Valorization of resistant starch from acorns as a new ingredient for chocolate milk puddings

Abstract

Aim: Despite being a fruit rich in resistant starch, acorns remain undervalued. Resistant starch is known to improve food acceptability when compared to traditional insoluble fibers, and recent research suggests the usage of acorn starch as an additive in fermented yogurt and milk products. Furthermore, non-thermal technologies such as high hydrostatic pressure and pulsed electric field can produce clean-labelled starches. Milk puddings are widely consumed all over the world and are usually produced using representative amounts of starch, making them an enticing food matrix for incorporating acorn starches. Hence, the effects of replacing commercial corn starch with acorn starch extracted by high hydrostatic pressure and pulsed electric field on the nutritional composition, functional and sensorial properties, and shelf-life of puddings were studied. Methods: Extraction of starch from Quercus robur acorns was performed using high hydrostatic pressure or pulsed electric field. Extracted starch was used in chocolate puddings, replacing commercial corn starch. Shelf-life storage and microbiological analysis were conducted over 28 days, along with texture, color, pH, and nutritional composition assessments. Rheological properties, scanning electron microscopy, in vitro digestion, and soluble sugar, fatty acid, and salt content analyses were performed. Sensorial analysis was conducted with 71 volunteer panelists to evaluate the acceptability, preference, and similarity of puddings. Results: Replacing the commercial corn starch with acorn starch improves the rheological properties of puddings and has no negative impact on the nutritional composition, internal structure, or in vitro digestibility. Sensory analysis revealed that panelists preferred the acorn starch puddings over the control. After 28 days of storage at 4°C, there was a greater stabilization of the color parameters and an improvement in textural parameters of puddings without compromising microbial safety. Conclusions: This study demonstrates the potential usage of starch from acorns in food applications, a fruit that is so undervalued.

Keywords

Acorn / valorization / resistant starch / ingredient / puddings / sensorial analysis

References

[1] Denk T, Grimm GW, Manos PS, Deng M, Hipp AL. An Updated Infrageneric Classification of the Oaks: Review of Previous Taxonomic Schemes and Synthesis of Evolutionary Patterns. In: Gil—Pelegrín E, Peguero—Pina JJ, Sancho—Knapik D, editors. Oaks Physiological Ecology. Exploring the Functional Diversity of Genus Quercus L. Cham: Springer; 2017. pp. 13-38.

[2] Silveira T. Bolota: 55% da produção é desperdiçada. Agro—Vida Vida Económica. 2017; 1715; 7.

[3] Castro LMG, Caço AI, Pereira CF, Sousa SC, Alexandre EMC, Saraiva JA, et al. Structure and properties of Quercus robur acorn starch extracted by pulsed electric field technology . Int J Biol Macromol. 2024; 260: 129328. [DOI] [PubMed]

[4] Castro LMG, Caço AI, Pereira CF, Sousa SC, Brassesco ME, Machado M, et al. Modification of Acorn Starch Structure and Properties by High Hydrostatic Pressure. Gels. 2023; 9: 757. [DOI] [PubMed] [PMC]

[5] Castro LMG, Ribeiro TB, Machado M, Alexandre EMC, Saraiva JA, Pintado M. Unraveling the Effect of Dehulling Methods on the Nutritional Composition of Acorn Quercus spp. J Food Compos Anal. 2022; 106: 104354. [DOI]

[6] Bojarczuk A, Skąpska S, Mousavi Khaneghah A, Marszałek K. Health benefits of resistant starch: A review of the literature. J Funct Foods. 2022; 93: 105094. [DOI]

[7] Sajilata MG, Singhal RS, Kulkarni PR. Resistant Starch—A Review. Compr Rev Food Sci Food Saf. 2006; 5: 1-17. [DOI] [PubMed]

[8] Castro LMG, Alexandre EMC, Saraiva JA, Pintado M. Impact of high pressure on starch properties: A review. Food Hydrocoll. 2020; 106: 105877. [DOI]

[9] Castro LMG, Alexandre EMC, Saraiva JA, Pintado M. Starch Extraction and Modification by Pulsed Electric Fields. Food Rev Int. 2023; 39: 2161-82. [DOI]

[10] Park S, Kim YR. Clean label starch: production, physicochemical characteristics, and industrial applications. Food Sci Biotechnol. 2020; 30: 1-17. [DOI] [PubMed] [PMC]

[11] Regulation (EC) No 1333/2008 of the European Parliament and of the Council of 16 December 2008 on food additives (Text with EEA relevance)[Internet]. [cited 2024 Feb 16]. Available from: https://eur—lex.europa.eu/eli/reg/2008/1333/oj/eng

[12] The most important carbohydrate[Internet]. Starch Europe; c2025 [cited 2024 Feb 16]. Available from: https://starch.eu/ingredients/

[13] Ares G, Baixauli R, Sanz T, Varela P, Salvador A. New functional fibre in milk puddings: Effect on sensory properties and consumers’ acceptability. LWT Food Sci Technol. 2009; 42: 710—6. [DOI]

[14] Gurmeric VE, Dogan M, Toker OS, Senyigit E, Ersoz NB. Application of Different Multi—criteria Decision Techniques to Determine Optimum Flavour of Prebiotic Pudding Based on Sensory Analyses. Food Bioprocess Technol. 2013; 6: 2844-59. [DOI]

[15] Richter VB, de Almeida TCA, Prudencio SH, de Toledo B. Proposing a ranking descriptive sensory method. Food Qual Prefer. 2010; 21: 611—20. [DOI]

[16] Kumar V, Chandra S, Kumar K, Goyal SK, Kumar L, Kumar A. Perishable and non—perishable food products roles in environment— A review. South Asian J Food Technol Environ. 2017; 3: 465-72.

[17] Commission Regulation (EC) No 2073/2005 of 15 November 2005 on microbiological criteria for foodstuffs (Text with EEA relevance)[Internet]. [cited 2024 Feb 16]. Available from: https://eur—lex.europa.eu/eli/reg/2005/2073/oj/eng

[18] ISO. Microbiology of the food chain — Horizontal method for the enumeration of microorganisms — Part 1: Colony count at 30 °C by the pour plate technique — Amendment 1: Clarification of scope. 2013.

[19] ISO. Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of presumptive Bacillus cereus — Colony—count technique at 30 degrees C — Amendment 1: Inclusion of optional tests. 2020.

[20] ISO. Microbiology of food and animal feeding stuffs — Horizontal method for the enumeration of yeasts and moulds — Part 2: Colony count technique in products with water activity less than or equal to 0.95. 2008.

[21] Biesta—Peters EG, Kinders SM, de Boer E. Validation by an interlaboratory collaborative trial of EN ISO 21528 — microbiology of the food chain — horizontal methods for the detection and enumeration of Enterobacteriaceae . Int J Food Microbiol. 2019; 288: 75-81. [DOI] [PubMed]

[22] Silva S, Costa EM, Borges A, Carvalho AP, Monteiro MJ, Pintado MME. Nutritional characterization of acorn flour (a traditional component of the Mediterranean gastronomical folklore). J Food Meas Charact. 2016; 10: 584—8. [DOI]

[23] ISO. Milk and milk products — Determination of nitrogen content — Part 1: Kjeldahl principle and crude protein calculation. 2014.

[24] ISO. Milk products and milk—based foods — Determination of fat content by the Weibull—Berntrop gravimetric method (Reference method) — Part 3: Special cases. 2005.

[25] Regulation (EU) No 1169/2011 of the European Parliament and of the Council of 25 October 2011 on the provision of food information to consumers, amending Regulations (EC) No 1924/2006 and (EC) No 1925/2006 of the European Parliament and of the Council, and repealing Commission Directive 87/250/EEC, Council Directive 90/496/EEC, Commission Directive 1999/10/EC, Directive 2000/13/EC of the European Parliament and of the Council, Commission Directives 2002/67/EC and 2008/5/EC and Commission Regulation (EC) No 608/2004 Text with EEA relevance[Internet]. [cited 2024 Feb 16]. Available from: https://eur—lex.europa.eu/eli/reg/2011/1169/oj/eng

[26] Brodkorb A, Egger L, Alminger M, Alvito P, Assunção R, Ballance S, et al. INFOGEST static in vitro simulation of gastrointestinal food digestion. Nat Protoc. 2019; 14: 991-1014. [DOI] [PubMed]

[27] Wichchukit S, O’Mahony M. The 9—point hedonic scale and hedonic ranking in food science: some reappraisals and alternatives. J Sci Food Agric. 2015; 95: 2167—78. [DOI] [PubMed]

[28] Arruda HS, Botrel DA, Fernandes RVB, Almeida MEF. Development and sensory evaluation of products containing the Brazilian Savannah fruits araticum (Annona crassiflora Mart.) and cagaita (Eugenia dysenterica Mart.) . Brazilian J Food Technol. 2016; 19: 4. [DOI]

[29] Anema S, Li Y. Further Studies on the Heat—induced, pH—dependent Dissociation of Casein from the Micelles in Reconstituted Skim Milk. LWT Food Sci Technol. 2000; 33: 335-43. [DOI]