Paleoproteomic profiling of organic residues on prehistoric pottery from Malta.

Mass spectrometry-based approaches have been successfully applied for identifying ancient proteins in bones and other tissues. On the contrary, there are relatively few examples of the successful recovery and identification of archeological protein residues from ceramic artifacts; this is because ceramics contain much lower levels of proteins which are extensively degraded by diagenetic effects. In this paper, we report the results of the characterization of proteins extracted from pottery of the Maltese site of Bahrija, the guide-site for the Bahrija period (half of 9th-second half of eighth century BCE), recently identified as the final part of the Borg in-Nadur culture. Proteomic data here reported confirm that one of the major issue of these kind of studies is represented by contamination of animal and human agents that may complicate endogenous protein identification and authentication. The samples tested included a small group of ceramic forms, namely three tableware and six coarse ware thought to have been used in food preparation and/or storage. In this context, the limited availability of paleobotanical and archeozoological analyses may be compensated by the outcomes of the first proteomics profiling which, even if obtained on a limited selection of vessels, revealed the centrality of wheat in the diet of the ancient community of Bahrija. The data have been deposited to the ProteomeXchange with identifier < PXD022848 > .

Molecular and isotopic evidence for milk, meat, and plants in prehistoric eastern African herder food systems.

The development of pastoralism transformed human diets and societies in grasslands worldwide. The long-term success of cattle herding in Africa has been sustained by dynamic food systems, consumption of a broad range of primary and secondary livestock products, and the evolution of lactase persistence (LP), which allows digestion of lactose into adulthood and enables the milk-based, high-protein, low-calorie diets characteristic of contemporary pastoralists. Despite the presence of multiple alleles associated with LP in ancient and present-day eastern African populations, the contexts for selection for LP and the long-term development of pastoralist foodways in this region remain unclear. Pastoral Neolithic (c 5000 to 1200 BP) faunas indicate that herders relied on cattle, sheep, and goats and some hunting, but direct information on milk consumption, plant use, and broader culinary patterns is rare. Combined chemical and isotopic analysis of ceramic sherds (n = 125) from Pastoral Neolithic archaeological contexts in Kenya and Tanzania, using compound-specific δ13C and Δ13C values of the major fatty acids, provides chemical evidence for milk, meat, and plant processing by ancient herding societies in eastern Africa. These data provide the earliest direct evidence for milk product consumption and reveal a history of reliance on animal products and other nutrients, likely extracted through soups or stews, and plant foods. They document a 5,000-y temporal framework for eastern Africa pastoralist cuisines and cultural contexts for selection for alleles distinctive of LP in eastern Africa.

Interpretation of bulk nitrogen and carbon isotopes in archaeological foodcrusts on potsherds.

RATIONALE: Foodcrust, the charred deposit adhering to the surface of containers, is a possible source of information on the function of ancient vessels and the subsistence of prehistoric humans. While the carbon isotope ratios in those materials are useful in detecting the usage of C4 plants, the reliability of nitrogen isotopic signatures has not been fully investigated. METHODS: The validity of bulk nitrogen isotope ratios has previously been investigated in coastal or riverine environments, where multiple resources from terrestrial and aquatic ecosystems were available, but not in terrestrial settings which provide a simpler mixing of terrestrial animals and plants. Hence, we conducted an exhaustive study on charred deposits on potsherds at two inland archaeological sites belonging to prehistoric Jomon hunter-gathers in central Japan, focusing on δ15 N values and atomic N/C ratios determined using an isotope ratio mass spectrometer and an elemental analyzer, respectively. RESULTS: For both sites, the δ15 N values showed significant correlations with the N/C ratios among samples from the inner surface, suggesting that these have recorded animal contribution. Furthermore, previous studies of Neolithic pottery from North Europe and Far East Russia bearing strong marine signatures had shown reasonably higher δ15 N values and N/C ratios in comparison with our data from terrestrial settings. On the other hand, some charred materials probably originating from plant starch showed lower values with both parameters. Samples from the outer surface produced less meaningful isotopic and elemental ratios altered by a thermal effect and/or contamination from soot. CONCLUSIONS: When the samples of foodcrusts were selected carefully from the inner surface, bulk nitrogen isotopes and N/C ratios reflect the composition of what was cooked or processed in containers. This will provide useful information for understanding the human adaptation from the Late Pleistocene to the Holocene in conjunction with residual lipid analyses.

A 100-Year Review: Sensory analysis of milk.

Evaluation of the sensory characteristics of food products has been, and will continue to be, the ultimate method for evaluating product quality. Sensory quality is a parameter that can be evaluated only by humans and consists of a series of tests or tools that can be applied objectively or subjectively within the constructs of carefully selected testing procedures and parameters. Depending on the chosen test, evaluators are able to probe areas of interest that are intrinsic product attributes (e.g., flavor profiles and off-flavors) as well as extrinsic measures (e.g., market penetration and consumer perception). This review outlines the literature pertaining to relevant testing procedures and studies of the history of sensory analysis of fluid milk. In addition, evaluation methods outside of traditional sensory techniques and future outlooks on the subject of sensory analysis of fluid milk are explored and presented.

The History of Infant Formula: Quality, Safety, and Standard Methods.

Food-related laws and regulations have existed since ancient times. Egyptian scrolls prescribed the labeling needed for certain foods. In ancient Athens, beer and wines were inspected for purity and soundness, and the Romans had a well-organized state food control system to protect consumers from fraud or bad produce. In Europe during the Middle Ages, individual countries passed laws concerning the quality and safety of eggs, sausages, cheese, beer, wine, and bread; some of these laws still exist today. But more modern dietary guidelines and food regulations have their origins in the latter half of the 19th century when the first general food laws were adopted and basic food control systems were implemented to monitor compliance. Around this time, science and food chemistry began to provide the tools to determine "purity" of food based primarily on chemical composition and to determine whether it had been adulterated in any way. Since the key chemical components of mammalian milk were first understood, infant formulas have steadily advanced in complexity as manufacturers attempt to close the compositional gap with human breast milk. To verify these compositional innovations and ensure product quality and safety, infant formula has become one of the most regulated foods in the world. The present paper examines the historical development of nutritional alternatives to breastfeeding, focusing on efforts undertaken to ensure the quality and safety from antiquity to present day. The impact of commercial infant formulas on global regulations is addressed, along with the resulting need for harmonized, fit-for-purpose, voluntary consensus standard methods.

Analysis as border patrol: chemists along the boundary between pure food and real adulteration.

A disputed butter competition in Pennsylvania in 1895 brought the cultural, environmental, and scientific character of the Era of Adulteration to the fore. The incident put a spotlight on the confusing character of adulteration and the increasingly prominent role of chemical analysts in arbitrating that confusion. This article uses the case to explore the role scientific analysts played on the border between pure food products and adulterated ones, arguing that the scientists fighting adulteration gained credibility within a cultural environment where trust and confidence were problematic and an agricultural environment where spatial connections between producers and consumers were difficult to see. They were not just detectors of chemical impurities, but participants in a vital cultural arbitration. Characterizing them for their cultural role helps demonstrate that their practices and identity were (and remain) relevant for more than just detection and eradication, then and in the future.

Wine chemistry and flavor: looking into the crystal glass.

Over the past century, advances in analytical chemistry have played a significant role in understanding wine chemistry and flavor. Whereas the focus in the 19th and early 20th centuries was on determining major components (ethanol, organic acids, sugars) and detecting fraud, more recently the emphasis has been on quantifying trace compounds including those that may be related to varietal flavors. In addition, over the past 15 years, applications of combined analytical and sensory techniques (e.g., gas chromatography-olfactometry) have improved the ability to relate chemical composition to sensory properties, whether identifying impact compounds or elucidating matrix effects. Many challenges remain, however. This paper discusses some of the recent research aimed at understanding how viticultural and enological practices influence grape and wine volatiles. In addition, the challenges in linking composition to sensory properties will also be reviewed. Finally, future advances in linking grape, yeast, and human genomics to wine chemistry and flavor will be briefly discussed.

Food chemistry and U.S. food regulations.

The Agriculture and Food Chemistry Division (AGFD) was founded in 1908 shortly after passage of the first U.S. food regulations in 1906. Modern food regulations started with the passage of the Food Drug and Cosmetic Act in 1938. This Act has been amended several times to keep pace with developments in food chemistry. In 1958 the Food Additives Amendment was enacted to control substances added to food. Since 1958 scientific techniques have been developed to evaluate the safety and carcinogenicity of substances in the food supply. In the 1970s and 1980s AGFD symposia and books addressed compounds of concern in foods. In the 1990s food safety and nutrition regulations followed new developments in food and nutrition chemistry. Recently, the well-studied toxin acrylamide was discovered in food and presented regulators with new questions on safety and control in the food supply. Discoveries and developments in chemistry such as those in nanotechnology will continue to present challenges to food regulators.

Chemical food safety issues in the United States: past, present, and future.

Considerable advances have been made over the past century in the understanding of the chemical hazards in food and ways for assessing and managing these risks. At the turn of the 20th century, many Americans were exposed to foods adulterated with toxic compounds. In the 1920s the increasing use of insecticides led to concerns of chronic ingestion of heavy metals such as lead and arsenic from residues remaining on crops. By the 1930s, a variety of agrochemicals were commonly used, and food additives were becoming common in processed foods. During the 1940s and 1950s advances were made in toxicology, and more systematic approaches were adopted for evaluating the safety of chemical contaminants in food. Modern gas chromatography and liquid chromatography, both invented in the 1950s and 1960s, were responsible for progress in detecting, quantifying, and assessing the risk of food contaminants and adulterants. In recent decades, chemical food safety issues that have been the center of media attention include the presence of natural toxins, processing-produced toxins (e.g., acrylamide, heterocyclic aromatic amines, and furan), food allergens, heavy metals (e.g., lead, arsenic, mercury, cadmium), industrial chemicals (e.g., benzene, perchlorate), contaminants from packaging materials, and unconventional contaminants (melamine) in food and feed. Due to the global nature of the food supply and advances in analytical capabilities, chemical contaminants will continue to be an area of concern for regulatory agencies, the food industry, and consumers in the future.

One hundred years of progress in food analysis.

Food and agricultural products comprise complex and diverse chemical mixtures that historically have presented challenges for assessing food safety, nutrient content, stability, and sensory qualities. The analysis of food composition has significantly evolved over the past 100 years, progressing from reliance on predominantly "wet chemistry" laboratory methods from the early to mid-20th century to their gradual replacement by modern instrumental techniques. Pioneering developments in pH instruments, spectrophotometry, chromatography/separations, and spectrometry often had immediate applications to food analysis. Continuous improvements in methodology over this period have led to significant enhancements in analytical accuracy, precision, detection limits, and sample throughput, thereby expanding the practical range of food applications. The growth and infrastructure of the modern global food distribution system heavily relies on food analysis-beyond simple characterization-as a tool for new product development, quality control, regulatory enforcement, and problem-solving.

Legacy of Wilbur O. Atwater: human nutrition research expansion at the USDA--interagency development of food composition research.

The systematic chemical analysis of foods for human consumption in the United States had its origin with Wilbur O. Atwater. This activity began in the 1860s while Atwater was a student at Yale University and continued through his tenures at Wesleyan University and the Storrs (Connecticut) Experiment Station. These activities moved with Atwater to the USDA in Washington, DC and ultimately to the Henry D. Wallace Beltsville Agricultural Research Center in Beltsville, MD early in the 1900s. During the first half of the 20th century, food composition activities were guided by the discovery of new essential nutrients and the need to measure and tabulate their levels in foods. Later in the century, the association between diet and chronic diseases was recognized. As a result, collaborations were established between other food- and health-related government agencies, the food industry, and many universities. At the same time, computer and communication technology greatly advanced, which became integral to laboratory instrumentation and allowed data in the National Nutrient Databank System to be available electronically. Simultaneously, accuracy of analytical data came under scrutiny and a new paradigm was established in collaboration with governmental metrology units worldwide. Advances in computer technology and the increased focus on accuracy of analytical data subsequently led to the development of quality indicators for all food composition data. Recently, increased consumption of dietary supplements resulted in the broadening of food composition efforts and development of new collaborations with government agencies, several industries, and universities.

Available lysine in foods: a brief historical overview.

A brief historical overview is presented on the development of the science addressing lysine bioavailability in foods. Early observations that dietary protein utilization did not always correlate with gross amino acid composition led to an understanding that the amino acid lysine, in particular, can be easily damaged during food processing. Conventional amino acid analysis, involving a strong acid hydrolysis step, can lead to a significant degree of overestimation of lysine in processed foods. More recently, it has been found that not only food lysine content values but also estimates of lysine digestibility and digestible lysine contents may be erroneous. Estimates of absorbed (true ileal digestible) reactive lysine are accurate measures of available lysine. Technically, bioassays such as the slope-ratio assay determine utilized rather than available lysine.

We're living on corn!

A review of Michael Pollan's The omnivore's dilemma: a natural history of four meals and Bill McKibben's Deep economy: the wealth of communities and the durable future.