This site is a post-script to my teaching page at the
University of Guelph Growth & Structure
of Meat Animals and indexes my research since
retirement at the end of 2006. One experiment
leads to another for the curious scientist – why should retirement
terminate curiosity?
220. Swatland, H.J.
2007. Stratification of toughness in beef roasts. Meat Science, 77: 2-6.
Meat toughness can be measured
with cylindrical cores of meat cut in a shear press. But a whole roast of beef
is a far more complex system, with various layers affected to differing degrees
by cooking, as shown in this research using a fluorescence penetrometer.
It is widely known among meat
scientists that natural acidification causes meat to become progressively more
pale. This is essential to give a bright appearance to beef, but may become a
problem if it goes too far in pork and poultry meat. The experiments reported
in this paper explain how acidification changes the optical properties of meat.
The fact that you are reading
this proves that the internet has enhanced the way we communicate science.
Electronic publishing of science produced some major changes, a few of which
are documented here.
Plants store sugars as starch,
and starch granules are a major food ingredient. It is widely known among food
scientists that starch granules appear with a Maltese cross when viewed with a
polarizing microscope. Under certain conditions, the quadrants of the cross may
light up with diagonal pairs of colours. This
research explains why.
Sometimes waterfalls on the
Niagara Escarpment are surrounded by petrified mosses. This research shows how lime is deposited
on mosses.
In the age of the internet, we
all take popular science and the international communication of science for
granted – but how did these important ideas get started?
Our remote ancestors ate meat,
and so do most of us now. Meat has been around for the whole of our history
– in wars, religions, language, literature, laws and technology. Here are
some of the main points.
Have you ever seen flickering
patterns of light on the forest floor, or on the bottom of a swimming
pool? What would you see if you
were very small and you could swim under mosses in a waterfall?
Rainbow colours
of oil on water, and rainbow colours on beetles and butterfly
wings are a familiar sight, and the causes are well known . But what causes
rainbow colours on meat?
Water seeping through
limestone makes a major contribution to streams and rivers feeding into the
Great Lakes of North America. Scientists around the World are watching the
levels of carbon dioxide in the atmosphere, but levels are much higher in the
soil, where it is produced by microbial respiration. Carbon dioxide dissolves
in groundwater, but blows into the atmosphere when the groundwater emerges into
streams. What buffering will vast quantities of slowly moving groundwater give
us against rising carbon dioxide levels in the atmosphere? How might changes in
groundwater acidity and temperature affect our fish? Nobody knows right now,
which is why we need the baseline measurements in this research paper.
This shows that iridescence in
tuna muscle is just like iridescence in beef – most likely caused by
reflective interference from A-bands.
Preliminary research for
adapting on-line prediction methods to camel meat, including polarized-light
interferometry.
From textile fibers to
biological samples it looks as if light scattering in the sample has more
effect on colorimetry than the way in which the color is measured.
233.
Swatland, H.J. 2016. Interference colorimetry of starch granules. Color
Research and Application 41: 352-357. The subjective evaluation of
interference colours is a standard method of
identifying minerals in rock sections – but the reference charts are
highly variable because they use colorants in an attempt to simulate what
happens when sinusoidal waves interact with the spectral sensitivities of the
human eye. Being somewhat reluctant
to challenge a standard method in mineralogy, I chose to work on starch
granules and to solve an ancient problem in polarized light microscopy.
Jonathan Pereira, one of the great pioneers in pharmacology, reported in 1843
that starch granules exhibited a quadrant of diagonally paired interference
colors when viewed under a polarizing microscope fitted with a selenite
compensator. Research showed that the weighted-ordinate method of colorimetry
could be used to measure this phenomenon and that, as expected, it was a
function of the diameter of the starch granules. OK – this research will
get ignored by mineralogists, but it satisfies my curiosity.
234. Swatland, H.J. 2016.
Starch granules in polarized light, following Pereira into the ultraviolet. Quekett Journal of Microscopy 42: 601-609. This research challenges some current
beliefs held by food scientists and shows that the birefringence of starch
granules is caused primarily by
straight chains of amylose.
235. Swatland,
H.J. 2017. Colored clays in a groundwater stream, correlating fiber-optic
reflectance with electrical impedance. Hydrology Current Research 8:283.
Wikipedia suggests that the coloured clays on the
Niagara Escarpment might be caused by acid groundwater. No evidence of this was
found, whereas a combination of palaeontology and fibre-optic reflectance indicated that clay colour is determined by shale colour,
and that shale colour may be determined by aerobic
versus anaerobic conditions at the time of sediment formation.
236.
Swatland, H.J. 2017. A review of microcolorimetry for
textile, food, dental and optoelectronic industries. Asian Journal of
Engineering and Technology 5: 140-151 Macroscopic colorimetry is an
essential tool for color matching in many industries, but microcolorimetry
has been neglected. From individual fibers in complex textile pattern to the
dental fillings in our mouths – their colors can all be measured.
237.
Swatland, H.J. 2017. On wetting Muscovy glass and a peacock feather, following
Robert Hooke to investigate the colourimetry of meat
iridescence. Quekett Journal of Microscopy 43:
125-130. As the first great microscopist discovered, multilayer
interference survives under water while surface diffraction does not.
Hooke’s discovery is used to show that iridescence in meat is not from
surface diffraction, but from multilayer interference. The multilayers are the sarcomere discs
discovered by Bowman (another great microscopist).
238. Swatland, H.J.
2018. Iridescence in cooked venison – an optical phenomenon. Journal of
Nutritional Health and Food Engineering. 8(2): 105-108. This shows that
iridescence in venison is just like iridescence in beef and tuna – most
likely caused by reflective interference from A-bands because it is visible
under water..
239. Swatland, H.J. 2018. Colourimetry of chromatic aberration. Quekett
Journal of Microscopy. 43: 307-314.
The weighted-ordinate method of colourimetry
was used to detect chromatic aberration in a wide range of microscopes.
Extremes of microscope conditions had minimal effect on colourimetry
– thus showing there is no reason why colourimetry
cannot be used with light microscopes. In primitive microscopes, chromatic
aberration is made worse by interference effects. LED illuminators do not
interfere with colourimetry.
240. Swatland, H.J. 2019.
Fluorometry of natural latex from Maclura pomifera. Earth and Environmental Science Research and
Reviews. 2 (1). Maclura pomifera
is a small tree that produces rot-resistant wood and is found at the northern
edge of its range on the Niagara Escarpment. It has a fascinating geological history,
it seems to have worked its way north when South America became linked to North
America by plate tectonics and volcanic activity. Ancient animals such as the
giant ground sloth may originally have spread its seeds, but it was widely
planted in recent times to produce rot-resistant fence posts and, perhaps,
rot-resistant wood for water mills? It produces a strange fruit called an Osage
orange, which often dries to produce a bright green ball, something like a
pineapple in botanical structure. The fruit seems to resistant rotting because
of its high latex content. Latex is
often fluorescent so, of course, I had to measure it.
241.
Swatland, H.J. 2019. Colourimetry of iridescent
muscle fibres. Quekett
Journal of Microscopy. 43:357-362. The research gets one step closer to
finding how light is scattered when passing along the long axes of muscle fibres. A single dominant interference peak from A-band
reflectance gives a bright metallic colour, while fibres with multiple peaks have less chromatic intensity
and their colour coordinates converge on the central
white part of the CIE diagram.
242. Swatland,
H.J. 2019. Signal analysis of optical interference in relation to colorimetry
for measurements made along individual myofibers in cooked beef. Asian Journal
of Agriculture and Food Science 7: 107-113. The discovery made in the
previous paper (241) was that iridescence is a special case of light scattering
along myofibers – one or a small number of reflective A bands create a
metallic color, while numerous reflective A bands give rise to scattering with
very little color. But colors were still being judged subjectively. This research removed the subjective
element and signal analyses of interference peaks were correlated directly with
weighted-ordinate color coordinates of the same spectra.
The deep penetration of blue light through
great depths in the sea is well known to divers, but what happens in very
shallow freshwater streams? What
wavelengths for photosynthesis reach the aquatic mosses in shallow water?
244.
Swatland, H.J. 2020. Reflective layers in the fruit of Maclura
pomifera – bright enough to attract a Giant
Ground Sloth? Quekett Journal of Microscopy 43:
511-514. There is a popular but almost unprovable idea that Giant Ground
Sloths used to eat the fruits and distribute the seeds of the Osage orange. But
it is possible to explain the sometimes amazing bright green surface of the
fruit.
Most colorimeters have an
aperture of several square centimeters, but they are often used on samples with
a variegated appearance like the grain patterns on wood – light yellowish
lines separated by darker brown lines.
How are variegated samples integrated to give a simple set of
chromaticity coordinates? This research on exotic woods with a wide range of
grain pattern and color (each measured with different methods) showed a
connection between grain patterns and CIE x.
246. Swatland,
H.J. 2020. Microscopy of static and moving bubbles and leaf shadows. Quekett
Journal of Microscopy 43:713-716.
If terrestrial plant life evolved in shallow water, chlorophyll might
have evolved to use the red light not strongly attenuated by bubbles and
surface lensing of water.
An invited abbreviated version of #226 above, for a commercial
publication.
An invited conference presentation guessing how basic science, from
sensory perception, through x-ray diffraction for the effects of pH on interfilament separation, to interferometry in meat, might
be used to grade meat.
An invited conference
presentation on how on-line evaluation of meat might be applied for the grading
of camel meat.
An
invited conference presentation on how the terminology of US meat cuts may have
developed linguistically from Ancient Greece to the present day, via Norse and
Old English and French.
An
invited conference presentation on how light scattering affects meat
colorimetry.
A review
of how on-line evaluation of meat might be used in South America.
A book chapter expanding on how on-line evaluation might be used for
camel meat.
135.
Swatland, H.J. 2014. Growth of Meat Animals: Muscle. In: Carrick Devine &
Michael Dikeman, editors, Encyclopedia of Meat Sciences 2e, Vol. 2, Oxford:
Elsevier. Pp. 70-74.
Explains the histology of muscle growth in meat animals.
Cold groundwater in a river
bed creates suitable conditions for the spawning of brook trout (Salvelinus
fontinalis). In some locations along the Niagara Escarpment, groundwater
discharged from a primary aquifer may run, exposed to the atmosphere, down a
slope of clay into the river. At other locations, the flow above clay may be
within the overburden and only exposed at odd sites, such as the stream vent
described in this chapter. In
exposed streams, travertine deposited by the degassing of calcium-rich
groundwater after passing over clay is darker than upstream deposits. Spectrocolorimetry
of travertine, clays and shale, and electrical impedance of clays were used to
gather supporting information. Ecological sampling showed a rich river fauna in
the study area, mostly associated with pristine water.
A variety of optical methods
were used to investigate the flicker patterns of light in small waterfalls and
their splash zones. Flicker
patterns are important for the photosynthesis of plants in and around small
waterfalls, especially mosses. In a forest environment, the intensity of
incident light was increased when the sky was clouded and when deciduous trees
lacked leaves. Light penetrated
deeply into waterlogged splash zones by a series of reflections from living
moss leaves, as shown by using polarized light to detect Fresnel
reflectance. Penetration was also
high through dead, brown moss below the living moss, but this was because only
the walls of empty cells remained. Flicker patterns in flowing water originated
from surface lensing and bubbles, and were measured using optical fibers. In the splash zone, flickering was
increased by shadowing from moving moss leaves. Shadowing by bubbles was estimated from
transmittance measurements made with a microscope spectrophotometer. Shadowing
from large bubbles was mainly from the Becke line
(refractive index boundary) around the bubbles. Small bubbles cast strong shadows if the
Becke line occluded the central axis of the bubble.
138.
Swatland, H.J. 2018. Polarized light microscopy of moss leaves encrusted with
calcium carbonate. In Mosses.
Ecology, Life Cycle and Significance. Editors: O. Pokrovsky
et al. Chapter 12. P 275-287.A review of studies on calcium carbonate
deposition on mosses to produce travertine on the Niagara Escarpment. My
conclusion is there is nothing special about the moss – it grows fast and
can keep pace with petrification, eventually give rise to massive layers of
travertine.
139.
Swatland, H.J. 2018. Fascinating
iridescence. Canadian Meat Science Association website. A summary of
arguments to support multilayer interference from sarcomere discs.
140. Swatland, H.J. 2019.
Letter to the editor: Marsh and Bendall – pioneers in muscle biochemistry
and meat science. Meat Science 151:
60-62. This letter contains
lecture notes by James Bendall in 1982 explaining how he and Bruce Marsh
discovered calcium ions control muscle contraction and relaxation.
BOOKS
7.
Swatland, H.J. 2014. Eating Meat: Science and Consumption
Culture. 5M Publishing, Sheffield,
UK.
This is not a text-book but a
series of personal observations and arguments to support the idea that meat
consumption culture can give us a new perspective on meat science, and vice
versa.
TRANSLATIONS OF BOOKS
1.
H.J. Swatland. Estructura y desarrollo de
los animales de abasto.
Pedro Ducar Maluenda
(Translator). Vísceras y subproductos.
Los tejidos conjuntivos de
la canal. Estructura comercial
de la canal. Distribución anatómica
de los músculos de la canal. Estructura y propiedades de la
carne. Diferenciación de las fibras musculares y relaciones neuromusculares. Base celular del crecimiento muscular
postnatal. Crecimiento y desarrollo
animal. Conversión del músculo
en carne. Editorial Acribia.
ERRATA. The origin of the universe was
probably the consequence of a divine mistake, so the mistakes in my work should
be viewed in their proper light, as small echoes of the primaeval big bang.
228. The colour figure of iridescence is for iliocostalis not
iliopsoas, but identical iridescence can be seen in iliopsoas, so this error
does not worry me too much.
234. On page 602, corrections made to the final copy did not reach the printer – straight chains have 1-4 linkage, while branch points have 1-6 linkage.