Content and Availability of Minerals in Plant-Based Burgers Compared with a Meat Burger

Ci a ion: La unde-Dada, G.O.;
Kaja abille, N.; Rose, S.; A a sha,
S.M.; Kose, T.; Aslam, M.F.; Hall,
W.L.; Sha p, P.A. Con en and
A ailabili y o Mine als in
Plan -Based Bu ge s Compa ed wi h
a Mea Bu ge . Nu ien s 2023,15,
2732. h ps://doi.o g/10.3390/
nu15122732
Academic Edi o s: M. Luisa Bone
and Chia a Di Lo enzo
Recei ed: 30 Ap il 2023
Re ised: 7 June 2023
Accep ed: 8 June 2023
Published: 13 June 2023
Copy igh : © 2023 by he au ho s.
Licensee MDPI, Basel, Swi ze land.
This a icle is an open access a icle
dis ibu ed unde he e ms and
condi ions o he C ea i e Commons
A ibu ion (CC BY) license (h ps://
c ea i ecommons.o g/licenses/by/
4.0/).
nu ien s
A icle
Con en and A ailabili y o Mine als in Plan -Based Bu ge s
Compa ed wi h a Mea Bu ge
Gladys O. La unde-Dada 1,* , Na oa Kaja abille 1,2,3 , Sophie Rose 1, Sa ah M. A a sha 1, Tugba Kose 1,
Mohamad F. Aslam 1, Wendy L. Hall 1and Paul A. Sha p 1
1Depa men o Nu i ional Sciences, School o Li e Cou se Sciences, King’s College London,
F anklin-Wilkins-Building, 150 S am o d S ee , London SE1 9NH, UK; [email p o ec ed] (N.K.);
[email p o ec ed] (S.R.); [email p o ec ed] (S.M.A.); [email p o ec ed] (T.K.);
[email p o ec ed] (M.F.A.); wendy[email p o ec ed] (W.L.H.); [email p o ec ed] (P.A.S.)
2Depa men o P e en i e Medicine and Public Heal h, Uni e si y o he Basque Coun y (UPV/EHU),
01006 Vi o ia, Spain
3
Nu i ion and Obesi y G oup, Depa men o Pha macy and Food Science, Lucio Lasca ay Resea ch Ins i u e,
Uni e si y o he Basque Coun y (UPV/EHU), 01006 Vi o ia, Spain
*Co espondence: [email p o ec ed]
Abs ac :
Inc easing numbe s o indi iduals ollow plan -based die s. This has spa ked in e es in
he nu i ional e alua ion o he mea subs i u e sec o . Nu i ional unde s anding o hese p oduc s
is i al as plan -based ea ing becomes mo e common. Fo example, animal p oduc s a e ich sou ces
o i on and zinc, and plan -based oods could be inadequa e in hese mine als. The main aim was o
analyse he mine al composi ion and abso p ion om a ange o plan -based mea - ee bu ge s and
compa e hem o a ypical bee bu ge . To al and bioaccessible mine al con en s o plan -based bu ge s
and a bee bu ge we e de e mined using mic owa e diges ion and
in i o
simula ed gas oin es inal
diges ion, espec i ely. Mine al bioa ailabili y was analysed by
in i o
simula ed gas oin es inal
diges ion o oods, ollowed by exposu e o Caco-2 cells o he sample diges s and assessmen o
mine al up ake. Mine al quan i ica ion o all samples was achie ed using induc i ely coupled
ICP-op ical emission spec ome y (ICP-OES). The con en o mine als a ied signi ican ly amongs
he bu ge s. Signi ican ly g ea e quan i ies o Fe and Zn we e ound in he bee bu ge compa ed o
mos mea subs i u es. Bioaccessible Fe was signi ican ly highe in he bee compa ed o mos o he
plan -based mea al e na i es; howe e , bioa ailable Fe o mos plan -based bu ge s was compa able
o bee (p> 0.05). Simila ly, bioaccessible Zn was signi ican ly (p< 0.001) highe om he bee bu ge .
Mo eo e , bee was supe io ega ding bioa ailable Zn (p
≤
0.05–0.0001), wi h only he mycop o ein
bu ge displaying compa able Zn bioa ailabili y (p> 0.05). Bee is an excellen sou ce o bioaccessible
Fe and Zn compa ed o mos plan -based subs i u es; howe e , hese plan -based subs i u es we e
supe io sou ces o Ca, Cu, Mg and Mn. The quan i y o bioaccessible and abso bable Fe a ies
d ama ically among he mea al e na i es. Plan -based bu ge s ha e he po en ial o p o ide adequa e
quan i ies o i on and zinc o hose consuming such bu ge s as pa o a a ied die . Thus, guiding
consume choices will depend on he a ie y o he ege able cons i uen s and hei i on nu i ional
quali y in di e en bu ge s.
Keywo ds: i on; bu ge s; plan ; bioaccessibili y; bioa ailabili y
1. In oduc ion
To mee he Uni ed Na ions Sus ainable De elopmen Goals and Pa is Ag eemen ,
i may be necessa y o global die s o shi o emb ace g ea e eliance on plan -based
oods. Acco ding o he EAT-Lance Commission, o help mee global a ge s by 2050, a
die a y pa e n ha is heal hy o bo h people and plane should double he consump ion o
ui s, ege ables, legumes and nu s, and educe by 50% he consump ion o added suga s
and ed mea [
1
]. These p ac ices could suppo en i onmen al sus ainabili y, alongside
Nu ien s 2023,15, 2732. h ps://doi.o g/10.3390/nu15122732 h ps://www.mdpi.com/jou nal/nu ien s
Nu ien s 2023,15, 2732 2 o 11
po en ial heal h bene i s o he popula ion. Fo ins ance, hose who choose o ollow a
ege a ian o egan die a e epo ed o ha e a lowe isk o ca dio ascula disease, ype 2
diabe es, and obesi y [
2
]. In gene al, hough i on s o es o ege a ians may be low, anaemia
incidences may no di e signi ican ly om hose o omni o es [
3
]. Hence, a well-planned
a ied ege a ian die could main ain op imal i on nu i ion in he populace. In addi ion, a
plan -based die appea s o be bene icial o human heal h by p omo ing he de elopmen
o mo e di e se and s able mic obial gu popula ions [4].
Al hough ege a ian and egan die s ha e been claimed o ha e a a ie y o posi i e
heal h e ec s, he e is much deba e abou whe he hey can ma ch an omni o ous die
in e ms o nu ien in ake [
5
]. Mine als o conce n a e calcium, i on, and zinc, as well as
i amin B12, i amin D, and omega-3 a y acids [
6
]. As hese mic onu ien s a e ound
abundan ly in animal-de i ed p oduc s, ege a ian and egan die s mus be p ope ly
guided o a oid nu i ional de iciencies.
I on de iciency is he mos common mine al insu iciency wo ldwide and is es ima ed
o a ec wo billion people globally [
7
,
8
]. The impo ance o i on canno be unde s a ed,
as i on inadequacy can ha e de as a ing and i e e sible consequences, such as impai ed
cogni i e de elopmen du ing childhood [
9
]. Those on a ege a ian o egan die , a e a
a isk o i on de iciency i hey do no ollow p o essional die a y guidelines, because he
i on ob ained is p edominan ly in he o m o nonheme i on [
10
]. On he o he hand, an
omni o ous die con ains a combina ion o heme ( om mea and ish p oduc s) as well
as nonheme i on ( om plan p oduc s). Heme i on is abso bed mo e e icien ly om a
human die (20–30%) han nonheme i on (5–15%); hus, heme i on demons a es g ea e
bioa ailabili y [11].
The bioa ailabili y o nonheme i on a ies in di e en oods, and his is la gely
in luenced by endogenous cons i uen inhibi o s and p omo o s wi hin hese oods. The
main inhibi o o i on abso p ion is phy ic acid, whils polyphenols, annins, calcium, and
soy also play inhibi o y oles [
12
,
13
]. In con as , asco bic acid, mea , and ci ic acid a e
all enhance s o i on abso p ion [
14
]. Asco bic acid in he die educes e ic i on in o
e ous i on, which has a g ea e capaci y o abso p ion [
15
]. In addi ion o i on, a la ge
p opo ion o zinc is de i ed om animal p oduc s, wi h mea cons i u ing a hi d o
he zinc in ake in UK die s (Na ional Die and Nu i ion Su ey NDNS) [
16
]. As mea is
elimina ed om he die , i is eplaced by an inc ease in phy a e- ich oods such as legumes
and wholeg ains, which can ha e nega i e e ec s on he abili y o abso b bo h mine als.
Thus, while hose ollowing ege a ian o egan die s can acqui e mine als om plan
p oduc s, hei abso p ion is la gely inhibi ed by phy ic acid [17].
The change in consume needs, i.e., he g ea e equi emen o ege a ian and egan
ood p oduc s, has no gone unno iced by e aile s in he UK. The ege a ian and egan
ma ke has expe ienced subs an ial g ow h, pa icula ly in he eady meals and con enience
ood sec o s [
5
]. I is es ima ed ha mea analogues con ibu e signi ican ly o human die s
which exclude animal lesh and hei de i a i es [
18
]. Mea -al e na i e p oduc s a e aimed
p ima ily a ege a ians, egans, pesce a ians, o lexi a ians, as well as hose seeking
o di e si y hei die s [
19
]. Mea subs i u es a e la gely based on soya, mycop o ein,
ege ables, whea de i a i es, and pulses [
20
,
21
]. These mea analogues o en mimic
p oduc s adi ionally p epa ed om animals, as hey can be manu ac u ed in o bu ge ,
mea ball, and sausage o ma s.
Plan -based mea subs i u es as eady meal p oduc s a e also widely consumed by
adul s due o hei con enience as con olled po ions (single se ings help consume s
manage hei meal in ake) and easy cooking by mic owa e, and hey o e a a ie y o
choices o ood ypes. These p oduc s ha e been epo ed o be nu i ionally adequa e, as
well as ha ing some sho alls [
22
–
24
]. Fo example, a a a bean p o ein subs i u e o bee
o ish exhibi ed educed i on bioa ailabili y in heal hy emales [25].
The e a e limi ed da a assessing whe he plan -based mea al e na i es can ma ch he
high mine al p o ile o compa able non ege a ian meals, and his could ha e impo an
implica ions on he mine al s a uses o indi iduals who do no consume mea p oduc s.
Nu ien s 2023,15, 2732 3 o 11
A ising om his, he main pu pose o his s udy was o assess whe he plan -based bu ge s
can compa e wi h he mine al con en and bioa ailabili y o hei mea -based equi alen s
o in o m consume s abou hei choices. Consequen ly, he s udy de e mined he mine al
con en and bioaccessibili y and bioa ailabili y o i on and zinc as a no el app oach, in
bo h ege a ian and egan bu ge s, and compa ed hem o hose o a bee bu ge .
2. Ma e ials and Me hods
2.1. Reagen s and Chemicals
Unless o he wise s a ed, all he eagen s and chemicals used in his s udy we e pu -
chased om Sigma-Ald ich L d. (Do se , UK). Solu ions o enzymes (pepsin and panc a ic-
bile ex ac ) we e all eshly p epa ed jus be o e use.
2.2. Sample Collec ion and P epa a ion
Bu ge samples we e sou ced om a majo supe ma ke in he UK. Samples we e
cooked as pe he manu ac u e s’ ins uc ions using an o en o a g ill. Each bu ge (50 g)
was placed in an aluminium dish, ozen a
−
20
◦
C, and eeze-d ied o i e days using a
eeze d ye (CHRIST ALPHA 1-4 L Dplus SciQuip L d, New own, UK). D ied samples
we e g ound in a blende o ob ain a ine powde , s o ed in sealed bags, and kep a 5 ◦C.
2.3. Mois u e Con en Analysis
To de e mine he d y ma e , 5 g o each bu ge was placed in a c ucible and d ied in
an o en a 65
◦
C o 48 h un il cons an weigh was a ained and ans e ed o desicca-
o s. D ied samples we e eweighed, and mois u e con en was calcula ed. The da a a e
p esen ed as means n= 5 ±SEM.
2.4. To al Mine al Con en o Samples
The o al mine al con en o each sample was de e mined by induc i ely coupled
plasma-op ical emission spec oscopy (ICP-OES) (MS) a e mic owa e diges ion as de-
sc ibed [
26
]. Essen ially, 0.5 g o each sample was placed in o diges ion o which 10 mL
o 70% 1 M HNO
3
was added. Tubes we e loaded in o a MARS 6 mic owa e diges ion
sys em (CEM Mic owa e Technology L d., Buckingham, UK) and he empe a u e was
aised o 210
◦
C o 45 min, and hen cooled o oom empe a u e. Fo ICP-OES, samples
we e decan ed in o ubes and 140
µ
L o 1 ppm y ium was added; he ea e , he olume
was made up o 14 mL using Milli-Q wa e . Fo ICP-MS, 50
µ
L o each sample was added
o a solu ion consis ing o 4.9 mL Milli-Q wa e and 50
µ
L o 5 ppm gallium. The da a a e
p esen ed as means n= 5 ±SEM.
2.5. In Vi o Simula ed Gas oin es inal Diges ion o Samples
An
in i o
simula ed enzyma ic diges ion o samples was employed o mimic gas-
oin es inal condi ions and assess bioaccessibili y o mine als [
27
–
29
]. In b ie , 0.5 g o
sample was mixed wi h 10 mL o saline solu ion (140 mM NaCl; 5 mM KCl, pH 2.0) and le
o 15 min in he da k (20
◦
C). The pH was adjus ed (HANNA Ins umen ) o 2.0 using 1 M
HCl, and 0.5 mL o pepsin (16 mg/mL) om po cine gas ic mucosa was added. Samples
we e incuba ed o 90 min in he da k a 37
◦
C on a ocking pla o m (S ua Scien i ic
Shake ) se o 150 pm. The pH was hen al e ed o 7.0 using 1 M NaHCO
3
be o e adding
2.5 mL po cine bile and panc ea in ex ac s (8.5 mg/mL bile; 1.4 mg/mL panc ea in) was
added. Volumes we e aised o 15 mL using pH 7.0 saline solu ion and hen incuba ed on
he ocking pla o m as desc ibed ea lie . The ea e , samples we e cen i uged (Eppendo
Cen i uge 5804R, Sigma) a 5000 pm o 10 min. Supe na an s we e decan ed and il e ed
o e nigh in he da k a 5
◦
C using Wha man 540 il e pape , and il a es we e s o ed a
−
20
◦
C un il used. The p ocedu e was also pe o med o sham con ols o which no ood
sample was added. The da a a e p esen ed as means n= 3 ±SEM.
Nu ien s 2023,15, 2732 4 o 11
2.6. Mine al Up ake by Caco-2 Cells
Caco-2 cells we e seeded in o six-well pla es and g own o 14 days unde he con-
di ions o allow o ull di e en ia ion. On he day be o e expe imen a ion, he cul u e
medium was disca ded and eplaced wi h 2 mL/well o se um- ee RPMI-1640 medium.
The nex day, diges s we e de os ed, hea ed o 100
◦
C o 5 min o inac i a e enzymes, and
hen cen i uged o 5 min a 5000 pm (Eppendo Cen i uge 5804R, Sigma). Cell medium
was emo ed and eplaced wi h 2 mL/well o wo king solu ion, which consis ed o 1 pa
diges o 1 pa se um- ee medium. Cells we e incuba ed o 1 h o ICP-OES analysis and
4 h o ICP-MS analysis (5% CO2; 37 ◦C).
Fo ICP-OES analysis, wo king solu ions we e emo ed, wells we e washed wice
wi h Ve sene, and 500
µ
L/well o 50 mM NaOH was added. Pla es we e placed on a
ocking pla o m a 20
◦
C o 2 h. Fo lysis, cells we e subjec ed o 45 min o sonica ion
using a hea ed (40
◦
C) ul asonic ba h (FB 11021, Fishe b and). To adjus o a iabili y
in cell numbe be ween samples, 20
µ
L aliquo s o each lysa e we e ans e ed o 96-well
pla es o p o ein quan i ica ion. The emaining lysa es we e desicca ed o 2 h a 60
◦
C
using a acuum-in eg a ed cen i ugal concen a o o minimise a ia ions due o olume
di e ences (miVAC DNA-23050-A00, Gene ac). D ied lysa es we e mixed wi h 250
µ
L
o 65% HNO
3
, and hen 200
µ
L aliquo s we e made up o 6 mL using 17% HNO
3
(which
con ained 1.0175 mL o 1000 ppm y ium pe 1 L o acid). Samples we e diges ed a 80
◦
C
o 12 h and le o cool be o e analysis by ICP-OES. The da a a e p esen ed as means
n= 4 ±SEM.
2.7. P o ein Analysis
A Bio-Rad p o ein assay ki (Bio-Rad Labo a o ies, UK) was u ilised o de e mine
he p o ein om Caco-2 cell lysa e. To a 96-well mic o i e pla e, 20
µ
L o he sample,
20
µ
L o eagen A + S (1 mL o solu ion A added o 20 mL), and 160
µ
L o eagen B
we e added. Bo ine se um albumin was used as a s anda d. The pla e was incuba ed a
oom empe a u e on a pla o m shake o 10 min and abso bance was ead a 750 nm. A
s anda d cu e was plo ed, and p o ein con en was ex apola ed and calcula ed.
2.8. S a is ical Analysis
Da a we e analysed using Mic oso O ice Excel 2017 and G aphPad P ism 8.0. Da a
a e exp essed as mean
±
s anda d e o o he mean (SEM). Compa isons o means we e
analysed by one-way analysis o a iance (ANOVA). Dunne ’s pos -hoc es was used o
mul iple compa isons, wi h bee se as he con ol g oup. Di e ences we e signi ican when
p< 0.05.
3. Resul s
3.1. Mois u e and Mine al Composi ion o Bu ge Samples
The ing edien composi ions o all bu ge s di e ed, and hese a e shown in Table 1. The
main ege able-based cons i uen s o he samples a e as ollows: A (pumpkin), B (bee oo ),
C (mycop o ein), D ( ed cabbage), E (jack ui ), F (po a o), G (soy), H (mush oom), and I
(bee ). The mois u e con en o aw bu ge s anged om 50.5% o 77.9%, whils cooked
bu ge s anged be ween 47.8% and 75.2% (Table 2). Ca, Cu, Fe, Mg, Mn, and Zn con en
we e es ima ed in he samples. Signi ican di e ences in mine al con en s we e obse ed
be ween he plan -based bu ge s e sus he bee bu ge (Table 2). O e all, he plan -based
bu ge s con ained highe amoun s o Ca, Mg and Mn, whe eas bee bu ge s had lowe Cu
con en s (Table 2).
Nu ien s 2023,15, 2732 5 o 11
Table 1. Ing edien composi ion o bu ge samples.
Sample Ing edien Lis
APumpkin (50%), swee po a o, soya p o ein, sun lowe oil, po a o s a ch, me hyl cellulose, co iande , u me ic,
whi e peppe , cumin, enug eek, whea ib e, sal , pap ika powde , onion powde , ga lic powde , ed pap ika
BBee oo (80%), po a o s a ch, onion, soya p o ein, whea ib es, me hyl cellulose, sal , po a o p o ein, ga lic
pu ée
C
Mycop o einTM (38%), ex u ed whea p o ein (whea lou , sodium algina e, plain ca amel), ehyd a ed ee
ange egg whi e, ege able oil, onion, smoked yeas , po assium chlo ide, milk p o eins, oas ed ba ley, calcium
chlo ide, calcium ace a e
D
Red cabbage, black u le beans, b eadc umbs (whea lou , calcium ca bona e, i on, niacin, hiamin), sun lowe
oil, sal , yeas , osema y, soya p o ein concen a e, sushi ice, ca o , ice inega , wa e , onion, da k soya sauce,
bee oo , apeseed oil, ed chilli pu ée, ed miso, maple sy up, ga lic, black peppe
E
Jack ui (45%), wa e , ice lou , g am lou , maize lou , maize s a ch, yeas ex ac , b own suga , oma o pas e,
co n lou , po a o s a ch, sal , sun lowe oil, ed peppe , spi i inega , musco ado suga , cide inega , pa sley,
onion powde , ga lic powde , lemon powde , sodium bica bona e, disodium diphospha e, pap ika, cane
molasses, g ape inega , ennel seed, cayenne peppe , cumin, co iande , osema y, dex ose monohyd a e,
peppe , xan han gum, black eacle, ama ind pas e, pimen o, ginge , clo es
F
Po a o (15%), aube gine, onion, len ils, apeseed oil, e a, sp ing onion, chickpeas, swee po a o, egg, co n lou ,
po a o s a ch, whea lou , calcium ca bona e, i on, niacin, hiamin, ga lic pu ée, ed chilli pu ée, pa sley, min ,
sal , cumin, ex a i gin oli e oil, oma o pu ée, peppe , co iande , pap ika, yeas
G
SOY s uc u e (Wa e , soya p o ein, whea s a ch, whea p o ein) (64%), b oad beans, sun lowe oil, palm oil,
onion powde , peppe , ga lic, ginge , mace, onion, clo e, co iande , o egano, me hyl cellulose, bamboo ib e,
apioca s a ch, seaweed, sal , i on, i amin B12
HWa e , mush ooms (32%), whea glu en, pea lou , whea lou , ege able sue , pea ib e, me hylcellulose, pea
s a ch, sal , onion, yeas , peppe , sodium me abisulphi e
IBee (95%), onion, sal , bu e , peppe , sodium sulphi e, sodium asco ba e
Vege a ian: C, F, & G; Vegan: A, B, D, E, & H; Animal: I. Ing edien lis was ep oduced om labels on he bu ge
samples pu chased om a supe ma ke in he UK.
Table 2.
Mean mois u e and mine al con en s o ege a ian, egan, and bee bu ge s (mg/100 g) d y
weigh .
Sample Mois u e (%) Fe Ca Cu Mg Mn Zn
A67.9 3.36 ±0.03 134 ±0.93 *** 0.43 ±0.01 *** 85.9 ±0.34 *** 1.20 ±0.12 *** 1.10 ±0.02 ***
B75.2 3.39 ±0.06 156 ±1.38 *** 0.42 ±0.01 *** 94.1 ±0.70 *** 1.88 ±0.01 *** 1.67 ±0.03 ***
C62.2 1.13 ±0.04 *** 260 ±7.01 *** 0.56 ±0.01 *** 50.5 ±0.54 *** 3.25 ±0.04 *** 7.15 ±0.08 *
D54.3 2.70 ±0.05 *** 93.4 ±1.39 *** 0.33 ±0.00 *** 70.4 ±0.96 *** 0.97 ±0.01 *** 1.14 ±0.04 ***
E57.1 1.27 ±0.03 *** 31.7 ±0.10 *** 0.24 ±0.00 *** 40.1 ±0.20 *** 0.63 ±0.00 *** 0.89 ±0.02 ***
F47.8 1.99 ±0.08 *** 57.9 ±0.92 *** 0.23 ±0.00 *** 39.5 ±0.34 *** 0.47 ±0.01 *** 0.91 ±0.03 ***
G53.6 14.5 ±0.03 *** 150 ±1.32 *** 0.28 ±0.00 *** 62.5 ±0.46 *** 0.87 ±0.01 *** 1.14 ±0.01 ***
H61.2 2.90 ±0.02 *** 46.2 ±0.28 *** 0.43 ±0.00 *** 44.5 ±0.15 *** 0.83 ±0.01 *** 2.24 ±0.01 ***
I54.1 3.42 ±0.01 9.59 ±0.21 0.14 ±0.00 37.2 ±0.12 0.07 ±0.00 7.41 ±0.06
Mine al con en quan i ied by ICP-OES. The main ing edien s ep esen ed by he sample coding a e as ollows: A:
Pumpkin, B: Bee oo , C: Mycop o ein, D: Red cabbage, E: Jack ui , F: Po a o, G: Soy, H: Mush oom, I: Bee . Da a
exp essed as mean
±
SEM (n= 5). A one-way ANOVA and Dunne ’s es we e pe o med o de e mine signi ican
di e ences o bee . * Signi ican a he 0.05 p obabili y le el; *** Signi ican a he 0.001 p obabili y le el.
The ing edien composi ions o all bu ge s a ied, and hese a e shown in Table 1. The
i s p ocedu e was he de e mina ion o he mois u e con en o each bu ge , and hese
anged be ween 47.8% and 75.2% (Table 2). Signi ican di e ences in mine al con en we e
obse ed be ween he ege a ian and egan bu ge s e sus he bee bu ge (Table 2). The
bee bu ge had signi ican ly (p< 0.001) highe le els o i on han mos mea al e na i es,
excep o pumpkin and bee oo , which did no each signi icance. The soy bu ge had
signi ican ly highe (p< 0.001) Fe han he bee bu ge (Table 2). Fu he mo e, he Zn
con en was signi ican ly (p< 0.001) highe in he bee bu ge compa ed o all he mea

Nu ien s 2023,15, 2732 6 o 11
subs i u es. All mea al e na i es had signi ican ly (p< 0.001) highe le els o Ca, Cu, Mg,
and Mn han he bee bu ge s (Table 2).
3.2. I on and Zinc Bioaccessibili y om Bu ge Samples
A well-es ablished
in i o
me hod was employed o es ima e he bioaccessibili y o
mine als om bu ge samples. Fe bioaccessibili y was signi ican ly g ea e om he bee
bu ge han all o he aw bu ge samples excep o soy and pumpkin samples (Figu e 1A).
To al bioaccessible Zn was signi ican ly (p< 0.001) highe om he bee bu ge han all
o he bu ge samples (Figu e 1B).
Nu ien s2023,15,xFORPEERREVIEW6o 13
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
2).Thebee bu ge hadsigni ican ly(p<0.001)highe le elso i on hanmos mea al e -
na i es,excep  o pumpkinandbee oo ,whichdidno  eachsigni icance.Thesoy
bu ge hadsigni ican lyhighe (p<0.001)Fe han hebee bu ge (Table2).Fu he mo e,
heZncon en wassigni ican ly(p<0.001)highe in hebee bu ge compa ed oall he
mea subs i u es.Allmea al e na i eshadsigni ican ly(p<0.001)highe le elso Ca,Cu,
Mg,andMn han hebee bu ge s(Table2).
3.2.I onandZincBioaccessibili y omBu ge Samples
Awell-es ablishedin i ome hodwasemployed oes ima e hebioaccessibili yo 
mine als ombu ge samples.Febioaccessibili ywassigni ican lyg ea e  om hebee 
bu ge  hanallo he  awbu ge samplesexcep  o soyandpumpkinsamples(Figu e
1A).To albioaccessibleZnwassigni ican ly(p<0.001)highe  om hebee bu ge  han
allo he bu ge samples(Figu e1B).

(A)
Nu ien s2023,15,xFORPEERREVIEW7o 13
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

(B)
Figu e1.(A):I onbioaccessibili y ombu ge s.Aone-wayANOVAandDunne ’s es we epe -
o med ode e minesigni ican diffe ences obee wi hsigni icancedisplayedas ollows:p≤0.05
(*),≤0.01(**),≤0.001(***),and≤0.0001(****).Da a ep esen means(n=3)±SEM.(B):Zincbioacces-
sibili y ombu ge s.Aone-wayANOVAandDunne ’s es we epe o med ode e minesigni i-
can diffe ences obee wi hsigni icancedisplayedas≤0.0001(****).Da a ep esen means(n=3)±
SEM.
3.3.Mine alUp ake omPlan ‐BasedBu ge Diges sbyCaco‐2Cells
Mine albioa ailabili yisaquan i ica iono  hele elo mine als akenupbycells
a e aspeci iedpe iodo exposu e.He e,mine albioa ailabili ywases ima edbyap-
plying hein i odiges edsamples oCaco-2cells.Febioa ailabili y o allplan -based
bu ge swascompa able o hebee bu ge (I),wi h heexcep ionso  hebee oo bu ge s,
whichwe esigni ican lylowe (Figu e2A).Theplan -basedbu ge shadsigni ican lyless
Znup ake hanbee ;howe e , hemycop o einbu ge (C)was heonlyplan -based
bu ge wi hcompa ableZnbioa ailabili y(Figu e2B).
Figu e 1.
(
A
): I on bioaccessibili y om bu ge s. A one-way ANOVA and Dunne ’s es we e pe -
o med o de e mine signi ican di e ences o bee wi h signi icance displayed as ollows:
p≤0.05 (*)
,
≤
0.01 (**),
≤
0.001 (***), and
≤
0.0001 (****). Da a ep esen means (n= 3)
±
SEM. (
B
): Zinc bioaccessi-
bili y om bu ge s. A one-way ANOVA and Dunne ’s es we e pe o med o de e mine signi ican
di e ences o bee wi h signi icance displayed as
≤
0.0001 (****). Da a ep esen means (
n= 3) ±SEM
.
Nu ien s 2023,15, 2732 7 o 11
3.3. Mine al Up ake om Plan -Based Bu ge Diges s by Caco-2 Cells
Mine al bioa ailabili y is a quan i ica ion o he le el o mine als aken up by cells a e
a speci ied pe iod o exposu e. He e, mine al bioa ailabili y was es ima ed by applying
he
in i o
diges ed samples o Caco-2 cells. Fe bioa ailabili y o all plan -based bu ge s
was compa able o he bee bu ge (I), wi h he excep ions o he bee oo bu ge s, which
we e signi ican ly lowe (Figu e 2A). The plan -based bu ge s had signi ican ly less Zn
up ake han bee ; howe e , he mycop o ein bu ge (C) was he only plan -based bu ge
wi h compa able Zn bioa ailabili y (Figu e 2B).
Nu ien s2023,15,xFORPEERREVIEW8o 13
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
(A)

(B)
Figu e 2.
(
A
): I on bioa ailabili y in Caco-2 cells om bu ge s. A one-way ANOVA and Dunne ’s es
we e pe o med o de e mine signi ican di e ences o bee wi h signi icance displayed
p≤0.05 (*)
,
≤
0.01 (**),
≤
0.001 (***), and
≤
0.0001 (****). Da a ep esen means (n= 4)
±
SEM. (
B
): Zinc bioa ailabil-
i y in Caco-2 cells om bu ge s. A one-way ANOVA and Dunne ’s es we e pe o med o de e mine
signi ican di e ences o bee wi h signi icance displayed as
≤
0.0001 (****). Da a ep esen means
(n= 4) ±SEM.
Nu ien s 2023,15, 2732 8 o 11
4. Discussion
Wi h mea analogues accoun ing o app oxima ely 1–2% o he o al mea ma ke and
inc easing by 15% annually in he UK, hei consump ion, composi ion, and nu i ional
con en equi e u he in es iga ion [
30
]. The cu en s udy in es iga ed he con en and
a ailabili y o mine als om a selec ion o mea subs i u es sold in he UK. The o al mine al
con en and
in i o
a ailabili y o Fe and Zn we e assessed in he samples. O e all, while
i on bioa ailabili y was compa able o mos plan -based and bee bu ge s, zinc a ailabili y
o he plan -based bu ge s was lowe han o bee .
As expec ed, signi ican a iabili y was obse ed in he mine al con en ac oss mea
subs i u es due o a wide a ie y o ing edien s used in he o mula ion (Table 1). The
mine al con en o bu ge samples was ound o be simila o hose desc ibed in ables
om [
31
]. The soy-based bu ge con ained ex emely high le els o i on (14.5 mg Fe/100 g),
which is ~4.2- old highe han ha quan i ied o bee . A ecen audi o 50 aw mea -
subs i u e bu ge s on he Aus alian ma ke ound ha hey con ained an a e age o 3.6 mg
Fe/100 g [
32
]. Va ying Fe le els could be a ibu ed o di e en cul i a ion condi ions
o plan componen s wi hin he mea subs i u es, p oduc de elopmen p ac ices, and
p ocessing egimens due o whea lou componen s o he bu ge s (which is o i ied by
law in he UK wi h i on bu no in Aus alia) [33].
To al zinc con en was signi ican ly lowe in plan -based bu ge s (excluding he myco-
p o ein bu ge ) compa ed o he bee bu ge . This esul is consis en wi h he li e a u e,
epo ing highe o al zinc con en in g ound bee han in plan -based al e na i es [
34
,
35
].
The da a on mycop o ein a e also suppo ed by showing ha mycop o ein con ains compa-
able amoun s o zinc o ha ound in mea [36,37].
Swing e al. [
35
] quan i ied mine al le els in a ious cooked plan -based bu ge s,
compa ing hem o po k and bee bu ge s. The esul s indica ed ha he plan -based
bu ge s had signi ican ly g ea e i on and zinc con en s han he animal-based bu ge s. This
con as s wi h he cu en s udy, which showed plan -based bu ge s con ained signi ican ly
lowe i on and zinc con en s compa ed o he bee bu ge s. This disc epancy may be ela ed
o he di e ences in he bu ge componen s be ween he wo s udies. Swing e al. [
35
]
analysed mock mea bu ge s such as ‘Beyond Mea ’, which we e made wi h a a ie y o
ing edien s. In e es ingly, he epo did no e ha soy-based bu ge s con ained he highes
o al i on a 36.3 ppm, compa ed o jus 19.4 ppm o bee .
Ou cu en s udy ound ha all mea al e na i es ha e highe calcium le els com-
pa ed o bee . This could be explained by se e al ac o s, such as he po en ial addi ion
o calcium chlo ide o plan bu ge s as a i ming agen , he o i ica ion o whea lou
wi h calcium, and bee being a poo sou ce o calcium (Na ional Die and Nu i ion Su ey
NDNS, [
16
]. This sugges s ha mea subs i u es could be an impo an sou ce o calcium
o hose who do no consume mea , ish, o dai y p oduc s.
The bee bu ge had signi ican ly g ea e i on bioaccessibili y han mea subs i u es,
wi h he no able excep ion o soy (Figu e 1A). This could be explained in pa by he soy
bu ge being o i ied wi h i on. Soy has been epo ed o lowe i on bioaccessibili y, due
o encapsula ion o i on wi hin la ge pep ide agg ega es du ing
in i o
diges ion [
38
].
None heless, o i ica ion o soy alongside an adequa e quan i y o asco bic acid may
pa ially o e come he inhibi o y e ec on i on bioaccessibili y [
39
]. In addi ion, he baking
p ocesses ca ied ou on he bu ge s may also pa ially e e se soy inhibi ion o i on [40].
Animal lesh is he p ima y sou ce o zinc in UK omni o ous die s and ep esen s
a sou ce o highly bioa ailable zinc [
41
,
42
]. Pe haps unsu p isingly, zinc bioaccessibili y
om he bee bu ge was signi ican ly g ea e han om he mea subs i u es ollowing
in i o diges ion (Figu e 1B).
Su p isingly, o mos o he plan -based bu ge s, i on bioa ailabili y did no di e
signi ican ly om bee (Figu e 2A). This may be ela ed o he addi ional ood componen s
p esen in he a ious bu ge s. Fo example, soy, which has a na u ally high i on con en ,
is an ing edien in se e al o he plan -based bu ge s. Fu he mo e, i on (added as a
o i ican ) is also lis ed in he ing edien s o some bu ge s. This sugges s ha a die ha
Nu ien s 2023,15, 2732 9 o 11
excludes animal p oduc s could achie e adequa e in akes o mine als om plan oods;
howe e , con en is a ela i ely poo p edic o o bioa ailabili y [
43
,
44
]. Thus, o al mine al
con en may no co ela e wi h mine al bioaccessibili y and bioa ailabili y.
Only he mycop o ein bu ge exhibi ed compa able zinc up ake o bee in Caco-2 cells
(Figu e 2B). Mycop o ein p oduc s ha e been epo ed o con ain high zinc con en s (wi h
a median con en o 6.7 mg/100 g) and had e y low con en o phy a e. This sugges s
ha mycop o ein, which is al eady a dominan mea subs i u e componen o egans and
ege a ians, is equally as e ec i e as bee in supplying adequa e zinc amoun s in he die s.
Plan ood p oduc s a e known o con ain high le els o phy a e, which can educe
i on and zinc up ake om plan -based bu ge s [
45
,
46
]. The inhibi o y e ec o phy a e is
po en ia ed by o ming mine al-calcium-phy a e complexes o low solubili y in he in es i-
nal lumen [
17
]. Fu he mo e, he high phy a e con en in soy p oduc s, alongside high
die a y calcium in ake, has been shown o lowe zinc bioa ailabili y in a s [
38
]. How-
e e , in humans, eplacing mea by 25% wi h soy did no impac mine al abso p ion [
47
].
This inding migh be p omising i mea educ ion is o be encou aged. Howe e , o al
eplacemen o mea wi h soy led o signi ican ly lowe abso p ion le els o zinc showing
ha he exclusion o mea may exace ba e poo bioa ailabili y o zinc om plan -de i ed
sou ces in ege a ian and egan die s [
47
]. A ecen s udy es ima ed he bioa ailabili y o
i on and zinc based on he phy a e:mine al mola a io, om samples o mea subs i u es
bough om con enience s o es in Go henbu g, Sweden [
48
]. None o he p oduc s we e
conside ed as sou ces o good mine al bioa ailabili y due o e y high con en o phy a e.
The s udy he e o e concluded ha he mea subs i u es analyzed did no con ibu e signi -
ican ly o abso bed i on. The a ia ions in ing edien s be ween he plan -based bu ge s,
as well as he p esence and in e ac ion o inhibi o s and enhance s in he bu ge s, can
in luence mine al bioa ailabili y and p o ide insigh o u u e in es iga ions. Cu en
die a y guidelines ecommend a educ ion in ed and p ocessed mea consump ion and an
inc ease in ui and ege able in ake o dec ease he isk o ch onic disease. The e o e, as
he popula ion mo es mo e owa ds he consump ion o a plan -based die , he exploi a ion
o he syne gy among die a y componen s o enhance i on abso p ion by he inco po a ion
o po en enhance s o mine al abso p ion in plan bu ge s becomes inc easingly impo an .
The composi ion o he as a ay o ege a ian and egan bu ge s is cons an ly
changing and de eloping due o echnological ad ances. The e o e, i is challenging
o assess and compa e he mine al con en and bioa ailabili y o he di e en p oduc s
cu en ly a ailable in he UK. Bu ge s a e no ea en in isola ion, bu o en as pa o a
mo e complex meal. Consequen ly, depending on he a ie y o ege able cons i uen s o
plan -based bu ge s, hey could p o ide adequa e quan i ies o i on and zinc in he die .
A limi a ion o he cu en wo k is ha cul u ed cell models may no e lec ue
physiological esponses. Howe e , Caco-2 cells ha e been alida ed and e i ied o he
de e mina ion o
in i o
i on bioa ailabili y because he cells exp ess in es inal mic o illi
enzymes and di e en ia ion ma ke s ha mimic human small in es ine en e ocy es [
27
,
49
].
Mo eo e , he lack o modula o s o sys emic ac o s o i on abso p ion could con ound
he ex apola ion o
in i o
i on abso p ion s udies [
50
]. Ne e heless, assessmen s o he
bioaccessibili y o i on and i s bioa ailabili y in Caco-2 cells a e use ul o p edic ing he
ela i e bioa ailabili y o a wide ange o plan oods. This in o ma ion can be used o selec
speci ic ood p oduc s o u he e alua ion in human die a y in e en ions o measu e
he bioa ailabili y o mine als om meals con aining mea subs i u es.
5. Conclusions
In summa y, excep o soy and mycop o ein bu ge s, he o al i on and zinc con en s
o he plan -based bu ge s we e signi ican ly lowe han hose om he bee . Likewise, zinc
bioa ailabili y was signi ican ly lowe om plan -based bu ge s, while i on bioa ailabili y
was compa able be ween he mea -con aining and he mea -subs i u ed bu ge s. Thus,
indi iduals consuming plan -based die s need o be awa e no only o he oods ha
a e ich in i on and zinc, bu also o he oods o ea in conjunc ion o maximise mine al