Studies On The Development Of Oat Bran Pork Meatballs And The Effects Of Cooking.Storaging And Reheating To Its Qualities

Pork meatball is a kind of traditional meat products which has a long history in China.It consists of lean and fat meat according to the ratio of three to seven.It is welcomed by local residents because of its delicate,juicy,refreshing,flexible and strong fragrance.However,with the improvement of people's health consciousness,low fat,high fiber and high protein products were loved by people.Additionally,the influence of cooking,storage and reheat methods to meatballs were also concerned by people.Oat bran has good coherence and high fiber,it is the best substitution to instead part of fat so as to make the pork meatball more healthily.Firstly,explored the influence of different oat bran addition on the quality of pork meatballs.Secondly,did some research to exploit new meatballs.Thirdly,explored the effects of four domestic cooking methods on the sensory characteristics,nutrition,and flavor of oat bran pork meatballs.Fourthly,explored the influence of different storage temperature and time on boiled meatballs.Finally,explored the effects of four domestic reheating methods on frozen boiled samples.The main results were as follows:1.Effects of Oat Bran Content to the Quality of Oat Bran Pork MeatballsIn order to develop the best low-fat meatballs with oat bran replacing the fat,the paper studied the influence of different oat bran content to traditional pork meatballs'quality which included sensory quality,color,texture,basic composition(moisture,fat,crude protein and crude fiber content),flavor(volatile and non volatile flavor compounds)and oxidation(POV and TBA values)so as to provide feasible suggestions for the development of low-fat oat bran pork meatballs.The results show that when the oat bran content of total material quality was 3.09%,the samples had the highest sensory evaluation.With the increase of oat bran,the hardness,chewiness reduced significantly,stretch and recovery had no difference;brightness decreased gradually,redness and yellowness increased;fat content decreased significantly,oat bran and protein content increased apparently,moisture content increased slightly.According to the electronic nose and GC-MS analysis,the flavor of five samples can be distinguished significantly and fat oxidation products were decreased gradually.The HPLC analysis indicated that the content of oat bran had no effect to nucleotide almostly,but total amino acids decreased significantly.Therefore,the oat bran content had a large effect to the products.In addition,with the increase of the content of oat bran,the POV value decreased gradually,but the TBA value was increased.In summary,the oat bran content had different influence to different quality of pork meatballs.Therefore,the appropriate oat bran addition(3.09%)can ensure the comprehensive quality of the product is the best.2.The best addition amount of some key materials in oat bran pork meatballsChoose oat bran,protein separated from soybean and the compound phosphate as the key ingredients in the orthogonal experiment to make sure the best addition amount in meatballs after the preview experiments of single factor.Select four better groups to go on other experiences such as structure,color,luster and drainage rate,basic composition and the oxidation degree analysis according to sensory evaluation.Results showed that:1?5?6 and 9 group were better than others.In terms of structure,the hardness,adhesiveness,chewiness and resilience were differed significantly except the springness.As to aberration,group A had the highest lightness,while group B had the highest redness and yellowness.In terms of moisture loss,group B and C had the least moisture loss in thaw.Group D had the least fat but highest cellulose and protein content,there for,these samples had the highest nutritional value.The oxidation degree of group B was lowest according to POV and TBA.All in all,group B was the best choice.Namely,oat bran adding amount was 3.09%,the soybean separation protein was 1.62%,compound phosphates quantity was 0.27%relative to the total weight of material.3.Effects of various domestic cooking methods on the sensory characteristics,nutrition,and flavor of oat bran pork meatballsThe effects of domestic cooking methods(boiling,steaming,microwaving and frying)on the basic qualities?volatile flavor compounds and non-volatile flavor compounds of oat bran pork meatballs were investigated.The sensory evaluation and structure analysis showed that fried meatballs were the best;Cooking loss were significantly(P<0.05)affected by different treatment,being higher after microwaving(9.95%)and lower after boiling(2.17%)and steaming(3.41%).The content of moisture decreased after microwaving(50.51%)and frying(59.29%),but increased after boiling(65.72%)and steaming(64.35%).All the cooking methods increased crude protein and crude fat content.The electronic nose and gas chromatography combined with mass spectrometry(GC-MS)showed that all samples varied significantly in fragrance and identified 73 kinds of flavor substances,raw samples had the most total volatile compounds(100.871 AU×106/g wet matter)compared with four cooking samples(between 41.522 and 80.872AU×106/g wet matter),but alcohols,aldehydes and ketones which have a greater effect on flavor increased after cooking,and hydrocarbons,esters and other compounds decreased.The four cooking methods led to increase nucleotide and free amino acid compare to raw samples.GMP and IMP were richest in Microwaving samples(15.684 mg/100 g and 42.450 mg/100 g),followed by fried(13.341 mg/100g and 38.880 mg/100g),boiled(10.551 mg/100g and 36.082 mg/100g),and steamed(10.097 mg/100g and 34.562 mg/100 g)samples.Compared to raw samples(574.404 mg/100 g),amino acid increased most after steaming(2302 mg/100g),and followed by microwaving(1933.760 mg/100 g),boiling(1401.611 mg/100 g)and frying(1334.574 mg/100 g).According to comprehensive indicators,microwaving was the best cooking method to keep the pork meatballs' flavor and taste,though it will damage the appearance slightly.4.The effects of storage conditions on the quality of oat bran pork meatballsFreezing is the most popular storage method used on pork meatballs,good storage conditions can ensure the quality of products.Combined with production practice,this paper explored the changes of sensory evaluation?structure?color?the nucleotide and amino acid content after being stored in-4 ? and-18 ? for 1?2 and 6 months as well as the degree of lipid oxidation for 6 months.Results showed that the sensory evaluation score of the samples stored at-18 ?was lower than those at-4 ?,and as the storage time increased,sensory evaluation score?the brightness and redness gradually reduced while yellowness increased;as the time increased,the content of IMP gradually decreased,but higher than fresh samples at-4 ?,however,IMP had no significant change(P<0.05)at-18 ?;The content of free amino acids also decreased with time increasing,and the lower the temperature,the smaller the content;With time increased,the POV values were reduced,but TBA values were increased,and the samples stored at-18 ? were higher than-4 ?,but as the time increased to 10 weeks,the oxidation process stopped.In a conclusion,the longer the frozen time and the lower the temperature was,the worse the samples were.5.The effects of four different reheating methods on the quality of oat bran pork meatballsReheating is necessary to make frozen pork meatballs edible.In order to know the quality changes of frozen samples after reheating,the paper explored the sensory evaluation,structure,color,the basic composition(moisture content,protein content,fat content),volatile flavor substances(e-nose analysis)and the degree of oxidation of reheating samples(boiled,steamed,microwaved and fried),and made the thawed samples as the control group.The results showed that the steamed and fried samples had the best sensory evaluation,but the apparent states of fried samples were not good.The structure of four groups differed significantly,and the sensory evaluation had very significantly negative correlation with hardness and adhesiveness,and had significant negative correlation with chewiness;Frying made the yellowness and lightness increased,it made the samples have attractive color,meanwhile,it made the protein and fat content increased because of the water loss,and then followed by microwaving;Different reheating methods made the flavor of meatballs differed significantly,and the differentiation of PCA was more obvious than LDA;The oxidation degree of frying samples were the highest,and then followed by boiled,steamed and microwaved samples,the thawed samples were the lowest.