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.
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.