{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,6,1]],"date-time":"2026-06-01T19:05:26Z","timestamp":1780340726125,"version":"3.54.1"},"reference-count":47,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T00:00:00Z","timestamp":1692230400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Nutricia Ltd."}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Nutrients"],"abstract":"<jats:p>(1) Background: Poor palatability, large volume, and lack of variety of some liquid and powdered protein substitutes (PSs) for patients with phenylketonuria (PKU) and tyrosinemia (TYR) can result in poor adherence. This study aimed to evaluate a new unflavoured, powdered GMP-based PS designed to be mixed into drinks, foods, or with other PSs, in patients with PKU and TYR. (2) Methods: Paediatric and adult community-based patients were recruited from eight metabolic centres and prescribed \u22651 sachet\/day (10 g protein equivalent (PE)) of the Mix-In-style PS over 28 days. Adherence, palatability, GI tolerance, and metabolic control were recorded at baseline and follow-up. Patients who completed at least 7 days of intervention were included in the final analysis. (3) Results: Eighteen patients (3\u201345 years, nine males) with PKU (n = 12) and TYR (n = 6) used the Mix-In-style PS for \u22657 days (mean 26.4 days (SD 4.6), range 11\u201328 days) alongside their previous PS, with a mean intake of 16.7 g (SD 7.7) PE\/day. Adherence was 86% (SD 25), and GI tolerance was stable, with n = 14 experiencing no\/no new symptoms and n = 3 showing improved symptoms compared to baseline. Overall palatability was rated satisfactory by 78% of patients, who successfully used the Mix-In-style PS in various foods and drinks, including smoothies, squash, and milk alternatives, as a top-up to meet their protein needs. There was no concern regarding safety\/metabolic control during the intervention. (4) Conclusions: The \u2018Mix-In\u2019-style PS was well adhered to, accepted, and tolerated. Collectively, these data show that providing a flexible, convenient, and novel format of PS can help with adherence and meet patients\u2019 protein needs.<\/jats:p>","DOI":"10.3390\/nu15163598","type":"journal-article","created":{"date-parts":[[2023,8,17]],"date-time":"2023-08-17T10:42:29Z","timestamp":1692268949000},"page":"3598","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":5,"title":["Evaluation of a New \u2018Mix-In\u2019 Style Glycomacropeptide-Based Protein Substitute for Food and Drinks in Patients with Phenylketonuria and Tyrosinemia"],"prefix":"10.3390","volume":"15","author":[{"given":"Marta","family":"Delsoglio","sequence":"first","affiliation":[{"name":"Research and Innovation, Nutricia Ltd., White Horse Business Park, Trowbridge BA14 0XQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rebecca","family":"Capener","sequence":"additional","affiliation":[{"name":"Research and Innovation, Nutricia Ltd., White Horse Business Park, Trowbridge BA14 0XQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anita","family":"MacDonald","sequence":"additional","affiliation":[{"name":"Dietetic Department, Birmingham Children\u2019s Hospital, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2579-8699","authenticated-orcid":false,"given":"Anne","family":"Daly","sequence":"additional","affiliation":[{"name":"Dietetic Department, Birmingham Children\u2019s Hospital, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Ashmore","sequence":"additional","affiliation":[{"name":"Dietetic Department, Birmingham Children\u2019s Hospital, Birmingham B4 6NH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sarah","family":"Donald","sequence":"additional","affiliation":[{"name":"Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lisa","family":"Gaff","sequence":"additional","affiliation":[{"name":"Cambridge University Hospitals NHS Foundation Trust, Cambridge CB2 0QQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Louise","family":"VanDorp","sequence":"additional","affiliation":[{"name":"Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Rachel","family":"Skeath","sequence":"additional","affiliation":[{"name":"Great Ormond Street Hospital for Children NHS Foundation Trust, London WC1N 3JH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Charlotte","family":"Ellerton","sequence":"additional","affiliation":[{"name":"University College London Hospitals NHS Foundation Trust, London WC1N 3BG, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Camille","family":"Newby","sequence":"additional","affiliation":[{"name":"Bristol University Hospitals NHS Foundation Trust, Bristol BS1 3NU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Georgina","family":"Dunning","sequence":"additional","affiliation":[{"name":"Bristol University Hospitals NHS Foundation Trust, Bristol BS1 3NU, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Clare","family":"Dale","sequence":"additional","affiliation":[{"name":"Queen Elizabeth Hospital, Birmingham B15 2TH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Inderdip","family":"Hunjan","sequence":"additional","affiliation":[{"name":"Bradford Teaching Hospitals, NHS Foundation Trust, Bradford BD5 0NA, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lucy","family":"White","sequence":"additional","affiliation":[{"name":"Sheffield Children\u2019s NHS Foundation Trust, Sheffield S10 2TH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Heather","family":"Allen","sequence":"additional","affiliation":[{"name":"Sheffield Children\u2019s NHS Foundation Trust, Sheffield S10 2TH, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Gary P.","family":"Hubbard","sequence":"additional","affiliation":[{"name":"Research and Innovation, Nutricia Ltd., White Horse Business Park, Trowbridge BA14 0XQ, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3811-3847","authenticated-orcid":false,"given":"Rebecca J.","family":"Stratton","sequence":"additional","affiliation":[{"name":"Research and Innovation, Nutricia Ltd., White Horse Business Park, Trowbridge BA14 0XQ, UK"},{"name":"Faculty of Medicine, University of Southampton, Southampton SO16 6YD, UK"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,8,17]]},"reference":[{"key":"ref_1","unstructured":"Chakrapani, A., Gissen, P., and McKiernan, P. 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