Starch Residues Research Articles

Structural characterizations of waxy maize starch residue following in vitro pancreatin and amyloglucosidase synergistic hydrolysis

The objective of this work was to determine if in vitro digestion altered the molecular structure and slow digestion property of waxy maize starch. The Englyst testing on partially hydrolysis residual starches showed an increase of RDS accompanied a reduction of RS with increasing time of digestion, while SDS was almost constant. Scanning electron micrographs showed that the pattern of enzymatic hydrolysis was inside-out layer-by-layer digestion. A threefold decrease in the average molecular weight of starch components was observed after α-amylolysis for 120 min. There were increases in the onset temperature, peak temperature and ratio of absorbance 1047/1022 cm −1, while the enthalpy of gelatinization, crystal structure, and crystallinity invaried. These changes suggest simultaneously enzymatic hydrolysis of both crystalline and amorphous regions of starch granule during in vitro digestion. SDS of starch residue also may consists of layered structure of amorphous and crystallite regions and located periphery of starch granules.

Mozambican Grass Seed Consumption During the Middle Stone Age

The role of starchy plants in early hominin diets and when the culinary processing of starches began have been difficult to track archaeologically. Seed collecting is conventionally perceived to have been an irrelevant activity among the Pleistocene foragers of southern Africa, on the grounds of both technological difficulty in the processing of grains and the belief that roots, fruits, and nuts, not cereals, were the basis for subsistence for the past 100,000 years and further back in time. A large assemblage of starch granules has been retrieved from the surfaces of Middle Stone Age stone tools from Mozambique, showing that early Homo sapiens relied on grass seeds starting at least 105,000 years ago, including those of sorghum grasses.

Impact of Empire Expansion on Household Diet: The Inka in Northern Chile's Atacama Desert

The impact of expanding civilization on the health of American indigenous societies has long been studied. Most studies have focused on infections and malnutrition that occurred when less complex societies were incorporated into more complex civilizations. The details of dietary change, however, have rarely been explored. Using the analysis of starch residues recovered from coprolites, here we evaluate the dietary adaptations of indigenous farmers in northern Chile's Atacama Desert during the time that the Inka Empire incorporated these communities into their economic system. This system has been described as “complementarity” because it involves interaction and trade in goods produced at different Andean elevations. We find that as local farming societies adapted to this new asymmetric system, a portion of their labor had to be given up to the Inka elite through a corvée tax system for maize production. In return, the Inka system of complementarity introduced previously rare foods from the Andean highlands into local economies. These changes caused a disruption of traditional communities as they instituted a state-level economic system on local farmers. Combined with previously published infection information for the same populations under Inka rule, the data suggest that there may have been a dual health impact from disruption of nutrition and introduction of crowd disease.

Characterization of maize amylose-extender ( ae) mutant starches: Part II. Structures and properties of starch residues remaining after enzymatic hydrolysis at boiling-water temperature

GEMS-0067 maize ae-line starches developed by the Germplasm Enhancement of Maize (GEM) project consist of 39.4–43.2% resistant starch (RS), which is larger than the existing ae-line starches of H99 ae, OH43 ae, B89 ae, and B84 ae (11.5–19.1%) as reported in part I of the study. The objective of this study was to understand the mechanism of the RS formation in the GEMS-0067 ae-line starch. In the current study, we analyzed the structures and properties of the RS residues that remained after enzymatic hydrolysis of the ae-line starches at 95–100 °C. The RS residues consisted of two major components: large starch molecules of average degrees of polymerization (DP) 840–951 with a few branches and small starch molecules (average DP 59–74) with mostly linear chains. All the RS residues had a semi-crystalline structure with the B-type polymorph and displayed high onset (100.7–107.7 °C), peak (118.6–121.4 °C), and conclusion (139.7–158.8 °C) gelatinization temperatures. After the maize ae-mutant starches were defatted with methanol, the RS contents decreased to 27.8–28.9% for the GEMS-0067 ae-line starches and 9.0–11.0% for the existing ae-line starches. The RS residues were attributed to the presence of long-chain double-helical crystallites derived from amylose and the intermediate component (IC). These crystallites present in native ae-line starches had gelatinization temperatures above 100 °C and maintained the semi-crystalline structures after enzymatic hydrolysis at 95–100 °C.

Sourdough bread: Starch digestibility and postprandial glycemic response

To evaluate the influence of sourdough fermentation on starch digestibility in bread, four experimental breads were obtained, prepared from two different wheat flours (whole or white) by two different leavening techniques (sourdough and with Saccharomyces cerevisiae). Products were analyzed for their starch, fiber and resistant starch (RS) content and then submitted to in vitro hydrolysis with porcine alpha-amylase. On the same breads, postprandial blood glucose was evaluated in healthy human subjects. Both sourdough fermented breads gave glycaemic responses significantly lower ( p < 0.001) than the corresponding products leavened with S. cerevisiae. On the contrary, the presence of fiber did not influence the glycaemic potential of breads. RS levels were higher in the sourdough products, whereas no differences were observed either in the rate of starch hydrolysis or in the degree of polymerization of the starch residues after the in vitro hydrolysis. We may conclude that sourdough fermentation is a technique able to reduce the glycaemic response to bread and that the mechanism does not seem related to the rate of starch hydrolysis.

Late Pleistocene to Early Holocene Plant Movements in Southern Kyushu, Japan

From the late Pleistocene to early Holocene in Japan, subtropical and temperate forest elements moved northwards. This affected human choices and access to food sources. More settled patterns of living spread northwards gradually, and northern hunting-gathering-fishing people began cultivating vegetables and cereal crops. This poster reports the presence of ancient starch residues on stone artefacts in Kagoshima Prefecture, southern Kyushu. The oldest residues recovered are dated by context to about 30,000 14C yr BP. If such residues can be identified, it may be possible to detect a hypothesized early phase of tropical plant movement northwards during warmer climate peaks in the late terminal Pleistocene, as well as during the long period of Holocene warming that followed. As an initial step towards identification, the morphological characteristics and condition of the starch granules are described and compared to those of other sites in early Japan.

Directly dated starch residues document early formative maize ( Zea mays L.) in tropical Ecuador

The study of maize (Zea mays L.) domestication has advanced from questions of its origins to the study-and debate-of its dietary role and the timing of its dispersal from Mexico. Because the investigation of maize's spread is hampered by poor preservation of macrobotanical remains in the Neotropics, research has focused on microbotanical remains whose contexts are often dated by association, leading some to question the dates assigned. Furthermore, some scholars have argued that maize was not introduced to southwestern Ecuador until approximately 4150-3850 calendar years before the present (cal B.P.), that it was used first and foremost as a fermented beverage in ceremonial contexts, and that it was not important in everyday subsistence, challenging previous studies based on maize starch and phytoliths. To further investigate these questions, we analyzed every-day cooking vessels, food-processing implements, and sediments for starch and phytoliths from an archaeological site in southwestern Ecuador constituting a small Early Formative village. Employing a new technique to recover starch granules from charred cooking-pot residues we show that maize was present, cultivated, and consumed here in domestic contexts by at least 5300-4950 cal B.P. Directly dating the residues by accelerator mass spectrometry (AMS) radiocarbon measurement, our results represent the earliest direct dates for maize in Early Formative Ecuadorian sites and provide further support that, once domesticated approximately 9000 calendar years ago, maize spread rapidly from southwestern Mexico to northwestern South America.

Effect of Nylon Bag and Protozoa on In Vitro Corn Starch Disappearance

An in vitro experiment was carried out to study whether the presence of protozoa in nylon bags can explain the underestimation of the in situ degradation of slowly degradable starch. Corn of a high (flint) and a low (dent) vitreousness variety was ground over a 3-mm screen, weighed in nylon bags with a pore size of 37μ m, and washed in cold water. Samples of washed cornstarch were incubated in 40-mL tubes with faunated and defaunated ruminal fluid. An additional amount of washed corn, in nylon bags, was inserted in each incubation tube. Incubations were carried out for 0, 2, 4, 6, 12, and 24h, and starch residue in tube and nylon bag was determined. In general, starch disappearance from the nylon bag was less than from the tube, and was less with faunated than defaunated rumen fluid, but corn variety did not affect starch disappearance. When no protozoa were present, the disappearance of starch from the bags was higher after 6 and 12h incubation compared with presence of protozoa. However, in the tubes, there was no difference in starch disappearance due to presence or absence of protozoa. Estimated lag time was higher in presence (4.6h) then absence (3.6h) of protozoa. It was concluded that the effect of presence or absence of protozoa on starch disappearance differs within or outside nylon bags. The reduced disappearance rate of starch inside the nylon bags in the presence of protozoa helps to explain the underestimation of starch degradation based on the in sacco procedure when compared with in vivo data upon incubation of slowly degradable starch sources.

4,300-Year-old chimpanzee sites and the origins of percussive stone technology

Archaeological research in the African rainforest reveals unexpected results in the search for the origins of hominoid technology. The ancient Panin sites from Côte d'Ivoire constitute the only evidence of prehistoric ape behavior known to date anywhere in the world. Recent archaeological work has yielded behaviorally modified stones, dated by chronometric means to 4,300 years of age, lodging starch residue suggestive of prehistoric dietary practices by ancient chimpanzees. The "Chimpanzee Stone Age" pre-dates the advent of settled farming villages in this part of the African rainforest and suggests that percussive material culture could have been inherited from an common human-chimpanzee clade, rather than invented by hominins, or have arisen by imitation, or resulted from independent technological convergence.

Desenvolvimento de substratos alternativos para o cultivo de cogumelos comestíveis e medicinal

With the objective of evaluating the potential of residues from cassava industry, in the elaboration of substrate for the cultivation of the Pleurotus sajor-caju, Lentinula edodes and Agaricus blazei, were made assays using cassava residues, eucalyptus and pinus sawdust, in solid (potatodextrose- agar-PDA) and liquid media (PD). For this, the dextrose (2%) was replaced by cassava bark, starch residue and cassava fiber, pinus and eucalyptus sawdust, and with the following combination: I (50% eucalyptus sawdust (ES) + 25% cassava bark (CB) + 25% starch residue (ER)), II (25% ES + 50% CB + 25% ER) and III (25% ES + 25% CB + 50% ER). PDA and PD were used as control to solid and liquid media treatments, respectively. To evaluate the basidiocarps production, L. edodes and P. sajor-caju were cultived in the composition I, II and III into polypropylene bags (15 x 24 cm). The results showed that, in the solid medium, the bark and fiber of cassava increased the mycelial growth, while the bark and starch were the best treatments in liquid medium. Using the mixtures of residues, the composition II in solid medium, and the composition I in liquid medium, were the treatments that most increased the mycelial growth. For L. edodes, no substratum provided the production of mushrooms, occurring only the formation of young basidiocarps that was more intense in substratum I. For P. sajor-caju, in the substratum I it had the biggest production of basidiocarps followed of substratum II. These results indicate the potential of cassava residues for the cultivation of the Pleurotus sajor-caju, Lentinula edodes and Agaricus blazei.

Evidence for introduced taro ( Colocasia esculenta) and lesser yam ( Dioscorea esculenta) in Lapita-era (c. 3050–2500 cal. yr BP) deposits from Bourewa, southwest Viti Levu Island, Fiji

Starch residue, pollen and phytolith analysis was carried out on coralline deposits from a c. 3050–2500 cal. yr BP Lapita site at Bourewa, Viti Levu, Fiji. Starch grains, calcium oxalate crystals and xylem cells of introduced Colocasia esculenta and Dioscorea esculenta were identified, involving a process of elimination of possible taxa by cross-correlation of microfossil types. The data provide an eastward extension of direct evidence of Lapita horticulture in Remote Oceania previously identified in Vanuatu.

Root and Tuber Phytoliths and Starch Grains Document Manioc(Manihot Esculenta), Arrowroot(Maranta Arundinacea), andLlerén (Calatheasp.)at the Real Alto Site, Ecuador

Although roots and tubers are dietary staples in many parts of the world, their use is difficult to document archaeologically because their organic remains are often poorly preserved in archaeological sediments. Here we describe the first diagnostic phytoliths from the underground storage organs of the important New World agricultural crops manioc or yuca (Manihot esculenta Crantz), arrowroot (Maranta arundinacea L.), and lleren (Calathea allouia [Aubl.] Lindl.) and demonstrate their usefulness for identifying prehistoric root and tuber processing with a study of stone artifacts from a Valdivia 3 (2800–2400 B.C., calibrated) household at Real Alto, Ecuador. Gelatinized starch (heat-altered) and unaltered starch from maize (Zea mays L.), arrowroot, and manioc were also found on these stone tools. Our data document early evidence for manioc in Ecuador's coastal lowlands. In combination, these phytoliths and starch residues provide evidence that both raw and cooked foods were processed in this early mixed agricultural economy.

Shear-induced aggregate formation in starch solutions

Shear-thickening behavior and shear-induced pattern formation have been observed in semidilute starch solutions. While the shear-thickening behavior is due to breaking up of highly concentrated gel-like structures dispersed in dilute starch solutions, the pattern-forming behavior is not well understood. The pattern formation, observed when the starch solution is exposed to a high shear field, is a consequence of shear-induced aggregation and is not related to shear-thickening behavior. The patterns have been observed above a certain critical threshold shear rate regardless of the starch type. In this report, it is shown that the product of shear time and fourth power of shear rate is a controlling factor for the formation of shear-induced aggregates in starch solutions. Since starch solutions prepared under harsh conditions did not show shear-induced aggregate formation, it is suggested that the aggregates are formed from incompletely solubilized starch residues in its apparent solution.

Analysis of Plant Microfossils in Archaeological Deposits from Two Remote Archipelagos: The Marshall Islands, Eastern Micronesia, and the Pitcairn Group, Southeast Polynesia

ABSTRACT Pollen and starch residue analyses were conducted on 24 sediment samples from archaeological sites on Maloelap and Ebon Atolls in the Marshall Islands, eastern Micronesia, and Henderson and Pitcairn Islands in the Pitcairn Group, Southeast Polynesia. The sampled islands, two of which are “mystery islands” (Henderson and Pitcairn), previously occupied and abandoned before European contact, comprise three types of Pacific islands: low coral atolls, raised atolls, and volcanic islands. Pollen, starch grains, calcium oxylate crystals, and xylem cells of introduced non-Colocasia Araceae (aroids) were identified in the Marshalls and Henderson (ca. 1,900 yr B.P. and 1,200 yr B.P. at the earliest, respectively). The data provide direct evidence of prehistoric horticulture in those islands and initial fossil pollen sequences from Pitcairn Island. Combined with previous studies, the data also indicate a horticultural system on Henderson comprising both field and tree crops, with seven different cultigens, ...

Microfossils of introduced starch cultigens from an early wetland ditch in New Zealand

Pollen, phytolith and starch residue analyses of a wetland ditch at Motutangi, far northern New Zealand reveals evidence of early environment and introduced cultigens. During the period of use or infilling, local vegetation largely comprised Gleichenia-Restionaceae swamp and disturbed forest. Starch residues of Colocasia esculenta (taro), Dioscorea sp. (yam) and Ipomoea sp. (possibly I. batatas, sweet potato) are identified, here, and suggest that the ditch systems of far northern New Zealand may have been used for extensive cultivation of taro and other crops. The results include the first direct evidence of Dioscorea in ancient Polynesia.

Plant microfossil analysis of soils from Polynesian stonefields in South Auckland, New Zealand

Pollen, biogenic silica and starch residue analyses of soils from archaeological stonework complexes in South Auckland, northern New Zealand, reveal evidence of palaeo-environments and vegetation, including agricultural crops. A broad sampling strategy involving minimal disturbance to features was used (35 composite soil samples from six sites) to determine the extent to which the complexes were used for agriculture, identifying specific crops and pinpointing areas for subsequent intensive excavation. Starch and other residues of Ipomoea batatas (sweet potato) and Colocasia esculenta (taro), introduced by prehistoric Polynesians, were identified in a range of stonefield features at four sites. Zea mays (maize), an early European introduction, was identified at two sites. The study also highlights problems of downward displacement and preservation of plant microfossils in dryland soils. The data represent initial extensive, multi-microfossil analysis of archaeological stonework complexes.

Microfossil analysis of Lapita deposits in Vanuatu reveals introduced Araceae (aroids)

Starch residue, pollen and phytolith analysis was carried out on 14 coralline soil and potsherd samples from a c. 2700 BP Lapita site on Uripiv Island, Vanuatu. Starch grains, calcium oxylate crystals and xylem cells of introduced Araceae (aroids) were identified, providing the most compelling evidence to date of Lapita horticulture in Remote Oceania. Phytoliths indicate that local vegetation was dominated by Arecaceae (palms). Pollen was present in extremely low concentrations.

A combined procedure for recovering phytoliths and starch residues from soils, sedimentary deposits and similar materials

Presented is a combined procedure for recovering phytoliths and starch residues from soils, sedimentary deposits and similar materials. It is designed to be reliable, simple and time efficient, and is outlined in detail and summary as a practical, step-by-step method. It has been carried out successfully on many types of soils and other deposits, including clays, silts and sands; waterlogged, porous, peaty, volcanic and coralline soils; and sediment cores and coprolites from a range of environmental settings in both tropical and temperate climates. Mounting phytoliths and starch residues on slides for microscopy is included.

Characteristics of native and enzymatically hydrolyzed ragi ( Eleusine coracana) and rice ( Oryza sativa) starches

The compositional, structural and enzymatic digestibility profiles of starches isolated from ragi and rice were determined. Although, the gelatinization temperature (73±2 °C) and GPC elution profiles of both starches on Sepharose CL-2B gel were comparable, the peak (PV: 273 RVU) and set back (SB: 196 RVU) viscosities and also the thermic energy (TE: 34.78 cal/g) values for ragi starch were considerably higher than for rice starch (PV: 200 RVU; SB: 150 RVU and TE: 26.54 cal/g). Upon digestion with α-amylase (AA) ( human salivary), β-amylase (BA) ( barley malt), pullulanase (PN) ( Klebsiella pneumoniae) and amyloglucosidase (AG) ( Aspergillus niger), the hydrolysates from AA contained glucose, maltose and oligosaccharides of 15–20 DP prominently, whereas, those from BA, PN and AG contained only maltose, maltotriose and glucose, respectively. The molecular weight ( M W) and degree of crystallinity of the starch residues from the enzymatic digests of ragi starch were significantly higher than of rice starch. The SEM examination of the residues indicated high degree of fragmentation in the case of rice but only a few bigger chunks in case of ragi. These parameters may help to explain subtle differences in the digestibility and physiological properties that exist between ragi and rice starches.

Microbial production of hydrogen from starch-manufacturing wastes

Effective hydrogen production from starch-manufacturing wastes by microorganisms was investigated. Continuous hydrogen production in high yield of 2.7 mol H 2 mol −1 glucose was attained by a mixed culture of Clostridium butyricum and Enterobacter aerogenes HO-39 in the starch waste medium consisting of sweet potato starch residue as a carbon source and corn steep liquor as a nitrogen source in a repeated batch culture. Rhodobacter sp. M-19 could produce hydrogen from the supernatant of the culture broth obtained in the repeated batch culture of C. butyricum and E. aerogenes HO-39. Hydrogen yield of 4.5 mol H 2 mol −1 glucose was obtained by culturing Rhodobacter sp. M-19 in the supernatant supplemented with 20 μg l −1 Na 2MoO 4·2H 2O and 10 mg l −1 EDTA in a repeated batch culture with pH control at 7.5. Therefore, continuous hydrogen production with total hydrogen yield of 7.2 mol H 2 mol −1 glucose from the starch remaining in the starch residue was attained by the repeated batch culture with C. butyricum and E. aerogenes HO-39 and by the successive repeated batch culture with Rhodobacter sp. M-19.