The bioavailability of zinc is closely related to its existing form. In this study, the effects of thermal processing on the existing form of zinc in oysters was explored. Three thermal processing methods, steamed (100 ℃, 10 min), fried (140 ℃, 5 min) and grilled (200 ℃, 15 min), had been applied on oysters to study the total zinc and zinc ions changes in content, zinc content in polysaccharides and proteins, respectively. Fourier infrared spectrometer was employed to determine the structural changes of polysaccharides and proteins in oysters. The results showed that with the treatment of the steaming and frying process, the total zinc content of oysters was significantly reduced by 6.43% and 14.68%, and the zinc ion content decreased by 45.60% and 68.12%. During the roasting process, the total zinc content had no significant difference. But the zinc ion content decreased by 50.59%, the significant reduction was found in fried group. On the other hand, the thermal processing methods had been significantly reduced the zinc-binding capacity of polysaccharides and proteins in the oysters. The infrared spectroscopy showed that the functional groups and chemical bonds of the polysaccharides were not significantly changed, however, the secondary structures of the proteins were changed. In current study, the results showed that the thermal processing methods cause the loss of zinc in oysters accompanied with the loss of fluid, and the ionic form of zinc was the major one. These processing methods change the structures of polysaccharides and proteins, which might also destroy the binding mode of zinc with polysaccharides and proteins.
[1] HARA T,TAKEDA T,TAKAGISHI T,et al.Physiological roles of zinc transporters:Molecular and genetic importance in zinc homeostasis[J].Physiological Sciences,2017,67(2):283-301.
[2] MATTHEWS J M,BHATI M,LEHTOMAKI E,et al.It Takes two to tango:The structure and function of LIM,RING,PHD and MYND domains[J].Current Pharmaceutical Design,2009,15(31):3 681-3 696.
[3] MARET W,SANDSTEAD H H.Zinc requirements and the risks and benefits of zinc supplementation[J].Journal of Trace Elements in Medicine and Biology,2006,20(1):3-18.
[4] TOSHIYUKI F,SATORU Y,KEIGO N,et al.Zinc homeostasis and signaling in health and diseases:Zinc signaling[J].Journal of Biological Inorganic Chemistry,2011,16(7):1 123-1 134.
[5] PRASAD A S.Zinc:An overview[J].Nutrition,1995,11(1):93-99.
[6] PRASAD A S.Discovery of human zinc deficiency:Its impact on human health and disease[J].Advances in Nutrition,2013,4(2):176-190.
[7] 韩蓉,曹文红,章超桦,等.香港牡蛎中锌元素的分布及存在形态[J].广东海洋大学学报,2021,41(4):1-8.
HAN R,CAO W H,ZHANG C H,et al.Distribution and existential forms of zinc in Crassostrea hongkongensis[J].Journal of Guangdong Ocean University,2021,41(4):1-8.
[8] ZHANG S Q,YU X F,ZHANG H B,et al.Comparison of the oral absorption,distribution,excretion,and bioavailability of zinc sulfate,zinc gluconate,and zinc-enriched yeast in rats[J].Molecular Nutrition & Food Research,2018,62(7):e1700981.
[9] 汪婧瑜,张业辉,张友胜,等.不同结构的乌鳢螯合肽对抗氧化活性的影响[J].中国食品学报,2019,19(10):93-99.
WANG J Y,ZHANG Y H,ZHANG Y S,et al.The effect of different structure of chelated peptides of Channa argus on antioxidant activity[J].Journal of Chinese Institute of Food Science and Technology,2019,19(10):93-99.
[10] 杨月欣,王光亚,潘兴吕.中国食物成分表[M].北京:北京大学医学出版社,2010.
YANG Y X,WANG G Y,PAN X L.China Food Composition Table[M].Beijing:Peking University Medical Press,2010.
[11] DOMINGO J L.Influence of cooking processes on the concentrations of toxic metals and various organic environmental pollutants in food:A review of the published literature[J].Critical Reviews in Food Science and Nutrition,2011,51(1):29-37.
[12] BILANDZIC N,SEDAK M,DOKIC M,et al.Determination of zinc concentrations in foods of animal origin,fish and shellfish from Croatia and assessment of their contribution to dietary intake[J].Journal of Food Composition and Analysis,2014,35(2):61-66.
[13] HOSSEINI H,MAHMOUDZADEH M,REZAEI M,et al.Effect of different cooking methods on minerals,vitamins and nutritional quality indices of kutum roach(Rutilus frisii Kutum)[J].Food Chemistry,2014,148:86-91.
[14] MNARI B A,ZAGHBIB S F,DHIBI M,et al.Effects of different cooking methods on the mineral contents of wild and farmed sea bream(Sparus aurata)[J].International Journal of Food Science and Technology,2012,47(9):1 964-1 969.
[15] MEI H,WANG W X.Bioaccessibility of 12 trace elements in marine mollusks[J].Food and Chemical Toxicology,2013,55:627-636.
[16] ELIYAS N,XIAO H X,ZHANG Y,et al.Effects of different temperatures on the chemical structure and antitumor activities of polysaccharides from Cordyceps militaris[J].Polymers,2018,10(4):430.
[17] LI X Q,LIU A J.Relationship between heat treatment on structural properties and antitumor activity of the cold-water soluble polysaccharides from Grifola frondosa[J].Glycoconjugate Journal,2020,37(1):107-117.
[18] 郭子璇,陈慧,王震宇,等.热处理对牡蛎蛋白结构及功能特性的影响[J].大连工业大学学报,2020,39(4):235-240.
GUO Z X,CHEN H,WANG Z Y,et al.Effect of heat treatment on the structure and functional properties of oyster protein[J].Journal of Dalian Polytechnic University,2020,39(4):235-240.
[19] CHEN D,LIU Z Y,HUANG W Q,et al.Purification and characterization of a zinc-binding peptide from oyster protein hydrolysate[J].Journal of Functional Foods,2013,5(2):689-697.
[20] BELICIU C M,MORARU C I.Physico-chemical changes in heat treated micellar casein-soy protein mixtures[J].LWT-Food Science and Technology,2013,54(2):469-476.
[21] LI H,TAN X Y,XIA X Y,et al.Thermal treatment modified the physicochemical properties of recombinant oyster(Crassostrea gigas) ferritin[J].Food Chemistry,2020,314:126 210.
[22] ZHANG J Q,LI C,HUANG Q,et al.Comparative study on the physicochemical properties and bioactivities of polysaccharide fractions extracted from Fructus mori at different temperatures[J].Food & Function,2019,10:410-421.
[23] BARTH A,HARIS P I,WEERT M V D,et al.Infrared Spectroscopy of Protein Pharmaceuticals[M].Clifton:IOS Press,2009.
[24] LONG G H,JI Y,PAN H B,et al.Characterization of thermal denaturation structure and morphology of soy glycinin by FTIR and SEM[J].International Journal of Food Properties,2015,18(4):763-774.
[25] LEE H J,CHOI C,LEE S.Membrane-bound alpha-synuclein has a high aggregation propensity and the ability to seed the aggregation of the cytosolic form[J].The Journal of Biological Chemistry,2002,277(1):671-678.
[26] MICHAEL J,HENRY H M.Conformation of the peptide hormone somatostatin in aqueous solution and organic solvents[J].Vibrational Spectroscopy,1992,3(4):323-326.
[27] CAO Y G,XIONG Y L.Chlorogenic acid-mediated gel formation of oxidatively stressed myofibrillar protein[J].Food Chemistry,2015,180:235-243.
