileira de Pesquisa Agropecuária(Embrapa)and Coordenação de Aperfeiçoamento de Pessoal de Nível Superior(CAPES)for their financial support(1020010/00542).
文摘Coffee is currently the second largest commodity on the world market today,and there is great concern about the quality of the beans exported from producer countries to Europe and USA.Practices such as using blends of different species and adding low-cost raw materials,such as chicory,corn,and soybean,impair the sensory and functional characteristics of the drink made from roasted and ground coffee beans.There is a need to adopt more efficient analytical methods than the microscopy technique currently used.The first chromatographic method used to determine fraud was reported in 1958.This method used paper chromatography to differentiate between coffee and chicory based on the free reducing sugars.As of the 1980s,different methods involving high-performance liquid chromatography and gas chromatography were developed in order to demonstrate geographic authenticity,distinction between species,occurrence of adulteration,and the presence of defective beans by determining the monosaccharides,oligosaccharides,tocopherols,fatty acids,volatiles,diterpenes,sterols,and phenolic substances,among others.As far as the authors know,there are no papers published in the literature that have compiled such an extensive set of information about these chromatographic methods as here.Over the last 2 years,there has been a trend to develop analytical methods for ultra-performance liquid chromatography coupled with tandem mass spectrometry to confirm fraud in coffee,due to high sensitivity and selectivity.