BIOFOAMS ARE A CHALLENGE FOR SCIENTISTS IN TERMS OF INNOVATION. INCORPORATION OF CELLULOSE FIBRILS (CF), MIGHT HELP IMPROVE THE MICROSTRUCTURE OF FOAMS, THUS THIS STUDY FOCUSES ON STUDYING THE IMPACT OF CF ON THE FOAMING PROPERTIES AND RHEOLOGY OF LENTIL PROTEIN (LP) FOAMS AT VARIOUS PH AND CF CONCENTRATIONS. ADDITIONALLY, LP-CF MIXTURES WERE TRANSFORMED INTO SOLID FOAMS, AND THEIR MICROSTRUCTURE, PHYSICAL PROPERTIES, AND MORPHOLOGY WERE EVALUATED. CF CONCENTRATION SIGNIFICANTLY IMPACTED ON LP-CF FOAM PROPERTIES, PRIMARILY DUE TO HIGH VISCOSITY VALUES. INCREASED CF CONCENTRATION RESULTED IN IMPROVED FS VALUES (UP TO 77 MIN) AT ALL PH VALUES. THIS IS LIKELY ATTRIBUTED TO ASSOCIATIVE INTERACTIONS AND COACERVATES FORMATION. ALSO, FOAM MICROSTRUCTURE COULD BE RELATED TO APPARENT VISCOSITY, SUGGESTING THE ROLE OF VISCOSITY IN PRESERVING THE INTEGRITY OF THE WET FOAM STRUCTURE DURING FREEZING AND LYOPHILIZATION PROCESSES. HOWEVER, ELEVATED VISCOSITY VALUES MIGHT NEGATIVELY IMPACT PROPERTIES SUCH AS FOAMING CAPACITY AND PRODUCE DENSER MICROSTRUCTURES. THE MICROSTRUCTURE AND MORPHOLOGY ANALYSIS REVEALED THAT CERTAIN FOAMS EXHIBITED A SPONGE-LIKE STRUCTURE WITH OPEN PORES AND SEMI-SPHERICAL SHAPES, SUPPORTED BY CF FIBERS EXTENDING AND FORMING LAYERS. HOWEVER, THE STRUCTURE ITSELF WAS IRREGULAR. WHILE OTHERS EXHIBITED NON-UNIFORM, IRREGULAR PORE SIZE, AND SHAPE, ALONG WITH A DENSER STRUCTURE. THESE FINDINGS CONTRIBUTE TO UNDERSTANDING THE BEHAVIOR OF LP-CF MIXTURES, ALTHOUGH ADDITIONAL INVESTIGATIONS ON MECHANICAL PROPERTIES, BIODEGRADABILITY, AND HYDROPHOBICITY ARE NECESSARY TO REACH THEIR FULL POTENTIAL FOR VARIOUS APPLICATIONS.

BACKGROUND DRYING IS ONE OF THE OLDEST PRESERVATION TECHNIQUES USED IN THE FOOD INDUSTRY. THIS TECHNOLOGY HAS EVOLVED AND DIFFERENT DRYING SYSTEMS HAVE BEEN APPLIED, SUCH AS CONVECTION, CONDUCTION, OR RADIATION, AND COMBINATIONS THEREOF. SCOPE AND APPROACH THIS REVIEW STUDIES THE VMD PROCESS WHOSE PRINCIPLE IS BASED ON THE ELECTROMAGNETIC RADIATION EMITTED BY THE MAGNETRON ON A FOOD MATRIX IN A REDUCED PRESSURE ENVIRONMENT AND WHICH IS TRANSFORMED INTO HEAT. VMD IS A PROMISING, FAST, AND EFFICIENT PROCESS FOR REDUCING MOISTURE CONTENT. BOTH RESEARCH AND INDUSTRIAL USE HAVE GROWN BY 303% IN THE LAST 20 YR. THE OBJECTIVE OF THIS REVIEW IS TO PROVIDE AN OVERVIEW OF MAJOR DEVELOPMENTS IN VMD RESEARCH AND ITS APPLICATION IN VARIOUS FOODS AND OTHER MATERIALS. BASED ON THE CHARACTERISTICS AND PARAMETERS OF THE VMD EQUIPMENT IN THE DRYING PROCESS, IT WAS POSSIBLE TO CLASSIFY THE EFFECT VMD HAS ON DIFFERENT FOOD MATRICES. KEY FINDINGS AND CONCLUSIONS THE REVIEW DESCRIBES THE PHENOMENOLOGICAL BEHAVIOR OF THE DRYING PROCESS AND HOW TO OPTIMIZE IT USING EQUIPMENT MODIFICATIONS WITH COMPUTER SIMULATIONS. THE DIFFERENT VMD SYSTEMS HAVE BEEN CLASSIFIED AS STATIC, ROTARY, CONTINUOUS FLOW, AND PROPRIETARY EQUIPMENT. IN ADDITION TO SOME CHARACTERISTICS OF PROCESS EFFICIENCY AND ENERGY CONSUMPTION, VMD EXHIBITS ENERGY CONSUMPTION SAVINGS OF APPROXIMATELY 50% COMPARED WITH OTHER DRYING SYSTEMS. FINALLY, PRODUCT QUALITY IS DISCUSSED UNDER DIFFERENT CONDITIONS, SUCH AS EQUIPMENT DESIGN AND TEMPERATURE UNIFORMITY. THUS, IT IS CHALLENGING TO DESIGN AND BUILT NEW VMD SYSTEMS WITH HIGHER ENERGY EFFICIENCY IN FOOD DRYING.

LIPOSOMES PROVIDE PROTECTION, TRANSPORT, AND DELIVERY SYSTEMS FOR DRUGS AND FUNCTIONAL INGREDIENTS. THIS REVIEW STUDIED LIPOSOME-BASED FUNCTIONAL INGREDIENTS, EFFECTS OF ELECTRIC FIELDS ON LIPID MEMBRANES, METHODS TO DETERMINE THE DEGREE OF ELECTROPORATION, AND SOME GOVERNING EQUATIONS OF THE ELECTROPORATION PHENOMENON. THE OBJECTIVE OF THIS REVIEW WAS TO PROVIDE AN OVERVIEW OF SOME ASPECTS TO CONSIDER WHEN DESIGNING AND MANUFACTURING FOOD LIPOSOMES THAT ARE STABLE IN ELECTRIC FIELDS; THIS WAS BASED ON STUDIES CONDUCTED IN MEDICINE, PHARMACOLOGY, AND THE FOOD INDUSTRY. THE EFFECTS OF PULSED ELECTRIC FIELDS AND HIGH VOLTAGE ELECTRICAL DISCHARGE PROCESSING ON PHOSPHOLIPID MEMBRANES WERE STUDIED; THESE CAN BE EXTRAPOLATED TO LIPOSOMES UNDER FOOD PROCESSING CONDITIONS USING ELECTRIC FIELDS. THE CHEMICAL COMPOSITIONS OF THE LIPID MEMBRANE AND ADDING LAYERS TO THE LIPOSOME SURFACE WERE RELATED TO HIGHER ELECTRICAL RESISTANCE. FLUORESCENCE, IMPEDANCE, CONDUCTIVITY, AND VOLTAGE METHODS WERE DEFINED TO DETERMINE THE DEGREE OF ELECTROPORATION AND MATHEMATICAL MODELS THAT CAN FACILITATE THE ANALYSIS OF THE MECHANISM. FINALLY, THE STUDY OF THE ELECTRICAL PROPERTIES USED BY THE DIFFERENT MATERIALS TO MANUFACTURE LIPOSOMES REMAINS FOR FUTURE RESEARCH.

THE AIM OF THIS STUDY WAS TO EVALUATE THE INFLUENCE OF HIGH HYDROSTATIC PRESSURE (150, 250, 350, 450, AND 550 MPA), APPLIED FOR 5 MINUTES, ON ANTIOXIDANT CAPACITY, TOTAL PHENOLIC CONTENT, COLOR, FIRMNESS, REHYDRATION RATIO, AND WATER HOLDING CAPACITY OF ALOE VERA GEL STORED FOR 60 DAYS AT 4 °C. THE ANALYZED PROPERTIES OF THE PRESSURIZED GEL SHOWED SIGNIFICANT CHANGES AFTER THE STORAGE PERIOD. THE HIGHEST VALUE OF TOTAL PHENOLIC CONTENT WAS FOUND AT 550 MPA. HOWEVER, A DECREASE IN THE ANTIOXIDANT CAPACITY WAS OBSERVED FOR ALL PRESSURIZED GEL SAMPLES WHEN COMPARED TO THE CONTROL SAMPLE (P < 0.05). THE SMALLEST CHANGES IN PRODUCT COLOR WERE OBSERVED AT PRESSURE LEVELS BETWEEN 150 AND 250 MP. THE APPLICATION OF HIGH HYDROSTATIC PRESSURE RESULTED IN LOWER GEL FIRMNESS, AND THE LOWEST VALUE WAS FOUND AT 150 MPA (P < 0.05). ON THE OTHER HAND, THE UNTREATED SAMPLE SHOWED A GREATER DECREASE IN FIRMNESS, INDICATING THAT HIGH PRESSURE PROCESSING PRESERVES THIS PROPERTY. THE APPLICATION OF HIGH HYDROSTATIC PRESSURE EXHIBITED MODIFICATIONS IN THE FOOD MATRIX, WHICH WERE EVALUATED IN TERMS OF REHYDRATION RATIO AND WATER HOLDING CAPACITY.

THE AIM OF THIS STUDY WAS TO EVALUATE THE INFLUENCE OF HIGH HYDROSTATIC PRESSURE (150, 250, 350, 450, AND 550 MPA), APPLIED FOR 5 MINUTES, ON ANTIOXIDANT CAPACITY, TOTAL PHENOLIC CONTENT, COLOR, FIRMNESS, REHYDRATION RATIO, AND WATER HOLDING CAPACITY OF ALOE VERA GEL STORED FOR 60 DAYS AT 4 °C. THE ANALYZED PROPERTIES OF THE PRESSURIZED GEL SHOWED SIGNIFICANT CHANGES AFTER THE STORAGE PERIOD. THE HIGHEST VALUE OF TOTAL PHENOLIC CONTENT WAS FOUND AT 550 MPA. HOWEVER, A DECREASE IN THE ANTIOXIDANT CAPACITY WAS OBSERVED FOR ALL PRESSURIZED GEL SAMPLES WHEN COMPARED TO THE CONTROL SAMPLE (P < 0.05). THE SMALLEST CHANGES IN PRODUCT COLOR WERE OBSERVED AT PRESSURE LEVELS BETWEEN 150 AND 250 MP. THE APPLICATION OF HIGH HYDROSTATIC PRESSURE RESULTED IN LOWER GEL FIRMNESS, AND THE LOWEST VALUE WAS FOUND AT 150 MPA (P < 0.05). ON THE OTHER HAND, THE UNTREATED SAMPLE SHOWED A GREATER DECREASE IN FIRMNESS, INDICATING THAT HIGH PRESSURE PROCESSING PRESERVES THIS PROPERTY. THE APPLICATION OF HIGH HYDROSTATIC PRESSURE EXHIBITED MODIFICATIONS IN THE FOOD MATRIX, WHICH WERE EVALUATED IN TERMS OF REHYDRATION RATIO AND WATER HOLDING CAPACITY.

EFFECTS OF PULSED ELECTRIC FIELDS (PEF: 1?2 KV/CM, 20 ?S) USED ALONE AND COMBINED WITH CARBON DIOXIDE (CO2: 70%) AND HIGH HYDROSTATIC PRESSURE (HP: 150 MPA, 5 MIN) ON THE PHYSICOCHEMICAL PROPERTIES AND MICROBIOLOGICAL SHELF LIFE OF COHO SALMON UNDER PRE- AND POST-RIGOR CONDITIONS WERE STUDIED DURING REFRIGERATED STORAGE (25 DAYS). THE PEF + CO2 + HP TREATMENTS REDUCED COLOR CHANGES IN PRE-RIGOR MORE THAN IN POST-RIGOR SALMON. TEXTURE CHANGES OF PRE- AND POST-RIGOR SALMON DIFFERED BETWEEN UNTREATED AND TREATED SALMON. COMBINED TREATMENTS ALSO EFFECTIVELY REDUCED THE PROTEASE AND LIPASE ACTIVITY OF PRE-RIGOR SALMON. COLLAGENASE ACTIVITY OF POST-RIGOR SALMON REMAINED LOW IN ALL TREATMENTS. PRINCIPAL COMPONENT ANALYSIS SHOWED A CLEAR DIFFERENCE BETWEEN PRE- AND POST-RIGOR STATES IN THE EVALUATED PARAMETERS; HOWEVER, MICROBIOLOGICAL SHELF LIFE INCREASED WITH PEF + CO2 REGARDLESS OF THE RIGOR CONDITION. IN CONCLUSION, COMBINED PEF, CO2, AND HP TREATMENTS CAN IMPROVE SALMON QUALITY DURING REFRIGERATED STORAGE AND THUS EXTEND ITS MICROBIAL SHELF LIFE.

THIS STUDY FOCUSED ON APPLYING DIFFERENT HIGH HYDROSTATIC PRESSURE + CARBON DIOXIDE (HHP + CO2) PROCESSING CONDITIONS ON REFRIGERATED (4 °C, 25 DAYS) FARMED COHO SALMON (ONCORHYNCHUS KISUTCH) TO INACTIVATE ENDOGENOUS ENZYMES (PROTEASE, LIPASE, COLLAGENASE), PHYSICOCHEMICAL PROPERTIES (TEXTURE, COLOR, LIPID OXIDATION), AND MICROBIAL SHELF LIFE. SALMON FILLETS WERE SUBJECTED TO COMBINED HHP (150 MPA/5 MIN) AND CO2 (50%, 70%, 100%). PROTEASE AND LIPASE INACTIVATION WAS ACHIEVED WITH COMBINED HHP + CO2 TREATMENTS IN WHICH LIPASE ACTIVITY REMAINED LOW AS OPPOSED TO PROTEASE ACTIVITY DURING STORAGE. COLLAGENASE ACTIVITY DECREASED APPROXIMATELY 90% DURING STORAGE WHEN APPLYING HHP + CO2. COMBINED TREATMENTS LIMITED THE INCREASE IN SPOILAGE INDICATORS, SUCH AS TOTAL VOLATILE AMINES AND TRIMETHYLAMINE. THE 150 MPA + 100% CO2 TREATMENT WAS THE MOST EFFECTIVE AT MAINTAINING HARDNESS AFTER 10 DAYS OF STORAGE. COMBINED TREATMENTS LIMITED HHP-INDUCED COLOR CHANGE AND REDUCED THE EXTENT OF CHANGES CAUSED BY STORAGE COMPARED WITH THE UNTREATED SAMPLE. MICROBIAL SHELF LIFE WAS EXTENDED BY THE CO2 CONTENT AND NOT BY THE HHP TREATMENTS; THIS RESULT WAS RELATED TO AN INCREASED LAG PHASE AND DECREASED GROWTH RATE. IT CAN BE CONCLUDED THAT COMBINING HHP AND CO2 COULD BE AN EFFECTIVE METHOD OF INACTIVATING ENDOGENOUS ENZYMES AND EXTEND SALMON SHELF LIFE.

THE FOCUS OF THIS RESEARCH WAS BASED ON THE APPLICATION OF AN OSMOTIC PRETREATMENT (15% NACL) FOR DRYING ABALONE SLICES, AND IT EVALUATES THE INFLUENCE OF HOT-AIR DRYING TEMPERATURE (40?80°C) ON THE PRODUCT QUALITY. IN ADDITION, THE MASS TRANSFER KINETICS OF SALT AND WATER WAS ALSO STUDIED. THE OPTIMAL TIME OF THE OSMOTIC TREATMENT WAS ESTABLISHED UNTIL REACHING A PSEUDO EQUILIBRIUM STATE OF THE WATER AND SALT CONTENT (290?MIN). THE WATER EFFECTIVE DIFFUSIVITY VALUES DURING DRYING RANGED FROM 3.76 TO 4.75 × 10?9?M2/S FOR THREE SELECTED TEMPERATURES (40, 60, AND 80°C). IN ADDITION, EXPERIMENTAL DATA WERE FITTED BY WEIBULL DISTRIBUTION MODEL. THE MODIFIED WEIBULL MODEL PROVIDED GOOD FITTING OF EXPERIMENTAL DATA ACCORDING TO APPLIED STATISTICAL TESTS. REGARDING THE EVALUATED QUALITY PARAMETERS, THE COLOR OF THE SURFACE SHOWED A CHANGE MORE SIGNIFICANT AT HIGH TEMPERATURE (80°C), WHEREAS THE NONENZYMATIC BROWNING AND TEXTURE SHOWED A DECREASE DURING DRYING PROCESS MAINLY DUE TO CHANGES IN PROTEIN MATRIX AND REHYDRATION RATES, RESPECTIVELY. IN PARTICULAR, WORKING AT 60°C RESULTED IN DRIED SAMPLES WITH THE HIGHEST QUALITY PARAMETERS.

THE AIM OF THIS STUDY WAS TO DEVELOP A MATHEMATICAL PROTOCOL (MP) TO GRAPHICALLY ANALYZE THE IRREVERSIBLE CHANGES INDUCED BY HIGH PRESSURE TREATMENT IN FISH MUSCLE PROTEIN. THE MP WAS VALIDATED BY THERMAL ANALYSIS DATA (DSC) FROM PRESSURIZED SAMPLES OF SERIOLELLA VIOLACEA MUSCLE TISSUE BETWEEN 200 AND 500 MPA FOR 2 S TO 10 MIN. THE MP INCLUDED METHODOLOGIES TO OBTAIN THE THERMODYNAMIC PARAMETERS OF PROTEIN DENATURATION AND BUILDING 3-D PLOTS FROM REPRESENTATIVE THERMOGRAMS. RESULTS OBTAINED FROM THE APPLICATION OF THE MP SHOWED THAT THE PRESSURIZATION OF MUSCLE TISSUE PROVOKED THAT THE TOTAL DENATURATION ENTHALPIES VALUES DIMINISHED, THESE CHANGES WERE MORE EVIDENT FOR TREATMENTS >450 MPA. THE IRREVERSIBLE DENATURATION OF ACTIN IN THE PRESSURIZED SAMPLES WAS OBSERVED FOR ANY TREATMENT CONDITION >300 MPA AND GREATER THAN 3 MIN. THE PROPOSED MP IS A POWERFUL TOOL TO IMPROVE DATA ANALYSIS FROM DSC WHEN MUSCLE TISSUE SAMPLES ARE SUBJECTED TO PRESSURIZATION.

EMULGELS COULD BE USED AS EDIBLE INKS FOR INDIVIDUALS WITH SPECIAL NEEDS. THE PURPOSE OF THIS WORK WAS TO FORMULATE A 3D PRINTABLE LOW-OIL EMULGEL BY EVALUATING THE EFFECT OF INCORPORATING GELATIN IN A BEAN-BASED NANOEMULSION STABILIZED BY HIGH-PRESSURE HOMOGENIZATION (HPH) SUITABLE FOR A DYSPHAGIA DIET. THE EFFECT OF PHYSICOCHEMICAL PROPERTIES AND PRINTING PARAMETERS OF THE EMULSION NETWORK WERE EVALUATED FOR PRINTABILITY, DIMENSIONAL STABILITY, AND TEXTURAL PROPERTIES. HPH PRODUCED STABLE NANOEMULSIONS USING PRESSURES >200 MPA AND 5% BEAN PROTEIN. ADDING GELATIN DECREASED NH AND COO VIBRATIONS, INCREASED HYDROGEN BONDING, AND CREATED SELF-SUPPORTING EMULGELS WHEN THE GELATIN CONCENTRATION WAS >1.5%. PRINTING PERFORMANCE, DIMENSIONAL STABILITY, AND TEXTURAL PROPERTIES DEPENDED ON THE GELATIN CONCENTRATION AND PRINTING PARAMETERS, WHOSE IMPROVEMENT ENABLED PRECISE, TIME-STABLE, AND SWALLOW-SAFE SHAPES WITH 2.5% GELATIN. IN CONCLUSION, STABLE EMULGELS CAN BE USED IN 3D PRINTING, FACILITATING THE DESIGN OF COLLOIDAL FOOD SYSTEMS WITH CUSTOMIZED TEXTURES AND NUTRITIONAL PROPERTIES FOR INDIVIDUALS WITH DYSPHAGIA.

LIPID DAMAGE EVOLUTION WAS ANALYZED IN CHILLED CHILEAN JACK MACKEREL (TRACHURUS MURPHYI) PREVIOUSLY TREATED WITH HIGH HYDROSTATIC PRESSURE (HHP) TECHNOLOGY. DIFFERENT PRESSURE LEVELS AND PRESSURE HOLDING TIMES WERE TESTED. IN ADDITION, FISH CORRESPONDING TO PRE- AND POST-RIGOR MORTIS (RM) STAGES WERE COMPARATIVELY STUDIED. PREVIOUS HHP TREATMENT LED TO A MARKED LIPID HYDROLYSIS INHIBITION IN CHILLED FISH. INCREASING THE PRESSURE LEVEL AND PRESSURE HOLDING TIME LED TO A LOWER FREE FATTY ACID CONTENT, WITH THE EFFECT OF PRESSURE BEING MORE RELEVANT. ACCORDING TO THE ANALYSIS OF DIFFERENT TYPES OF LIPID OXIDATION INDEXES, NO EFFECT OF THE PREVIOUS HHP TREATMENT ON THE LIPID OXIDATION DEVELOPMENT COULD BE DETERMINED IN CHILLED JACK MACKEREL. CONCERNING THE EFFECT OF THE RM STAGE OF RAW FISH, A HIGHER PRIMARY AND SECONDARY LIPID OXIDATION DEVELOPMENT WAS OBSERVED IN FISH CORRESPONDING TO THE POST-RM CONDITION THROUGHOUT THE CHILLED STORAGE; ALTHOUGH A DEFINITE EFFECT ON LIPID HYDROLYSIS COULD NOT BE FOUND.

ABALONE (HALIOTIS SPP.) IS AN EXOTIC SEAFOOD PRODUCT RECOGNIZED AS A PROTEIN SOURCE OF HIGH BIOLOGICAL VALUE. TRADITIONAL METHODS USED TO PRESERVE FOODS SUCH AS DRYING TECHNOLOGY CAN AFFECT THEIR NUTRITIONAL QUALITY (PROTEIN QUALITY AND DIGESTIBILITY). A 28-DAY RAT FEEDING STUDY WAS CONDUCTED TO EVALUATE THE EFFECTS OF THE DRYING PROCESS ASSISTED BY HIGH-PRESSURE IMPREGNATION (HPI) (350, 450, AND 500 MPA × 5 MIN) ON CHEMICAL PROXIMATE AND AMINO ACID COMPOSITIONS AND NUTRITIONAL PARAMETERS, SUCH AS PROTEIN EFFICIENCY RATIO (PER), TRUE DIGESTIBILITY (TD), NET PROTEIN RATIO, AND PROTEIN DIGESTIBILITY CORRECTED AMINO ACID SCORE (PDCAAS) OF DRIED ABALONE. THE HPI-ASSISTED DRYING PROCESS ENSURED EXCELLENT PROTEIN QUALITY BASED ON PER VALUES, REGARDLESS OF THE PRESSURE LEVEL. AT 350 AND 500 MPA, THE HPI-ASSISTED DRYING PROCESS HAD NO NEGATIVE EFFECT ON TD AND PDCAAS THEN, BASED ON NUTRITIONAL PARAMETERS ANALYSED, WE RECOMMEND HPI-ASSISTED DRYING PROCESS AT 350 MPA × 5 MIN AS THE BEST PROCESS CONDITION TO DRY ABALONE. VARIATIONS IN NUTRITIONAL PARAMETERS COMPARED TO CASEIN PROTEIN WERE OBSERVED; NEVERTHELESS, THE HIGH PROTEIN QUALITY AND DIGESTIBILITY OF HPI-ASSISTED DRIED ABALONES WERE MAINTAINED TO SATISFY THE METABOLIC DEMANDS OF HUMAN BEINGS.

THE EFFECT OF HIGH HYDROSTATIC PRESSURE (HHP) TREATMENTS (450 AND 550 MPA FOR 3 AND 4 MIN AT 20 °C) ON THE MICROBIAL BEHAVIOUR AND SHELF-LIFE EXTENSION OF CHILEAN JACK MACKEREL (TRACHURUS MURPHYI) DURING CHILLED STORAGE AT 4 °C WAS STUDIED. AEROBIC MESOPHILIC AND PSYCHROPHILIC MICROORGANISMS, AS WELL AS HYDROGEN SULPHIDE-PRODUCING BACTERIA (MAINLY SHEWANELLA PUTREFACIENS) WERE ENUMERATED IMMEDIATELY AFTER TREATMENT AND DURING SUBSEQUENT STORAGE AT 4 °C. PHYSICOCHEMICAL PARAMETERS SUCH AS PH AND TMA-N WERE ALSO RECORDED. RESULTS SHOWED THAT HHP TREATMENTS WERE EFFECTIVE IN REDUCING INITIAL MICROBIAL COUNTS AND DELAYED MICROBIAL GROWTH DURING REFRIGERATED STORAGE. HHP TREATMENTS WERE ALSO EFFECTIVE IN DELAYING TMA-N PRODUCTION IN THE FISH DURING STORAGE. AS A RESULT, MICROBIOLOGICAL SHELF-LIFE WAS SIGNIFICANTLY (P < 0.05) EXTENDED FROM ~ 6 DAYS (CONTROL SAMPLES) TO ~ 29 AND ~ 40 DAYS IN PRESSURISED SAMPLES AT 450 MPA/3 MIN AND 550 MPA/4 MIN, RESPECTIVELY.

THE AIM OF THIS STUDY WAS TO EVALUATE THE EFFECTS OF HIGH HYDROSTATIC PRESSURE TREATMENT AT THREE PRESSURE LEVELS (300, 400 AND 500MPA) ON THE FUNCTIONAL AND QUALITY CHARACTERISTICS OF ALOE VERA GEL INCLUDING VITAMIN C AND E, ALOIN, MINERALS, PHENOLIC CONTENT AND ANTIOXIDANT ACTIVITY. THE RESULTS SHOW THAT HHP EXERTED A CLEAR INFLUENCE ON MINERALS CONTENT, VITAMIN C AND E CONTENT, ANTIOXIDANT ACTIVITY, TOTAL PHENOLIC AND ALOIN CONTENT. AFTER 35DAYS OF STORAGE ALL TREATED SAMPLES PRESENTED A DECREASE IN MINERAL CONTENT, EXCEPT FOR PHOSPHORUS. TOTAL PHENOLIC CONTENT AND VITAMIN C AND E CONTENT DECREASED AT HIGH PRESSURES (500MPA), WHILE ALL PRESSURISED SAMPLES SHOWED A HIGHER ANTIOXIDANT ACTIVITY AND ALOIN CONTENT THAN UNTREATED SAMPLE AFTER 35DAYS OF STORAGE. THE MAXIMUM VALUES OF ANTIOXIDANT ACTIVITY AND ALOIN WERE 6.55±1.26?G/ML AT 300MPA AND 24.23±2.27MG/100G D.M. AT 400MPA.

THE EFFECT OF HIGH HYDROSTATIC PRESSURE (HHP) AND OTHER PRETREATMENTS ON THE DRYING KINETICS, ANTIOXIDANT ACTIVITY, FIRMNESS AND MICROSTRUCTURE OF ALOE VERA GEL WAS INVESTIGATED DURING CONVECTIVE DRYING AT 70 °C. THE PRETREATMENTS ANALYZED WERE HIGH HYDROSTATIC PRESSURE, BLANCHING, ENZYMATIC AND MICROWAVES. SIMULATION OF DRYING CURVES WAS STUDIED THROUGH THE APPLICATION OF SEVERAL MATHEMATICAL MODELS SUCH AS NEWTON, HENDERSON AND PABIS, PAGE, MODIFIED PAGE, WANG AND SINGH, AND WEIBULL. AMONG THEM, THE WEIBULL MODEL PROVIDED THE BEST FIT FOR THE EXPERIMENTAL DATA. ALL PRETREATMENTS INCREASED THE WATER DIFFUSION COEFFICIENT COMPARED TO THE CONTROL SAMPLE. MICROWAVES FOLLOWED BY HHP PRESENTED THE FASTEST DRYING RATES. ALL PRETREATMENTS MODIFIED THE MICROSTRUCTURE AND HENCE THE TEXTURE OF THE PRODUCT. HHP AND MICROWAVES INCREASED FIRMNESS WHILE BLANCHING AND ENZYMATIC TREATMENTS PRODUCED A SOFTER FINAL PRODUCT. BLANCHING, MICROWAVES AND HHP ENHANCED A. VERA ANTIOXIDANT ACTIVITY. HOWEVER, THE HHP PRETREATED SAMPLES SHOWED THE HIGHEST ANTIOXIDANT ACTIVITY COMPARED TO THE REST. BASED ON THESE RESULTS, HHP TOGETHER WITH CONVECTIVE DRYING OFFERS THE CHANCE OF PRODUCING DRIED ALOE WITH HIGH ANTIOXIDANT ATTRIBUTES.

TO IDENTIFY PROCESSING CONDITIONS THAT BETTER MAINTAIN PALM RUFF QUALITY ATTRIBUTES, HIGH HYDROSTATIC PRESSURE (HHP) WAS APPLIED TO PRE- AND POST-RIGOR FILLETS. PHYSICAL PARAMETERS AS WHITENESS INDEX (WI), WATER HOLDING CAPACITY (WHC), TEXTURE AND ULTRASTRUCTURE AND SHELF LIFE WERE EVALUATED AFTER THE APPLICATION OF 450 AND 550 MPA (3 AND 4 MIN) AND DURING COLD STORAGE. PRE-RIGOR FILLETS RETAINED LESS WATER AND WERE SOFTER THAN POST RIGOR, ALTHOUGH THE ONSET OF RIGOR INCREASED PALM RUFFS WHC AND FIRMNESS. APPLICATION OF HHP WHITENED PALM RUFFS DARK FLESH; HOWEVER, THIS EFFECT REVERTED AT THE END OF THE STORAGE. PRESSURIZED POST-RIGOR SAMPLES RETAINED LESS WATER THAN THE CONTROL AND STORAGE CAUSED A WHC INCREASE IN SAMPLES PRESSURIZED AT 550 MPA, INDEPENDENT ON THE RIGOR CONDITION. POST-RIGOR FILLETS SOFTENED AT PRESSURES OF 450-550 MPA APPEARING TO HAVE A LOWER THRESHOLD THAN BEEF OR COD (ABOVE 600 MPA). ULTRASTRUCTURAL CHANGES REVEALED A SUBTLE CONTRACTION (7.4%) OF THE MYOFIBRILS IN THE UNPRESSURIZED POST-RIGOR MUSCLE COMPARED TO PRE-RIGOR; AFTER 26 DAYS' STORAGE BOTH SAMPLES PRESENTED EXTENSIVE MUSCLE DEGRADATION AND SARCOMERE LENGTH WAS REDUCED IN 30%. HHP INDUCED PRESSURE DEPENDENT SHORTENING OF THE SARCOMERE AND MODIFICATIONS TO THE STRUCTURE WHICH AFTER 550 MPA WAS HARDLY RECOGNIZABLE. AFTER 26 DAYS' STORAGE, THERE WAS ONLY SLIGHT DEGRADATION OF THE ULTRASTRUCTURE, SHOWING THAT BEYOND THE STRUCTURAL MODIFICATIONS CAUSED BY HHP, POST-MORTEM DETERIORATION IS DELAYED IN HHP-TREATED FILLETS. FURTHERMORE, HHP EXTENDED PALM RUFFS SHELF LIFE TO 14-23 DAYS. THUS, HHP MAY BE CONSIDERED AS A TECHNOLOGY THAT MAINTAINS THE TEXTURAL QUALITY AND SHELF LIFE OF FRESH AND STORED FISH.