Techniques for postmortem tenderisation in meat processing:effectiveness,application and possible mechanisms

Developing efficient and promising tenderising techniques for postmortem meat is a heavily researched topic among meat scientists as consumers are willing to pay more for guaranteed tender meat.However,emerging tenderising techniques are not broadly used in the meat industry and,to some degree,are controversial due to lack of theoretical support.Thus,understanding the mechanisms involved in postmortem tenderisation is essential.This article first provides an overview of the relationship of ageing tenderisation and calpain system,as well as proteomics applied to identify protein biomarkers characterizing tenderness.In general,the ageing tenderisation is mediated by multiple biochemical activities,and it can exhibit better palatability and commercial benefit by combining other interventions.The calpain system plays a key role in ageing tenderisation functions by rupturing myofibrils and regulating proteolysis,glycolysis,apoptosis and metabolic modification.Additionally,tenderising techniques from different aspects including exogenous enzymes,chemistry,physics and the combined methods are discussed in depth.Particularly,innovation of home cooking could be recommended to prepare relatively tender meat due to its convenience and ease of operation by consumers.Furthermore,the combined interventions provide better performance in controlled tenderness.Finally,future trends in developing new tenderising techniques,and applied consideration in the meat processing industry are proposed in order to improve meat quality with higher economical value.

Antioxidant potential and physicochemical properties of protein hydrolysates from body parts of North Atlantic sea cucumber(Cucumaria frondosa)

Protein hydrolysates were prepared from North Atlantic sea cucumber(Cucumaria frondosa)body wall(BW),and processing by-product flower(FL)and internal organs(IN).Sea cucumber proteins from these three tissues were hydrolysed with selected endopeptidases and exopeptidases.The enzymes used were Alcalase(A),and Corolase(C)as endopeptidases and Flavourzyme(F)with both endo-and exopeptidase functions.These were employed individually or in combination under controlled conditions.The hydrolysates so prepared were subsequently analysed for their antioxidant potential and functionalities in food systems for the first time.Hydrolysates treated with the combination of A and F exhibited the highest radical scavenging activity against DPPH and ABTS radicals.The highest metal chelation activity was observed for samples hydrolysed with the combination of enzymes(C+F and A+F).All treatments inhibited beta-carotene bleaching in an oil-in-water emulsion and TBARS production in a meat model system.In addition,sea cucumber protein hydrolysates were more than 75%soluble over a pH range of 2–12.Hydrolysed proteins were also effective in enhancing water holding capacity in a meat model system compared to their untreated counterparts.The amino acids of sea cucumber protein hydrolysates had desirable profiles with glutamic acid as the predominant component in samples analysed.These findings demonstrate the desirable functionalities of hydrolysates from North Atlantic sea cucumber and their potential for use as functional food ingredients.

A robust stripping method for the removal of minor components from edible oils

Column chromatographic techniques have commonly been used for effective stripping of edible oils from their minor components.However,this method is time consuming,which may lead to oil oxidation.Thus,in the present study,the oils of camelina seed,chia seed,sophia seed,corn,olive,and a docosahexaenoic acid single cell oil(DHASCO)were subjected to a simplified stripping method by using the stationary phase material and examining their minor components such as tocopherols,carotenoids,and chlorophylls as well as their oxidative stability.The results demonstrated that stripped oils prepared by using the simplified stripping method for 2 h were devoid of any tocopherol,chlorophylls and carotenoids and this was as effective as column chromatographic method.Thus,the simplified stripping method provides a facile means of producing stripped oil with better oxidative stability compared to the column chromatographic method.

Compositional characteristics and oxidative stability of chia seed oil(Salvia hispanica L)

Fatty acid composition and triacylglycerols(TAG)profile of chia seed oil were determined.The main fatty acids present in the tested oil wereα-linolenic acid(Ln,61.1%)>linoleic acid(L,16.6%)>palmitic acid(P,6.7%)>oleic acid(O,6.0%)>stearic acid(S,3.2%).Five major triacylglycerols in chia oil were LnLnLn,LnLLn,LnLnP,LnOLn,and LLLn and these contributed more than 76%to the total.The oxidative stability under autoxidative and photooxidative conditions before and after the removal of their minor components was also determined.In addition,tocols,chlorophylls and carotenoids were measured in the oil.Oil samples were stripped of their minor components by using a facile silicic acid and charcoal in one pot rather than in a column.Storage under Schaal oven condition and photooxidation were also monitored for both crude oil(non-stripped)and stripped oil using stationary phase material.Total tocopherol contents were in the order ofβ−/γ-282.68,δ-47.44,andα-tocopherols 10.94 mg/kg of oil.Stripping removed all the minor components including tocopherols,chlorophylls and carotenoids.Oxidative stability of the tested seed oil was primarily affected by its composition of fatty acids,triacylglycerols,minor components,and storage conditions.

Polyphenol composition and antioxidant potential of mint leaves

Soluble and insoluble/bound phenolic compounds and an aqueous infusion of two mint species(Medina and Hasawi),were tested for their total phenolic content,2,2′-azino-bis-3-ethylbenzthiazoline-6-sulphonate(ABTS)and 1,1-diphenyl-2picrylhydrazyl(DPPH)radical scavenging activity,iron(Ⅲ)reduction,iron(Ⅱ)chelating and oxygen radical absorbance capacity(ORAC).Furthermore,the potency of the mint extracts in the inhibition of radical-induced DNA scission,human low-density lipoprotein(LDL)cholesterol oxidation,formation of thiobarbituric acid reactive substances(TBARS)in a cooked ground meat system and LPS(lipopolysaccharide)-stimulated cyclooxygenase-2(COX-2)expression in J774A.1 mouse macrophage cells were monitored.Results showed that the soluble phenolics had a higher phenolic content and antioxidant activity than the insoluble-bound extracts and aqueous infusions in most of the assays.Both varieties exhibited notable antioxidant activities and inhibition of LDL cholesterol oxidation,DNA scission and COX-2 gene expression at transcriptional level.However,Medina mint was a more potent antioxidant than the Hasawi mint.High performance liquid chromatography with online tandem electrospray ionization mass spectrometry(HPLC/ESI-MS/MS)analysis of the extracts revealed that rosmarinic acid was the major phenolic compound present in both mint samples.

Mono-and dioleyl p-coumarate phenolipids and their antioxidant activity in a muscle food model system

Response surface methodology (RSM) was used to optimize the degree of esterification of p-coumaric acid to triolein via lipase-catalyzed acidolysis, and enzyme load, reaction time and mole ratio of substrates were selected as variables in the experimental design. The results showed that the model employed was highly sufficient for determining the effectiveness and interaction of three selected variables, enzyme load, reaction time and the mole ratio of substrates, on the dependent variable, the degree of esterification. Although the optimization point was not found in the selected range of the three variables, the steepest ascent analysis suggested that an increase of these three variables might lead to a stationary point. However, based on the limitations on increasing the range of tested variables, including possible oxidation of synthesized lipids and increased cost, the degree of esterification so yielded in the designed central composite design should be the one closest to the possible ideal optimized degree. The p-coumarates so produced exhibited varying antioxidant performance in the tested muscle food model, which could be explained by their different lipophilicity. Moreover, the potential health benefits of synthesized phenolic lipids have been discussed.

Antiglycative and anti-inflammatory effects of lipophilized tyrosol derivatives

To expand the application of tyrosol,a series of lipophilized tyrosol derivatives were synthesized via esterification of tyrosol with fatty acids of different chain lengths.The antiglycative activity of tyrosol esters so prepared was subsequently examined in the bovine serumalbumin/glucose system.A quasi-parabolic shape was observed when the activity was plotted against alkyl chain length.Additionally,the anti-inflammatory effects of these derivatives were evaluated against methylglyoxalinduced inflammation in RAW264.7 cells.The same trend on anti-inflammatory activity was found as in the antiglycation study.The results showed that tyrosol esters with C12:0 and C14:0 were two most efficient ones among all the tested derivatives.Thus,some lipophilized tyrosol derivatives were stronger antiglycative and anti-inflammatory agents compared to the parent compound,tyrosol.

Effect of processing on the antioxidant activities of porridges and Pittu prepared from finger millets (Eleusine coracana)

Finger millets are important coarse grains that exhibit high levels of phenolic compounds and antioxidant activities among other cereals. Grains are subjected to a number of thermal treatments and this could affect the contents and bioactivities of phenolic compounds. The aim of the present study was to determine the phenolic contents and antioxidant activities of finger millet flour and foods, namely porridges and Pittu subjected to several thermal treatments such as roasting, parboiling, and parboiled roasting of flour and open boiling and steaming of foods prepared using flour. The effect of the addition of spices on phenolic content and antioxidant activities to open boiled foods was determined. Antioxidant activities of phenolic extracts obtained from finger millet flour and foods were studied for their total phenolic, flavonoids and proanthocyanidins contents, radical scavenging capacities, reducing power, ferrous ion chelating capacity, and antioxidant activity in a β-carotene/linoleate emulsion. The roasted flour and foods had higher total phenolic content (TPC) than other counterparts and ranged from 21.58 to 28.63 µmol ferulic acid equivalents/g dry matter. All flour and food preparations exhibited effective inhibition of radicals, reducing power, ferrous ion chelating activity, and antioxidant activity in the β-carotene/linoleate emulsion and the degree of activity depended on the processing conditions adopted in food preparations.Foods prepared using steaming showed lower phenolic content and antioxidant activities in general than those of open-boiled counterparts. The addition of spices, namely garlic and cinnamon improved the phenolic contents and antioxidant activities of open-boiled porridges. The knowledge generated from this study may help to exploit the use of finger millets as a functional food ingredient to promote health and wellness.

Functional properties of protein isolatesfrom camelina (Camelina sativa (L.) Crantz)and flixweed (sophia, Descurainis sophia L.)seed meals

Camelina and flixweed(sophia)seed protein isolates were prepared using both the conventional extraction and ultrasonic-assisted extraction methods at 40 kHz for 20 min,and their functional properties investigated.SDS-PAGE showed that both ultrasound-assisted and conventional extractions resulted in a similar protein profile of the extract.The application of ultrasound significantly improved protein extraction/content and functional properties(water holding capacity,oil absorption capacity,emulsifying foaming properties,and protein solubility)of camelina protein isolate and sophia protein isolate.The water-holding and oil absorption capacities of sophia protein isolate were markedly higher than those of camelina protein isolate.These results suggest that camelina protein isolate and sophia protein isolate may serve as natural functional ingredients in the food industry.

Finger millet porridges subjected to different processing conditions showed low glycemic index and variable efficacy on plasma antioxidant capacity of healthy adults

Finger millet porridges(FMP),rich in nutrient and non-nutrient compounds have been used in the traditional food cultures in Asia.The aims of the study were to determine the effect of different processing conditions of finger millet grains on glycemic response,phenolic content and the antioxidant activities of FMP and to determine the short term and long term efficacy of its consumption on plasma antioxidant levels of healthy adults.Twelve types of FMP were prepared combining different processing conditions.Phenolic content of porridges as well as antioxidant activities were determined.The glycemic index(GI)and glycemic load(GL)values of FMP were also evaluated.The long term efficacy of FMP consumption on plasma glucose(PG),total cholesterol(TC)levels and plasma antioxidant capacity(PAC)of 18 subjects were investigated using a 24 weeks randomized cross-over study.The short term efficacy of porridge consumption on AC was determined.PAC was measured by trolox equivalent antioxidant capacity(TEAC)and ferric ion reducing antioxidant power(FRAP).All FMP exhibited low GI values(<55)except the raw roasted flour which showed high and medium GI values for both particle sizes used.Parboiling of finger millet grains with 15 min steaming produced FMP with low glycemic response and possessed high PAC.Compared to baseline,PAC measured using FRAP and TEAC assays increased after 8 weeks consumption of porridge though significant changes were not observed for PG and TC levels.Furthermore,PAC was increased by 23 and 14%after 2 h of porridge consumption as measured by TEAC and FRAP,respectively.FMP consumption increased the plasma total antioxidant capacity of healthy adults.Further research on examining the potential of FMP on improving the antioxidant capacity in patients with diabetes is warranted.

Natural bioactive substances for the control of food-borne viruses and contaminants in food

Food-borne viruses and contaminants,as an important global food safety problem,are caused by chemical,microbiological,zoonotic,and other risk factors that represent a health hazard.Natural bioactive substances,originating from plants,animals,or microorganisms,might offer the possibility of preventing and controlling foodborne diseases.In this contribution,the common bioactive substances such as polyphenols,essential oils,proteins,and polysaccharides which are effective in the prevention and treatment of food-borne viruses and contaminants are discussed.Meanwhile,the preventive effects of natural bioactive substances and the possible mechanisms involved in food protection are discussed and detailed.The application and potential effects of natural bioactive substances in the adjuvant treatment for food-borne diseases is also described.

Welcome to the Food Production,Processing and Nutrition journal

Food production,processing and nutrition is a multifaceted area of research and development,of interest to many,which has both fundamental and applied components of interest.The field has undergone rapid advances in each of its components which starts with the food production,whether land-based farms or aquatic areas related to fisheries and aquaculture,to gene manipulation,variety improvement and selection as well as further studies that include proteomic,lipidomic and foodomic,among others.Furthermore,green processing,food safety,elimination of contaminants and retention of bioactive components using both thermal and non-thermal processing,are rapidly expanding our horizons.Of course,full attention must also be paid to ultra-processed foods that may provide variety but this could come at the price of including components that may lead to obesity and other health concerns if not properly designed.Of course,processing methods and their effect on nutritional components must be carefully considered as they play a major role in health promotion and disease risk reduction.Therefore important aspects related to production technologies,absorption,bioavailability,metabolism and personalized nutrition with consideration of gut microbiota need to be carefully examined.