Chia Seed (Salvia hispanica L.) as a Source of Proteins and Bioactive Peptides with Health Benefits: A Review

The consumption of chia seed (Salvia hispanica L.) has increased in recent years due its high content of omega‐3 fatty acids and dietary fiber. This seed also has a high concentration of proteins and essential amino acids, becoming a promising source of bioactive peptides. The objective of this review was to identify the composition and the beneficial effects of chia seeds (S. hispanica L.), their proteins, peptides, and their potential impact on human health. The UniProt database was used to identify the chia proteins and their amino acid sequences. The BIOPEP database was used to analyze the peptides's bioactive potential. A total of 20 proteins were cataloged in chia seed, 12 of those were involved in the regular metabolic processes of the plant cells. However, eight proteins were specifically related to production and storage of plant lipids, thus explaining the high concentration of lipids in chia seeds (around 30%), especially omega‐3 fatty acids (around 20%). The analyses of amino acid sequences showed peptides with bioactive potential, including dipeptidyl peptidase‐IV inhibitors, angiotensin‐converting enzyme inhibitors, and antioxidant capacity. These results correlated with the main health benefits of whole chia seed in humans such as antioxidant capacity, and hypotensive, hypoglycemic, and anticholesterolemic effects. Such relation can be associated with chia protein and peptide compositions and therefore needs further investigation in vitro and in vivo.     

Chia Seed as a Source of Oil, Polysaccharide, and Protein

Chia seed, Salvia polystachya, was analyzed as a source of oil, polysaccharide, and protein for possible use by the food industry. Seeds were found to contain 30% oil of which more than 90% was composed of triglycerides. The fatty acid composition of the oil was found to consist mostly of C16:0, C18:0, C18:2 and C18:3. The protein content of chia seed was found to be 23.4%. A very viscous polysaccharide was isolated from the seeds. Acid hydrolysis followed by gas liquid chromatographic analysis demonstrated that xylose and arabinose were the major constituents of the polysaccharide. Seeds were found to contain niacin, riboflavin, and thiamin at a concentration of 83, 2 and 14 μg/g seed, respectively. Spectrochemical analysis showed the presence of eleven elements with calcium, potassium, and phosphorus being the most prominent. The percentage of unsaturated fatty acids, the concentration of protein and the viscosity of the polysaccharide in chia seeds would indicate that further research should be conducted to investigate possible food uses for these seeds.     

Chia seeds: Microstructure, mucilage extraction and hydration

Microstructural features of the chia seeds (Salvia hispanica L.) were studied by light and scanning electron microscopy. The study reports the effect of temperature (4-80 °C), pH (4-8) and seed:water ratio (1:20 and 1:40) on extraction of the mucilage of chia seeds and the effect of temperature (20-80 °C), pH (3-9) and ionic strength (0-1%) on hydration of the extracted mucilage. The mucilage was localized in cellular structures in the first three layers of the seed coat and upon full hydration filaments (mucilage fibers) became apparent and conformed to a transparent “capsule” attached to the seed. During extraction, temperature and seed:water ratio were found to have a significant effect on yield. Hydration of the extracted mucilage was significantly increased at high pH values, and was higher when salt concentration decreased, being maximal when the temperature reached values close to 80 °C.     

奇亚籽营养成分分析及其饮料工艺优化

为开发奇亚籽的营养价值,对黑、白两种奇亚籽的营养成分进行测定,并将其应用在饮料中。采用国标的方法测定基本营养成分,利用氨基酸自动分析仪、气相色谱-质谱联用仪(Gas Chromatography-Mass Spectrometer,GC-MS)分别测定氨基酸及脂肪酸含量,通过单因素实验和响应面试验优化奇亚籽柠檬汁饮料工艺配方。结果表明:黑、白奇亚籽粗蛋白质、粗脂肪、膳食纤维含量分别为16.40%、28.32%、34.67%和29.10%、30.48%、26.65%;二者水分和灰分含量均低于10%。共检出16种氨基酸,黑、白奇亚籽中必需氨基酸含量分别为7.37和7.77 g/100 g,占氨基酸总量的32.92%、38.39%。以氨基酸评分、化学评分为标准,第一限制性氨基酸均为蛋氨酸+半胱氨酸。黑、白奇亚籽中多不饱和脂肪酸分别占脂肪酸总量的82.82%和84.89%,其中omega-3占63.18%~68.37%,具有较高的食用价值。饮料最佳工艺配方:浓缩柠檬汁添加量10%、麦芽糖醇添加量14%、结冷胶添加量0.15%、奇亚籽添加量3%和甜蜜素添加量0.02%。在此条件下,饮料感官评分为(88.5±0.71)分,可制得口感好、色泽明亮、体系稳定均一的奇亚籽柠檬汁饮料。综合分析奇亚籽作为一种新食品原料,其营养价值丰富,并通过优化饮料制作工艺,为其在饮料深加工领域提供理论依据。     

Fatty acid profile of goat milk in diets supplemented with chia seed (Salvia hispanica L.)

Chia seed (Salvia hispanica L.) is the greatest known plant source of n-3 α-linolenic acid. The present study evaluated the effects of 3 inclusion levels of chia seed [zero (control); low, 2.7% (CLow); and high, 5.5% (CHigh)] in diets of dairy goats on milk yield and fatty acid profile. Nine Saanen dairy goats in the last third of lactation period, live weight 38 ± 8.7 kg, housed in metabolic cages, were fed iso-proteic and iso-energetic (160 g of crude protein/d and 11 MJ of metabolizable energy/d) diets. Gas chromatography was used to analyze fatty acid profile and total conjugated linoleic acid (CLA). Silver ion HPLC was used to analyze the isomeric profile of CLA. The results were subjected to variance analysis using a Latin square design repeated 3 × 3. The CHigh treatment was higher for dry matter, neutral detergent fiber, and acid detergent fiber intake compared with CLow and control diets. Digestibility was not affected by the inclusion of chia seeds. The CHigh diet improved N intake with respect to the control and CLow diet. Milk yield and chemical composition were not affected by the treatment. The milk fatty acid profile of C18:0, C18:1, C18:2, and C:20 was higher for CHigh than the other treatments. The in vitro gas production (mL of gas/g of dry matter) was lower in CHigh than the control diet. In conclusion, the addition of chia seeds at the CHigh level in dairy goat diets negatively affected in vitro rumen fermentation, but increased the milk fatty acid profile of C18:0, C18:1n-9 cis, and C:20, monounsaturated fatty acids, and polyunsaturated fatty acids. The total CLA content increased from 0.33 to 0.73% with the supplementation of chia to the diet, as well as the isomers cis-9,trans-11, trans-7,cis-9, trans-11,cis-13, and trans-12,trans-14.     

The influence of seed size on digestibility and growth performance of broiler chickens fed full-fat rapeseed

Two double low rapeseed varieties were separated into small and big seeds to study their nutritive value for broiler chickens. The seed weights for small and big seeds of spring rape variety Jaguar were 3.6 and 4.9 mg, and of winter rape Impala were 4.1 and 5.3 mg, respectively. Analytical results showed no significant differences in protein and fatty acid content between the big and small seeds. The small seeds contained more fibre constituents, eg lignin 13.7% higher for Jaguar and 3.4% higher for Impala, the other dietary fibre components show ed a similar trend. The big seeds, however, tended to be higher in fat and gross energy, but also in total glucosinolates. A 2 × 2 × 3 factorial design was performed on 24 broilers, to investigate the apparent digestibility and growth performance during three successive periods of balance trials, using diets consisting of 350 g kg^?1 full-fat rapeseeds and 650 g kg^?1 remainder feed mixture identical for all treatments. The diets with big seeds clearly showed higher digestibility for all measured dietary components. The surpluses as absolute percentage units respectively for dry matter were 2.8 (P < 0.001); gross energy 3.8 (P < 0.001); fat 7.9 (P < 0.001) and protein 1.6 (P = 0.045). The same trend was also found in the digestion of fatty acids and vitamin E. The big seeds displayed 7% higher (P = 0.071) growth rate and 8% higher (P = 0.002) feed conversion, respectively. Greater nutritional superiority of the big seeds was observed on the earlier growth ages, indicating the young birds are more sensitive to the seed size difference. It is concluded that the big seeds are more digestible than the small seeds and that a selection towards Digger seed size or a mechanical separation during processing will be beneficial.     

Antioxidant,free radical scavenging and type II diabetes‐related enzyme inhibition properties of traditionally processed Jequirity bean (Abrus precatorius L.)

The methanolic extract of raw Abrus precatorius (Jequirity bean, red‐ and black‐coloured seed coat) seeds contains a total phenolic content of 14.2 ± 0.39 g catechin equivalent/100 g extract. An analysis of phenolic profile revealed the presence of syringic acid, caffeic acid and (?)‐epicatechin in the methanolic extract of A. precatorius seeds. Encouraging levels of ferric reducing/antioxidant power (FRAP, 1247 mmol Fe[II]/mg extract), inhibition of β‐carotene bleaching (53.37%), 2,2‐Diphenyl‐1‐picryl‐hydrazyl (DPPH, 62.13%) and superoxide (64.47%) radical scavenging activities were exhibited by the extract of raw samples. Inhibition characteristics of 68.69%α‐amylase and 51.74%α‐glucosidase enzyme were also recorded under in vitro starch digestion bioassay. Sprouting + oil‐frying caused a significant increase in the total phenolic content and also substantially improved the antioxidant and free radical scavenging capacities, while soaking + cooking as well as open‐pan roasting treatments showed diminishing effects.     

In vitro multienzyme digestibility of protein of six varieties of African yam bean flours

The in vitro multienzyme protein digestibilities of the flours of six varieties of African yam bean (Sphenostylis stenocarpa), made from both whole seeds and dehulled seeds were investigated. The multienzyme system consisted of trypsin, chymotrypsin and peptidase. Digestibilities were determined for a 10 min digestion period. Both dehulling and heat treatment improved digestibility. Comparison of flours from raw whole seeds with those from dehulled seeds showed that digestibility was better in the latter, with an increase of 6.78%. Heat-treated whole seed flcurs gave a digestibility increase of 6.06% compared with raw flours whereas in the dehulled samples the digestibility increase of heat-treated flours over raw was 5.19%. Heat-treated dehulled seeds were better, with a digestibility increase of 5.90% over the heat-treated whole seed flours. No significant differences (P < 0.05) were observed in the digestibilities among the whole seed flours but significant differences were observed in the dehulled seed flours.     

Variation in oil quality and content of low molecular lipophilic compounds in chia seed oils

This study was conducted to characterize the lipid fraction of 15 chia seed samples originating from five countries (Argentina, Paraguay, Uganda, Bolivia, and Peru). On average, chia seeds contained 34.5 g oil per 100 g dry-solids, in which the average contents of sterols, tocopherols, squalene, carotenoids, and phenolic compounds were 7,061, 600, 17.7, 2.2, and 9.7 mg/kg of oil, respectively. Alpha-linolenic acid share varied from 54.35% to 60.48%, and was accompanied by declining shares of linoleic, palmitic, oleic, and stearic acid, respectively. Principal component analysis showed that chia oil induction time was positively correlated with tocopherols and phenols, while negatively with quality indices and squalene content.     

Chamaerops humilis L. var. argentea André Date Palm Seed Oil: A Potential Dietetic Plant Product

Chamaerops humilis L. var. argentea André (C. humilis) date palm seeds are an underutilized source of vegetable oil, and no studies describing their physicochemical characteristics to indicate the potential uses of this seed or seed oil have been reported. The oil content of the seeds is about 10%, mainly composed of oleic acid (38.71%), lauric acid (21.27%), linoleic acid (15.15%), palmitic acid (9.96%), and stearic acid (7.17%). The tocol (tocopherols and tocotrienols) content is 74 mg/100 g, with δ‐tocotrienol as the major contributor (31.91%), followed by α‐tocotrienol (29.37%), γ‐tocopherol (20.16%), and γ‐tocotrienol (11.86%). Furthermore, this oil shows high thermal stability. The differential scanning calorimetery curves revealed that the melting and crystallization points are 9.33 °C and –15.23 °C, respectively.     

In vitro evaluation of the antioxidant activities in the differentially processed seeds from underutilized legume, Bauhinia vahlii Wight & Arn

Antioxidant potential and total phenolics content of 70% acetone extracts of the raw and processed seeds of Bauhinia vahlii were evaluated. The extract of raw seeds contained higher levels of total phenolics (30.8 g/100 g) and tannins (19.6 g/100 g) compared to dry heated and soaking followed by autoclaving seed extracts. Extracts were screened for antioxidant and free radical scavenging activities using various chemical and in vitro model systems. In all the models, except DPPH radical scavenging activity, the extract from raw seeds manifested the strongest antioxidant activity than that from processed seeds. In β-carotene/linoleic acid emulsion system and superoxide scavenging activity, the raw seed extract registered more activity when compared to the standards (butylated hydroxyanisole and α-tocopherol). Whereas, the extract from dry heated seed exhibited higher DPPH^· scavenging activity (IC₅₀ 70.77 μg/mL) than the raw seeds (IC₅₀ 74.4 μg/mL). This study has to some extent validated the antioxidant potential of the seeds of B. vahlii.     

Water Adsorption Isotherms of Chia (Salvia hispanica L.) Seeds

The adsorption isotherms of chia seed (CS), black chia seed (BCS), white chia seed (WCS), and chia seed flour (CSF) were determined at different temperatures (20, 35, 50, and 65 °C) using gravimetric method. Several saturated salt solutions were selected to obtain different water activities in the range of 0.07 to 0.91. Adsorption isotherms were of type II, according to Brunauer’s classification. No significant differences were found between equilibrium data of WCS, BCS, and CS samples. CSF showed lower hygroscopic characteristics than seeds. The three-parameter Guggenheim–Anderson–de Boer (GAB) model was employed to fit the experimental data in the water activity range. The goodness of the fittings, using several statistical parameters, was satisfactory. The monolayer moisture content (kg (kg d.b.)⁻¹) calculated by the GAB model was 0.019 ± 0.004 for CS, BCS, and WCS and 0.015 ± 0.005 for CSF. The net isosteric sorption heat, calculated by means of the Clausius–Clapeyron equation, indicated that water is strongly bounded to chia at moisture content below 0.05 kg (kg d.b.)⁻¹.     

限制性酶解结合大孔树脂吸附对葵花籽蛋白色泽及功能特性的影响

以低温脱脂葵花籽粕为原料提取葵花籽蛋白,对其分别进行大孔树脂吸附脱色和限制性酶解结合大孔树脂吸附脱色处理,对比不同处理的葵花籽蛋白白度值、绿原酸含量及功能特性(溶解性、乳化性、乳化稳定性、起泡性、泡沫稳定性、持油性、持水性和凝胶性)的差异。结果表明:限制性酶解10 min结合大孔树脂吸附脱色的葵花籽蛋白白度值(L^*)为86.3,绿原酸含量为0.16 mg/g,溶解性为77.60%,起泡性为20.87%,乳化性为3.44 m²/g,乳化稳定性为118.51 min,均显著优于葵花籽蛋白和大孔树脂吸附脱色葵花籽蛋白(P <0.05),持水性为1.94 mL/g,显著优于葵花籽蛋白,但与大孔树脂吸附脱色葵花籽蛋白相当,持油性和泡沫稳定性分别为4.40 mL/g和69.62%,显著低于葵花籽蛋白和大孔树脂吸附脱色葵花籽蛋白,限制性酶解10 min结合大孔树脂吸附脱色葵花籽蛋白展现出较好的凝胶性。研究表明,经限制性酶解结合大孔树脂吸附脱色后,葵花籽蛋白色泽显著改善,其溶解性、乳化性、起泡性、持水性和凝胶性均显著提高。     

不同分子量红花籽抗氧化肽稳定性研究

目的:研究不同分子量红花籽蛋白抗氧化肽活性的稳定性。方法:以脱壳红花籽粕为实验材料,经复合酶酶解分离制备抗氧化肽,以1,1-二苯基-2-三硝基苯肼（1-diphenyl-2-trinitrophenylhydrazine,DPPH）自由基、超氧阴离子自由基（superoxide anion radical,O₂?·）及羟自由基（hydroxyl free radicals,·OH）清除能力为指标,探讨温度、pH、食品原辅料、金属离子及模拟胃肠消化等环境因素对不同分子量红花籽抗氧化肽活性的影响。结果:红花籽蛋白酶解物<3 kDa（SSPH-Ⅰ）、3~5 kDa（SSPH-Ⅱ）较分离前活性显著增加（P<0.05）,SSPH-Ⅲ（5~10 kDa）和SSPH-Ⅳ（>10 kDa）较分离前活性显著降低（P<0.05）,选取活性显著增加组分研究发现SSPH-Ⅰ抗氧化活性更加稳定,能在60~121 ℃高温、pH6~8弱酸弱碱条件下保持活性,各自由基清除率维持率达到90%以上,10 g/100 mL NaCl和葡萄糖、0.2 g/100 mL柠檬酸对SSPH-Ⅰ抗氧化活性有增强协同作用,各自由基清除率维持率增加至105%左右,10 g/100 mL的蔗糖和0.2 g/100 mL的防腐剂对活性影响不大,添加Cu2+、Zn2+和K+金属离子对SSPH-Ⅰ抗氧化稳定性显著下降（P<0.05）,其影响顺序为:Cu2+>Zn2+>K+>Mg2+>Ca2+,经模拟胃肠消化后活性较稳定,维持率为80%。结论:筛选得到<3 kDa红花籽蛋白抗氧化肽组分活性较高且稳定,为其工业化生产及应用提供理论依据。     

Evaluation of performance of dough and bread incorporating chia (Salvia hispanica L.)

As a result of the opinion given by the European Food Safety Authority about the safety of chia seed (Salvia hispanica L) and whole ground chia seed as food ingredients, they may be placed on the market in the European Community as novel food ingredients to be used in bread products. The objective of the present investigation was to develop new cereal-based products with increased nutritional quality by using chia and ground chia seeds (whole chia flour, semi-defatted chia flour and low-fat chia flour) in order to evaluate its potential as a bread-making ingredient. The samples with chia addition significantly increased the levels of proteins, lipids, ash and dietary fibre in the final product compared to the control sample. Breads with seeds or ground seeds showed similar technological quality to the control bread, except for the increase in specific bread volume, decrease in crumb firmness and change in crumb colour. Sensory analysis showed that the inclusion of chia increased overall acceptability by consumers. The thermal properties of the starch did not alter substantially with the inclusion of chia. However, the incorporation of chia inhibited the kinetics of amylopectin retrogradation during storage, which would be directly related to the delay in bread staling.     

Fatty Acid Composition of ‘Cerrado’ Seed Oils

The seeds of 28 species from ‘cerrado’, a typical savanna ecosystem of Brazil, were analysed for total lipid contents and fatty acid distribution. The seeds of 10 species presented contents above 150 g kg⁻¹, the highest yield reaching 335 g kg⁻¹. Distribution of fatty acids based on polyunsaturated compounds seems to be rare in seed oils from ‘cerrado’: only three seed oils were found to be based on linoleic acid and none on linolenic acid. Eight seed oils, four of them Fabales, presented palmitic acid as a dominant constituent. Half of the species presented oleic acid based seed oils. Two species stand out for unusual fatty acid distribution: Qualea grandiflora (Vochysiaceae) with 171 g kg⁻¹ of seed oil presenting 723 g kg⁻¹ of lauric acid and Serjania erecta (Sapindaceae) with 256 g kg⁻¹ of seed oil presenting 623 g kg⁻¹ of eicosenoic acid.     

Pasting and rheological properties of oat products dry-blended with ground chia seeds

Oat products containing β-glucan are documented for lowering blood cholesterol that could be beneficial for preventing coronary heart disease. Oat products (oat flour, oat bran concentrate, and Nutrim) were dry-blended with ground chia (Salvia hispanica L.) that contains omega-3 polyunsaturated fatty acids for improving nutritional and functional qualities. The pasting and rheological properties of oat–chia composites with 10, 20, and 50 g chia/100 g were characterized using Rapid Visco Analyzer followed by an advanced rheometer. Shear thinning properties were observed for all the composites. The pasting and rheological properties of oat products were not greatly influenced by 10 g or 20 g chia/100 g replacements but were improved at the 50 g/100 g replacement level. Also, these composites had improved water holding capacities compared with their starting oat products from 5 g to 250 g water/100 g, respectively. Also, whole chia seeds currently used in food products on the market are not easily utilized by the human body because of an extremely hard coat. These fine particle composites of oat products with ground chia were prepared by a feasible procedure for producing composites having improved nutritional value, texture quality, and functional food applications.     

In vitro gastrointestinal digestion of mango by-product snacks: Potential absorption of polyphenols and antioxidant capacity

Mango by-products are considered cheap sources of valuable foods and nutraceutical ingredients. In this work, antioxidant capacity (AOX), and potential absorption ability (PAA) of extractable polyphenols (EP) from mango by-product snacks (MB-S) were evaluated at different stages of in vitro gastrointestinal digestion. A wheat and oat-based control snack and three MB-S formulations (F1, F2 and F3) were prepared. Mango by-products were added at the expense of wheat in MB-S (paste-peel-seed): F1 (70-30-0), F2 (70-15-15), F3 (70-7.5-22.5). The highest release of polyphenols was observed after the gastric digestion. In the intestinal stage, MB-SF1 was the snack with the highest EP content (23.39 mg GAE/g db), two times greater than the control. Gallic acid and mangiferin were the main polyphenols identified in MB-S. The incorporation of mango seed in the MB-S reduced the polyphenols PAA by 10.29%. However, compared with the control snack, consumption of 30 g MB-SF1 provided additional 45 mg polyphenols.     

Chia (Salvia hispanica L.) oil extraction: Study of processing parameters

The processing parameters related with chia oil extraction employing screw press have not been studied yet. A Box–Behnken experimental design was used to study the optimization process by response surface analysis. The independent variables considered were seed moisture content, restriction die, screw press speed and barrel temperature, while the response variables measured were oil yield, fines content in oil and oil quality (acidity, peroxide index, K₂₃₂, K₂₇₀, values, antioxidant activity and total tocopherol content). Since chemical quality data of chia seeds oil pressed at different conditions was not affected, the response was optimize to maximize oil yield. The results suggested that 0.113 g/g dry solids (0.101 g/g seed), 6 mm restriction die, 20 rpm screw press speed and 30 °C barrel temperature were the best processing combination to maximize oil yield.     

元宝枫籽蛋白的营养性及理化性质

以元宝枫籽为原料,分别采用碱溶酸沉法和盐提法提取元宝枫籽分离蛋白（Acer truncatum Bunge. protein isolate,ABPI）和盐提蛋白（A. truncatum Bunge. salt extractable protein,ABSPI）,并对其营养性及理化性质进行对比研究。结果表明,ABPI和ABSPI中均含人体所需的8 种氨必需基酸,其中谷氨酸是主要的氨基酸,且ABPI和ABSPI必需氨基酸含量分别占总氨基酸含量的37.86%和38.45%。ABPI的表面疏水性（664.86）、总巯基（35.79 μmol/g）与二硫键（11.50 μmol/g）含量显著高于ABSPI（P＜0.05）,且热变性温度（128.05 ℃）也高于ABSPI（118.33 ℃）。而ABSPI持水性（4.64 mL/g）显著高于ABPI（2.46 mL/g）（P＜0.05）,持油性（3.58 mL/g）低于ABPI（4.82 mL/g）。ABPI和ABSPI的起泡性、起泡稳定性及乳化性随pH值的变化趋势均相似。傅里叶红外光谱显示ABPI与ABSPI均有典型的蛋白吸收峰,但ABSPI可能不具有三螺旋结构。扫描电子显微镜结果表明,2 种蛋白的微观结构明显不同,ABSPI呈有序簇状球形蛋白,而ABPI结构紧密,表面呈不规则山脊状。相比ABSPI,ABPI具有更好的理化性质和功能特性。