Table 5.
Effect of processing on fish protein solubility, antigenicity, and allergenicity.
| Fish Matrix | Processing Method | Method | Antibody | Major Results | Explanation | Reference |
|---|---|---|---|---|---|---|
| Pacific mackerel protein extracts | 60, 80, 100, 120, 140 °C for 5, 10, 15, 20, 25, 30 min | Western blot | mAb PARV-19 | Parvalbumin band decreased as a function of heating temperature and time | The reduction was caused by heat-induced conformational change due to the release of calcium | [30] |
| Indirect non-competitive ELISA | Human IgE | IgE reactivity decreased as a function of heating temperature and time; a complete loss of IgE reactivity at 140 °C | ||||
| Hilsa, pomfret, bhetki, and mackerel | 90 °C for 10 min | Indirect non-competitive ELISA | Human IgE | A decrease in IgE reactivity was observed in pomfret, hilsa, and mackerel while an increase in IgE reactivity was seen in bhetki | Boiling removed many polypeptide bands | [110] |
| Skin prick test | Patients exhibited different reactions to boiled fish | |||||
| Fry with mustard oil for 5 min | Indirect non-competitive ELISA | Human IgE | A decrease in IgE reactivity was observed in pomfret, hilsa, and mackerel while an increase in IgE reactivity was seen in bhetki | Frying removed many polypeptide bands and caused protein denaturation to form high molecular weight proteins | ||
| Skin prick test | Patients exhibited different reactions to boiled fish | |||||
| Snapper, silver bream, yellowtail kingfish, barramundi, bluefin tuna, slimy mackerel, orange roughy, tiger flathead, Atlantic salmon, rainbow trout, carp, pilchard, rock ling, Atlantic cod, | 95 °C for 15 min | Western blot | mAb PARV-19 | Parvalbumin from heated fish was still immunodetectable. Especially for yellowfin tuna, a stronger and more intense parvalbumin band was observed compared to unheated extracts | Heat processing affected antibody–antigen interaction differently for each species | [111] |
| gummy shark, sparsely spotted stingaree, blacktip shark, and elephant shark | 95 °C for 15 min | Western blot | mAb PARV-19 | Except for elephant shark, immunoreactive parvalbumin was not visible | ||
| Purified cod parvalbumin | 80 °C for 30 min | Indirect non-competitive ELISA | Human IgE | IgE binding was not affected | Heat-induced secondary structure and calcium-binding ability changes were not enough to reduce antigenicity | [112] |
| 80 °C, 300 MPa for 30 min | IgE binding was not affected | |||||
| Bhetki and mackerel fish extracts | 90 °C, 10 min then pepsin digested | Indirect non-competitive ELISA | No significant difference in IgE level was observed | [113] | ||
| Western blot | Additional immunoreactive protein bands were observed | Thermal processing generated new allergenic epitopes that were pepsin stable | ||||
| Fry in mustard oil for 5 min then pepsin digested | Western blot | Increased IgE binding proteins were observed | Structural changes may offer some protection from enzymatic digestion | |||
| Surimi | 100 °C for 10, 15, and 20 min | Indirect non-competitive ELISA and indirect competitive ELISA |
Anti-fish tropomyosin mAb | IgG binding decreased after 10 min and remained constant for 15 and 20 min | High temperature and long processing time decreased extractable protein concentration, destroyed epitopes, and affected antibody–antigen interaction | [114] |
| Steam at 100 °C for 10, 15, and 20 min | IgG binding decreased after 10 min and remained constant for 15 and 20 min | |||||
| Bake at 149 °C for 10, 20, and 30 min | IgG binding decreased as a function of baking temperature | |||||
| Microwave on high power for 0.5, 1, and 1.5 min | IgG binding decreased as a function of microwaving temperature | |||||
| Fry in canola oil for 0.5, 1, and 1.5 min | IgG binding decreased after 10 min and remained constant for 15 and 20 min | |||||
| Purified cod parvalbumin | Glycation with D-glucose (60 °C for 5 h) and in vitro digestion | SDS-PAGE | All parvalbumin was digested after 30 min | Reduced aggregation during processing allowed a better protein degradation by pepsin | [115] | |
| Fish protein hydrolysates | Glycation with ribose at 121 °C for 30, 60, and 90 min | Histamine release using RBL-2H3 cells | Histamine release in RBL-2H3 cells was reduced | Glycated fish protein hydrolysates reduced NO synthesis | [116] | |
| Purified great snakehead parvalbumin | 90 °C for 1, 2, 3 h | SDS-PAGE | The parvalbumin band intensity decreased as a function of heating time but was visible after 3 h heating | Parvalbumin maintained its typical structural properties after experiencing extensive thermal stroke | [117] | |
| Purified sardine parvalbumin | 70, 80, and 90 °C for 30, 60, and 120 min | Indirect non-competitive ELISA and dot blot | Rabbit anti-parvalbumin antibody | IgG binding to parvalbumin diminished 65% after 90 °C heating for 30 min | Heating was responsible for the reduction of antibody binding to purified sardine parvalbumin | [93] |
| Human IgE | 90% of patients showed reduced IgE binding, while 10% patients showed increased IgE binding | |||||
| Monkfish, Atlantic salmon, trout, pink ling, jewfish, pumpkin head trevally, swordfish, northern sand flathead, red gurnard, tiger flathead, and mosaic leatherjacket | 100 °C for 45 min | Western blot | Anti-carp mAb Anti-cod mAb |
Reduced IgG binding | [118] | |
| Pilchard, cod, dory, bright redfish, sea mullet, pink ling, barramundi, blue threadfin, cobia, crimson snapper, flame snapper, grunter bream, jewfish, pink snapper, pumpkin head trevally, sweetlip emperor, saddletail snapper, striped snapper, yellowfin bream, yellowtail scad, northern sand flathead, and red gurnard | 100 °C for 45 min | Western blot | Anti-carp mAb Anti-cod mAb |
Consistent IgG binding as the raw protein extracts | ||
| Coral trout, eastern school whiting, grass emperor, sand whiting, Spanish mackerel, yellowfin tuna, and tiger flathead | 100 °C for 45 min | Western blot | Anti-carp mAb Anti-cod mAb |
Increased IgG binding |
||
| Purified sardine parvalbumin | 90 °C for 1 h then pepsin digested for 30, 60, 120 min at pH 2, 37 °C | Indirect non-competitive ELISA and dot blot | Rabbit anti-parvalbumin antibody | Decreased IgG binding | Pepsin hydrolysis decreased the binding of IgG | |
| Human IgE | All IgE-binding capacity was eliminated completely | |||||
| Whiting protein extracts | Soak in vinegar for 30 min and then heat at 100 °C for 5 min | Indirect non-competitive ELISA and Western blot | Anti-fish tropomyosin mAb | IgG-binding capacity decreased significantly regardless of different types of vinegar | Acidic pH changed the immunoreactivity and detectability of whiting | [119] |
| Whiting, cod, and red grouper protein extracts | Soak in vinegar for different periods (<1 min, 15 min, 30 min, and 60 min) and then heat at 100 °C for 5 min | Indirect non-competitive ELISA and Western blot | Anti-fish tropomyosin mAb | Whiting: IgG immunoreactivity decreased significantly after 15 min treatment; cod and grouper: IgG immunoreactivity decreased significantly even within 1 min treatment | Acid pH either altered tropomyosin conformation or lowered its solubility | |
| Whiting, cod, and red grouper protein extracts | 100 °C for 5, 15, 30, and 60 min | Western blot | Human IgE | Prolonged vinegar cooking time significantly reduced the IgE immunoreactivity | Acid pH-induced protein denaturation | |
| Cod protein extracts | In vitro digestion at pH 1.25–5 | Western blot | Human IgE | When pH ≤ 2.5, all proteins lost IgE-binding capability within 1 min; when 2.5 < pH ≤ 5, IgE immunoreactivity was still observed after 1 h digestion | Gastric pH could digest and degrade cod proteins. Those patients with abnormal gastric pH may be exposed to an increased allergenicity | [120] |
| RAST inhibition | Human IgE | Digested cod proteins inhibited IgE binding as a function of time | ||||
| Histamine release assay | Histamine release was only observed at high concentration of digests | |||||
| Whiff protein extracts | 100 °C for 10 min | Western blot | Human IgE | More IgE-reactive bands were observed | [88] | |
| Whiff protein extracts | 100 °C for 10 min and then in vitro gastric digestion | Western blot | Human IgE | IgE bound to fragmented proteins even after 120 min; IgE binding to 24 kDa, 34 kDa, and 130 kDa proteins was weakened | Heating-induced protein degradation | |
| Purified whiff parvalbumin | 100 °C for 10 min and then in vitro gastric digestion | Western blot | Human IgE | Immunoreactive parvalbumin monomer disappeared after 5 s digestion while its dimer was visible after 120 min | Heating generated dimers that were partially stable towards gastric digestion | |
| Purified Alaska pollock parvalbumin | Glycation with glucose, fructose, ribose, lactose, and galactose at 60 °C, 65% for 1 h | Indirect competitive ELISA |
Rabbit antisera | Glycation with glucose and fructose enhanced both IgG and IgE binding, while glycation with ribose, lactose, and galactose decreased both IgG and IgE binding | Glycation changed protein conformation, which affected the specific recognition of antigen and antibody | [121] |
| Human IgE | ||||||
| Glass carp purified parvalbumin | Glycation with maltose | Indirect competitive ELISA | Rabbit anti-PV sera | Reduced IgG binding | Heat treatment was the major cause for decreased immunoreactivity | [36] |
| Human IgE | Suppressed IgE binding | Heat treatment and Maillard reaction led to the structural change of parvalbumin | ||||
| Recombinant silver cap parvalbumin | Glycation with glucose at 60 °C for 72 h | Dot blot | Human IgE | Decreased IgE binding | Glycation sites were partially located at IgE-binding epitopes | [122] |
| Rat basophilic leukemia assay | Reduced histamine release and secretion of IL-4 and TNF-α. | |||||
| Tuna | Canning | Double-blind placebo-controlled food challenge | All patients did not show sensitization and adverse reaction after consumption | Canning led to the formation of a homogenous mixture of different molecular weight fragments | [123] | |
| Immunoblot and indirect competitive ELISA | Human IgE | All sera showed minimal to absent IgE binding | ||||
| Salmon | Canning | Double-blind placebo-controlled food challenge | All patients did not show an adverse reaction after consumption | Canning led to a remarkable loss of definable protein bands on SDS-PAGE | ||
| Immunoblot and indirect competitive ELISA | Human IgE | Minimal IgE binding | ||||
| Haddock and rainbow trout | Hot smoking at 80–100 °C | Indirect competitive ELISA | Human IgE | 83.3% of patients showed increased IgE binding | Novel bands at around 65 kDa were observed on SDS-PAGE | [38] |
| Tuna | Canning at high temperature (116–121 °C) and pressure for up to 14 h | Indirect competitive ELISA | Human IgE | All patients showed decreased IgE binding | No parvalbumin band was visible on the SDS-PAGE | |
| Atlantic cod | Drying | Indirect competitive ELISA | Human IgE | All patients showed increased IgE binding | Several novel bands from 70 to > 188 kDa were observed on SDS-PAGE | [38] |
| Atlantic cod | Dried cod soaked in a pH 11–12 lye solution and subsequently in cold water | Indirect competitive ELISA | Human IgE | All patients showed reduced IgE binding | Parvalbumin band intensity on SDS-PAGE was reduced 48% | |
| Atlantic cod | Cod dried after salting | Indirect competitive ELISA | Human IgE | 58.3% of patients showed decreased IgE binding, while 33.3% patients showed increased IgE binding | Several novel bands from 70 to > 188 kDa were observed on SDS-PAGE | |
| Atlantic salmon | Cured in a mixture of sugar, spices, and salt | Indirect competitive ELISA | Human IgE | 80% of patients showed reduced IgE binding, while 20% of patients showed 65 times more IgE binding | Parvalbumin band intensity on SDS-PAGE was reduced by 34% | |
| Atlantic salmon | Cold smoking at 20–30 °C after being cured for a day | Indirect competitive ELISA | Human IgE | 80% of patients showed increased IgE binding | Novel bands at around 30 kDa were observed on SDS-PAGE | |
| Rainbow trout | Salted trout undergoes controlled enzymatic fermentation | Indirect competitive ELISA | Human IgE | 81.8% of patients showed decreased IgE binding, while 18.2% patients showed 30 times more IgE binding | Parvalbumin band intensity on SDS-PAGE was reduced by 40% | |
| Herring | Pickled herrings are prepared in an acetic acid–salt brine | Indirect competitive ELISA | Human IgE | 87.5% of patients showed decreased IgE binding | Few bands < 62 kDa were observed, and parvalbumin band intensity decreased on SDS-PAGE | |
| Salmon | Hydrolysis | Indirect competitive ELISA | Human IgE | Three patients showed more IgE binding | Absence of discernible bands and weak bands up to around 50 kDa | |
| Blue whiting | Hydrolysis | Indirect competitive ELISA | Human IgE | Two patients showed decreased IgE binding, while one patient showed more IgE binding | Absence of discernible bands and weak bands up to around 50 kDa | |
| Carp, catfish, chub mackerel, sardine, chinook salmon, albacore tuna, and mahi-mahi | Stored at −20 °C | Indirect non-competitive ELISA | IgG | A decrease in parvalbumin immunoreactivity was observed after 112-day storage, but parvalbumin was still considered stable at frozen stages | Less freeze-induced protein denaturation was observed in intact muscle. Frozen storage mainly altered myofibrillar proteins instead of sarcoplasmic proteins | [124] |
| Food-grade cod gelatin | Histamine release assay | 10% of patients showed histamine release | ||||
| Skin prick test | 23.3% of patients showed positive results | |||||
| Double-blind placebo-controlled food challenge | None of the patients showed allergic symptoms to 3.61 g fish gelatin | [125] | ||||
| Yellowfin tuna gelatin | Western blot | Human IgE | 3% of patients showed IgE binding | The manufacturing process eliminated the fish allergens | [32] | |
| Double-blind placebo-controlled food challenge | None of the patients showed allergic symptoms to 5 g fish gelatin |